[Federal Register Volume 85, Number 219 (Thursday, November 12, 2020)]
[Rules and Regulations]
[Pages 72312-72469]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-23757]



[[Page 72311]]

Vol. 85

Thursday,

No. 219

November 12, 2020

Part V





Department of Commerce





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National Oceanic and Atmospheric Administration





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50 CFR Part 218





Taking and Importing Marine Mammals; Taking Marine Mammals Incidental 
to the U.S. Navy Training and Testing Activities in the Northwest 
Training and Testing (NWTT) Study Area; Final Rule

  Federal Register / Vol. 85 , No. 219 / Thursday, November 12, 2020 / 
Rules and Regulations  

[[Page 72312]]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 218

[Docket No. 201020-0272]
RIN 0648-BJ30


Taking and Importing Marine Mammals; Taking Marine Mammals 
Incidental to the U.S. Navy Training and Testing Activities in the 
Northwest Training and Testing (NWTT) Study Area

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Final rule; notification of issuance of Letters of 
Authorization.

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SUMMARY: NMFS, upon request from the U.S. Navy (Navy), issues these 
regulations pursuant to the Marine Mammal Protection Act (MMPA) to 
govern the taking of marine mammals incidental to the training and 
testing activities conducted in the Northwest Training and Testing 
(NWTT) Study Area. The Navy's activities qualify as military readiness 
activities pursuant to the MMPA, as amended by the National Defense 
Authorization Act for Fiscal Year 2004 (2004 NDAA). These regulations, 
which allow for the issuance of Letters of Authorization (LOA) for the 
incidental take of marine mammals during the described activities and 
timeframes, prescribe the permissible methods of taking and other means 
of effecting the least practicable adverse impact on marine mammal 
species and their habitat, and establish requirements pertaining to the 
monitoring and reporting of such taking.

DATES: Effective from November 9, 2020 to November 8, 2027.

ADDRESSES: A copy of the Navy's application, NMFS' proposed and final 
rules and subsequent LOAs for the existing regulations, and other 
supporting documents and documents cited herein may be obtained online 
at: www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities. In case 
of problems accessing these documents, please use the contact listed 
here (see FOR FURTHER INFORMATION CONTACT).

FOR FURTHER INFORMATION CONTACT: Leah Davis, Office of Protected 
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Purpose of Regulatory Action

    These regulations, issued under the authority of the MMPA (16 
U.S.C. 1361 et seq.), provide the framework for authorizing the take of 
marine mammals incidental to the Navy's training and testing activities 
(which qualify as military readiness activities) from the use of sonar 
and other transducers, in-water detonations, and potential vessel 
strikes based on Navy movement in the NWTT Study Area. The NWTT Study 
Area includes air and water space off the coast of Washington, Oregon, 
and Northern California; in the Western Behm Canal, Alaska; and 
portions of waters of the Strait of Juan de Fuca and Puget Sound, 
including Navy pierside and harbor locations in Puget Sound (see Figure 
1-1 of the Navy's rulemaking/LOA application).
    NMFS received an application from the Navy requesting seven-year 
regulations and authorizations to incidentally take individuals of 
multiple species of marine mammals (``Navy's rulemaking/LOA 
application'' or ``Navy's application''). Take is anticipated to occur 
by Level A harassment and Level B harassment as well as a very small 
number of serious injuries or mortalities incidental to the Navy's 
training and testing activities.
    Section 101(a)(5)(A) of the MMPA (16 U.S.C. 1371(a)(5)(A)) directs 
the Secretary of Commerce (as delegated to NMFS) to allow, upon 
request, the incidental, but not intentional taking of small numbers of 
marine mammals by U.S. citizens who engage in a specified activity 
(other than commercial fishing) within a specified geographical region 
if, after notice and public comment, the agency makes certain findings 
and issues regulations that set forth permissible methods of taking 
pursuant to that activity, as well as monitoring and reporting 
requirements. Section 101(a)(5)(A) of the MMPA and the implementing 
regulations at 50 CFR part 216, subpart I, provide the legal basis for 
issuing this final rule and the subsequent LOAs. As directed by this 
legal authority, this final rule contains mitigation, monitoring, and 
reporting requirements.

Summary of Major Provisions Within the Final Rule

    The following is a summary of the major provisions of this final 
rule regarding the Navy's activities. Major provisions include, but are 
not limited to:
     The use of defined powerdown and shutdown zones (based on 
activity);
     Measures to reduce the likelihood of ship strikes;
     Activity limitations in certain areas and times that are 
biologically important (e.g., for foraging or migration) for marine 
mammals;
     Implementation of a Notification and Reporting Plan (for 
dead or live stranded marine mammals); and
     Implementation of a robust monitoring plan to improve our 
understanding of the environmental effects resulting from the Navy 
training and testing activities.
    Additionally, the rule includes an adaptive management component 
that allows for timely modification of mitigation or monitoring 
measures based on new information, when appropriate.

Background

    The MMPA prohibits the ``take'' of marine mammals, with certain 
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA direct the 
Secretary of Commerce (as delegated to NMFS) to allow, upon request, 
the incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of proposed authorization is 
provided to the public for review and the opportunity to submit 
comments.
    An authorization for incidental takings shall be granted if NMFS 
finds that the taking will have a negligible impact on the species or 
stocks and will not have an unmitigable adverse impact on the 
availability of the species or stocks for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking and other means of effecting the least practicable adverse 
impact on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of the species or stocks for 
taking for certain subsistence uses (referred to in this rule as 
``mitigation measures''); and requirements pertaining to the monitoring 
and reporting of such takings. The MMPA defines ``take'' to mean to 
harass, hunt, capture, or kill, or attempt to harass, hunt, capture, or 
kill any marine mammal. The Analysis and Negligible Impact 
Determination section below discusses the definition of ``negligible 
impact.''
    The NDAA for Fiscal Year 2004 (2004 NDAA) (Pub. L. 108-136) amended 
section 101(a)(5) of the MMPA to remove the ``small numbers'' and

[[Page 72313]]

``specified geographical region'' provisions indicated above and 
amended the definition of ``harassment'' as applied to a ``military 
readiness activity.'' The definition of harassment for military 
readiness activities (Section 3(18)(B) of the MMPA) is (i) Any act that 
injures or has the significant potential to injure a marine mammal or 
marine mammal stock in the wild (Level A Harassment); or (ii) Any act 
that disturbs or is likely to disturb a marine mammal or marine mammal 
stock in the wild by causing disruption of natural behavioral patterns, 
including, but not limited to, migration, surfacing, nursing, breeding, 
feeding, or sheltering, to a point where such behavioral patterns are 
abandoned or significantly altered (Level B harassment). In addition, 
the 2004 NDAA amended the MMPA as it relates to military readiness 
activities such that the least practicable adverse impact analysis 
shall include consideration of personnel safety, practicality of 
implementation, and impact on the effectiveness of the military 
readiness activity.
    More recently, Section 316 of the NDAA for Fiscal Year 2019 (2019 
NDAA) (Pub. L. 115-232), signed on August 13, 2018, amended the MMPA to 
allow incidental take rules for military readiness activities under 
section 101(a)(5)(A) to be issued for up to seven years. Prior to this 
amendment, all incidental take rules under section 101(a)(5)(A) were 
limited to five years.

Summary and Background of Request

    On March 11, 2019, NMFS received an application from the Navy for 
authorization to take marine mammals by Level A harassment and Level B 
harassment incidental to training and testing activities (which qualify 
as military readiness activities) from the use of sonar and other 
transducers and in-water detonations in the NWTT Study Area over a 
seven-year period beginning when the 2015--2020 authorization expires. 
In addition, the Navy requested incidental take authorization by 
serious injury or mortality for up to three takes of large whales from 
vessel strikes over the seven-year period. We received revised 
applications on June 6, 2019 and June 21, 2019, which provided 
revisions in the take number estimates and vessel strike analysis, and 
the Navy's rulemaking/LOA application was found to be adequate and 
complete. On August 6, 2019 (84 FR 38225), we published a notice of 
receipt (NOR) of application in the Federal Register, requesting 
comments and information related to the Navy's request for 30 days. On 
October 4, 2019, the Navy submitted an amendment to its application 
which incorporated new Southern Resident killer whale offshore density 
information, and on December 19, 2019, the Navy submitted an amendment 
to its application which incorporated revised testing activity numbers. 
On June 2, 2020, we published a notice of proposed rulemaking (85 FR 
33914) and requested comments and information related to the Navy's 
request for 45 days. All comments received during the NOR and the 
proposed rulemaking comment periods were considered in this final rule. 
Comments received on the proposed rule are addressed in this final rule 
in the Comments and Responses section.
    The following types of training and testing, which are classified 
as military readiness activities pursuant to the MMPA, as amended by 
the 2004 NDAA, will be covered under the regulations and LOAs: Anti-
submarine warfare (sonar and other transducers, underwater 
detonations), mine warfare (sonar and other transducers, underwater 
detonations), surface warfare (underwater detonations), and other 
testing and training (sonar and other transducers). The activities will 
not include pile driving/removal or use of air guns.
    This would be the third time NMFS has promulgated incidental take 
regulations pursuant to the MMPA relating to similar military readiness 
activities in the NWTT Study Area. Specifically, five-year regulations 
addressing training in the Northwest Training Range Complex were first 
issued on November 9, 2010 (75 FR 69295; November 10, 2010) and five-
year regulations addressing testing in the NUWC Keyport Range Complex 
were issued on April 11, 2011 (76 FR 20257; April 12, 2011). 
Regulations addressing both the training and testing activities from 
the two previous separate rules, Northwest Training and Testing (NWTT), 
were issued and were effective from November 9, 2015 through November 
8, 2020 (80 FR 73555; November 24, 2015). For this third round of 
rulemaking, the activities the Navy is planning to conduct are largely 
a continuation of ongoing activities conducted over the past 10 years 
under the previous rulemakings, with the addition of some new training 
and testing activities, as well as additional mitigation measures.
    The Navy's mission is to organize, train, equip, and maintain 
combat-ready naval forces capable of winning wars, deterring 
aggression, and maintaining freedom of the seas. This mission is 
mandated by Federal law (10 U.S.C. 8062), which requires the readiness 
of the naval forces of the United States. The Navy executes this 
responsibility in part by training and testing at sea, often in 
designated operating areas (OPAREA) and testing and training ranges. 
The Navy must be able to access and utilize these areas and associated 
sea space and air space in order to develop and maintain skills for 
conducting naval operations. The Navy's testing activities ensure naval 
forces are equipped with well-maintained systems that take advantage of 
the latest technological advances. The Navy's research and acquisition 
community conducts military readiness activities that involve testing. 
The Navy tests ships, aircraft, weapons, combat systems, sensors, and 
related equipment, and conducts scientific research activities to 
achieve and maintain military readiness.
    The Navy has been conducting training and testing activities in the 
NWTT Study Area for decades, with some activities dating back to at 
least the early 1900s. The tempo and types of training and testing 
activities fluctuate because of the introduction of new technologies, 
the evolving nature of international events, advances in warfighting 
doctrine and procedures, and changes in force structure (e.g., 
organization of ships, submarines, aircraft, weapons, and personnel). 
Such developments influence the frequency, duration, intensity, and 
location of required training and testing activities, however the 
Navy's planned activities for the period of this rule will be largely a 
continuation of ongoing activities. In addition to ongoing activities, 
the Navy is planning some new training activities such as torpedo 
exercise--submarine training and unmanned underwater vehicle 
training.\1\ The Navy is also planning some new testing activities, 
including: At-sea sonar testing, Mine Countermeasure and Neutralization 
testing, mine detection and classification testing, kinetic energy 
weapon testing, propulsion testing, undersea warfare testing, vessel 
signature evaluation, acoustic and oceanographic research, radar and 
other system testing, and simulant testing.\2\
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    \1\ Some of the activities included here are new to the 2020 
NWTT FSEIS/OEIS, but are not new to the Study Area. TORPEX--SUB 
activity was previously analyzed in 2010 as part of the Sinking 
Exercise. The Sinking Exercise is no longer conducted in the NWTT 
Study Area and the TORPEX--SUB activity is now a separate activity 
included in the 2020 NWTT FSEIS/OEIS. Unmanned underwater vehicle 
activity was analyzed in 2010 as a testing activity, but is now 
being included as a training activity.
    \2\ Mine detection and classification testing was analyzed in 
2010 in the Inland waters, but was not previously analyzed in the 
Offshore waters. Vessel signature evaluation testing was analyzed in 
2010 as a component to other activities, but is included in the list 
of new activities because it was not previously identified as an 
independent activity.

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[[Page 72314]]

    The Navy's rulemaking/LOA application reflects the most up-to-date 
compilation of training and testing activities deemed necessary to 
accomplish military readiness requirements. The types and numbers of 
activities included in the rule account for fluctuations in training 
and testing in order to meet evolving or emergent military readiness 
requirements. These regulations cover training and testing activities 
that will occur for a seven-year period following the expiration of the 
current MMPA authorization for the NWTT Study Area, which expires on 
November 8, 2020.

Description of the Specified Activity

    A detailed description of the specified activity was provided in 
our Federal Register notice of proposed rulemaking (85 FR 33914; June 
2, 2020); please see that notice of proposed rulemaking or the Navy's 
application for more information. Since publication of the proposed 
rule, the Navy has made some minor changes to its planned activities, 
all of which are in the form of reductions and thereby have the effect 
of reducing the impact of the activity. See the discussion of these 
changes below. In addition, since publication of the proposed rule, 
additional mitigation measures have been added, which are discussed in 
detail in the Mitigation Measures section of this rule. The Navy has 
determined that acoustic and explosive stressors are most likely to 
result in impacts on marine mammals that could rise to the level of 
harassment, and NMFS concurs with this determination. Additional detail 
regarding these activities is provided in Chapter 2 of the 2020 NWTT 
Final Supplemental Environmental Impact Statement (FSEIS)/Overseas EIS 
(OEIS) (2020 NWTT FSEIS/OEIS) (https://www.nwtteis.com) and in the 
Navy's rulemaking/LOA application (https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities) and are summarized here.

Dates and Duration

    The specified activities can occur at any time during the seven-
year period of validity of the regulations, with the exception of the 
activity types and time periods for which limitations have explicitly 
been identified (see Mitigation Measures section). The planned number 
of training and testing activities are described in the Detailed 
Description of the Specified Activities section (Tables 3 through 4).

Geographical Region

    The NWTT Study Area is composed of established maritime operating 
and warning areas in the eastern North Pacific Ocean region, including 
areas of the Strait of Juan de Fuca, Puget Sound, and Western Behm 
Canal in southeastern Alaska. The Study Area includes air and water 
space within and outside Washington state waters, within Alaska state 
waters, and outside state waters of Oregon and Northern California (see 
Figure 1 in the proposed rule). The eastern boundary of the Offshore 
Area portion of the Study Area is 12 nautical miles (nmi) off the 
coastline for most of the Study Area, including southern Washington, 
Oregon, and Northern California. The Offshore Area includes the ocean 
all the way to the coastline only along that part of the Washington 
coast that lies beneath the airspace of W-237 and the Olympic Military 
Operations Area. The Study Area includes four existing range complexes 
and facilities: The Northwest Training Range Complex, the Keyport Range 
Complex, Carr Inlet Operations Area, and the Southeast Alaska Acoustic 
Measurement Facility (Western Behm Canal, Alaska). In addition to these 
range complexes, the Study Area also includes Navy pierside locations 
where sonar maintenance and testing occurs as part of overhaul, 
modernization, maintenance, and repair activities at Naval Base Kitsap, 
Bremerton; Naval Base Kitsap, Bangor; and Naval Station Everett. 
Additional detail can be found in Chapter 2 of the Navy's rulemaking/
LOA application.

Overview of Training and Primary Mission Areas

    The Navy categorizes its at-sea activities into functional warfare 
areas called primary mission areas. These activities generally fall 
into the following eight primary mission areas: Air warfare; amphibious 
warfare; anti-submarine warfare (ASW); electronic warfare; 
expeditionary warfare; mine warfare (MIW); strike warfare; and surface 
warfare (SUW). The Navy's planned activities for NWTT generally fall 
into the following six primary mission areas: Air warfare; anti-
submarine warfare; electronic warfare; expeditionary warfare; mine 
warfare; and surface warfare. Most activities addressed in the NWTT 
Study Area are categorized under one of these primary mission areas. 
Activities that do not fall within one of these areas are listed as 
``other activities.'' Each warfare community (surface, subsurface, 
aviation, and expeditionary warfare) may train in some or all of these 
primary mission areas. The testing community also categorizes most, but 
not all, of its testing activities under these primary mission areas. A 
description of the sonar, munitions, targets, systems, and other 
material used during training and testing activities within these 
primary mission areas is provided in Appendix A (Navy Activities 
Descriptions) of the 2020 NWTT FSEIS/OEIS.
    The Navy describes and analyzes the effects of its activities 
within the 2020 NWTT FSEIS/OEIS. In its assessment, the Navy concluded 
that sonar and other transducers and in-water detonations were the 
stressors most likely to result in impacts on marine mammals that could 
rise to the level of harassment as defined under the MMPA. Therefore, 
the Navy's rulemaking/LOA application provides the Navy's assessment of 
potential effects from these stressors in terms of the various warfare 
mission areas in which they would be conducted. Those mission areas 
include the following:
     Anti-submarine warfare (sonar and other transducers, 
underwater detonations);
     expeditionary warfare;
     mine warfare (sonar and other transducers, underwater 
detonations);
     surface warfare (underwater detonations); and
     other (sonar and other transducers).
    The Navy's training and testing activities in air warfare and 
electronic warfare do not involve sonar and other transducers, 
underwater detonations, or any other stressors that could result in 
harassment, serious injury, or mortality of marine mammals. Therefore, 
the activities in air warfare and electronic warfare are not discussed 
further in this rule, but are analyzed fully in the 2020 NWTT FSEIS/
OEIS. Additional detail regarding the primary mission areas was 
provided in our Federal Register notice of proposed rulemaking (85 FR 
33914; June 2, 2020); please see that notice of proposed rulemaking or 
the Navy's application for more information.

Overview of Testing Activities Within the NWTT Study Area

    The Navy's research and acquisition community engages in a broad 
spectrum of testing activities in support of the Fleet. These 
activities include, but are not limited to, basic and applied 
scientific research and technology development; testing, evaluation, 
and maintenance of systems (missiles, radar, and sonar) and platforms 
(surface ships, submarines, and aircraft); and acquisition of systems 
and platforms.

[[Page 72315]]

The individual commands within the research and acquisition community 
include Naval Air Systems Command, Naval Sea Systems Command, and 
Office of Naval Research.

Description of Stressors

    The Navy uses a variety of sensors, platforms, weapons, and other 
devices, including ones used to ensure the safety of Sailors and 
Marines, to meet its mission. Training and testing with these systems 
may introduce acoustic (sound) energy or shock waves from explosives 
into the environment. The following subsections describe the acoustic 
and explosive stressors for marine mammals and their habitat (including 
prey species) within the NWTT Study Area. Because of the complexity of 
analyzing sound propagation in the ocean environment, the Navy relied 
on acoustic models in its environmental analyses and rulemaking/LOA 
application that considered sound source characteristics and varying 
ocean conditions across the NWTT Study Area. Stressor/resource 
interactions that were determined to have de minimis or no impacts 
(e.g., vessel noise, aircraft noise, weapons noise, and explosions in 
air) were not carried forward for analysis in the Navy's rulemaking/LOA 
application. No Major Training Exercises (MTEs) or Sinking Exercise 
(SINKEX) events are planned in the NWTT Study Area. NMFS reviewed the 
Navy's analysis and conclusions on de minimis sources and finds them 
complete and supportable.
    Acoustic stressors include acoustic signals emitted into the water 
for a specific purpose, such as sonar, other transducers (devices that 
convert energy from one form to another--in this case, into sound 
waves), as well as incidental sources of broadband sound produced as a 
byproduct of vessel movement, aircraft transits, and use of weapons or 
other deployed objects. Explosives also produce broadband sound but are 
characterized separately from other acoustic sources due to their 
unique hazardous characteristics. Characteristics of each of these 
sound sources are described in the following sections.
    In order to better organize and facilitate the analysis of 
approximately 300 sources of underwater sound used for training and 
testing by the Navy, including sonar and other transducers and 
explosives, a series of source classifications, or source bins, were 
developed. The source classification bins do not include the broadband 
sounds produced incidental to vessel and aircraft transits and weapons 
firing. Noise produced from vessel, aircraft, and weapons firing 
activities are not carried forward because those activities were found 
to have de minimis or no impacts, as stated above.
    The use of source classification bins provides the following 
benefits:
     Provides the ability for new sensors or munitions to be 
covered under existing authorizations, as long as those sources fall 
within the parameters of a ``bin;''
     Improves efficiency of source utilization data collection 
and reporting requirements anticipated under the MMPA authorizations;
     Ensures a conservative approach to all impact estimates, 
as all sources within a given class are modeled as the most impactful 
source (highest source level, longest duty cycle, or largest net 
explosive weight) within that bin;
     Allows analyses to be conducted in a more efficient 
manner, without any compromise of analytical results; and
     Provides a framework to support the reallocation of source 
usage (hours/explosives) between different source bins, as long as the 
total numbers of takes remain within the overall analyzed and 
authorized limits. This flexibility is required to support evolving 
Navy training and testing requirements, which are linked to real world 
events.
Sonar and Other Transducers
    Active sonar and other transducers emit non-impulsive sound waves 
into the water to detect objects, navigate safely, and communicate. 
Passive sonars differ from active sound sources in that they do not 
emit acoustic signals; rather, they only receive acoustic information 
about the environment, or listen. In this rule, the terms sonar and 
other transducers will be used to indicate active sound sources unless 
otherwise specified.
    The Navy employs a variety of sonars and other transducers to 
obtain and transmit information about the undersea environment. Some 
examples are mid-frequency hull-mounted sonars used to find and track 
enemy submarines; high-frequency small object detection sonars used to 
detect mines; high-frequency underwater modems used to transfer data 
over short ranges; and extremely high-frequency (greater than 200 
kilohertz (kHz)) Doppler sonars used for navigation, like those used on 
commercial and private vessels. The characteristics of these sonars and 
other transducers, such as source level, beam width, directivity, and 
frequency, depend on the purpose of the source. Higher frequencies can 
carry more information or provide more information about objects off 
which they reflect, but attenuate more rapidly. Lower frequencies 
attenuate less rapidly, so they may detect objects over a longer 
distance, but with less detail.
    Additional detail regarding sound sources and platforms and 
categories of acoustic stressors was provided in our Federal Register 
notice of proposed rulemaking (85 FR 33914; June 2, 2020); please see 
that notice of proposed rulemaking or the Navy's application for more 
information.
    Sonars and other transducers are grouped into classes that share an 
attribute, such as frequency range or purpose of use. As detailed 
below, classes are further sorted by bins based on the frequency or 
bandwidth; source level; and, when warranted, the application in which 
the source would be used. Unless stated otherwise, a reference distance 
of 1 meter (m) is used for sonar and other transducers.
     Frequency of the non-impulsive acoustic source:
    [cir] Low-frequency sources operate below 1 kHz;
    [cir] Mid-frequency sources operate at and above 1 kHz, up to and 
including 10 kHz;
    [cir] High-frequency sources operate above 10 kHz, up to and 
including 100 kHz;
    [cir] Very-high-frequency sources operate above 100 kHz but below 
200 kHz;
     Sound pressure level of the non-impulsive source;
    [cir] Greater than 160 decibels (dB) re 1 micro Pascal ([micro]Pa), 
but less than 180 dB re: 1 [micro]Pa;
    [cir] Equal to 180 dB re: 1 [micro]Pa and up to 200 dB re: 1 
[micro]Pa;
    [cir] Greater than 200 dB re: 1 [micro]Pa;
     Application in which the source would be used:
    [cir] Sources with similar functions that have similar 
characteristics, such as pulse length (duration of each pulse), beam 
pattern, and duty cycle.
    The bins used for classifying active sonars and transducers that 
are quantitatively analyzed in the NWTT Study Area are shown in Table 1 
below. While general parameters or source characteristics are shown in 
the table, actual source parameters are classified.

[[Page 72316]]



Table 1--Sonar and Other Transducers Quantitatively Analyzed in the NWTT
                               Study Area
------------------------------------------------------------------------
      Source class category            Bin             Description
------------------------------------------------------------------------
Low-Frequency (LF): Sources that  LF4            LF sources equal to 180
 produce signals less than 1 kHz. LF5             dB and up to 200 dB.
                                                 LF sources less than
                                                  180 dB.
Mid-Frequency (MF): Tactical and  MF1            Hull-mounted surface
 non-tactical sources that                        ship sonars (e.g., AN/
 produce signals between 1 and                    SQS-53C and AN/SQS-
 10 kHz.                                          60).
                                  MF1K           Kingfisher mode
                                                  associated with MF1
                                                  sonars.
                                  MF2            Hull-mounted surface
                                                  ship sonars (e.g., AN/
                                                  SQS-56).
                                  MF3            Hull-mounted submarine
                                                  sonars (e.g., AN/BQQ-
                                                  10).
                                  MF4            Helicopter-deployed
                                                  dipping sonars (e.g.,
                                                  AN/AQS-22).
                                  MF5            Active acoustic
                                                  sonobuoys (e.g.,
                                                  DICASS).
                                  MF6            Underwater sound signal
                                                  devices (e.g., MK 84
                                                  SUS).
                                  MF9            Sources (equal to 180
                                                  dB and up to 200 dB)
                                                  not otherwise binned.
                                  MF10           Active sources (greater
                                                  than 160 dB, but less
                                                  than 180 dB) not
                                                  otherwise binned.
                                  MF11           Hull-mounted surface
                                                  ship sonars with an
                                                  active duty cycle
                                                  greater than 80
                                                  percent.
                                  MF12           Towed array surface
                                                  ship sonars with an
                                                  active duty cycle
                                                  greater than 80
                                                  percent.
High-Frequency (HF): Tactical     HF1            Hull-mounted submarine
 and non-tactical sources that    HF3             sonars (e.g., AN/BQQ-
 produce signals between 10 and                   10).
 100 kHz.                                        Other hull-mounted
                                                  submarine sonars
                                                  (classified).
                                  HF4            Mine detection,
                                                  classification, and
                                                  neutralization sonar
                                                  (e.g., AN/SQS-20).
                                  HF5            Active sources (greater
                                                  than 200 dB) not
                                                  otherwise binned.
                                  HF6            Sources (equal to 180
                                                  dB and up to 200 dB)
                                                  not otherwise binned.
                                  HF8            Hull-mounted surface
                                                  ship sonars (e.g., AN/
                                                  SQS-61).
                                  HF9            Weapon-emulating sonar
                                                  source.
Very High-Frequency (VHF):        VHF1           Active sources greater
 Tactical and non-tactical        VHF2            than 200 dB.
 sources that produce signals                    Active sources with a
 greater than 100 kHz but less                    source level less than
 than 200 kHz.                                    200 dB.
Anti-Submarine Warfare (ASW):     ASW1           MF systems operating
 Tactical sources (e.g., active   ASW2            above 200 dB.
 sonobuoys and acoustic           ASW3           MF Multistatic Active
 countermeasures systems) used    ASW4            Coherent sonobuoy
 during ASW training and testing  ASW5 \1\        (e.g., AN/SSQ-125).
 activities.                                     MF towed active
                                                  acoustic
                                                  countermeasure systems
                                                  (e.g., AN/SLQ-25).
                                                 MF expendable active
                                                  acoustic device
                                                  countermeasures (e.g.,
                                                  MK 3).
                                                 MF sonobuoys with high
                                                  duty cycles.
Torpedoes (TORP): Active          TORP1          Lightweight torpedo
 acoustic signals produced by                     (e.g., MK 46, MK 54,
 torpedoes.                                       or Anti-Torpedo
                                                  Torpedo).
                                  TORP2          Heavyweight torpedo
                                                  (e.g., MK 48).
                                  TORP3          Heavyweight torpedo
                                                  (e.g., MK 48).
Looking Sonar (FLS): Forward or   FLS2           HF sources with short
 upward looking object avoidance                  pulse lengths, narrow
 sonars used for ship navigation                  beam widths, and
 and safety.                                      focused beam patterns.
Acoustic Modems (M): Sources      M3             MF acoustic modems
 used to transmit data.                           (greater than 190 dB).
Synthetic Aperture Sonars (SAS):  SAS2           HF SAS systems.
 Sonars used to form high-
 resolution images of the
 seafloor.
Broadband Sound Sources (BB):     BB1            MF to HF mine
 Sonar systems with large         BB2             countermeasure sonar.
 frequency spectra, used for                     HF to VHF mine
 various purposes.                                countermeasure sonar.
------------------------------------------------------------------------
\1\ Formerly ASW2 in the 2015-2020 (Phase II) rulemaking.

Explosives
    This section describes the characteristics of explosions during 
naval training and testing. The activities analyzed in the Navy's 
rulemaking/LOA application that use explosives are described in 
additional detail in Appendix A (Training and Testing Activities 
Descriptions) of the 2020 NWTT FSEIS/OEIS. Explanations of the 
terminology and metrics used when describing explosives in the Navy's 
rule making/LOA application are also in Appendix H (Acoustic and 
Explosive Concepts) of the 2020 NWTT FSEIS/OEIS.
    The near-instantaneous rise from ambient to an extremely high peak 
pressure is what makes an explosive shock wave potentially damaging. 
Farther from an explosive, the peak pressures decay and the explosive 
waves propagate as an impulsive, broadband sound. Several parameters 
influence the effect of an explosive: The weight of the explosive in 
the warhead, the type of explosive material, the boundaries and 
characteristics of the propagation medium, and, in water, the 
detonation depth and the depth of the receiver (i.e., marine mammal). 
The net explosive weight, which is the explosive power of a charge 
expressed as the equivalent weight of trinitrotoluene (TNT), accounts 
for the first two parameters. The effects of these factors are 
explained in Appendix D (Acoustic and Explosive Concepts) of the 2020 
NWTT FSEIS/OEIS. The activities analyzed in the Navy's rulemaking/LOA 
application and this final rule that use explosives are described in 
further detail in Appendix A (Navy Activities Descriptions) of the 2020 
NWTT FSEIS/OEIS. Explanations of the terminology and metrics used when 
describing explosives are provided in Appendix D (Acoustic and 
Explosive Concepts) of the 2020 NWTT FSEIS/OEIS.
    Explosive detonations during training and testing activities are 
associated with high-explosive munitions, including,

[[Page 72317]]

but not limited to, bombs, missiles, naval gun shells, torpedoes, 
mines, demolition charges, and explosive sonobuoys. Explosive 
detonations during training and testing involving the use of high-
explosive munitions (including bombs, missiles, and naval gun shells) 
could occur in the air or near the water's surface. Explosive 
detonations associated with torpedoes and explosive sonobuoys would 
occur in the water column; mines and demolition charges could be 
detonated in the water column or on the ocean bottom. Most detonations 
will occur in waters greater than 200 ft in depth, and greater than 50 
nmi from shore, with the exception of Mine Countermeasure and 
Neutralization testing planned in the Offshore Area, and existing mine 
warfare training areas in Inland Waters (i.e., Crescent Harbor and Hood 
Canal Explosive Ordnance Disposal Training Ranges). Mine countermeasure 
and neutralization testing is a new planned testing activity that would 
occur closer to shore than other in-water explosive activities analyzed 
in the 2015 NWTT Final EIS/OEIS for the Offshore Area of the NWTT Study 
Area. This activity would occur in waters 3 nmi or greater from shore 
in the Quinault Range Site (outside the Olympic Coast National Marine 
Sanctuary), or 12 nmi or greater from shore elsewhere in the Offshore 
Area, and will not occur off the coast of California. Since publication 
of the proposed rule, the Navy has agreed that it will conduct 
explosive Mine Countermeasure and Neutralization testing in daylight 
hours only, and in Beaufort Sea state number 3 conditions or less. Two 
of the three events would involve the use of explosives, and would 
typically occur in water depths shallower than 1,000 ft. The two multi-
day events (1-10 days per event) would include up to 36 E4 explosives 
(>2.5-5 lb net explosive weight) and 5 E7 explosives (>20-60 lb net 
explosive weight). Use of E7 explosives would occur greater than 6 nmi 
from shore. Since publication of the proposed rule, the Navy has agreed 
that, within 20 nmi from shore in the Marine Species Coastal Mitigation 
Area, the Navy will conduct no more than one Mine Countermeasure and 
Neutralization testing event annually, not to exceed the use of 20 E4 
and 3 E7 explosives, from October 1 through June 30. Additionally, 
within 20 nmi from shore in the Marine Species Coastal Mitigation Area, 
the Navy will not exceed 60 E4 and 9 E7 explosives over seven years, 
from October 1 through June 30. Finally, to the maximum extent 
practical, the Navy will conduct explosive Mine Countermeasure and 
Neutralization Testing from July 1 through September 30 when operating 
within 20 nmi from shore in the Marine Species Coastal Mitigation Area. 
In order to better organize and facilitate the analysis of explosives 
used by the Navy during training and testing that could detonate in 
water or at the water surface, explosive classification bins were 
developed. The use of explosive classification bins provides the same 
benefits as described for acoustic source classification bins discussed 
above and in Section 1.4.1 (Acoustic Stressors) of the Navy's 
rulemaking/LOA application.
    Explosives detonated in water are binned by net explosive weight. 
The bins of explosives in the NWTT Study Area are shown in Table 2 
below.

           Table 2--Explosives Analyzed in the NWTT Study Area
------------------------------------------------------------------------
                                  Net explosive     Example explosive
              Bin                  weight (lb)            source
------------------------------------------------------------------------
E1.............................        0.1-0.25  Medium-caliber
                                                  projectiles.
E2.............................       >0.25-0.5  Medium-caliber
                                                  projectiles.
E3.............................        >0.5-2.5  Explosive Ordnance
                                                  Disposal Mine
                                                  Neutralization.
E4.............................          >2.5-5  Mine Countermeasure and
                                                  Neutralization.
E5.............................           >5-10  Large-caliber
                                                  projectile.
E7.............................          >20-60  Mine Countermeasure and
                                                  Neutralization.
E8.............................         >60-100  Lightweight torpedo.
E10............................        >250-500  1,000 lb bomb.
E11............................        >500-650  Heavyweight torpedo.
------------------------------------------------------------------------

    Propagation of explosive pressure waves in water is highly 
dependent on environmental characteristics such as bathymetry, bottom 
type, water depth, temperature, and salinity, which affect how the 
pressure waves are reflected, refracted, or scattered; the potential 
for reverberation; and interference due to multi-path propagation. In 
addition, absorption greatly affects the distance over which higher-
frequency components of explosive broadband noise can propagate. 
Appendix D (Acoustic and Explosive Concepts) of the 2020 NWTT FSEIS/
OEIS explains the characteristics of explosive detonations and how the 
above factors affect the propagation of explosive energy in the water.
    Marine mammals could be exposed to fragments from underwater 
explosions associated with the specified activities. When explosive 
ordnance (e.g., bomb or missile) detonates, fragments of the weapon are 
thrown at high-velocity from the detonation point, which can injure or 
kill marine mammals if they are struck. These fragments may be of 
variable size and are ejected at supersonic speed from the detonation. 
The casing fragments will be ejected at velocities much greater than 
debris from any target due to the proximity of the casing to the 
explosive material. Risk of fragment injury reduces exponentially with 
distance as the fragment density is reduced. Fragments underwater tend 
to be larger than fragments produced by in-air explosions (Swisdak and 
Montaro, 1992). Underwater, the friction of the water would quickly 
slow these fragments to a point where they no longer pose a threat. 
Opposingly, the blast wave from an explosive detonation moves 
efficiently through the seawater. Because the ranges to mortality and 
injury due to exposure to the blast wave are likely to far exceed the 
zone where fragments could injure or kill an animal, the thresholds and 
associated ranges for assessing the likelihood of mortality and injury 
from a blast, which are also used to inform mitigation zones, are 
assumed to encompass risk due to fragmentation.

Other Stressor--Vessel Strike

    Vessel strikes are not specific to any particular training or 
testing activity, but rather a potential, limited, sporadic, and 
incidental result of Navy vessel movement within the NWTT Study Area. 
Navy vessels transit at speeds that are optimal for fuel conservation 
or to meet training and testing requirements. Should a vessel strike 
occur, it would likely result in incidental take from

[[Page 72318]]

serious injury and/or mortality and, accordingly, for the purposes of 
the analysis we assume that any authorized ship strike would result in 
serious injury or mortality. Information on Navy vessel movement is 
provided in the Vessel Movement section of this rule. Additional detail 
on vessel strike was provided in our Federal Register notice of 
proposed rulemaking (85 FR 33914; June 2, 2020); please see that notice 
of proposed rulemaking or the Navy's application for more information.

Detailed Description of Specified Activities

Planned Training and Testing Activities

    The Navy's Operational Commands and various System Commands have 
identified activity levels that are needed in the NWTT Study Area to 
ensure naval forces have sufficient training, maintenance, and new 
technology to meet Navy missions in the Northwest. Training prepares 
Navy personnel to be proficient in safely operating and maintaining 
equipment, weapons, and systems to conduct assigned missions. Navy 
research develops new science and technology followed by concept 
testing relevant to future Navy needs.
    The training and testing activities that the Navy plans to conduct 
in the NWTT Study Area are summarized in Table 3 (training) and Table 4 
(testing). The tables are organized according to primary mission areas 
and include the activity name, associated stressor(s), description of 
the activity, sound source bin, the locations of those activities in 
the NWTT Study Area, and the number of activities. For further 
information regarding the primary platform used (e.g., ship or aircraft 
type) see Appendix A (Training and Testing Activities Descriptions) of 
the 2020 NWTT FSEIS/OEIS.
    This section indicates the number of activities that could occur 
each year and then the maximum total that could occur over seven years. 
When a range of annual activities is provided, the maximum number is 
analyzed. The maximum number of activities may occur during some years, 
but not others, as several activities--Torpedo Exercise-Submarine 
Training, Tracking Exercise- Helicopter Training, Civilian Port 
Defense- Homeland Security Anti-Terrorism/Force Protection Training, 
Bomb Exercise Training, and Missile Exercise Training--do not occur 
every year, and other activities may occur every year, but less 
frequently than the maximum annual total. However, to conduct a 
conservative analysis, NMFS analyzed the maximum times these activities 
could occur over one year and seven years, with the assumption that 
this number of activities would be representative of the annual and 
seven-year activity totals.

                                 Table 3--Training Activities Analyzed for the Seven-Year Period in the NWTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                 7-Year
                                                                      Typical                                                                    number
   Stressor category        Activity           Description          duration of       Source bin         Location      Annual number of events     of
                                                                       event                                                                     events
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Anti-Submarine Warfare
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic; Explosive...  Torpedo           Submarine crews        8 hours.........  TORP2...........  Offshore Area                         0-2         5
                         Exercise--Subma   search for, track,                                         >12 nmi from
                         rine (TORPEX--    and detect                                                 land.
                         Sub).             submarines. Event
                                           would include one MK-
                                           48 torpedo used
                                           during this event.
Acoustic..............  Tracking          Helicopter crews       2-4 hours.......  MF4, MF5........  Offshore Area                         0-2         5
                         Exercise -        search for, track,                                         >12 nmi from
                         Helicopter        and detect                                                 land.
                         (TRACKEX--Helo).  submarines.
Acoustic..............  Tracking          Maritime patrol        2-8 hours.......  ASW2, ASW5, MF5,  Offshore Area                         373     2,611
                         Exercise--Marit   aircraft crews                           TORP1.            >12 nmi from
                         ime Patrol        search for, track,                                         land.
                         Aircraft          and detect
                         (TRACKEX--MPA).   submarines.
Acoustic..............  Tracking          Surface ship crews     2-4 hours.......  ASW3, MF1, MF11.  Offshore Area...                       62       434
                         Exercise -Ship    search for, track,
                         (TRACKEX--Ship).  and detect
                                           submarines.
Acoustic..............  Tracking          Submarine crews        8 hours.........  HF1, MF3........  Offshore Area...                   75-100       595
                         Exercise--Subma   search for, track,
                         rine (TRACKEX--   and detect
                         Sub).             submarines.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Mine Warfare
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic..............  Civilian Port     Maritime security      Multiple days...  HF4, SAS2.......  Inland Waters...                      0-1         5
                         Defense--Homela   personnel train to
                         nd Security       protect civilian
                         Anti-Terrorism/   ports and harbors
                         Force             against enemy
                         Protection        efforts to interfere
                         Exercises.        with access to those
                                           ports..
Explosive.............  Mine              Personnel disable      Up to 4 hours...  E3..............  Crescent Harbor                     \1\ 6    \1\ 42
                         Neutralization-   threat mines using                                         EOD Training
                         -Explosive        explosive charges.                                         Range, Hood
                         Ordnance                                                                     Canal EOD
                         Disposal (EOD).                                                              Training Range.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                     Surface Warfare
--------------------------------------------------------------------------------------------------------------------------------------------------------
Explosive.............  Bombing Exercise  Fixed-wing aircrews    1 hour..........  E10.............  Offshore Area (W-    0-2 (counts only the         5
                         (Air-to-          deliver bombs                                              237) > 50 nmi          explosive events)
                         Surface)(BOMBEX   against surface                                            from land.
                         [A-S]).           targets.
Explosive.............  Gunnery Exercise  Surface ship crews     Up to 3 hours...  E1, E2, E5......  Offshore Area >   \1\ 34 (counts only the   \1\ 238
                         (Surface-to-      fire large- and                                            50 nmi from            explosive events)
                         Surface)--Ship    medium-caliber guns                                        land.
                         (GUNEX [S-S]--    at surface targets..
                         Ship).
Explosive.............  Missile Exercise  Fixed-wing aircrews    2 hours.........  E10.............  Offshore Area (W-                     0-2         5
                         (Air-to-          simulate firing                                            237) > 50 nmi
                         Surface)(MISSIL   precision-guided                                           from land.
                         EX [A-S]).        missiles, using
                                           captive air training
                                           missiles (CATMs)
                                           against surface
                                           targets. Some
                                           activities include
                                           firing a missile
                                           with a high-
                                           explosive (HE)
                                           warhead..
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                     Other Training
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic..............  Submarine Sonar   Maintenance of         Up to 1 hour....  LF5, MF3, HF1...  NBK Bangor, NBK                        26       182
                         Maintenance.      submarine sonar and                                        Bremerton, and
                                           other system checks                                        Offshore Area
                                           are conducted                                              >12 nmi from
                                           pierside or at sea..                                       land.
Acoustic..............  Surface Ship      Maintenance of         Up to 4 hours...  MF1.............  NBK Bremerton,                         25       175
                         Sonar             surface ship sonar                                         NS Everett, and
                         Maintenance.      and other system                                           Offshore Area
                                           checks are conducted                                       >12 nmi from
                                           pierside or at sea..                                       land.

[[Page 72319]]

 
Acoustic..............  Unmanned          Unmanned underwater    Up to 24 hours..  FLS2, M3........  Inland Waters,                         60       420
                         Underwater        vehicle                                                    Offshore Area.
                         Vehicle           certification
                         Training.         involves training
                                           with unmanned
                                           platforms to ensure
                                           submarine crew
                                           proficiency.
                                           Tactical development
                                           involves training
                                           with various
                                           payloads for
                                           multiple purposes to
                                           ensure that the
                                           systems can be
                                           employed effectively
                                           in an operational
                                           environment..
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ These activities have been reduced since publication of the proposed rule.


                                  Table 4--Testing Activities Analyzed for the Seven-Year Period in the NWTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                 7-Year
                                                                      Typical                                                                    number
   Stressor category        Activity           Description           duration         Source bin         Location      Annual number of events     of
                                                                                                                                                 events
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Naval Sea Systems Command Testing Activities
                                                                 Anti-Submarine Warfare
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic..............  Anti-Submarine    Ships and their        4-8 hours of      ASW1, ASW2,       Offshore Area...                       44       308
                         Warfare Testing.  supporting platforms   active sonar      ASW3, ASW5,
                                           (rotary-wing           use.              MF1K, MF4, MF5,
                                           aircraft and                             MF10, MF11,
                                           unmanned aerial                          MF12, TORP1.
                                           systems) detect,
                                           localize, and
                                           prosecute submarines.
Acoustic..............  At-Sea Sonar      At-sea testing to      From 4 hours to   ASW3, HF1, HF5,   Offshore Area...                        4        28
                         Testing.          ensure systems are     11 days.          M3, MF3,.        ................  .......................  ........
                                           fully functional in                     ASW3, HF5, TORP1  ................  .......................  ........
                                           an open ocean                                             ................  .......................  ........
                                           environment..                                             Inland Waters                         4-6        34
                                                                                                      (DBRC).
Acoustic..............  Countermeasure    Countermeasure         From 4 hours to   ASW3, ASW4, HF8,  Offshore Area                          14        98
                         Testing.          testing involves the   6 days.           MF1, TORP2.       (QRS).           .......................  ........
                                           testing of systems                      ASW3, ASW4......  ................  .......................  ........
                                           that will detect,                       ASW4............  ................  .......................  ........
                                           localize, and track                                       ................  .......................  ........
                                           incoming weapons,                                         ................                       29       203
                                           including marine                                          Inland Waters     .......................  ........
                                           vessel targets.                                            (DBRC, Keyport                         1         5
                                           Countermeasures may                                        Range Site).
                                           be systems to                                             Western Behm
                                           obscure the vessel's                                       Canal, AK.
                                           location or systems
                                           to rapidly detect,
                                           track, and counter
                                           incoming threats.
                                           Testing includes
                                           surface ship torpedo
                                           defense systems and
                                           marine vessel
                                           stopping payloads.
Acoustic..............  Pierside-Sonar    Pierside testing to    Up to 3 weeks...  ASW3, HF3, MF1,   Inland Waters                       88-99       635
                         Testing.          ensure systems are                       MF2, MF3, MF9,    (NS Everett,
                                           fully functional in                      MF10, MF12.       NBK Bangor, NBK
                                           a controlled                                               Bremerton).
                                           pierside environment
                                           prior to at-sea test
                                           activities.
Acoustic..............  Submarine Sonar   Pierside, moored, and  Up to 3 weeks...  HF6, MF9........  Western Behm                          1-2        10
                         Testing/          underway testing of                                        Canal, AK.
                         Maintenance.      submarine systems
                                           occurs periodically
                                           following major
                                           maintenance periods
                                           and for routine
                                           maintenance.
Acoustic; Explosive...  Torpedo           Air, surface, or       1-2 hours during  E8, E11, ASW3,    Offshore Area>                          4        28
                         (Explosive)       submarine crews        daylight only.    HF1, HF6, MF1,    50 nmi from
                         Testing.          employ explosive and                     MF3, MF4, MF5,    land.
                                           non-explosive                            MF6, TORP1,
                                           torpedoes against                        TORP2.
                                           artificial targets.
Acoustic..............  Torpedo (Non-     Air, surface, or       Up to 2 weeks...  ASW3, ASW4, HF1,  Offshore Area...                       22       154
                         explosive)        submarine crews                          HF5, HF6, MF1,   ................  .......................  ........
                         Testing.          employ non-explosive                     MF3, MF4, MF5,   ................  .......................  ........
                                           torpedoes against                        MF6, MF9, MF10,  ................  .......................  ........
                                           targets, submarines,                     TORP1, TORP2.    ................  .......................  ........
                                           or surface vessels..                    HF6, LF4, TORP1,  ................  .......................  ........
                                                                                    TORP2, TORP3.    ................  .......................  ........
                                                                                                     ................  .......................  ........
                                                                                                     ................  .......................  ........
                                                                                                     ................  .......................  ........
                                                                                                     ................  .......................  ........
                                                                                                     ................  .......................  ........
                                                                                                     ................  .......................  ........
                                                                                                     ................  .......................  ........
                                                                                                     Inland Waters                          61       427
                                                                                                      (DBRC).
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 72320]]

 
                                                                      Mine Warfare
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic; Explosive...  Mine              Air, surface, and      1-10 days.......  E4, E7, HF4.....  Offshore Area...                    \1\ 2     \1\ 6
                         Countermeasure    subsurface vessels                      HF4.............  ................  .......................  ........
                         and               neutralize threat                                         Inland Waters...                        3        13
                         Neutralization    mines and mine-like
                         Testing.          objects..
Acoustic..............  Mine Detection    Air, surface, and      Up to 24 days...  BB1, BB2, LF4...  Offshore Area                           1         7
                         and               subsurface vessels                      BB1, BB2, HF4,     (QRS).           .......................  ........
                         Classification    and systems detect                       LF4.             ................                       42       294
                         Testing.          and classify mines                                        Inland Waters
                                           and mine-like                                              (DBRC, Keyport
                                           objects. Vessels                                           Range Site).
                                           also assess their
                                           potential
                                           susceptibility to
                                           mines and mine-like
                                           objects..
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Unmanned Systems
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic..............  Unmanned          Testing involves the   Typically 1-2     FLS2, HF5,        Offshore Area                       38-39       269
                         Underwater        production or          days, up to       TORP1, VHF1.      (QRS).           .......................  ........
                         Vehicle Testing.  upgrade of unmanned    multiple months. DS3, FLS2, HF5,   ................  .......................  ........
                                           underwater vehicles.                     HF9, M3, SAS2,   ................                  371-379     2,615
                                           This may include                         VHF1, TORP1.     Inland Waters
                                           testing of mission                                         (DBRC, Keyport
                                           capabilities (e.g.,                                        Range Site,
                                           mine detection),                                           Carr Inlet).
                                           evaluating the basic
                                           functions of
                                           individual
                                           platforms, or
                                           conducting complex
                                           events with multiple
                                           vehicles..
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Vessel Evaluation
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic..............  Undersea Warfare  Ships demonstrate      Up to 10 days...  ASW3, ASW4, HF4,  Offshore Area...                     1-12        27
                         Testing.          capability of                            MF1, MF4, MF5,
                                           countermeasure                           MF6, MF9,
                                           systems and                              TORP1, TORP2.
                                           underwater
                                           surveillance,
                                           weapons engagement,
                                           and communications
                                           systems. This tests
                                           ships' ability to
                                           detect, track, and
                                           engage undersea
                                           targets..
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Other Testing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic..............  Acoustic and      Research using active  Up to 14 days...  LF4, MF9........  Offshore Area                           1         7
                         Oceanographic     transmissions from                                         (QRS).                                 3        21
                         Research.         sources deployed                                          Inland Waters
                                           from ships,                                                (DBRC, Keyport
                                           aircraft, and                                              Range Site).
                                           unmanned underwater
                                           vehicles. Research
                                           sources can be used
                                           as proxies for
                                           current and future
                                           Navy systems..
Acoustic..............  Acoustic          Various surface        1 day to          HF3, HF6, LF5,    Western Behm                        13-18        99
                         Component         vessels, moored        multiple months.  MF9.              Canal, AK.
                         Testing.          equipment, and
                                           materials are tested
                                           to evaluate
                                           performance in the
                                           marine environment.
Acoustic..............  Cold Water        Fleet training for     8 hours.........  HF6.............  Inland Waters                           4        28
                         Support.          divers in a cold                                           (Keyport Range   .......................  ........
                                           water environment,                                         Site, DBRC,      .......................  ........
                                           and other diver                                            Carr Inlet).                           1         7
                                           training related to                                       Western Behm
                                           Navy divers                                                Canal, AK.
                                           supporting range/
                                           test site operations
                                           and maintenance..
Acoustic..............  Post-Refit Sea    Following periodic     8 hours.........  HF9, M3, MF10...  Inland Waters                          30       210
                         Trial.            maintenance periods                                        (DBRC).
                                           or repairs, sea
                                           trials are conducted
                                           to evaluate
                                           submarine
                                           propulsion, sonar
                                           systems, and other
                                           mechanical tests..
Acoustic..............  Semi-Stationary   Semi-stationary        From 10 minutes   HF6, HF9, LF4,    Inland Waters                         120       840
                         Equipment         equipment (e.g.,       to multiple       MF9, VHF2.        (DBRC, Keyport   .......................  ........
                         Testing.          hydrophones) is        days.            HF6, HF9........   Range Site).     .......................  ........
                                           deployed to                                               ................  .......................  ........
                                           determine                                                 ................                      2-3        12
                                           functionality..                                           Western Behm
                                                                                                      Canal, AK.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Naval Air Systems Command Testing Activities
                                                                 Anti-Submarine Warfare
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic; Explosive...  Tracking Test--   The test evaluates     4-8 flight hours  E1, E3, ASW2,     Offshore Area...                        8        56
                         Maritime Patrol   the sensors and                          ASW5, MF5, MF6.
                         Aircraft.         systems used by
                                           maritime patrol
                                           aircraft to detect
                                           and track submarines
                                           and to ensure that
                                           aircraft systems
                                           used to deploy the
                                           tracking systems
                                           perform to
                                           specifications and
                                           meet operational
                                           requirements..
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ In the proposed rule, NMFS analyzed three events annually, and 15 events over the seven-year period; however, only two of the three annual events
  include sonar and/or explosives. The third annual event does not have acoustic components, and therefore, is not included here in the final rule.
  Additionally, the seven-year number of events has been reduced since publication of the proposed rule.

Summary of Acoustic and Explosive Sources Analyzed for Training and 
Testing

    Tables 5 through 8 show the acoustic and explosive source classes, 
bins, and quantities used in either hours or counts associated with the 
Navy's training and testing activities over a seven-year period in the 
NWTT Study Area that were analyzed in the Navy's rulemaking/LOA 
application and by NMFS through the rulemaking process. Table 5 
describes the acoustic source classes (i.e., low-frequency (LF), mid-
frequency (MF), and high-frequency (HF)) that could occur over seven 
years under the planned training activities. Acoustic source bin use in 
the proposed activities will vary annually. The seven-year totals for 
the planned training activities take into account that annual 
variability.

[[Page 72321]]



  Table 5--Acoustic Source Classes Analyzed and Usage for Seven-Year Period for Training Activities in the NWTT
                                                   Study Area
----------------------------------------------------------------------------------------------------------------
                                                                                                        7-year
       Source class category                Bin             Description       Unit \1\     Annual       total
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF): Sources that     LF5               LF sources less than         H             1            5
 produce signals less than 1 kHz.                       180 dB.
Mid-Frequency (MF): Tactical and     MF1               Hull-mounted surface         H           164        1,148
 non-tactical sources that produce                      ship sonars (e.g.,
 signals between 1 and 10 kHz.                          AN/SQS-53C and AN/
                                                        SQS-61).
                                     MF3               Hull-mounted                 H            70          490
                                                        submarine sonars
                                                        (e.g., AN/BQQ-10).
                                     MF4               Helicopter-deployed          H           0-1            1
                                                        dipping sonars
                                                        (e.g., AN/AQS-22 and
                                                        AN/AQS-13).
                                     MF5               Active acoustic               C      918-926        6,443
                                                        sonobuoys (e.g.,
                                                        DICASS).
                                     MF11              Hull-mounted surface         H            16          112
                                                        ship sonars with an
                                                        active duty cycle
                                                        greater than 80%.
High-Frequency (HF): Tactical and    HF1               Hull-mounted                 H            48          336
 non-tactical sources that produce                      submarine sonars
 signals between 10 and 100 kHz.                        (e.g., AN/BQQ-10).
                                     HF4               Mine detection,              H          0-65          269
                                                        classification, and
                                                        neutralization sonar
                                                        (e.g., AN/SQS-20).
Anti-Submarine Warfare (ASW):        ASW2              MF Multistatic Active         C          350        2,450
 Tactical sources (e.g., active                         Coherent sonobuoy
 sonobuoys and acoustic                                 (e.g., AN/SSQ-125).
 countermeasures systems) used
 during ASW training and testing
 activities.
                                     ASW3              MF towed active              H            86          602
                                                        acoustic
                                                        countermeasure
                                                        systems (e.g., AN/
                                                        SLQ-25).
                                     ASW5              MF sonobuoys with            H            50          350
                                                        high duty cycles.
Torpedoes (TORP): Source classes     TORP1             Lightweight torpedo           C           16          112
 associated with the active                             (e.g., MK 46, MK 54,
 acoustic signals produced by                           or Anti-Torpedo
 torpedoes.                                             Torpedo).
                                     TORP2             Heavyweight torpedo           C          0-2            5
                                                        (e.g., MK 48).
Forward Looking Sonar (FLS):         FLS2              HF sources with short        H           240        1,680
 Forward or upward looking object                       pulse lengths,
 avoidance sonars used for ship                         narrow beam widths,
 navigation and safety.                                 and focused beam
                                                        patterns.
Acoustic Modems (M): Systems used    M3                MF acoustic modems           H            30          210
 to transmit data through the water.                    (greater than 190
                                                        dB).
Synthetic Aperture Sonars (SAS):     SAS2              HF SAS systems.......        H         0-561        2,353
 Sonars in which active acoustic
 signals are post-processed to form
 high-resolution images of the
 seafloor.
----------------------------------------------------------------------------------------------------------------
\1\ H = hours; C = count.

    Table 6 describes the acoustic source classes and numbers that 
could occur over seven years under the planned testing activities. 
Acoustic source bin use in the planned activities would vary annually. 
The seven-year totals for the planned testing activities take into 
account that annual variability.

  Table 6--Acoustic Source Classes Analyzed and Usage for Seven-Year Period for Testing Activities in the NWTT
                                                   Study Area
----------------------------------------------------------------------------------------------------------------
                                                                                                        7-year
       Source class category                Bin             Description       Unit \1\     Annual       total
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF): Sources that     LF4               LF sources equal to          H           177        1,239
 produce signals less than 1 kHz.                       180 dB and up to 200
                                                        dB.
                                     LF5               LF sources less than         H          0-18           23
                                                        180 dB.
Mid-Frequency (MF): Tactical and     MF1               Hull-mounted surface         H        20-169          398
 non-tactical sources that produce                      ship sonars (e.g.,
 signals between 1 and 10 kHz.                          AN/SQS-53C and AN/
                                                        SQS-61).
                                     MF1K              Kingfisher mode              H            48          336
                                                        associated with MF1
                                                        sonars.
                                     MF2               Hull-mounted surface         H            32          224
                                                        ship sonars (e.g.,
                                                        AN/SQS-56).
                                     MF3               Hull-mounted                 H         34-36          239
                                                        submarine sonars
                                                        (e.g., AN/BQQ-10).
                                     MF4               Helicopter-deployed          H         41-50          298
                                                        dipping sonars
                                                        (e.g., AN/AQS-22 and
                                                        AN/AQS-13).
                                     MF5               Active acoustic               C      300-673        2,782
                                                        sonobuoys (e.g.,
                                                        DICASS).
                                     MF6               Active underwater             C       60-232          744
                                                        sound signal devices
                                                        (e.g., MK 84 SUS).
                                     MF9               Active sources (equal        H       644-959        5,086
                                                        to 180 dB and up to
                                                        200 dB) not
                                                        otherwise binned.
                                     MF10              Active sources               H           886        6,197
                                                        (greater than 160
                                                        dB, but less than
                                                        180 dB) not
                                                        otherwise binned.

[[Page 72322]]

 
                                     MF11              Hull-mounted surface         H            48          336
                                                        ship sonars with an
                                                        active duty cycle
                                                        greater than 80
                                                        percent.
                                     MF12              Towed array surface          H           100          700
                                                        ship sonars with an
                                                        active duty cycle
                                                        greater than 80
                                                        percent.
High-Frequency (HF): Tactical and    HF1               Hull-mounted                 H            10           68
 non-tactical sources that produce                      submarine sonars
 signals between 10 and 100 kHz.                        (e.g., AN/BQQ-10).
                                     HF3               Other hull-mounted           H          1-19           30
                                                        submarine sonars
                                                        (classified).
                                     HF4               Mine detection,              H   1,860-1,868       11,235
                                                        classification, and
                                                        neutralization sonar
                                                        (e.g., AN/SQS-20).
                                     HF5               Active sources               H       352-400        2,608
                                                        (greater than 200
                                                        dB) not otherwise
                                                        binned.
                                     HF6               Active sources (equal        H   1,705-1,865       12,377
                                                        to 180 dB and up to
                                                        200 dB) not
                                                        otherwise binned.
                                     HF8               Hull-mounted surface         H            24          168
                                                        ship sonars (e.g.,
                                                        AN/SQS-61).
                                     HF9               Weapon emulating             H           257        1,772
                                                        sonar source.
Very High-Frequency (VHF): Tactical  VHF1              Very high frequency          H           320        2,240
 and non-tactical sources that                          sources greater than
 produce signals greater than 100                       200 dB.
 kHz but less than 200 kHz.
                                     VHF2              Active sources with a        H           135          945
                                                        frequency greater
                                                        than 100 kHz, up to
                                                        200 kHz with a
                                                        source level less
                                                        than 200 dB.
Anti-Submarine Warfare (ASW):        ASW1              MF systems operating         H            80          560
 Tactical sources (e.g., active                         above 200 dB.
 sonobuoys and acoustic
 countermeasures systems) used
 during ASW training and testing
 activities.
                                     ASW2              MF systems operating          C          240        1,680
                                                        above 200 dB.
                                     ASW3              MF towed active              H     487-1,015        4,091
                                                        acoustic
                                                        countermeasure
                                                        systems (e.g., AN/
                                                        SLQ-25).
                                     ASW4              MF expendable active          C  1,349-1,389        9,442
                                                        acoustic device
                                                        countermeasures
                                                        (e.g., MK 3).
                                     ASW5              MF sonobuoys with            H            80          560
                                                        high duty cycles.
Torpedoes (TORP): Source classes     TORP1             Lightweight torpedo           C      298-360        2,258
 associated with the active                             (e.g., MK 46, MK 54,
 acoustic signals produced by                           or Anti-Torpedo
 torpedoes.                                             Torpedo).
                                     TORP2             Heavyweight torpedo           C      332-372        2,324
                                                        (e.g., MK 48).
                                     TORP3             Heavyweight torpedo           C            6           42
                                                        test (e.g., MK 48).
Forward Looking Sonar (FLS):         FLS2              HF sources with short        H            24          168
 Forward or upward looking object                       pulse lengths,
 avoidance sonars used for ship                         narrow beam widths,
 navigation and safety.                                 and focused beam
                                                        patterns.
Acoustic Modems (M): Systems used    M3                MF acoustic modems           H         1,088        7,616
 to transmit data through the water.                    (greater than 190
                                                        dB).
Synthetic Aperture Sonars (SAS):     SAS2              HF SAS systems.......        H         1,312        9,184
 Sonars in which active acoustic
 signals are post-processed to form
 high-resolution images of the
 seafloor.
Broadband Sound Sources (BB): Sonar  BB1               MF to HF mine                H            48          336
 systems with large frequency                           countermeasure sonar.
 spectra, used for various purposes.
                                     BB2               HF to VHF mine               H            48          336
                                                        countermeasure sonar.
----------------------------------------------------------------------------------------------------------------
\1\ H = hours; C = count.

    Table 7 describes the number of in-water explosives that could be 
used in any year under the planned training activities. Under the 
planned activities, bin use will vary annually, and the seven-year 
totals for the planned training activities take into account that 
annual variability.

 Table 7--Explosive Source Class Bins Analyzed and Number of Detonations Used for Seven-Year Period for Training
                                        Activities in the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
                                         Net explosive
                  Bin                     weight \1\    Example explosive source    Annual \3\     7-year total
                                           (lb) \2\
----------------------------------------------------------------------------------------------------------------
E1....................................        0.1-0.25  Medium-caliber                    60-120             672
                                                         projectiles.
E2....................................       >0.25-0.5  Medium-caliber                    65-130             728
                                                         projectiles.
E3....................................        >0.5-2.5  Explosive Ordnance                     6              42
                                                         Disposal Mine
                                                         Neutralization.
E5....................................           >5-10  Large-caliber projectile          56-112             628

[[Page 72323]]

 
E10...................................        >250-500  1,000 lb bomb...........             0-4               9
----------------------------------------------------------------------------------------------------------------
\1\ Net explosive weight refers to the equivalent amount of TNT. The actual weight of a munition may be larger
  due to other components.
\2\ lb = pound(s).
\3\ Annual Nominal--Max. Two values indicate a range from Nominal to Max annual totals.

    Table 8 describes the number of in-water explosives that could be 
used in any year under the planned testing activities. Under the 
planned activities, bin use will vary annually, and the seven-year 
totals for the planned testing activities take into account that annual 
variability.

 Table 8--Explosive Source Class Bins Analyzed and Number of Detonations Used for Seven-Year Period for Testing
                                        Activities in the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
                                         Net explosive
                  Bin                     weight \1\    Example explosive source    Annual \3\     7-year total
                                           (lb) \2\
----------------------------------------------------------------------------------------------------------------
E1....................................        0.1-0.25  SUS buoy................               8              56
E3....................................        >0.5-2.5  Explosive sonobuoy......              72             504
E4....................................          >2.5-5  Mine Countermeasure and               36             108
                                                         Neutralization.
E7....................................          >20-60  Mine Countermeasure and                5              15
                                                         Neutralization.
E8....................................         >60-100  Lightweight torpedo.....               4              28
E11...................................        >500-650  Heavyweight torpedo.....               4              28
----------------------------------------------------------------------------------------------------------------
\1\ Net explosive weight refers to the equivalent amount of TNT. The actual weight of a munition may be larger
  due to other components.
\2\ lb = pound(s).
\3\ Annual Nominal--Max.

Vessel Movement

    Vessels used as part of the planned activities include ships, 
submarines, unmanned vessels, and boats ranging in size from small, 22 
ft rigid hull inflatable boats to aircraft carriers with lengths up to 
1,092 ft. Large ships greater than 60 ft generally operate at speeds in 
the range of 10-15 kn for fuel conservation. Submarines generally 
operate at speeds in the range of 8-13 kn in transits and less than 
those speeds for certain tactical maneuvers. Small craft (for purposes 
of this discussion--less than 60 ft in length) have much more variable 
speeds (dependent on the mission). While these speeds are 
representative of most events, some vessels need to temporarily operate 
outside of these parameters. For example, to produce the required 
relative wind speed over the flight deck, an aircraft carrier engaged 
in flight operations must adjust its speed through the water 
accordingly. Conversely, there are other instances, such as launch and 
recovery of a small rigid hull inflatable boat; vessel boarding, 
search, and seizure training events; or retrieval of a target when 
vessels will be dead in the water or moving slowly ahead to maintain 
steerage.
    The number of military vessels used in the NWTT Study Area varies 
based on military training and testing requirements, deployment 
schedules, annual budgets, and other unpredictable factors. Many 
training and testing activities involve the use of vessels. These 
activities could be widely dispersed throughout the NWTT Study Area, 
but will be typically conducted near naval ports, piers, and range 
areas. Training and testing activities involving vessel movements occur 
intermittently and are variable in duration, ranging from a few hours 
to up to two weeks. There is no seasonal differentiation in military 
vessel use. Large vessel movement primarily occurs with the majority of 
the traffic flowing between the installations and the Operating Areas 
(OPAREAS). Smaller support craft would be more concentrated in the 
coastal waters in the areas of naval installations, ports, and ranges. 
The number of activities that include the use of vessels for training 
events is lower (approximately 10 percent) than the number for testing 
activities. Testing can occur jointly with a training event, in which 
case that testing activity could be conducted from a training vessel.
    Additionally, a variety of smaller craft will be operated within 
the NWTT Study Area. Small craft types, sizes, and speeds vary. During 
training and testing, speeds generally range from 10-14 kn; however, 
vessels can and will, on occasion, operate within the entire spectrum 
of their specific operational capabilities. In all cases, the vessels/
craft will be operated in a safe manner consistent with the local 
conditions.

Standard Operating Procedures

    For training and testing to be effective, personnel must be able to 
safely use their sensors and weapon systems as they are intended to be 
used in military missions and combat operations and to their optimum 
capabilities. While standard operating procedures are designed for the 
safety of personnel and equipment and to ensure the success of training 
and testing activities, their implementation often yields benefits on 
environmental, socioeconomic, public health and safety, and cultural 
resources.
    Because standard operating procedures are essential to safety and 
mission success, the Navy considers them to be part of the planned 
specified activities, and they have been included in the environmental 
analysis in the 2020 NWTT FSEIS/OEIS. Additional details on standard 
operating procedures were provided in our Federal Register notice of 
proposed rulemaking (85 FR 33914; June 2, 2020); please see that notice 
of proposed rulemaking or the Navy's application for more information.

Comments and Responses

    We published the proposed rule in the Federal Register on June 2, 
2020 (85 FR 33914), with a 45-day comment period. With that proposed 
rule, we requested public input on our analyses, our preliminary 
findings, and the

[[Page 72324]]

proposed regulations, and requested that interested persons submit 
relevant information and comments. During the 45-day comment period, we 
received 9,047 comments. Of this total, one submission was from the 
Marine Mammal Commission, two submissions were from tribes or 
coalitions of tribes, three submissions were from state agencies or 
officials, and the remaining comments were from organizations or 
individuals acting in an official capacity (e.g., non-governmental 
organizations (NGOs)) and private citizens. We received some 
submissions that expressed general opposition toward the Navy's 
proposed training and testing activities and requested that NMFS not 
issue the regulations and LOAs, but provided no specific comments or 
information. These general comments have been noted, but because they 
did not include information pertinent to NMFS' decision, they are not 
addressed further.
    NMFS has reviewed and considered all public comments received on 
the proposed rule and issuance of the LOAs. General comments that did 
not provide information pertinent to NMFS' decisions have been noted, 
but are not addressed further. All substantive comments and our 
responses are described below. We provide no response to specific 
comments that addressed species or statutes not relevant to the 
rulemaking under section 101(a)(5)(A) of the MMPA (e.g., comments 
related to sea turtles). We organize our comment responses by major 
categories.

Impact Analysis and Thresholds

    Comment 1: A commenter stated that the criteria that the Navy has 
produced to estimate temporary and permanent threshold shift in marine 
mammals, and that NMFS applied in the proposed rule, are erroneous and 
non-conservative. According to the commenter, Wright (2015) has 
identified several statistical and numerical faults in the Navy's 
approach, such as pseudo-replication, use of means rather than onset 
(as with the treatment of blast trauma), and inconsistent treatment of 
data, that tend to bias the criteria towards an underestimation of 
effects. The commenter stated that similar and additional issues were 
raised by a dozen scientists during the public comment period on the 
draft criteria held by NMFS. The commenter asserts that the issue is 
NMFS' broad extrapolation from a small number of individual animals, 
mostly bottlenose dolphins, without taking account of what Racca et al. 
(2015b) have succinctly characterized as a ``non-linear accumulation of 
uncertainty.'' The commenter asserts that the auditory impact criteria 
should be revised. Another commenter noted that NMFS has not considered 
that repeated exposure to noise that can cause TTS can lead to PTS, or 
that TTS increases the likelihood of vessel strike.
    Response: The ``Navy criteria'' that the commenter references for 
estimating were developed in coordination with NMFS and ultimately 
finalized, following three peer reviews and three public comment 
periods, as NMFS' Technical Guidance for Assessing the Effects of 
Anthropogenic Sound on Marine Mammal Hearing-Underwater Acoustic 
Thresholds for Onset of Permanent and Temporary Threshold Shifts 
(Acoustic Technical Guidance). NMFS disagrees with the commenter's 
criticism about inconsistent treatment of data and any suggestion that 
the use of the Acoustic Technical Guidance provides erroneous results. 
The Acoustic Technical Guidance represents the best available science 
and provides thresholds and weighting functions that allow us to 
predict when marine mammals are likely to incur permanent threshold 
shift (PTS). All public comments on the Acoustic Technical Guidance, 
including those referenced by the commenter here, were addressed in 
full in the Federal Register notice announcing the finalization of the 
Acoustic Technical Guidance. We refer the reader to https://www.federalregister.gov/documents/2016/08/04/2016-18462/technical-guidance-for-assessing-the-effects-of-anthropogenic-sound-on-marine-mammal for full responses to those previously raised comments.
    As described in the Estimated Take of Marine Mammals section, when 
the acoustic thresholds, the Navy model, and other inputs into the take 
calculation are considered, the authorized incidental takes represent 
the maximum number of instances in which marine mammals are reasonably 
expected to be taken, which is appropriate under the statute and there 
is no need or requirement for NMFS to authorize a larger number.
    Multiple studies from humans, terrestrial mammals, and marine 
mammals have demonstrated less temporary threshold shift (TTS) from 
intermittent exposures compared to continuous exposures with the same 
total energy because hearing is known to experience some recovery in 
between noise exposures, which means that the effects of intermittent 
noise sources such as tactical sonars are likely overestimated. Marine 
mammal TTS data have also shown that, for two exposures with equal 
energy, the longer duration exposure tends to produce a larger amount 
of TTS. Most marine mammal TTS data have been obtained using exposure 
durations of tens of seconds up to an hour, much longer than the 
durations of many tactical sources (much less the continuous time that 
a marine mammal in the field would be exposed consecutively to those 
levels), further suggesting that the use of these TTS data are likely 
to overestimate the effects of sonars with shorter duration signals.
    Regarding the suggestion of pseudoreplication and erroneous models, 
since marine mammal hearing and noise-induced hearing loss data are 
limited, both in the number of species and in the number of individuals 
available, attempts to minimize pseudoreplication would further reduce 
these already limited data sets. Specifically, with marine mammal 
behaviorally derived temporary threshold shift studies, behaviorally 
derived data are only available for two mid-frequency cetacean species 
(bottlenose dolphin, beluga) and two phocid (in-water) pinniped species 
(harbor seal and northern elephant seal), with otariid (in-water) 
pinnipeds and high-frequency cetaceans only having behaviorally-derived 
data from one species each. Arguments from Wright (2015) regarding 
pseudoreplication within the TTS data are therefore largely irrelevant 
in a practical sense because there are so few data. Multiple data 
points were not included for the same individual at a single frequency. 
If multiple data existed at one frequency, the lowest TTS onset was 
always used. There is only a single frequency where TTS onset data 
exist for two individuals of the same species: 3 kHz for bottlenose 
dolphins. Their TTS (unweighted) onset values were 193 and 194 dB re 1 
[mu]Pa2s. Thus, NMFS believes that the current approach makes the best 
use of the given data. Appropriate means of reducing pseudoreplication 
may be considered in the future, if more data become available. Many 
other comments from Wright (2015) and the comments from Racca et al. 
(2015b) appear to be erroneously based on the idea that the shapes of 
the auditory weighting functions and TTS/PTS exposure thresholds are 
directly related to the audiograms; i.e., that changes to the composite 
audiograms would directly influence the TTS/PTS exposure functions 
(e.g., Wright (2015) describes weighting functions as ``effectively the 
mirror image of an audiogram'' (p. 2) and states, ``The underlying goal 
was to estimate how much a sound level needs to be above

[[Page 72325]]

hearing threshold to induce TTS.'' (p. 3)). Both statements are 
incorrect and suggest a fundamental misunderstanding of the criteria/
threshold derivation. This would require a constant (frequency-
independent) relationship between hearing threshold and TTS onset that 
is not reflected in the actual marine mammal TTS data. Attempts to 
create a ``cautionary'' outcome by artificially lowering the composite 
audiogram thresholds would not necessarily result in lower TTS/PTS 
exposure levels, since the exposure functions are to a large extent 
based on applying mathematical functions to fit the existing TTS data.
    Please refer to the response to Comment 9 for additional 
information regarding the use of ``means rather than onset'' in the 
analysis of blast trauma.
    Regarding the comment about repeated exposures to TTS leading to 
PTS, NMFS is aware of studies by Kujawa and Liberman (2009) and Lin et 
al. (2011), which found that despite completely reversible TS that 
leave cochlear sensory cells intact, large (but temporary) TS could 
cause synaptic level changes and delayed cochlear nerve degeneration in 
mice and guinea pigs. However, the large TS (i.e., maximum 40 decibel 
dB) that led to the synaptic changes shown in these studies are in the 
range of the large shifts used by Southall et al. (2007) and in NMFS 
Acoustic Technical Guidance (2018) to define PTS onset (i.e., 40 dB). 
There is no evidence indicating that smaller levels of TTS would lead 
to similar changes or the long-term implications of irreversible neural 
degeneration and NMFS has included several conservative assumptions in 
its protocol for examining marine mammal hearing loss data (e.g., using 
a 6 dB threshold shift to represent TTS onset, not directly accounting 
for exposures that did not result in threshold shifts, assuming there 
is no recovery with the 24-h baseline accumulation period or between 
intermittent exposures). Moreover, as described in the final rule, TTS 
incurred as a result of exposures to Navy NWTT activities is expected 
to be of a smaller degree and, further, no individual is expected to 
incur repeated exposures of TTS in a manner that could accrue to PTS. 
Nonetheless, NMFS acknowledges the complexity of sound exposure on the 
nervous system, and will re-examine this issue as more data become 
available. Separately, the commenter provides no credible evidence to 
support the speculative assertion that TTS increases the likelihood of 
vessel strike of marine mammals.
    Comment 2: A commenter recommended that NMFS clarify whether and 
how the Navy incorporated uncertainty in its density estimates for its 
animat modeling specific to NWTT and if uncertainty was not 
incorporated, re-estimate the numbers of marine mammal takes based on 
the uncertainty inherent in the density estimates provided in 
Department of the Navy (2019) or the underlying references (Jefferson 
et al., 2017, Smultea et al., 2017, NMFS SARs, etc.).
    Response: Uncertainty was incorporated into the density estimates 
used for modeling and estimating take for NMFS' rule. Where available, 
a coefficient of variation (CV) was used to represent uncertainty in 
the species-specific density estimates. The CV was incorporated into 
the acoustic effects model by randomly varying the number of animats 
distributed for each scenario within the range described by the CV. If 
a measure of uncertainty was not available, then the number of animats 
distributed in the model remained the same for each modeled scenario. 
Multiple iterations of each modeled scenario were run until the results 
converged with minimal variation, meaning that even without 
incorporating a CV into the animat distribution, uncertainty in the 
exposure results were minimized.
    The commenter is referred to the technical report titled 
Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods 
and Analytical Approach for Phase III Training and Testing (U.S. 
Department of the Navy, 2018) for clarification on the consideration of 
uncertainty in density estimates. Specifically, see Section 4.2 (Marine 
Species Distribution Builder) of the technical report where details are 
provided on how statistical uncertainty surrounding density estimates 
was incorporated into the modeling for the NWTT Study Area, as has been 
done for all other recent NMFS and Navy analyses of training and 
testing at sea. To the commenter's more specific question, as with the 
2018/2020 Hawaii-Southern California Training and Testing (HSTT) final 
rules and 2020 Mariana Islands Training and Testing (MITT) final rule, 
a lognormal distribution was used in the density regression model. 
Uncertainty was incorporated into the take estimation through the 
density estimates and it is not necessary to re-estimate the take 
numbers for marine mammals.
    Comment 3: A commenter recommended that NMFS specify in the 
preamble to the final rule whether the data regarding behavioral 
audiograms (Branstetter et al., 2017, Kastelein et al., 2017b) and TTS 
(Kastelein et al., 2017a and c, Popov et al., 2017, Kastelein et al., 
2018a and 2019b, c, and d) support the continued use of the current 
weighting functions and PTS and TTS thresholds.
    Response: NMFS has carefully considered the references that the 
commenter cites and the new data included in those articles are 
consistent with the thresholds and weighting functions included in the 
current version of the Acoustic Technical Guidance (NMFS, 2018). 
Furthermore, the recent peer-reviewed updated marine mammal noise 
exposure criteria by Southall et al. (2019a) provide identical PTS and 
TTS thresholds and weighting functions to those provided in NMFS' 
Acoustic Technical Guidance. NMFS will continue to review and evaluate 
new relevant data as it becomes available and consider the impacts of 
those studies on the Acoustic Technical Guidance to determine what 
revisions/updates may be appropriate.
    Comment 4: A commenter stated that the Navy, and in turn NMFS, has 
not provided adequate justification for ignoring the possibility that 
single underwater detonations can cause a behavioral response. The 
commenter recommends that NMFS estimate and ultimately authorize 
behavior takes of marine mammals during all explosive activities, 
including those that involve single detonations. In a similar comment, 
another commenter stated that the literature on responses to explosions 
does not distinguish between single and multiple detonations, and 
asserts that it is arbitrary for NMFS, in estimating takes and 
assessing impacts, to assume that only multiple rounds of in-water 
detonations can cause Level B harassment takes by behavioral 
disturbance.
    Response: NMFS does not ignore the possibility that single 
underwater detonations can cause a behavioral response. The current 
take estimate framework allows for the consideration of animals 
exhibiting behavioral disturbance during single explosions as they are 
counted as ``taken by Level B harassment'' if they are exposed above 
the TTS threshold, which is only 5 dB higher than the behavioral 
harassment threshold. We acknowledge in our analysis that individuals 
exposed above the TTS threshold may also be harassed by behavioral 
disruption and those potential impacts are considered in the negligible 
impact determination. Neither NMFS nor the Navy are aware of evidence 
to support the assertion that animals will have significant behavioral 
responses (i.e., those that would rise to the level of a take) to 
temporally and

[[Page 72326]]

spatially isolated explosions at received levels below the TTS 
threshold. However, if any such responses were to occur, they would be 
expected to be few and to result from exposure to the somewhat higher 
received levels bounded by the TTS thresholds and would, thereby, be 
accounted for in the take estimates. The derivation of the explosive 
injury criteria is provided in the 2017 technical report titled 
Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects 
Analysis (Phase III).
    Comment 5: A commenter stated that the behavioral response 
functions (BRFs) rely on captive animal studies and the risk functions 
do not incorporate a number of relevant studies on wild marine mammals 
(specifically referencing a passive acoustic study on blue whales). The 
commenter states that some were included in the only published 
quantitative synthesis of behavioral response data, Gomez et al. 
(2016), while others appeared after that synthesis was published, and 
after the Navy produced its BRFs two years ago. The commenter asserts 
that exclusion of those studies fails to meet regulatory requirements 
(citing to National Environmental Policy Act (NEPA) regulations) that 
base evaluation of impacts on research methods generally accepted in 
the scientific community and that the result is arbitrary.
    The commenter asserts that it is not clear from the proposed rule, 
the 2020 NWTT DSEIS/OEIS, or the Navy's associated technical report on 
acoustic ``criteria and thresholds'' exactly how each of the studies 
considered relevant were applied in the analysis, or how the functions 
were fitted to the data, but the available evidence on behavioral 
response raises concerns that--notwithstanding the agencies' claims to 
the contrary--the functions are not conservative for some species. For 
this reason and others, the commenter requests that NMFS make 
additional technical information available, including expert 
elicitation and peer review (if any), so that the public can fully 
comment pursuant to the Administrative Procedure Act (APA).
    Response: We refer the commenter to the Criteria and Thresholds for 
the U.S. Navy Acoustic and Explosive Effects Analysis (Phase III) 
Technical Report (U.S. Department of the Navy, 2017) for details on how 
the Navy accounted for the differences in captive and wild animals in 
the development of the behavioral response risk functions, which NMFS 
has evaluated and deemed appropriate to incorporate into the analysis 
in the rule. The appendices to this report detail the specific data 
points used to generate the BRFs. Data points come from published data 
that is readily available and cited within the technical report.
    The Navy used the best available science in the analysis, which has 
been reviewed by external scientists and approved by NMFS. The Navy 
considered all data available at the time for the development of 
updated criteria and thresholds, and limiting the data to the small 
number of field studies would not provide enough data with which to 
develop the new risk functions. In addition, the Navy accounted for the 
fact that captive animals may be less sensitive, and the scale at which 
a moderate-to-severe response was considered to have occurred is 
different for captive animals than for wild animals, as the Navy 
understands those responses will be different. The new risk functions 
were developed in 2016, before several recent papers were published or 
the data were available. The Navy and NMFS continue to evaluate the 
information as new science is made available. The criteria have been 
rigorously vetted within the Navy community, among scientists during 
expert elicitation, and then reviewed by the public before being 
applied. It is unreasonable to revise and update the criteria and risk 
functions every time a new paper is published. NMFS concurs with the 
Navy's evaluation and conclusion that there is no new information that 
necessitates changing the acoustic thresholds at this time.
    These new papers provide additional information, and the Navy is 
considering them for updates to the criteria in the future, when the 
next round of updated criteria will be developed. Regarding 
consideration of research findings involving a passive acoustic study 
on blue whale vocalizations and behavior, the Navy considered multiple 
recent references, including but not limited to: Paniagua-Mendoza, 
2017; Lesage, 2017; DeRuiter, 2017; Mate, 2016; Lomac-MacNair, 2016; 
Friedlaender, 2016; and Mate, 2015. Thus far, no new information has 
been published or otherwise conveyed that would fundamentally change 
the assessment of impacts or conclusions of this rule. To be included 
in the BRF, data sets needed to relate known or estimable received 
levels to observations of individual or group behavior. Melcon et al. 
(2012) does not relate observations of individual/group behavior to 
known or estimable received levels at that individual/group. In Melcon 
et al. (2012), received levels at the HARP buoy averaged over many 
hours are related to probabilities of D-calls, but the received level 
at the blue whale individuals/group are unknown.
    Comment 6: Commenters recommended that NMFS refrain from using cut-
off distances in conjunction with the Bayesian BRFs and re-estimate the 
numbers of marine mammal takes based solely on the Bayesian BRFs, as 
the use of cut-off distances could be perceived as an attempt to reduce 
the numbers of takes. One commenter suggested that the actual cut-off 
distances used by the Navy appear to be unsubstantiated and questioned 
several of the choices made in the development of the cutoff distances 
(although alternate recommendations were not included).
    Response: The consideration of proximity (cut-off distances) was 
part of the criteria developed in consultation between the Navy and 
NMFS, and is appropriate based on the best available science which 
shows that marine mammal responses to sound vary based on both sound 
level and distance. Therefore these cut-off distances were applied 
within the Navy's acoustic effects model. The derivation of the BRFs 
and associated cut-off distances is provided in the 2017 technical 
report titled Criteria and Thresholds for U.S. Navy Acoustic and 
Explosive Effects Analysis (Phase III). To account for non-applicable 
contextual factors, all available data on marine mammal reactions to 
actual Navy activities and other sound sources (or other large scale 
activities such as seismic surveys when information on proximity to 
sonar sources was not available for a given species group) were 
reviewed to find the farthest distance to which significant behavioral 
reactions were observed. For use as distance cut-offs to be used in 
conjunction with the BRFs, these distances were rounded up to the 
nearest 5 or 10 km interval, and for moderate to large scale activities 
using multiple or louder sonar sources, these distances were greatly 
increased--doubled in most cases. The Navy's BRFs applied within these 
distances provide technically sound methods reflective of the best 
available science to estimate the impact and potential take for the 
actions analyzed within the 2020 NWTT FSEIS/OEIS and included in this 
rule. NMFS has independently assessed the thresholds used by the Navy 
to identify Level B harassment by behavioral disturbance (referred to 
as ``behavioral harassment thresholds'' throughout the rest of the 
rule) and finds that they appropriately apply the best available 
science and it is not necessary to recalculate take estimates.
    The commenters also specifically expressed concern that distance 
``cut-

[[Page 72327]]

offs'' alleviate some of the exposures that would otherwise have been 
counted if the received level alone were considered. It is unclear why 
the commenters find this inherently inappropriate, as this is what the 
data show. There are multiple studies illustrating that in situations 
where one would expect behavioral disturbance of a certain degree 
because of the received levels at which previous responses were 
observed, it has not occurred when the distance from the source was 
larger than the distance of the first observed response.
    Comment 7: A commenter stated that dipping sonar, like hull-mounted 
sonar, appears to be a significant predictor of deep-dive rates in 
beaked whales, with the dive rate falling significantly (e.g., to 35 
percent of that individual's control rate) during sonar exposure, and 
likewise appears associated with habitat abandonment. According to the 
commenter, the data sources used to produce the Navy's BRFs concern 
hull-mounted sonar, an R/V-deployed sonar playback, or an in-pool 
source. According to the commenter, the generic BRF for beaked whales 
used in the rule does not incorporate their heightened response to 
these sources, although such a response would be presumed to shift its 
risk function ``leftward.'' Nor do the response functions for other 
species account for this difference, although unpredictability is known 
to exacerbate stress response in a diversity of mammalian species and 
should conservatively be assumed, in this case, to lead to a heightened 
response in marine mammal species other than beaked whales.
    Response: The best available science was used to develop the BRFs. 
The current beaked whale BRF acknowledges and incorporates the 
increased sensitivity observed in beaked whales during both behavioral 
response studies and during actual Navy training events, as well as the 
fact that dipping sonar can have greater effects than some other 
sources with the same source level. Specifically, the distance cut-off 
for beaked whales is 50 km, larger than any other group. Moreover, 
although dipping sonar has a significantly lower source level than 
hull-mounted sonar, it is included in the category of sources with 
larger distance cut-offs, specifically in acknowledgement of its 
unpredictability and association with observed effects. This means that 
``takes'' are reflected at lower received levels that would have been 
excluded because of the distance for other source types. An article 
referenced by the commenter (Associating patterns in movement and 
diving behavior with sonar use during military training exercises: A 
case study using satellite tag data from Cuvier's beaked whales at the 
Southern California Anti-submarine Warfare Range (Falcone et al., 
2017)) was not available at the time the BRFs were developed. However, 
NMFS and the Navy have reviewed the article and concur that neither 
this article nor any other new information that has been published or 
otherwise conveyed since the BRFs were developed changes the assessment 
of impacts or conclusions in the 2020 NWTT FSEIS/OEIS or in this 
rulemaking. Additionally, the current beaked whale BRF covers the 
responses observed in this study since the beaked whale risk function 
is more sensitive than the other risk functions at lower received 
levels. The researchers involved with the study continue to further 
refine their analytical approach and integrate additional statistical 
parameters for future reporting. Nonetheless, the new information and 
data presented in the article were thoroughly reviewed by NMFS and the 
Navy and will be quantitatively incorporated into future BRFs, as 
appropriate, when and if other new data that would meaningfully change 
the functions would necessitate their revision. Furthermore, ongoing 
beaked whale monitoring at the same site where the dipping sonar tests 
were conducted has not documented habitat abandonment by beaked whales. 
Passive acoustic detections of beaked whales have not significantly 
changed over ten years of monitoring (DiMarzio et al., 2018, updated in 
2020). From visual surveys in the same area since 2006, there have been 
repeated sightings of the same individual beaked whales, beaked whale 
mother-calf pairs, and beaked whale mother-calf pairs with mothers on 
their second calf (Schorr et al., 2018, 2020). Satellite tracking 
studies of beaked whales documented high site fidelity to this area 
(Schorr et al., 2018, updated in 2020).
    Comment 8: A commenter recommends that NMFS: (1) Explain why, if 
the constants and exponents for onset mortality and onset slight lung 
injury thresholds for the current phase of incidental take rulemaking 
for the Navy (Phase III) have been amended to account for lung 
compression with depth, they result in lower rather than higher 
absolute thresholds when animals occur at depths greater than 8 m and 
(2) specify what additional assumptions were made to explain this 
counterintuitive result.
    Response: The derivation of the explosive injury equations, 
including any assumptions, is provided in the 2017 technical report 
titled Criteria and Thresholds for U.S. Navy Acoustic and Explosive 
Effects Analysis (Phase III). Specifically, the equations were modified 
for the current rulemaking period (Phase III) to fully incorporate the 
injury model in Goertner (1982), specifically to include lung 
compression with depth. NMFS independently reviewed and concurred with 
this approach.
    The impulse mortality/injury equations are depth dependent, with 
thresholds increasing with depth due to increasing hydrostatic pressure 
in the model for both the previous 2015-2020 phase of rulemaking (Phase 
II) and Phase III. The underlying experimental data used in Phase II 
and Phase III remain the same, and two aspects of the Phase III 
revisions explain the relationships the commenter Notes:
    (1) The numeric coefficients in the equations are computed by 
inserting the Richmond et al. (1973) experimental data into the model 
equations. Because the Phase III model equation accounts for lung 
compression, the plugging of experimental exposure values into a 
different model results in different coefficients. The numeric 
coefficients are slightly larger in Phase III versus Phase II, 
resulting in a slightly greater threshold near the surface.
    (2) The rate of increase for the Phase II thresholds with depth is 
greater than the rate of increase for Phase III thresholds with depth 
because the Phase III equations take into account the corresponding 
reduction in lung size with depth (making an animal more vulnerable to 
injury per the Goertner model), as the commenter notes.
    Comment 9: A commenter recommended that NMFS use onset mortality, 
onset slight lung injury, and onset gastrointestinal (GI) tract injury 
thresholds rather than the 50-percent thresholds to estimate both the 
numbers of marine mammal takes and the respective ranges to effect. If 
NMFS does not implement the recommendation, the commenter further 
recommends that NMFS (1) specify why it is inconsistently basing its 
explosive thresholds for Level A harassment on onset of PTS and Level B 
harassment on onset of TTS and onset behavioral response, while the 
explosive thresholds for mortality and Level A harassment are based on 
the 50-percent criteria for mortality, slight lung injury, and GI tract 
injury, (2) provide scientific justification supporting the assumption 
that slight lung and GI tract injuries are less severe than PTS and 
thus the 50-percent rather than onset criteria are more appropriate for 
estimating Level A harassment for those types of injuries,

[[Page 72328]]

and (3) justify why the number of estimated mortalities should be 
predicated on at least 50 percent rather than 1 percent of the animals 
dying.
    Another commenter also stated that they do not understand why the 
Navy and NMFS use the 50 percent average for the explosive impact 
analysis while using onset for purposes of assessing the effectiveness 
of the Navy's mitigation zones. This commenter also stated that this 
approach is not consistent with the probability standards set forth in 
the MMPA. The MMPA incorporates a standard of ``significant potential'' 
into its definition of ``injury'' for military readiness activities; 
this standard plainly differs from the higher ``likelihood'' standard 
that applies to behavioral disruption. And while the probability 
standard for mortality is not specifically defined in the Act, Congress 
expressly amended the MMPA in 1994 to incorporate a ``potential'' 
standard in the wake of the Ninth Circuit decision in U.S. v. Hiyashi, 
22 F.3d 859 (9th Cir. 1993). If NMFS is to satisfy the plain language 
of the MMPA, and provide a more conservative estimate of harm, it 
cannot base its mortality and injury estimates on the mean.
    Response: First, we note an error in one of the commenters' 
assertions. The BRFs used in the behavioral harassment thresholds are 
not based on the onset of any behavioral response. They are based on 
responses at or above a severity at which we believe ``take'' occurs, 
therefore the BRFs do not predict onset behavioral response. Also, the 
``onset'' of TTS is not when there is any measurable TTS (i.e., 0.5, 1 
dB); we've defined the onset of TTS as where there is a consistently 
measurable amount of TTS, which has been defined as 6 dB of TTS. 
Additionally, the weighting function components of the TTS thresholds 
are based on the average of all of the data points. Since the PTS 
threshold is derived from an offset of the TTS threshold, this same 
averaging concept holds true for PTS criteria.
    For explosives, the type of data available are different than those 
available for hearing impairment, and this difference supports the use 
of different prediction methods. Nonetheless, as appropriate and 
similar to take estimation methods for PTS, NMFS and the Navy have used 
a combination of exposure thresholds and consideration of mitigation to 
inform the take estimates. The Navy used the range to 1 percent risk of 
onset mortality and onset injury (also referred to as ``onset'' in the 
2020 NWTT FSEIS/OEIS) to inform the development of mitigation zones for 
explosives. Ranges to effect based on 1 percent risk criteria to onset 
injury and onset mortality were examined to ensure that explosive 
mitigation zones would encompass the range to any potential mortality 
or non-auditory injury, affording actual protection against these 
effects. In all cases, the mitigation zones for explosives extend 
beyond the range to 1 percent risk of onset non-auditory injury, even 
for a small animal (representative mass = 5 kg). Given the 
implementation and expected effectiveness of this mitigation, the 
application of the indicated threshold is appropriate for the purposes 
of estimating take. Using the 1 percent onset non-auditory injury risk 
criteria to estimate take would result in an over-estimate of take, and 
would not afford extra protection to any animal. Specifically, 
calculating take based on marine mammal density within the area that an 
animal might be exposed above the 1 percent risk to onset injury and 
onset mortality criteria would over-predict effects because many of 
those exposures will not happen because of the effective mitigation. 
The Navy, in coordination with NMFS, has determined that the 50 percent 
incidence of onset injury and onset mortality occurrence is a 
reasonable representation of a potential effect and appropriate for 
take estimation, given the mitigation requirements at the 1 percent 
onset injury and onset mortality threshold, and the area ensonified 
above this threshold would capture the appropriate reduced number of 
likely injuries.
    While the approaches for evaluating non-auditory injury and 
mortality are based on different types of data and analyses than the 
evaluation of PTS and behavioral disturbance, and are not identical, 
NMFS disagrees with the commenter's assertion that the approaches are 
inconsistent, as both approaches consider a combination of thresholds 
and mitigation (where applicable) to inform take estimates. For the 
same reasons, it is not necessary for NMFS to ``provide scientific 
justification supporting the assumption that slight lung and GI tract 
injuries are less severe than PTS,'' as that assumption is not part of 
NMFS' rationale for the methods used. NMFS has explained in detail its 
justification for the number of estimated mortalities, which is based 
on both the 50 percent threshold and the mitigation applied at the one 
percent threshold. Further, we note that many years of Navy monitoring 
following explosive exercises has not detected evidence that any injury 
or mortality has resulted from Navy explosive exercises with the 
exception of one incident with dolphins in California, after which 
mitigation was adjusted to better account for explosives with delayed 
detonations (i.e., zones for events with time-delayed firing were 
enlarged).
    Further, for these reasons, the methods used for estimating 
mortality and non-auditory injury are appropriate for estimating take, 
including determining the ``significant potential'' for non-auditory 
injury consistent with the statutory definition of Level A harassment 
for military readiness activities, within the limits of the best 
available science. Using the one percent threshold would be 
inappropriate and result in an overestimation of effects, whereas given 
the mitigation applied within this larger area, the 50 percent 
threshold results an appropriate mechanism for estimating the 
significant potential for non-auditory injury.
    Comment 10: A commenter had concerns regarding the various areas, 
abundance estimates, and correction factors that the Navy used for 
pinnipeds. The commenter referenced information in the context of both 
what the Navy used and what the commenter argued they should have used 
and summarized the discussion with several recommendations.
    Broadly, the commenter stated that since NMFS used the draft 2019 
Stock Assessment Reports (SARs) or the most recently finalized SAR for 
the abundance estimates in its negligible impact determination analyses 
(Tables 9 and 52-57 in the Federal Register notice), it also must use 
the most recent abundance estimates to inform the associated densities 
and resulting take estimates as those abundance estimates represent the 
best available science.
    The commenter noted that the abundance estimate for northern fur 
seals was based on pup count data from 2014 and did not include the 
more recent data from Bogoslof Island in 2015 and from St. Paul and St. 
George in 2016. For northern fur seals, the commenter recommended that 
NMFS revise the density based on the abundance estimate that includes 
data from Bogoslof Island in 2015 and from St. Paul and St. George in 
2016.
    The commenter noted that the abundance estimate for Guadalupe fur 
seals was based on pup count data from 2008 and 2010 and did not 
include the more recent survey data from 2013-2015 and associated 
correction factors. For Guadalupe fur seals, the commenter recommended 
that NMFS revise the density based on abundance data from 2013-2015 at 
both Isla Guadalupe and Isla San Benito.

[[Page 72329]]

    The commenter stated that the abundance estimate for Steller sea 
lions was based on pup and non-pup count and trend data from 2015 and 
did not incorporate the more recent trend data from 2017. The commenter 
also noted that the Navy applied non-pup growth rates to the non-pup 
and pup abundance estimates rather than applying the non-pup growth 
rates to the non-pup abundances and the pup growth rates to the pup 
abundances. For Steller sea lions, the commenter recommended that NMFS 
revise the density based on adjusting the 2015 pup and non-pup data 
using the trend data from 2017, applying the non-pup growth rate to the 
non-pup counts and the pup growth rates to the pup counts.
    For Guadalupe fur seal, Steller sea lion, California sea lions, 
harbor seals, and elephant seals, the commenter recommended that NMFS 
revise the densities based on applying the relevant growth rates up to 
at least 2020.
    For harbor seals in the Strait of Juan de Fuca and the San Juan 
Islands, the commenter recommended that NMFS revise the densities based 
on assuming that 46 percent of the animals would be in the water at a 
given time from Huber et al. (2001).
    Based on the recommendations above, the commenter recommended that 
NMFS re-estimate the numbers of takes accordingly in the final rule.
    Response: The Navy provided NMFS clarification regarding the 
referenced concerns about areas, abundance estimates, and correction 
factors that were used for pinnipeds. We first note that take 
estimation is not an exact science. There are many inputs that go into 
an estimate of marine mammal exposure, and the data upon which those 
inputs are based come with varying levels of uncertainty and precision. 
Also, differences in life histories, behaviors, and distributions of 
stocks can support different decisions regarding methods in different 
situations. Further, there may be more than one acceptable method to 
estimate take in a particular situation. Accordingly, while the 
applicant bears the responsibility of providing by species or stock the 
estimated number and type of takes (see 50 CFR 216.104(a)(6)) and NMFS 
always ensures that an applicant's methods are technically supportable 
and reflect the best available science, NMFS does not prescribe any one 
method for estimating take (or calculating some of the specific take 
estimate components that the commenter is concerned about). NMFS 
reviewed the areas, abundances, and correction factors used by the Navy 
to estimate take and concurs that they are appropriate. While some of 
the suggestions the commenter makes could provide alternate valid ways 
to conduct the analyses, these modifications are not required in order 
to have equally valid and supportable analyses. In addition, we note 
that (1) some of the specific recommendations that the commenter makes 
are largely minor in nature within the context of our analysis (e.g., 
``46 not 37 percent'') and (2) even where the recommendation is 
somewhat larger in scale, given the ranges of the majority of these 
stocks, the size of the stocks, and the number and nature of pinniped 
takes, recalculating the estimated take for any of these pinniped 
stocks using the commenter's recommended changes would not change NMFS' 
assessment of impacts on the rates of recruitment or survival of any of 
these stocks, or the negligible impact determinations. Below, we 
address the commenter's issues in more detail and, while we do not 
explicitly note it in every section, NMFS has reviewed the Navy's 
analysis and choices in relation to these comments and concurs that 
they are technically sound and reflect the best available science.
    Northern fur seal--The Navy analyzed unpublished tagging data 
provided by subject matter experts at NMFS' Alaska Fisheries Science 
Center (AKFSC). The Navy also did not integrate the 2015 data from 
Bogoslof Island suggested by the commenter based on advice from subject 
matter experts at the AKFSC, due to a volcanic eruption at the rookery 
on Bogoslof Island where a portion of the counts are made, which in the 
opinion of the AKFSC experts skewed the 2015 data. Therefore, the Navy 
found that incorporating this data would not reflect the best available 
science. NMFS concurs with this assessment, and therefore, has not 
included this information in the take estimation in this final rule. 
Regarding the recommendation for NMFS to revise the density based on 
the abundance estimate from St. Paul and St. George in 2016, to 
complete the modeling on schedule, the density data available at that 
time from the final 2016 SAR (Muto et al., 2017) were used. Note that 
the latest pup counts reported in the final 2019 SAR (Muto et al., 
2020) using the more recent data from Bogoslof Island in 2015 and St. 
Paul and St. George in 2016 result in a lower pup count than the one 
used in the density calculation, which suggests that the estimates used 
for this final rule are likely conservative.
    Guadalupe fur seal--The Navy Marine Species Density Database 
(NMSDD) technical report describes density estimates that were used in 
the Navy's acoustics effects model. To complete the modeling on 
schedule, the density data available at that time from the final 2016 
SAR (Carretta et al., 2017) were used. The initial abundance estimate 
of 20,000 fur seals was based on surveys between 2008 and 2010 as the 
commenter points out, but to account for a likely increasing population 
trend, the Navy applied a growth rate of 7.64 percent per year to 
estimate an abundance for the year 2017. That resulted in an abundance 
of 33,485 fur seals (a 67 percent increase over the reported abundance 
of 20,000). The final 2019 SAR (Carretta et al., 2020) reported 
comparable abundance estimates based on the later surveys, some of 
which were from sources published in 2018, and an estimated growth rate 
of 5.9 percent, less than the growth rate applied by the Navy. The 
Navy's abundance estimate for the year 2017 is consistent with the 
latest abundance estimates.
    Steller sea lion--As stated above, the NMSDD technical report 
describes density estimates that were used in the Navy's acoustics 
effects model. To complete the modeling on schedule, the density data 
available at that time from the final 2016 SAR (Muto et al., 2017) were 
used. Steller sea lion densities were calculated independently for 
regional populations in Washington, Oregon, California, and southeast 
Alaska, consistent with the stock assessment reports. No trend data 
were (or are currently) estimated for pups in Washington, therefore, 
the non-pup growth rate of 8.77 percent per year was used for the 
entire population. In addition, the baseline abundance for Washington 
sea lions was increased over the abundance from the stock assessment 
report based on data reported in Wiles (2015) before the growth rate 
was applied to project a 2017 abundance. For sea lions in Oregon, 
California, and southeast Alaska the non-pup growth rate was used, 
because the number of non-pups in each population was substantially 
greater than the number of pups. Using separate growth rates for pups 
and non-pups in all three regions results in less than a 1 percent 
increase in the projected 2017 abundance. The associated change in the 
density is minimal and would not change the results of NMFS' or the 
Navy's analysis of acoustic impacts on Steller sea lions.
    Harbor seal--Density estimates for harbor seal in the Strait of 
Juan de Fuca and San Juan Islands were based on sighting data provided 
by the Washington Department of Fish and Game (Jeffries, 2017). In the 
context of analyzing that data, a 37 percent in-

[[Page 72330]]

water correction factor was applied to the abundance estimate, which is 
specific to southern Puget Sound. Huber et al. (2001) noted that a 46 
percent in-water correction factor would have been more appropriate 
given that the survey location was in the Strait. However, there were 
specific haulout factors for other areas within the Study Area that 
gave lower estimates throughout the Inland Waters. Subject matter 
experts from the Alaska Fisheries Science Center and the Northwest 
Fisheries Science Center concurred with the Navy's use of 37 percent as 
being most representative.
    Regarding revising the densities based on applying the relevant 
growth rates up to at least 2020, the density estimates are based on 
sighting numbers from surveys over many years to encompass variation 
and are not future predictions. It would not be appropriate to base 
densities on growth rates. The densities do not incorporate abundances 
or estimates of growth rate since the abundances for population and 
their population trend (reduction or growth) are not directly 
applicable to the density within a given area. Subject matter experts 
at the NMFS Alaska Fisheries Science Center advised in 2015 and again 
in 2019 that growth/decline rates provided in the SARs should not be 
used to project future population numbers for use in the Navy's 
analysis where abundance have been integrated into the analysis. NMFS 
concurs with this assessment and has not applied the growth rates in 
the take estimation in this final rule.
    Additionally, the Navy's purpose in applying an annual growth rate 
to estimate pinniped abundances in 2017 was to account for stock 
assessment report abundances that were based on surveys conducted 
several years prior to 2017. The intent was to update an older 
abundance estimate to the time of the Navy's analysis, not to predict 
abundances several years into the future. Projecting abundances from 
the past to the present (2017) allowed adjustments. For example, the 
growth rate for Guadalupe fur seal reported in the 2016 SAR (Carretta 
et al., 2017) was 10.3 percent; however, as the commenter pointed out, 
that rate is based on survey data from 2008-2010. Subsequently, the 
2015-2016 unusual mortality event (UME) occurred and the growth rate 
needed to be revised, which the Navy did. Projections extending into 
the future would not have allowed these types of corrections.
    Please see Comment 18 for additional information about the harbor 
seal abundance estimates included in this final rule.
    Comment 11: A commenter stated that a majority of the data that the 
Navy reviews and uses to determine species population density and 
breeding grounds is admittedly old and is not the most accurate 
representation of the species population or their geographic location. 
In its requirements for an authorization, the MMPA clearly states that 
requesters must include ``the species and numbers of marine mammals 
likely to be found within the activity area'' in order to demonstrate 
the requesting party's understanding of their activity impact on the 
animals and habitat. Normally, this sort of data requires up-to-date 
assessment reports, statistics, and accurate data that accurately 
portray the information that is necessary to require an authorization 
under the MMPA. However, the commenter stated that the Navy is 
violating the MMPA by providing outdated data from 2012 and 2014 to 
account for current patterns of marine activities in 2020-2027, even 
though they are conducting training exercises in the same Northwest 
waters where they are hoping to continue practicing for another seven 
years.
    The commenter suggested that the Navy should instead provide 
accurate up-to-date surveys of the activity areas as well as data for a 
long-term projection for at least 30 years of activity in the area if 
it continues to expect to apply for the same authorization over and 
over again.
    Response: The U.S. Navy Marine Species Density Database Phase III 
for the Northwest Training and Testing Study Area Final Technical 
Report includes an in-depth description of the process used to derive 
density estimates for marine mammal species occurring in the NWTT Study 
Area, and to provide a summary of species-specific and area-specific 
density estimates incorporated into the Marine Species Density 
Database. NMFS concurs that as described in the report, the process the 
Navy uses ensures that the density estimates reflect the best available 
data. Given the extensive and comprehensive process, it is not possible 
(or necessary) to update the density estimates or information about 
marine mammal breeding grounds each time a new paper is published, nor 
does the commenter provide additional data or publications that should 
have been incorporated into the density estimates or identify new 
information related to breeding grounds. However, the Navy will 
continue to incorporate, and NMFS will continue to consider, additional 
data for the next phase of Navy training and testing activities (Phase 
IV). Through the use of the Navy's methodology and the data inputs 
used, which were coordinated with NMFS, NMFS has ensured that this 
final rule incorporates the best available information related to 
marine mammal density and breeding areas in this final rule.
    The commenter suggested that the Navy should provide accurate, up-
to-date surveys of the activity areas, as well as data for a long-term 
projection for at least 30 years of activity in the NWTT Study Area. As 
discussed in the Monitoring section of this final rule, the Navy funds 
numerous marine mammal monitoring efforts, and this data is 
incorporated into the density and abundance estimates as appropriate. 
For example, this final rule incorporates new data regarding harbor 
seal abundance in NWTT inland waters from Navy-funded surveys (see the 
Analysis and Negligible Impact Determination section of this final 
rule). It is unclear what the commenter means by suggesting that the 
Navy provide a long-term projection for at least 30 years of activity 
in the area; however, NMFS notes that the current authorization is 
limited to seven years. NMFS will conduct a new analysis on the 
potential effects to marine mammals assuming the Navy seeks an 
authorization for training and testing activities beyond 2027 in the 
NWTT Study Area, and will ensure that the best available science, 
including new data as available, is included in that analysis.
    Comment 12: A commenter recommended that NMFS require the Navy to 
provide the method(s) by which species-specific cetacean densities were 
calculated for Western Behm Canal and cite the primary literature from 
which those data originated in the report (Department of the Navy 
(2019)). The commenter states that that level of information should be 
provided in all technical reports that underpin the Navy's density 
databases for future Phase III and IV DSEISs, DEISs, and proposed 
rules.
    Response: There were two primary sources of density data used to 
establish cetacean density estimates for Behm Canal: (1) The marine 
mammal occurrence/density report prepared in support of Navy activities 
at the Southeast Alaska Acoustic Measurement Facility (U.S. Department 
of the Navy, 2010) and (2) Density estimates derived by the National 
Marine Mammal Laboratory, Alaska Fisheries Science Center based on 
systematic surveys conducted in Southeast Alaska (e.g., Dahlheim et 
al., 2015). These sources were cited as appropriate in the species-
specific sections of Department of the Navy (2020); methods by which 
species-

[[Page 72331]]

specific density estimates were calculated are also described in 
Department of the Navy (2020). Multiple sources were used to establish 
pinniped density estimates for Behm Canal. All are cited as appropriate 
and methods described within the species-specific sections of 
Department of the Navy, 2020 (U.S. Navy Marine Species Density Database 
Phase III for the Northwest Training and Testing Study Area: Technical 
report. Naval Facilities Engineering Command Pacific, Pearl Harbor, 
Hawaii. 258 pages).
    Comment 13: A commenter stated that the delineation of Biologically 
Important Areas by NMFS, the updates made by the Navy to its predictive 
habitat models, and evidence of additional important habitat areas 
within the NWTT Study Area provide the opportunity for the agencies to 
improve upon their current approach to the development of alternatives 
by improving resolution of their analysis of operations.
    The commenter stated that recognizing that important habitat areas 
imply the non-random distribution and density of marine mammals in 
space and time, both the spatial location and the timing of training 
and testing events in relation to those areas is a significant 
determining factor in the assessment of acoustic impacts. Levels of 
acoustic impact are likely to be under- or over-estimated depending on 
whether the location of the modeled event is further from the important 
habitat area, or closer to it, than the actual event. Thus, there is a 
need for the Navy to compile and provide more information regarding the 
number, nature, and timing of testing and training events that take 
place within, or in close proximity to, important habitat areas, and to 
refine its scale of analysis of operations to match the scale of the 
habitat areas that are considered to be important. And there is a need 
for NMFS to demand it.
    The commenter stated that while the 2019 NWTT DSEIS/OEIS, in 
assessing environmental impacts on marine mammals, breaks down 
estimated impacts by population, little detail is provided about 
assumptions concerning modeled locations and times of year. See, e.g., 
DSEIS at 2-28 to 2-38 (e.g., defining numerous activities as simply 
occurring ``[o]ffshore''). The commenter further stated that the 
proposed rule notice adds nothing further, making it impossible for the 
public to assess the reasonableness of NMFS take estimates and 
negligible impact analysis in capturing the distribution of the 
activities proposed in the document. Additionally, the commenter 
asserts that the lack of definition in activity locations means that 
the agency cannot ensure takes are kept below authorized levels--and 
that sufficient measures are taken to protect particularly vulnerable 
marine mammal populations, such as the critically endangered Southern 
Resident killer whale and the struggling California gray whale.
    The commenter recommended that NMFS require the Navy to produce 
further information on modeled locations and, if activities are not 
limited through the authorization process to specific geographic areas, 
to determine a worst-case take estimate for each species or population.
    Another commenter stated that the Navy should provide NMFS with 
details on proposed timing of their training and testing activities and 
adjust the timing of their activities to minimize such overlap--such as 
through seasonal closures. The commenter stated that the DSEIS and the 
LOA application did not detail the times of year during which the 
proposed activities would take place. To issue a LOA, NMFS requires 
that proposed actions ``be well-planned with enough detailed 
information to allow for a robust analysis of the entire duration of 
your planned activity,'' which is lacking here. The Southern Resident 
killer whales have exhibited seasonality in their movements, and 
information from tagging studies, coastal surveys and passive acoustic 
monitoring allows some degree of understanding of seasonal areas for 
when and where they may be traveling and foraging. Any overlap in their 
seasonal movements and the Navy's testing and training activities will 
increase adverse impacts.
    Response: This final rule and the 2020 NWTT FSEIS/OEIS are 
structured to provide flexibility in training and testing locations, 
timing, and number. Many factors influence actual training and testing 
locations that cannot be predicted in advance (e.g., weather), so the 
analysis must allow for flexibility. The analysis must consider 
multiple Navy training and testing activities over large areas of the 
ocean for a seven-year period; therefore, analyzing activities in 
multiple locations over multiple seasons produces the best estimate of 
impacts/take to inform the 2020 NWTT FSEIS/OEIS and for NMFS to use to 
make its determinations. The scale at which spatially explicit density 
models are structured is determined by the data collection method and 
the environmental variables that are used to build the model. A number 
of variables that are meaningful to marine mammal species, such as sea 
surface temperature, do not vary or affect species on a fine scale. 
Expecting fine scale resolution from the Navy's density database may 
force artificial granularity on species for which it is not 
biologically meaningful at the population level. Therefore, given the 
variables that determine when and where the Navy trains and tests and 
the resolution of the density data, the analysis of potential impacts 
cannot be scaled to specific habitat areas, but the information 
included is at the appropriate resolution and provides the Navy and 
NMFS with the information necessary to determine potential impacts/take 
for a population of animals. Chapter 3.4 (Marine Mammals) of the 2020 
NWTT SFEIS/OEIS estimates what portion of impacts to each species are 
expected to occur within different regions in the Study Area. NMFS has 
reviewed and concurs with the Navy's analysis and level of detail 
provided given these restrictions.
    Additionally, specific modeled locations are not disclosed in 
public documents because of national security concerns, and information 
regarding the exact location of sonar usage is classified, although 
classified exercise reports with this information are provided to NMFS 
staff with the required security clearance. Furthermore, the Navy 
requires large areas of sea and air space to support the tactics, 
techniques, and procedures needed for certain activities, and training 
in large areas also helps the Navy avoid observation by potential 
adversaries. Modern sensing technologies make training on a large scale 
without observation more difficult. A foreign military's continual 
observation of U.S. Navy training in predictable (e.g., compiled and 
publicly disclosed) geographic areas and timeframes would enable 
foreign nations to gather intelligence and subsequently develop 
techniques, tactics, and procedures to potentially and effectively 
counter U.S. naval operations.
    Still, the Navy's rulemaking/LOA application and the 2020 NWTT 
FSEIS/OEIS provide a significant level of information about the 
locations of specific activities (see, e.g., Chapter 2 (Description of 
Proposed Action and Alternatives) and Appendix A (Activity 
Descriptions) of the FSEIS/OEIS), which NMFS has used in its analysis 
of Navy activities and their impacts to marine mammals in the NWTT 
Study Area. Chapter 2 of the 2020 NWTT FSEIS/OEIS also describes 
Standard Operating Procedures that may influence activity location. 
Additionally, this final rule, and Chapter 5 (Mitigation) and Appendix 
K (Geographic Mitigation Assessment) of the 2020 NWTT FSEIS/OEIS 
describe mitigation measures,

[[Page 72332]]

including in specific mitigation areas, that the Navy is required to 
implement during 2020-2027 NWTT activities. In addition to the above 
considerations, conservative assumptions are used in the quantitative 
assessment process, as described in the technical report titled 
Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods 
and Analytical Approach for Phase III Training and Testing (U.S. 
Department of the Navy, 2018c), an analysis which NMFS has reviewed and 
concurs with. The Navy also implements conservative application of 
marine mammal behavioral response data in the development of behavioral 
response criteria, as described in the technical report titled Criteria 
and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis 
(Phase III) (U.S. Department of the Navy, 2017h), which NMFS has also 
reviewed and concurs with. (Both technical reports are available at 
www.nwtteis.com.)
    Additionally, implementation of the adaptive management process 
under the Letters of Authorization issued under this final rule further 
ensures that the Navy does not exceed the level of authorized take. 
Finally, the Navy's classified exercise reports are required to include 
information regarding activities conducted and sound sources used 
within specific mitigation areas, which provides the sort of 
geographically-explicit information the commenter is referencing and 
may be used to inform the adaptive management process and future rules.
    Comment 14: A commenter stated that rather than using a fixed 
received level threshold for whether a take is likely to occur from 
exposure to mid-frequency sonar, the Navy has proposed a method for 
incorporating individual variation. Risk is predicted as a function of 
three parameters: (1) A basement value below which takes are unlikely 
to occur; (2) the level at which 50 percent of individuals would be 
taken; and (3) a sharpness parameter intended to reflect the range of 
individual variation. The commenter stated that even when parameters 
employed are based on the best available science, the implications of 
uncertainty in the values and biases and limitations in the model tend 
to lead to underestimation of the number of takes. The commenter 
asserts that data were incorrectly interpreted when calculating 
parameter values, resulting in a model that underestimates takes. The 
commenter states that errors included failure to recognize the 
difference between the mathematical basement plugged into the model, 
and the biological basement value, where the likelihood of observed and 
predicted takes becomes non-negligible; using the level where the 
probability of take was near 100 percent for the level where the 
probability of take was 50 percent; extrapolating values derived from 
laboratory experiments that were conducted on trained animals to wild 
animals without regard for the implications of training; and ignoring 
other available data, resulting in a further underestimation of takes. 
The commenter discusses several other points related to the 
development, interpretation, and application of the behavioral 
harassment thresholds used in prior Navy NWTT rules.
    Response: The commenter is referring to the Phase II behavioral 
criteria, which were utilized in the previous NWTT rulemaking (2015-
2020). In Phase III for this rulemaking, the Navy and NMFS incorporated 
the best available science into new BRFs that are described in the 
technical report titled Criteria and Thresholds for U.S. Navy Acoustic 
and Explosive Effects Analysis (Phase III) (U.S. Department of the 
Navy, 2017a), available at www.nwtteis.com. NMFS reviewed and concurs 
with the Phase III behavioral criteria described in the technical 
report.
    Comment 15: A commenter recommends that NMFS (1) specify the total 
numbers of model-estimated Level A harassment (PTS) and mortality takes 
rather than reduce the estimated numbers of takes based on the Navy's 
post-model analyses, (2) include the model-estimated Level A harassment 
and mortality takes in its negligible impact determination analyses, 
and (3) authorize the model-estimated Level A harassment and mortality 
takes if the respective negligible impact determinations are able to be 
made and, if not, require the Navy to implement additional measures to 
mitigate such takes.
    Another commenter stated that NMFS' post hoc adjustment for 
operational mitigation effectiveness is not a trivial or an abstract 
issue. It has the apparent effect of eliminating risk of mortality from 
explosives known to be of a power to kill marine mammals. Some experts 
have raised concerns that one Southern Resident killer whale mortality 
(whale L112) was caused by naval explosives or ordnance. NMFS should 
have made the Navy's approach transparent and explained the rationale 
for its acceptance of that approach. Its failure to do so has prevented 
the public from effectively commenting on its approach to this issue, 
in contravention of the APA, on a matter of obvious significance to the 
agency's core negligible impact findings. The commenter further states 
that, in estimating the number of instances of injury and mortality, 
NMFS makes two post hoc adjustments, significantly reducing the totals 
based on presumed animal avoidance and mitigation effectiveness. The 
commenter asserts that these two adjustments are arbitrary and non-
conservative.
    Response: First, we note that no mortality or non-auditory injury 
from exposure to explosives was modeled for any species in the NWTT 
Study Area, so the post-modeling approach was not applied in relation 
to mortality. Regarding the reference to concerns about the killer 
whale mortality, the comment references vague and unsupported claims 
that the author of a news article received from interviewees 
questioning a NMFS report. NMFS is unaware of information supporting 
the claim that Navy sonar or explosive use has caused the death of a 
killer whale.
    The consideration of marine mammal avoidance and mitigation 
effectiveness is integral to NMFS' and the Navy's overall analysis of 
impacts from sonar and explosive sources. NMFS has independently 
evaluated the method and agrees that it is appropriately applied to 
augment the model in the prediction and authorization of injury and 
mortality as described in the rule. Details of this analysis are 
provided in the Navy's 2018 technical report titled Quantifying 
Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and 
Analytical Approach for Phase III Training and Testing. Detailed 
information on the mitigation analysis was included in the proposed 
rule, including information about the technical report, and NMFS 
disagrees with the commenters' suggestions that there was not enough 
information by which to evaluate the Navy's post-modeling calculations 
or that the methods are arbitrary or non-conservative.
    Sound levels diminish quickly below levels that could cause PTS. 
Specifically, behavioral response literature, including the recent 3S 
studies (multiple controlled sonar exposure experiments on cetaceans in 
Norwegian waters) and SOCAL BRS studies (multiple cetacean behavioral 
response studies in Southern California), indicate that multiple 
species from different cetacean suborders do in fact avoid approaching 
sound sources by a few hundred meters or more, which would reduce 
received sound levels for individual marine mammals to levels below 
those that could cause PTS (see Appendix B of the Criteria and 
Thresholds for U.S. Navy Acoustic and Explosive Impacts to Marine 
Mammals and Sea Turtles

[[Page 72333]]

Technical Report (U.S. Department of the Navy, 2017) and Southall et 
al. (2019a)). The ranges to PTS for most marine mammal groups are 
within a few tens of meters and the ranges for the most sensitive 
group, the HF cetaceans, average about 200 m, to a maximum of 330 m in 
limited cases. For blue whales and other LF cetaceans, the range to PTS 
is 67 m for MF1 30 sec duration exposure, which is well within the 
mitigation zones for hull-mounted MFAS. Therefore, the anticipated 
avoidance to the distances discussed would greatly reduce the 
likelihood of impacts to hearing such as TTS and PTS. As discussed in 
the proposed rule, this final rule, and the Navy's report, animats in 
the Navy's acoustic effects model do not move horizontally or ``react'' 
to sound in any way. Accordingly, NMFS and the Navy's analysis 
appropriately applies a quantitative adjustment to the exposure results 
calculated by the model (which otherwise does not consider avoidance or 
mitigation).
    As discussed in the Navy's report, the Navy's acoustic effects 
model does not consider procedural mitigations (i.e., power-down or 
shut-down of sonars, or pausing explosive activities when animals are 
detected in specific zones adjacent to the source), which necessitates 
consideration of these factors in the Navy's overall acoustic analysis. 
Credit taken for mitigation effectiveness is extremely conservative. 
For example, if Lookouts can see the whole area, they get credit for it 
in the calculation; if they can see more than half the area, they get 
half credit; if they can see less than half the area, they get no 
credit. Not considering animal avoidance and mitigation effectiveness 
would lead to a great overestimate of injurious impacts. NMFS concurs 
with the analytical approach used, i.e., we believe the estimated take 
by Level A harassment numbers represent the maximum number of these 
takes that are likely to occur and it would not be appropriate to 
authorize a higher number or consider a higher number in the negligible 
impact analysis.
    The Navy assumes that Lookouts will not be 100 percent effective at 
detecting all individual marine mammals within the mitigation zones for 
each activity. This is due to the inherent limitations of observing 
marine species and because the likelihood of sighting individual 
animals is largely dependent on observation conditions (e.g., time of 
day, sea state, mitigation zone size, observation platform) and animal 
behavior (e.g., the amount of time an animal spends at the surface of 
the water). The Navy quantitatively assessed the effectiveness of its 
mitigation measures on a per-scenario basis for four factors: (1) 
Species sightability, (2) a Lookout's ability to observe the range to 
permanent threshold shift (for sonar and other transducers) and range 
to mortality (for explosives), (3) the portion of time when mitigation 
could potentially be conducted during periods of reduced daytime 
visibility (to include inclement weather and high sea-state) and the 
portion of time when mitigation could potentially be conducted at 
night, and (4) the ability for sound sources to be positively 
controlled (e.g., powered down). The Navy's report clearly describes 
how these factors were considered, and it is not necessary to view the 
many tables of numbers generated in the assessment to evaluate the 
method. Further, this information is not readily available in a format 
that could be shared and it would take extensive work to provide the 
necessary description of this data.
    The g(0) values used by the Navy for their mitigation effectiveness 
adjustments take into account the differences in sightability with sea 
state, and utilize averaged g(0) values for sea states of 1-4 and 
weighted as suggested by Barlow (2015). Using g(0) values is an 
appropriate and conservative approach (i.e., it underestimates the 
protection afforded by the Navy's mitigation measures) for the reasons 
detailed in the technical report. For example, during line-transect 
surveys, there are typically two primary observers searching for 
animals. Each primary observer looks for marine species in the forward 
90-degree quadrant on their side of the survey platform and scans the 
water from the vessel out to the limit of the available optics (i.e., 
the horizon). Because Navy Lookouts focus their observations on 
established mitigation zones, their area of observation is typically 
much smaller than that observed during line-transect surveys. The 
mitigation zone size and distance to the observation platform varies by 
Navy activity. For example, during hull-mounted mid-frequency active 
sonar activities, the mitigation zone extends 1,000 yd from the ship 
hull. During the conduct of training and testing activities, there is 
typically at least one, if not numerous, support personnel involved in 
the activity (e.g., range support personnel aboard a torpedo retrieval 
boat or support aircraft). In addition to the Lookout posted for the 
purpose of mitigation, these additional personnel observe for and 
disseminate marine species sighting information amongst the units 
participating in the activity whenever possible as they conduct their 
primary mission responsibilities. However, as a conservative approach 
to assigning mitigation effectiveness factors, the Navy elected to 
account only for the minimum number of required Lookouts used for each 
activity; therefore, the mitigation effectiveness factors may 
underestimate the likelihood that some marine mammals may be detected 
during activities that are supported by additional personnel who may 
also be observing the mitigation zone.
    Although the Navy Acoustic Effects Model (NAEMO) predicted PTS 
takes from the NWTT activities, no mortality or non-auditory injuries 
were predicted by NAEMO. For all of the reasons above, NMFS considers 
the estimated and authorized take (that was adjusted for aversion and 
mitigation) appropriate, and that is what has been analyzed in the 
negligible impact analysis. Accordingly, we decline the commenter's 
recommendation to analyze and authorize the model-estimated PTS, as it 
is neither expected to occur nor authorized. Given that we have 
declined a re-evaluation based on the PTS numbers the commenter 
recommends, the suggestion that we would subsequently then assess 
whether additional mitigation were necessary to satisfy the negligible 
impact standard is inapplicable. However, we reiterate that even when 
the estimated take has been determined to have a negligible impact on 
the affected species or stocks, it is still necessary, as a separate 
matter, to identify measures that will effect the least practicable 
adverse impact on the affected species or stocks and their habitat and, 
as described elsewhere, we have done so for this rule.
    Comment 16: A commenter stated that while the cause remains 
unknown, the skinniness and emaciation of stranded gray whales 
associated with the current UME strongly suggests a decline in prey 
availability. A previous die-off in 1998-2000 of gray whales was 
associated with strong El Ni[ntilde]o and La Ni[ntilde]a events and a 
regime shift in the benthic prey base of the Bering Sea. For the 
scientific community, the present-day concern is that warming seas--
caused by climate change--are reducing primary productivity in the 
whales' northern foraging range and that vanishing sea ice is 
constricting populations of ice-associated amphipods. If so, the die-
off may be a ``harbinger of things to come,'' in the words of one NOAA 
ecologist, a diminished, more tenuous future for the species rather 
than a one- or two-year anomaly.

[[Page 72334]]

    The commenter states that it is well established that animals 
already exposed to one stressor may be less capable of responding 
successfully to another; and that stressors can combine to produce 
adverse synergistic effects. Here, disruption in gray whale behavior 
can act adversely with the inanition caused by lack of food, increasing 
the risk of stranding and lowering the risk of survival in compromised 
animals. Further, starving gray whales may travel into unexpected areas 
in search of food--a likely contributing cause of some of the ship-
strikes observed in recently stranded animals. NMFS estimates that the 
Navy's activities will cause as many as 43 takes of gray whales each 
year, including 15 cases of temporary hearing loss caused by underwater 
explosives, indicating the potential for adverse interactions with 
nutritionally-stressed animals.
    The commenter states that in considering the effects of acoustic 
exposure on gray whales, NMFS must carefully consider the biological 
context of behavioral disruption in that species and evaluate the 
potential for severe consequences--including the clear potential 
mortality, which, in violation of the MMPA, is not authorized in the 
proposed rule.
    Response: This final rule includes 43 takes by Level B harassment 
of gray whales, less than one percent of the Eastern North Pacific 
stock, and no Level A harassment (PTS or non-auditory injury) of gray 
whales is anticipated or authorized. As discussed in the Analysis and 
Negligible Impact Determination section, the take by behavioral 
disturbance for any affected gray whale is expected to be at a moderate 
or low level and likely to occur on no more than one day within a year 
for any individual. Nonetheless, NMFS shares the commenter's concern 
for this stock given the UME and, as discussed in the Mitigation 
Measures section and elsewhere in this section, measures have been 
added since the proposed rule that are expected to further reduce the 
number and severity of the takes of gray whales. However, even if the 
impacts of the expected take was exacerbated by the compromised 
condition of a given individual, which could happen, there is no reason 
to expect that the level and severity of take anticipated to result 
from the Navy's activities would result in mortality as the commenter 
has suggested. Further, this gray whale stock is considered to be 
increasing.
    Further, the commenter incorrectly states that NMFS did not include 
mortality of gray whales in the proposed rule. The proposed rule, and 
this final rule, include one mortality over the seven years covered by 
this rule, or 0.14 mortality annually, which has been analyzed in the 
context of its impacts on the stock in the Analysis and Negligible 
Impact Determination section. However, this mortality is associated 
with ship strike, not behavioral disturbance, and given the severity 
and magnitude of the authorized Level B harassment take reiterated 
above, the effects of the take would not accumulate to impact annual 
rates of recruitment or survival.
    Comment 17: A commenter stated that by itself, NMFS' avoidance 
adjustment effectively reduces the number of estimated auditory 
injuries by 95 percent, on the assumption that marine mammals initially 
exposed to three or four sonar transmissions at levels below those 
expected to cause permanent injury would avoid injurious exposures. 
While it is certainly true that some marine mammals will flee the 
sound, there are no data to inform how many would do so, let alone that 
95 percent would move as expeditiously as the agency presumes. Marine 
mammals may remain in important habitat, and the most vulnerable 
individuals may linger in an area, notwithstanding the risk of harm; 
marine mammals cannot necessarily predict where an exercise will 
travel; and Navy vessels engaged in certain activities may move more 
rapidly than a marine mammal that is attempting to evacuate. Some 
commenters suggested that NMFS should not adjust for avoidance.
    Response: The consideration of marine mammals avoiding the area 
immediately around the sound source is provided in the Navy's 2018 
technical report titled Quantitative Analysis for Estimating Acoustic 
and Explosive Impacts to Marine Mammals and Sea Turtles and additional 
discussion is provided in NMFS' response to Comment 15. As the 
commenter correctly articulates: ``For avoidance, the Navy assumed that 
animals present beyond the range to onset PTS for the first three to 
four pings are assumed to avoid any additional exposures at levels that 
could cause PTS. That equated to approximately 5 percent of the total 
pings or 5 percent of the overall time active; therefore, 95 percent of 
marine mammals predicted to experience PTS due to sonar and other 
transducers were instead assumed to experience TTS.''
    As discussed in the Navy report, animats in the Navy's acoustic 
effects model do not move horizontally or ``react'' to sound in any 
way, necessitating the additional step of considering animal avoidance 
of close-in PTS zones. NMFS independently reviewed this approach and 
concurs that it is fully supported by the best available science. Based 
on a growing body of behavioral response research, animals do in fact 
avoid the immediate area around sound sources to a distance of a few 
hundred meters or more depending upon the species. Avoidance to this 
distance greatly reduces the likelihood of impacts to hearing such as 
TTS and PTS, respectively. Specifically, the ranges to PTS for most 
marine mammal groups are within a few tens of meters and the ranges for 
the most sensitive group, the HF cetaceans, average about 200 m, to a 
maximum of 270 m in limited cases. NMFS continues to consider the 
adjustments for avoidance appropriate and declines the recommendation 
that the adjustment not be included in the estimation of take.
    In regard to the comment about vessels moving faster than animals' 
ability to get out of the way, animals do not need to predict where an 
exercise will occur--in the vast majority of cases they can hear it 
coming. Further, the fact that vessels may move more rapidly than 
animals just makes it less likely that the animal would remain close 
enough to the source for the duration necessary to incur injury. NMFS 
and the Navy have appropriately considered animal movement in relation 
to testing and training activities and the commenter's observation does 
not necessitate any changes in our methods.
    Comment 18: A commenter recommends that NMFS ensure that its 
density estimates and abundance estimates used in the negligible impact 
determination analyses for harbor seals in Hood Canal, Washington 
Northern Inland Waters, and Southern Puget Sound are consistent, and if 
more recent abundance estimates from Navy monitoring efforts were used 
to inform the negligible impact determination analyses, use those same 
abundances estimates to inform its density estimates and re-estimate 
the numbers of takes accordingly. If NMFS intends to use the 
``instances of total takes as a percentage of the abundance'' in the 
final rule, the commenter recommends that it ensure that the abundance 
estimates, total takes, and instances of total takes as a percentage of 
the abundance are accurately stipulated for all three metrics in the 
relevant tables.
    Response: NMFS has updated the abundance estimates for inland 
stocks of harbor seals using data from Jefferson et al. (2017) and 
Smultea et al. (2017) in this final rule and the same has been done in 
the 2020 NWTT FSEIS/OEIS. The Analysis and Negligible Impact 
Determination section reflects these latest abundance estimates and 
includes

[[Page 72335]]

a complete explanation for how they were calculated. The new 
information does not change the in-water density estimates, and 
therefore the number of takes did not change.
    Comment 19: A commenter stated that as it has done for every Navy 
offshore range in its third round of MMPA authorizations, NMFS finds, 
notwithstanding a long record, that the Navy's use of active sonar 
would not result in a single instance of serious injury or mortality in 
any cetacean species. In doing so, the agency is at pains to dismiss 
the scientific literature. It spends almost five columns of the Federal 
Register notice characterizing the leading scientific explanation for 
sonar-related injuries in beaked whales--maladaptive behavioral 
response--as a mere ``hypothesis'' about which more information is 
needed. In this, it elides the obvious fact that this ``hypothesis'' is 
supported by numerous papers along multiple lines of evidence, 
including forensic investigations, laboratory study of organ tissue, 
and theoretical work on dive physiology, and plainly constitutes best 
available science. And it concludes by opining that, even if the 
``hypothesis'' were true, pathologies would occur only upon exposure 
``at very close range over a prolonged period of time,'' which, it 
says, would not happen here. It provides no evidence for this 
conclusion, which should not come as a surprise since it is 
contradicted by the agency's own investigations into at least two prior 
mass stranding events.
    The commenter stated that there is no question that sonar causes 
mortalities of beaked whales and other species, and that the severe 
injuries observed in beaked whales across multiple sonar-related 
mortality events occur independent of the animals' stranding. The 
commenter stated that NMFS' refusal to incorporate such impacts into 
its rulemaking violates the MMPA, which requires that decisions be 
based on best available science and which, consistent with the 1994 
Amendments to the Act, implicitly sets a probability standard of 
potentiality for takes resulting in serious injury and mortality.
    In a related comment, another commenter stated that while the Navy 
is aware of this correlation between sonar testing and stranded marine 
mammals, they choose to ignore the data and proceed with ``hopeful'' 
predictions that estimate no incidences of mortality or serious injury, 
despite contrary evidence from past use of sonar testing. The commenter 
states that the documented history of sonar related injuries and death 
cannot be ignored.
    Response: NMFS does not conclude that there is no possibility for 
mortality to occur as a result of the Navy's sonar activities, rather, 
we reason that consideration of all applicable information (the best 
available science) does not indicate that such mortality is reasonably 
likely to result from the Navy's activities within the seven-year span 
of the NWTT rule.
    NMFS has acknowledged that it is possible for naval activities 
using hull-mounted tactical sonar to contribute to the death of marine 
mammals in certain circumstances via strandings resulting from 
behaviorally mediated physiological impacts or other gas-related 
injuries. In the proposed rule, NMFS discussed these potential causes 
and outlined the few cases where active naval sonar (in the United 
States or, largely, elsewhere) had either potentially contributed to or 
(as with the Bahamas example) been more definitively causally linked 
with marine mammal mass strandings (more than two animals). There have 
been no documented mass strandings of beaked whales in the NWTT Study 
area since stranding data began to be collected.
    As discussed in the proposed rule and the Estimated Take of Marine 
Mammals section of this final rule, there are a suite of factors that 
have been associated with these specific cases of strandings directly 
associated with sonar (steep bathymetry, multiple hull-mounted 
platforms using sonar simultaneously, constricted channels, strong 
surface ducts, etc.) that are not present together in the NWTT Study 
Area and during the specified activities (and which the Navy takes care 
across the world not to operate under without additional monitoring). 
The number of incidences of strandings resulting from exposure to 
active sonar are few worldwide, there are no major training exercises 
utilizing multiple hull-mounted sonar in the NWTT Study Area, the 
overall amount of active sonar use is low relative to other Navy Study 
Areas, and there have not been any documented mass strandings of any 
cetacean species in the NWTT Study Area. Appropriately therefore, the 
Navy has not requested, and NMFS does not anticipate or authorize, 
incidental take by mortality of beaked whales or any other species as a 
result of sonar use.
    Comment 20: Some commenters stated that the Navy Acoustic Effects 
Model (NAEMO) has limitations as it does not consider social factors, 
and this is likely to result in the model underestimating takes (i.e., 
since Southern resident killer whales travel in groups, one whale 
ignoring noise while another avoids it would result in separation of 
individuals). Thus, either all whales would respond at the threshold 
for the most sensitive individual present, or stress rather than 
avoidance in some or most individuals would be the response. Another 
commenter suggested that NMFS does not consider calving cycles and 
migration in the analysis.
    In a related comment, a commenter stated that first, not only do 
takes occur at far greater distances than predicted by the Navy's risk 
model, the fact that larger areas are exposed to a given received level 
with increasing distance from the source further multiplies the number 
of takes. This implies takes of specific individuals will be of greater 
duration and be repeated more often, resulting in unexpectedly large 
cumulative effects. Second, corrections need to be made for bias, and 
corrections will need to be larger for species for which there are no 
data than for species for which there are poor data. Third, the greater 
range at which takes would occur requires more careful consideration of 
habitat-specific risks and fundamentally different approaches to 
mitigation.
    Response: The NAEMO brings together scenario simulations of the 
Navy's activities, sound propagation modeling, and marine mammal 
distribution (based on density and group size) by species or stock to 
model and quantify the exposure of marine mammals above identified 
thresholds for behavioral harassment, TTS, PTS, non-auditory injury, 
and mortality. It includes social factors (e.g., group sizes) typical 
of the species modeled. The Southern Resident killer whale densities 
inherently consider group size over large areas. We expect that on many 
days, the Navy's impacts will not affect Southern Resident killer 
whales, while on days that Southern Resident killer whales are 
affected, multiple individuals may be impacted, given group size. That 
said, all Southern Resident killer whale takes are expected to be takes 
by Level B harassment (behavioral disturbance and TTS) only.
    Regarding the commenter's assertion that NMFS and the Navy have 
mischaracterized either the size of the ensonified area or the number 
of animals that will be exposed, we disagree. As discussed in the 
technical report titled Quantifying Acoustic Impacts on Marine Mammals 
and Sea Turtles: Methods and Analytical Approach for Phase III Training 
and Testing (U.S. Department of the Navy, 2018) available at 
www.nwtteis.com, marine mammal density data are provided as a 10 x 10 
km grid in which each cell has a mean density and

[[Page 72336]]

standard error. In the NAEMO, species densities are distributed into 
simulation areas. Sixty distributions that vary based on the standard 
deviation of the density estimates are run per season (warm and cool) 
for each species to account for statistical uncertainty in the density 
estimate. The NAEMO also uses accepted propagation models and 
incorporates extensive databases of physical environmental data to 
accurately predict acoustic propagation, as described in this same 
technical report. This includes modeling for potential impacts at 
distances far from a sound source. The energy from multiple exposures 
during an event (e.g., multiple sonar pings) are accumulated to assess 
auditory impacts. Takes of individuals are accurately accounted for in 
the quantitative analysis as described in 2020 NWTT FSEIS/OEIS and the 
above supporting technical report.
    The Navy compiled data from multiple sources and developed a 
protocol to select the best available density estimates based on 
species, area, and time (i.e., season), including those for species 
with poor data. This process is described in the technical report 
titled U.S. Navy Marine Species Density Database Phase III for the 
Northwest Training and Testing Study Area (U.S. Department of the Navy, 
2019), available at www.nwtteis.com.
    The commenter notes ``larger areas are exposed to a given received 
level with increasing distance from the source further multiplies the 
number of takes,'' seeming to suggest that this means that the take 
estimates should be higher than they are. However, this comment does 
not account for the behavioral harassment thresholds used by NMFS and 
the Navy, which include both BRFs describing how a smaller portion of 
exposed animals respond in a manner that qualifies as a take at lower 
received levels, as well as distance cutoffs--both of which counter the 
assertion that large numbers of animals will be taken at increasing 
distances from the source.
    Regarding the comment about mitigation, while there is no specific 
recommendation, we note that NMFS has worked with the Navy to carefully 
consider the risks and to develop a suite of mitigation measures to 
avoid or reduce potential impacts to species (such as the Southern 
Resident killer whale) and their habitat to the maximum extent 
practicable, including numerous new mitigation measures developed for 
the final rule.
    All models have limitations, and there is no way to fully 
incorporate all of the interactions of the biotic and abiotic 
components of a living system into a model. However, the Navy and NMFS 
have used the best available science in the approach outlined for this 
rule, and appropriately incorporated consideration of marine mammal 
social dynamics, as well as the likely area of ensonification, in the 
model used in the estimation of take. Further, the Potential Effects of 
Specified Activities on Marine Mammals and their Habitat section in the 
proposed rule included a comprehensive discussion of the different ways 
that marine mammals have been observed to respond to acoustic stimuli 
(e.g., separation) and NMFS used this information qualitatively in 
addition to the quantitative modeling results to evaluate the impacts 
of anticipated take on individuals and the species or stock in the 
Analysis and Negligible Impact Determination section. Also, where 
available, other information regarding biologically important areas and 
times was considered in the development of mitigation measures.
    Comment 21: A commenter stated that the proposed rule did not 
incorporate the latest, most seasonally specific distribution and 
hotspot information for Southern Resident killer whales. In particular, 
the commenter asserted that NMFS does not specifically propose to use 
recent monitoring evidence from NOAA's hydrophone network in its 
analysis. While the Navy did propose to work with NMFS to determine the 
likelihood of gray whale and Southern Resident killer whale presence, 
the commenter asserted that NMFS does not require itself or the Navy to 
rely on NOAA's hydrophone network. This omission is of particular 
concern because NOAA's monitoring shows considerable temporal and 
spatial overlap between high-use testing areas for active sonar and 
explosives and high-use areas by Southern Resident killer whales off 
Washington's north coast.
    Response: The Navy and NMFS used the best available science 
regarding distribution and hotspots of Southern Resident killer whales 
both in the density numbers that informed the take estimates, as well 
as in the consideration of mitigation. The data the commenter is 
noting, Emmons et al., 2019 (which is Navy-funded work utilizing the 
referenced hydrophones) was considered in both this final rule and the 
2020 NWTT FSEIS/OEIS. The commenter has suggested that the Cape 
Flattery Offshore region is a ``high use'' area for the Navy based on 
findings from Emmons et al. (2019) and suggests that the Navy consider 
moving activities away from the Cape Flattery area in the spring 
(April, May, and June) when Southern Resident killer whale detections 
are highest. The Navy has clarified that it does not frequently conduct 
training or testing activities in the location of the Cape Flattery 
Offshore hydrophone since that area is highly utilized by commercial 
vessel traffic, making it an undesirable location for the Navy to 
conduct activities, especially sonar training or testing. Emmons et al. 
(2019) reported a number of sonar detections at the Cape Flattery 
Offshore hydrophone, but this was not normalized for effort, which was 
also highest at the Cape Flattery Offshore hydrophone location, which 
could have the effect of overstating detections in that area. Further, 
Emmons et al. (2019) reported on detections of mid-frequency active 
sonar, but did not distinguish between various sources (U.S. versus 
Canadian navies, among other users). Historically, the annual usage of 
MF1 sonar by the U.S. Navy in the Olympic Coast National Marine 
Sanctuary (which overlaps with the Cape Flattery Offshore hydrophone) 
over the last 10 years has been minimal. As described in the Mitigation 
Measures section, NMFS and the Navy developed additional mitigation 
measures to further avoid or reduce potential impacts from the Navy's 
activities on Southern Resident killer whales and other marine species 
in key foraging, breeding, and migration habitat areas. For example, 
NMFS and the Navy have included a new mitigation area known as the Juan 
de Fuca Eddy Marine Species Mitigation Area, which encompasses waters 
off Cape Flattery as recommended by the commenter. The Navy's 
mitigation now includes annual limits on hull-mounted mid-frequency 
active sonar and prohibits explosive Mine Countermeasures and 
Neutralization Testing in the Juan de Fuca Eddy Marine Species 
Mitigation Area. All other explosive activities are required to be 
conducted 50 nmi from shore in the Marine Species Coastal Mitigation 
Area. In addition, NMFS and the Navy developed a new mitigation for the 
Navy to issue annual awareness notification messages to alert Navy 
ships and aircraft to the possible presence of increased concentrations 
of Southern Resident killer whales seasonally, which will further help 
avoid potential impacts from vessel movements and training and testing 
activities on this stock.
    Comment 22: A commenter stated that Tables 19-31 fail to include 
effects from ASW2 mid-frequency sonar on marine mammals. Although it 
appears that such tests will only occur 12 or more nmi offshore, the 
distribution of Southern

[[Page 72337]]

Resident killer whales and many other cetaceans still have considerable 
potential overlap with that zone. The commenter stated that NMFS must 
require the Navy to provide a table showing the ranges to temporary and 
permanent threshold shifts for the ASW2 sonar bin and clarify the 
predicted effects on marine mammals before approving the use of such 
sonar/activities.
    Response: The range to impact tables that the commenter references 
are provided for the most impactful activities, and ASW2 sonar is not 
one of the most impactful activities. The Navy has provided, and NMFS 
has presented, information on representative bins from the Navy's 
activities to demonstrate the ranges to impacts for marine mammals. The 
Navy is unable to provide information on ranges to impact for bins that 
are classified, including ASW2 sonar. The Navy has reviewed the 
scenarios and events associated with the ASW2 bin and there are zero 
estimated Southern Resident killer whale exposures. NMFS has carefully 
reviewed this information and the Navy's methods and concurs with this 
conclusion.

Mitigation and Monitoring

Least Practicable Adverse Impact Determination
    Comment 23: A commenter recommends that NMFS clearly separate its 
application of the least practicable adverse impact requirement from 
its negligible impact determination. Once NMFS determines that an 
applicant's proposed activities would have a negligible impact, it 
still has a responsibility to determine whether the activities would 
nevertheless have adverse impacts on marine mammal species and stocks 
and their habitat. If so, NMFS must condition the authorization to 
eliminate or reduce those impacts whenever, and to the greatest extent, 
practicable. As the statue is written, it is inappropriate to conflate 
the two standards, as NMFS seems to be doing.
    Response: NMFS has made clear in this and other rules that the 
agency separates its application of the least practicable adverse 
impact requirement in the Mitigation Measures section from its 
negligible impact analyses and determinations for each species or stock 
in a separate section. Further, NMFS has made this separation clear in 
practice for years by requiring mitigation measures to reduce impacts 
to marine mammal species and stocks and their habitat for all projects, 
even those for which the anticipated take would clearly have a 
negligible impact, even in the absence of mitigation.
    Comment 24: A commenter recommends that NMFS follow an analysis 
consisting of three elements to (1) determine whether the impacts of 
the proposed activities are negligible at the species or stock level, 
(2) if so, determine whether some of those impacts nevertheless are 
adverse either to marine mammal species or stocks or to key marine 
mammal habitat, and (3) if so, determine whether it is practicable for 
the applicant to reduce or eliminate those impacts through modifying 
those activities or by other means (e.g., requiring additional 
mitigation measures to be implemented).
    Response: In the Mitigation Measures section of the rule, NMFS has 
explained in detail our interpretation of the least practicable adverse 
impact standard, the rationale for our interpretation, and then how we 
implement the standard. The method the agency is using addresses all of 
the necessary components of the standard and produces effective 
mitigation measures that result in the least practicable adverse impact 
on both the species or stocks and their habitat. The commenter has 
failed to illustrate why NMFS' approach is inadequate or why the 
commenter's proposed approach would be better, and we therefore decline 
to accept the recommendation.
    Comment 25: A commenter recommended that NMFS rework its evaluation 
criteria for applying the least practicable adverse impact standard to 
separate the factors used to determine whether a potential impact on 
marine mammals or their habitat is adverse and whether possible 
mitigation measures would be effective.
    Response: In the Mitigation Measures section, NMFS has explained in 
detail our interpretation and application of the least practicable 
adverse impact standard. The commenter has recommended an alternate way 
of interpreting and implementing the least practicable adverse impact 
standard, in which NMFS would consider the effectiveness of a measure 
in our evaluation of its practicability. The commenter erroneously 
asserts that NMFS currently considers the effectiveness of a measure in 
a determination of whether the potential effects of an activity are 
adverse, but the commenter has misunderstood NMFS' application of the 
standard--rather, NMFS appropriately considers the effectiveness of a 
measure in the evaluation of the degree to which a measure will reduce 
adverse impacts on marine mammal species or stocks and their habitat, 
as a less effective measure will less successfully reduce these impacts 
on marine mammals. Further, the commenter has not provided information 
that shows that their proposed approach would more successfully 
evaluate mitigation under the LPAI standard, and we decline to accept 
it.
    Comment 26: A commenter stated that although NMFS has written 
extensively on the least practicable adverse impact standard, it 
remains unclear exactly how each authorization's proposed ``mitigation 
measures are sufficient to meet the statutory legal standard,'' or even 
what standard NMFS is using. As such, the commenter recommends that 
NMFS address these shortcomings by adopting a simple, two-step analysis 
that more closely tracks the statutory provisions being implemented. 
The first step should be to identify impacts on marine mammal species 
or stocks or their habitat that, although negligible, are nevertheless 
adverse. If such impacts are identified, then NMFS must identify and 
require the applicant to adopt measures to reduce those impacts to the 
lowest level practicable. If NMFS is using some other legal standard to 
implement the least practicable adverse impact requirements, the 
commenter further recommends that NMFS provide a clear and concise 
description of that standard and explain why it believes it to be 
``sufficient'' to meet the statutory legal requirements.
    Response: NMFS disagrees with the commenter's assertion that 
analysis of the rule's mitigation measures under the least practicable 
adverse impact standard remains unclear or that the suggested 
shortcomings exist. Further, the commenter provides no rationale as to 
why the two-step process they describe is better than the process that 
NMFS uses to evaluate the least practicable adverse impact that is 
described in the rule, and therefore we decline to accept the 
recommendation.
    Comment 27: Regarding the habitat component of the least 
practicable adverse impact standard, a commenter recommended that NMFS 
(1) adopt a clear decision-making framework that recognizes the species 
and stock component and the marine mammal habitat component of the 
least practicable adverse impact provision and (2) always consider 
whether there are potentially adverse impacts on marine mammal habitat 
and whether it is practicable to minimize them. The MMPA requires that 
NMFS address both types of impacts, not that there be no overlap 
between the mitigation measures designed to reduce those impacts.

[[Page 72338]]

    Response: NMFS' decision-making framework for applying the least 
practicable adverse impact standard clearly recognizes the habitat 
component of the provision (see the Mitigation Measures section of the 
rule). NMFS does always consider whether there are adverse impacts on 
habitat and how they can be mitigated. Marine mammal habitat value is 
informed by marine mammal presence and use and, in some cases, there 
may be overlap in measures for the species or stock directly and for 
use of habitat. In this rule, we have required time-area mitigation 
measures based on a combination of factors that include higher 
densities and observations of specific important behaviors of marine 
mammal species themselves, but also that clearly reflect preferred 
habitat (e.g., feeding habitat in the Juan de Fuca Eddy Marine Species 
Mitigation Area and areas that have also been designated as Southern 
Resident killer whale critical habitat in the Puget Sound and Strait of 
Juan de Fuca Mitigation Area). In addition to being delineated based on 
physical features that drive habitat function (e.g., bathymetric 
features), the high densities and concentration of certain important 
behaviors (e.g., reproduction, feeding, resting) in these particular 
areas clearly indicate the presence of preferred habitat. The MMPA does 
not specify that effects to habitat must be mitigated in separate 
measures, and NMFS has clearly included measures that provide 
significant reduction of impacts to both marine mammal species or 
stocks and their habitat, as required by the statute.
    Comment 28: A commenter cited two judicial decisions and commented 
that the ``least practicable adverse impact'' standard has not been 
met. The commenter stated that contrary to the Pritzker Court decision, 
NMFS, while clarifying that population-level impacts are mitigated 
``through the application of mitigation measures that limit impacts to 
individual animals,'' has again set population-level impact as the 
basis for mitigation in the proposed rule. Because NMFS' mitigation 
analysis is opaque, it is not clear what practical effect this position 
may have on its rulemaking. The commenter stated that the proposed rule 
is also unclear in its application of the ``habitat'' emphasis in the 
MMPA's mitigation standard, and that while NMFS' analysis is opaque, 
its failure to incorporate or even, apparently, to consider viable 
time-area measures suggests that the agency has not addressed this 
aspect of the Pritzker decision. The commenter argued that the MMPA 
sets forth a ``stringent standard'' for mitigation that requires the 
agency to minimize impacts to the lowest practicable level, and that 
the agency must conduct its own analysis and clearly articulate it and 
not just parrot what the Navy says. The baselessness of this approach 
can be seen from the outcome of the Conservation Council decision, 
where the parties were able to reach a settlement agreement 
establishing time-area management measures, among other things, on the 
Navy's Southern California and Hawaii Range Complexes notwithstanding 
NMFS' finding, following the Navy, that all such management measures 
would substantially affect military readiness and were not practicable. 
Unfortunately, there is no indication in the proposed rule that NMFS 
has, as yet, done anything different here.
    Another commenter stated that NMFS ``cannot just parrot what the 
Navy says'' with respect to analysis of the practicability of 
mitigation measures, in reference to the opinion in Conservation 
Council for Hawaii v. Nat'l Marine Fisheries Serv. The commenter 
asserts that in the proposed rule, NMFS has done little more than 
parrot the Navy's position on mitigation for actions in the NWTT Study 
Area, asserting an independent review of the Navy's assertions of 
impracticability but providing no substantiation of that review. The 
commenter states that even if NMFS did conduct such a review, NMFS 
failed to consider and implement additional mitigation measures that 
are both practicable and effective to reduce the adverse impacts to 
marine mammals in the NWTT Study Area.
    The commenter stated that it commented on the NWTT DSEIS and the 
Navy's request for authorization that outlined specific mitigation 
measures the Navy could incorporate into its training and testing 
activities. More specifically, the commenter states that it suggested 
that NMFS consider seasonal closures based on Southern Resident killer 
whale presence, require additional mitigation in the Southern Resident 
killer whale offshore habitat area, use of real-time whale reporting, 
and additional mitigation measures regarding impulsive sound and sonar 
exposure. The commenter stated that NMFS did not assess or incorporate 
these practicable and effective mitigation measures.
    Response: First, the commenter's reference to mitigation measures 
implemented pursuant to a prior settlement agreement is entirely 
inapplicable to a discussion of NMFS' responsibility to ensure the 
least practicable adverse impact under the MMPA. Specifically, for 
those areas that were previously covered under the 2015 settlement 
agreement for the HSTT Study Area, it is essential to understand that: 
(1) The measures were developed pursuant to negotiations with the 
plaintiffs and were specifically not selected and never evaluated based 
on an examination of the best available science that NMFS otherwise 
applies to a mitigation assessment and (2) the Navy's agreement to 
restrictions on its activities as part of a relatively short-term 
settlement (which did not extend beyond the expiration of the 2013 
regulations) did not mean that those restrictions were practicable to 
implement over the longer term.
    Regarding the remainder of the comments, NMFS disagrees with much 
of what the commenters assert. First, we have carefully explained our 
interpretation of the least practicable adverse impact standard and how 
it applies to both stocks and individuals, including in the context of 
the Pritzker decision, in the Mitigation Measures section. Further, we 
have applied the standard correctly in this rule in requiring measures 
that reduce impacts to individual marine mammals in a manner that 
reduces the probability and/or severity of population-level impacts.
    When a suggested or recommended mitigation measure that would 
reduce impacts is not practicable, NMFS has explored variations of that 
mitigation to determine if a practicable form of related mitigation 
exists. This is clearly illustrated in NMFS' independent mitigation 
analysis process explained in the Mitigation Measures section of the 
final rule. First, some types of mitigation required under this rule 
are area-specific and vary by mitigation area, demonstrating that NMFS 
has engaged in a site-specific analysis to ensure mitigation is 
tailored when practicability demands, i.e., some forms of mitigation 
were practicable in some areas but not others. For instance, while it 
was not practicable for the Navy to prohibit surface ship hull-mounted 
MF1 mid-frequency active sonar during training or testing in all 
mitigation areas, NMFS did prohibit its use during all training and 
testing in the Point St. George Humpback Whale Mitigation Area, 
effective July 1 to November 30, and included caps on MF1 sonar use in 
the Olympic Coast National Marine Sanctuary Mitigation Area, the Juan 
de Fuca Eddy Marine Species Mitigation Area, and in the Marine Species 
Coastal Mitigation Area.
    Regarding the comment about mitigation of habitat impacts, marine 
mammal habitat value is informed by

[[Page 72339]]

marine mammal presence and use and, in some cases, there may be overlap 
in measures for the species or stock directly and for use of habitat. 
In this rule, we have required time-area mitigations based on a 
combination of factors that include higher densities and observations 
of specific important behaviors of marine mammals themselves, but also 
that clearly reflect preferred habitat (e.g., humpback whale feeding 
habitat in the Stonewall and Heceta Bank Humpback Whale Mitigation Area 
and gray whale feeding habitat in Northern Puget Sound Gray Whale 
Mitigation Area). In addition to being delineated based on physical 
features that drive habitat function (e.g., bathymetric features), the 
high densities and concentration of certain important behaviors (e.g., 
breeding, resting) in these particular areas clearly indicate the 
presence of preferred habitat. The commenter seems to suggest that NMFS 
must always consider separate measures aimed at marine mammal habitat; 
however, the MMPA does not specify that effects to habitat must be 
mitigated in separate measures, and NMFS has clearly identified 
measures that provide significant reduction of impacts to both ``marine 
mammal species and stocks and their habitat,'' as required by the 
statute.
    NMFS agrees, however, that the agency must conduct its own 
analysis, which it has done here, and not just accept what is provided 
by the Navy. That does not mean, however, that NMFS cannot review the 
Navy's analysis of effectiveness and practicability of its proposed 
mitigation measures, which by regulation the Navy was required to 
submit with its application, and concur with those aspects of the 
Navy's analysis with which NMFS agrees. The commenters seem to suggest 
that NMFS must describe in the rule in detail the rationale for not 
adopting every conceivable permutation of mitigation, which is neither 
reasonable nor required by the MMPA. NMFS has described our well-
reasoned process for identifying the measures needed to meet the least 
practicable adverse impact standard in the Mitigation Measures section 
in this rule, and we have followed the approach described there when 
analyzing potential mitigation for the Navy's activities in the NWTT 
Study Area. Responses to specific recommendations for mitigation 
measures provided by the commenters are discussed separately.
    Regarding the commenter's statement that it commented on the NWTT 
DSEIS and the Navy's request for authorization with specific mitigation 
measures the Navy could incorporate into its training and testing 
activities, as noted above this final rule includes numerous additional 
mitigation measures, which are also included in the 2020 NWTT FSEIS/
OEIS. For example, this final rule includes a new mitigation area in 
the NWTT Offshore Area, the Juan de Fuca Eddy Marine Species Mitigation 
Area, where the Navy will implement sonar restrictions and prohibit 
explosive mine countermeasure and neutralization activities to further 
avoid potential impacts on Southern Resident killer whales and humpback 
whales. In NWTT Inland Waters, the Navy will initiate communication 
with the appropriate marine mammal detection networks prior to certain 
activities, such as Civilian Port Defense--Homeland Security Anti-
Terrorism/Force Protection Exercises and Small Boat Attack Exercises, 
to further avoid potential impacts on Southern Resident killer whales 
and gray whales.
    Comment 29: A commenter stated that since NMFS has expounded on the 
least practicable adverse impact standard at some length in a series of 
proposed authorizations, it has been an evolutionary process that 
varies depending on each specific situation. The commenter recommends 
that NMFS adopt general regulations to govern the process and set forth 
the basic steps and criteria that apply across least practicable 
adverse impact determinations. Those standards should not be shifting 
on a case by-case basis, as now appears to be the case. Rather, the 
analytical framework and decision-making standards should be consistent 
across authorizations. Variations between authorizations should be 
based on the facts underlying each application, not the criteria that 
underpin the least practicable adverse impact standard.
    Response: The commenter misunderstands the agency's process. 
Neither the least practicable adverse impact standard nor NMFS' process 
for evaluating it shifts on a case-by-case basis. Rather, as the 
commenter suggests should be the case, the evaluation itself is case-
specific to the proposed activity, the predicted impacts, and the 
mitigation under consideration.
    Regarding the recommendation to adopt general regulations, we 
appreciate the recommendation and may consider the recommended approach 
in the future. However, providing directly relevant explanations of 
programmatic approaches or interpretations related to the incidental 
take provisions of the MMPA in a proposed incidental take authorization 
is an effective and efficient way to provide information to and solicit 
focused input from the public. Further, this approach affords the same 
opportunities for public comment as a stand-alone rulemaking would.
    Comment 30: A commenter stated that the Navy fails to establish 
that its harassment is the least practicable method to conduct its 
research. The commenter states that the MMPA mandates a finding that 
the planned activities ``. . . effect the least practicable impact on 
such species or stock and its habitat. . . .'' The commenter asserted 
that the Level A and Level B harassment that the Navy predicts will 
occur includes heavy use of sonar technology that has been correlated 
with the deaths and strandings of thousands of whales and dolphins 
during the past 20 years. The commenter further stated that the Navy 
fails to address how its proposed activities lessen the threat of 
injury and death. Akin to its failure to address population and 
abundance, the commenter says that the Navy fails to consider how 
decisions involving geography, timing, and other factors might lessen 
the ill effects of its actions.
    Response: NMFS' application of the least practicable adverse impact 
standard is described in the Implementation of Least Practicable 
Adverse Impact Standard section of this final rule. This final rule 
requires the Navy to implement extensive mitigation measures to achieve 
the least practicable adverse impacts on the species and stocks of 
marine mammals and their habitat, including measures that are specific 
to certain times and areas as the commenter suggests, and including 
additional measures that have been added since the proposed rule. 
Mitigation measures include procedural mitigation measures, such as 
required shutdowns and delays of activities if marine mammals are 
sighted within certain distances, and geographic area mitigation 
measures, including limitations on activities such as sonar in areas 
that are important for certain behaviors such as feeding. These 
mitigation measures were designed to lessen the frequency and severity 
of impacts from the Navy's activities on marine mammals and their 
habitat, and ensure that the Navy's activities have the least 
practicable adverse impact on species and stocks. See the Mitigation 
Measures section of this final rule for additional detail on specific 
procedural mitigation measures and measures in mitigation areas.
    Additionally, we disagree with the implications of the commenter's 
statement regarding ``the strandings of thousands of whales and 
dolphins''

[[Page 72340]]

being associated with the use of sonar. Please see the Stranding and 
Mortality section in the proposed rule for an accurate characterization 
of the far lower number of instances in which naval activities have 
been causally associated with marine mammal strandings. That section 
included an extensive discussion assessing the potential for Navy 
activities to result in stranding, and NMFS' response to Comment 19 
describes why we do not expect the Navy's NWTT activities to result in 
the stranding or death of marine mammals from sonar use.

Mitigation Areas

    Comment 31: A commenter recommended that NMFS expand the proposed 
mitigation measures to more comprehensively protect humpback whales at 
Stonewall and Heceta Bank between May and November. The commenter 
recommended that air-deployed mid-frequency active sonar (i.e., dipping 
sonar) should be prohibited, as well as other activities involving 
sources of mid-frequency active sonar, including unit-level training 
and maintenance and system checks while vessels are in transit. The 
commenter states that expanded mitigation measures would benefit a 
variety of species, including noise-sensitive harbor porpoise, that are 
likely to be found in relatively higher densities within the Mitigation 
Area. The commenter recommended that NMFS also include mitigation 
measures that limit vessel speeds to reduce the likelihood of vessel 
strike.
    Response: This final rule prohibits the Navy from conducting 
surface ship hull-mounted MF1 mid-frequency active sonar during 
training or testing activities in the Stonewall and Heceta Bank 
Humpback Whale Mitigation Area (effective May 1 to November 30), as 
included in the proposed rule. Additionally, this final rule includes 
new mitigation which prohibits the Navy from conducting more than a 
total of 33 hours of surface ship hull-mounted MF1 mid-frequency active 
sonar during testing annually within 20 nmi from shore in the Marine 
Species Coastal Mitigation Area (which includes a portion of the 
Stonewall and Heceta Bank Humpback Whale Mitigation Area), the Juan de 
Fuca Eddy Marine Species Mitigation Area, and the Olympic Coast 
National Marine Sanctuary Mitigation Area combined. This measure is 
effective year round. Previously the proposed rule restricted the Navy 
to 33 hours of MF1 sonar annually within only the Olympic Coast 
National Marine Sanctuary Mitigation Area (excluding the portion of the 
mitigation area that overlapped the Quinault Range Site).
    Additionally, regarding the use of dipping sonar, throughout the 
NWTT Study Area the Navy plans to conduct no more than one hour of MF4 
sonar (helicopter-deployed dipping sonar) per year during training 
events over the seven-year duration of this final rule. Additionally, 
the Navy plans to conduct no more than 50 hours of MF4 sonar per year 
during testing events over the seven-year duration of this rule. Given 
the amount of dipping sonar and comparatively low associated impacts to 
marine mammals, along with the impracticability of including more 
restrictions, additional mitigation specific to dipping sonar is not 
warranted.
    Additional geographic mitigation measures for active sonar beyond 
what is detailed in the Mitigation Areas section of this final rule and 
Section K.3 (Mitigation Areas to be Implemented) of the 2020 NWTT 
FSEIS/OEIS, such as prohibiting additional types of active sonar or 
further limiting active sonar hours in the Stonewall and Heceta Bank 
Humpback Whale Mitigation Area, would be impractical to implement for 
the reasons described in Appendix K (Geographic Mitigation Assessment) 
and Section 5.5.1 (Active Sonar) of the 2020 NWTT FSEIS/OEIS. NMFS has 
carefully reviewed this information and determined that additional 
mitigation measures would be impracticable.
    Potential vessel speed restrictions in the NWTT Study Area are 
addressed in our response to Comment 38. Please refer to that comment 
for our full response.
    Comment 32: A commenter stated that NMFS should expand the proposed 
mitigation measures to more comprehensively protect humpback whales at 
Point St. George Humpback Whale Mitigation Area between July and 
November. The commenter asserted that within the area the agency should 
prohibit air-deployed mid-frequency active sonar (i.e., dipping sonar), 
as well as other activities involving sources of mid-frequency active 
sonar, including unit-level training and maintenance and system checks 
while vessels are in transit. NMFS should also include mitigation 
measures that limit vessel speeds to reduce the likelihood of vessel 
strike.
    Response: This final rule includes new mitigation limiting the Navy 
to a total of 33 hours of surface ship hull-mounted MF1 mid-frequency 
active sonar during testing annually within 20 nmi from shore in the 
Marine Species Coastal Mitigation Area, the Juan de Fuca Eddy Marine 
Species Mitigation Area, and the Olympic Coast National Marine 
Sanctuary Mitigation Area combined. The expanded mitigation will offer 
additional protections for humpback whales in the portion of the Marine 
Species Coastal Mitigation Area that overlaps the Point St. George 
Humpback Whale Mitigation Area. Additional geographic mitigation 
measures for active sonar beyond what is detailed in the Mitigation 
Areas section of this final rule and Section K.3 (Mitigation Areas to 
be Implemented) of the 2020 NWTT FSEIS/OEIS, such as further expanding 
mitigation requirements in the Point St. George Humpback Whale 
Mitigation Area, would be impractical to implement for the reasons 
described in Appendix K (Geographic Mitigation Assessment) and Section 
5.5.1 (Active Sonar) of the 2020 NWTT FSEIS/OEIS. NMFS has carefully 
reviewed this information and determined that additional mitigation 
measures would be impracticable.
    Throughout the NWTT Study Area, the Navy plans to conduct no more 
than one hour of MF4 sonar (helicopter-deployed dipping sonar) per year 
during training events over the seven-year duration of this final rule. 
Additionally, the Navy plans to conduct no more than 50 hours of MF4 
sonar per year during testing events over the seven-year duration of 
this rule. Please see the response to Comment 52 for additional 
information. Given the amount of dipping sonar and comparatively low 
associated impacts to marine mammals, along with the impracticability 
of including more restrictions, additional mitigation specific to 
dipping sonar is not warranted.
    Potential vessel speed restrictions in the NWTT Study Area are 
addressed in our response to Comment 38. Please refer to that comment 
for our full response.
    Comment 33: A commenter recommended that NMFS engage with the Navy 
in a more rigorous analysis of alternatives and mitigation options in 
the Puget Sound and Strait of Juan de Fuca Mitigation Area (year-
round), with the aim of eliminating potential impacts on Southern 
Resident killer whales. The commenter recommended that NMFS (1) 
completely prohibit activity during periods of higher residency or 
occurrence of the population, viz., roughly May through October for the 
Salish Sea (another commenter recommended all year round) and roughly 
October through mid-February for the inland waters of Puget Sound (2) 
require noise isolation, particularly for activities such as pierside 
testing and maintenance that are concentrated in particular locations 
(3) set a transparent,

[[Page 72341]]

rigorous protocol for ensuring that Southern Resident killer whales 
will not be exposed to noise that can cause behavioral disruption, 
before an activity proceeds, including by using the region's existing 
real-time hydrophone networks and by establishing additional hydrophone 
sites in key areas as needed; and (4) consider measures to mitigate the 
impacts of the Navy's Growler overflights on Southern Resident killer 
whales and other marine species. The commenter stated that the mere 
assurance that Navy biologists will work with NMFS to determine the 
likelihood of species occurrence--a statement that does not imply use 
of any real-time detection systems--is plainly not sufficient. The 
commenter stated that NMFS should consider the likelihood of humpback 
whale presence in the planned training location, in addition to gray 
whales and Southern Residents, in prescribing mitigation. The commenter 
recommended that NMFS also include mitigation measures that limit 
vessel speeds in the area to reduce the likelihood of vessel strike. 
Another commenter noted that NMFS does not require the use of publicly 
available whale sighting data to reduce the chance of negative 
interactions between the Navy and marine mammals.
    Response: The majority of locations in which training and testing 
activities occur within the NWTT Inland Waters do not overlap areas 
where Southern Resident killer whales occur. For instance, most 
training and testing occurs in the Hood Canal at Naval Base Kitsap 
Bangor and Dabob Bay Range, around Keyport, and Bremerton. None of 
these locations have had sightings of Southern Resident killer whales 
in over 20 years. The only locations with the potential to affect 
Southern Resident killer whales are training events conducted at 
Everett, in Crescent Harbor and which use Navy 3 OPAREA and Navy 7 
OPAREA.
    The Mitigation Areas section of this final rule and Section K.3.3. 
(Mitigation Areas for Marine Species in NWTT Inland Waters) of the 2020 
NWTT FSEIS/OEIS include enhanced mitigation measures in NWTT Inland 
Waters for Southern Resident killer whales, gray whales, humpback 
whales, and other marine species. See the Changes from the Proposed 
Rule to the Final Rule and Mitigation Measures sections of this rule 
for a full discussion of these new measures. The new measures in the 
Puget Sound and Strait of Juan de Fuca Mitigation Area since 
publication of the proposed rule will result in training and testing 
activities being conducted in NWTT Inland Waters only when necessitated 
by mission-essential training or testing program requirements, as it 
would impracticable to ``completely prohibit'' all activity in the 
area. Furthermore, the Navy will implement additional mitigation 
measures for activities that are conducted in the mitigation area, such 
as seasonal awareness messages, communication with sighting information 
networks, limitations on the type and location of active sonar and 
explosive activities, and a prohibition on live fire activities. For 
example, NMFS and the Navy have formalized existing informal procedures 
already conducted for Navy biologists to initiate communication with 
the appropriate marine mammal detection networks in NWTT Inland Waters 
prior to conducting explosive mine neutralization activities involving 
the use of Navy divers, Unmanned Underwater Vehicle Training, Civilian 
Port Defense--Homeland Security Anti-Terrorism/Force Protection 
Exercises, and Small Boat Attack Exercises. This mitigation has also 
been expanded to include a greater number of activities in the inland 
waters, and will help the Navy plan activities in a way that minimizes 
the potential for exposure of Southern Resident killer whales and gray 
whales. Further, with implementation of the new mitigation measures 
included in this final rule, we do not anticipate any take of Southern 
Resident killer whales in NWTT Inland Waters due to NWTT training and 
testing activities.
    Additionally, NMFS and the Navy have considered the impacts of Navy 
activities to all species in the development of mitigation areas, and 
the new mitigation in this area that reduces activity levels is likely 
to benefit other species such as humpback whales and gray whales. The 
commenter recommends ``noise isolation'' in relation to pierside 
training, but does not provide enough detail for NMFS to understand or 
address the issue. The mitigation as described in this final rule and 
the NWTT FSEIS/OEIS represents the maximum level of mitigation 
practical to implement, and any further mitigation in NWTT Inland 
Waters, such as mitigation for aircraft overflights, would be 
impracticable due to implications for safety, sustainability, and 
mission requirements for the reasons described in Chapter 5 
(Mitigation) and Appendix K (Geographic Mitigation Assessment) of the 
2020 NWTT FSEIS/OEIS. Further, NMFS does not anticipate, and has not 
authorized, take of marine mammals as a result of Growler or other 
overflights.
    Regarding the suggestion that NMFS ensure that Southern Resident 
killer whales will not be exposed to noise that can cause behavioral 
disruption before an activity proceeds, including by using the region's 
existing real-time hydrophone networks and by establishing additional 
hydrophone sites in key areas as needed, please see NMFS' response to 
Comment 45 regarding the use of hydrophone networks in real-time 
mitigation. While it is not possible for the Navy to avoid all 
behavioral disruption of Southern Resident killer whales while also 
effectively carrying out their mission, the measures NMFS is requiring 
will ensure the least practicable adverse impact on Southern Resident 
killer whales and other species and stocks.
    Potential vessel speed restrictions are addressed in the response 
to Comment 38. Please refer to that comment for our full response.
    Comment 34: A commenter recommended that NMFS require the Navy to 
expand its mitigation measures to more comprehensively protect gray 
whales in the Northern Puget Sound Gray Whale Mitigation Area between 
March and May. The commenter stated that the Navy should not conduct 
any testing or training activities within the Mitigation Area from 
March through May. The commenter recommended that, in addition, NMFS 
should require mitigation measures that limit vessel speeds to reduce 
the likelihood of vessel strike.
    Response: As described elsewhere in this Comments and Responses 
section, the Mitigation Areas section of this final rule and Section 
K.3.3 (Mitigation Areas for Marine Species in NWTT Inland Waters) of 
the 2020 NWTT FSEIS/OEIS discuss the enhanced mitigation measures in 
NWTT Inland Waters for gray whales as well as Southern Resident killer 
whales and other marine species. The Navy will implement additional 
geographic mitigation measures for activities that are conducted in the 
mitigation area, such as seasonal awareness messages for gray whales, 
limitations on the type and location of active sonar and explosive 
activities, and prohibition of live fire activities. The mitigation 
required from the Navy as described in this final rule and the 2020 
NWTT FSEIS/OEIS represents the maximum level of mitigation practicable. 
Any further mitigation in NWTT Inland Waters, including entirely 
prohibiting training or testing activities within the Northern Puget 
Sound Gray Whale Mitigation Area between March and May, is

[[Page 72342]]

impracticable due to implications for safety, sustainability, and 
mission requirements for the reasons described in Chapter 5 
(Mitigation) and Appendix K (Geographic Mitigation Assessment) of the 
2020 NWTT FSEIS/OEIS.
    Potential vessel speed restrictions are addressed in the response 
to Comment 38. Please refer to that comment for our full response.
    Comment 35: A commenter recommended that the Navy conduct no 
training or testing activities with mid-frequency sonar within the 
vicinity of Grays Canyon, Guide Canyon, Willapa Canyon, Astoria Canyon, 
and Eel Canyon at any time of year to provide protection for deep-
diving and/or noise-sensitive species, including endangered sperm 
whales and harbor porpoise. The commenter additionally recommended that 
the Navy observe the mitigation measures specified for the Marine 
Species Coastal Mitigation Area in these canyon areas, as appropriate.
    Response: NMFS and the Navy assessed the practicability of 
implementing the commenter's additional mitigation recommendations. As 
described in Section K.3.2.2.2 (Operational Assessment) of the 2020 
NWTT FSEIS/OEIS, training with active sonar in varying ocean floor 
topographies, such as near canyons, is essential to national security; 
therefore, additional restrictions on the use of active sonar near 
Quinault and in the vicinity of Grays, Guide, Willapa, Astoria, and Eel 
Canyons, are impracticable because such mitigation would preclude 
access to areas with the necessary environmental and oceanographic 
conditions that replicate military mission and combat conditions. 
Preventing access to critical training waterspace would have a 
significant impact on the ability of Navy units to meet their 
individual training and certification requirements (impacting the 
ability to deploy with the required level of readiness necessary to 
accomplish their missions), to certify forces to deploy to meet 
national security needs (limiting the flexibility of the Navy to 
project power, engage in multi-national operations, and conduct the 
full range of naval fighting capability in support of national security 
interests). NMFS concurs with the Navy's practicability assessment. 
While canyons can offer one form of valuable habitat for some species 
at certain times and a restriction on training and testing could 
potentially reduce the amount or severity of impacts to some degree for 
some species, given the protections offered by the procedural 
mitigation measures and the measures in other mitigation areas 
(including the measures added since the proposed rule), the high degree 
of impracticability described here supports the determination that this 
additional measure is not warranted, and therefore NMFS is not 
requiring the additional mitigation measures suggested by the 
commenter.
    Comment 36: A commenter stated that NMFS should expand activity 
restrictions within the proposed Marine Species Coastal Mitigation Area 
to the greatest extent practicable. The commenter stated that NMFS 
should prohibit or at least significantly limit the use of mid-
frequency active sonar from all sources, including dipping sonar (at 
least between December and June) within this Mitigation Area, at least 
out to the 200-meter isobath or 47 miles from shore; and, similarly, 
should further limit other activities, such as mine countermeasures and 
gunnery activities, that have the potential to result in species take. 
The commenter noted that the waters of greatest concern within the 
Mitigation Area extend between Cape Flattery, Washington, and Tillamook 
Head, Oregon, including the waters offshore of the Columbia River 
mouth, as these waters experience the highest relative habitat use for 
Southern Resident killer whales as indicated by presently available 
satellite telemetry data. These additional mitigation measures would 
also benefit other at-risk species, including the Central America and 
Mexico Distinct Population Segments of humpback whale.
    Another commenter stated that NMFS should include temporal 
restrictions based on Southern Resident killer whale activity and to 
reflect the best available location data of marine mammals. The 
commenter stated that specifically, NMFS should consider limitations on 
the Navy's activities in the Marine Species Coastal Mitigation Area, 
which covers winter habitat areas for Southern Resident killer whales. 
The commenter stated that NMFS should limit naval activities, which 
have the capacity to harm Southern Resident killer whales, especially 
mid-frequency sonar, over the winter months in order to limit harm to 
this endangered species.
    Response: This final rule includes extensive mitigation in the 
Marine Species Coastal Mitigation Area, including additional mitigation 
added since publication of the proposed rule. This final rule includes 
a new mitigation measure in this area which requires the Navy to issue 
seasonal awareness notification messages to alert Navy ships and 
aircraft operating within the mitigation area to the possible presence 
of increased concentrations of Southern Resident killer whales from 
December 1 to June 30, humpback whales from May 1 through December 31, 
and gray whales from May 1 to November 30. To assist in avoiding 
interactions with whales, the Navy will instruct vessels to remain 
vigilant to the presence of Southern Resident killer whales, humpback 
whales, and gray whales that may be vulnerable to vessel strikes or 
potential impacts from training and testing activities. Platforms will 
use the information from the awareness notification messages to assist 
their visual observation of applicable mitigation zones during training 
and testing activities and to aid in the implementation of procedural 
mitigation. Additionally, as included in the proposed rule, the Navy 
will conduct a maximum of 32 hours of surface ship hull-mounted MF1 
mid-frequency active sonar during training annually in the Olympic 
Coast National Marine Sanctuary Mitigation Area, which overlaps with 
the Marine Species Coastal Mitigation Area. The Navy will also 
implement annual restrictions on surface ship hull-mounted MF1 mid-
frequency active sonar (no more than 33 hours total) during testing in 
three mitigation areas combined: The Marine Species Coastal Mitigation 
Area within 20 nmi from shore, the new Juan de Fuca Eddy Marine Species 
Mitigation Area, and the Olympic Coast National Marine Sanctuary 
Mitigation Area. The annual restriction for testing previously only 
applied to the Olympic Coast National Marine Sanctuary Mitigation Area. 
This final rule also removes an exception that excluded the Quinault 
Range Site from the annual sonar restrictions that was included in the 
proposed rule. Now, the annual restrictions will apply throughout the 
entire Olympic Coastal National Marine Sanctuary Mitigation Area, 
including within the portion of the mitigation area that overlaps the 
Quinault Range Site. This reduction in activities is in areas that are 
important for Southern Resident killer whale and humpback whale feeding 
and migration. The Navy does not generally schedule training and 
testing near Cape Flattery due to the high volume of commercial vessel 
traffic in that portion of the Study Area. Additional mitigation that 
was added since the proposed rule is discussed in the Mitigation 
Measures section. This new mitigation includes a new mitigation area, 
the Juan de Fuca Eddy Mitigation Area, which encompasses waters near 
Cape Flattery as the commenter recommended.
    This final rule includes required procedural mitigation which is 
expected

[[Page 72343]]

to avoid or reduce potential impacts from active sonar on marine 
mammals wherever and whenever activities occur in the Study Area. 
Additionally, new procedural mitigation measures require the Navy to 
conduct Mine Countermeasure and Neutralization during daylight hours 
and in Beaufort sea state conditions of 3 or less, both of which 
increase the probability of marine mammal detection and, thereby, 
mitigation effectiveness. The Navy will also implement seasonal 
restrictions and distance-from-shore requirements for certain explosive 
bins, as described in detail in the Mitigation Areas section of this 
final rule. Additionally, the Navy will implement new annual and seven-
year explosive ordnance limitations specific to explosive mine 
countermeasure and neutralization testing. These restrictions and 
limitations will further reduce impacts to marine mammals from 
explosives in nearshore and offshore habitats, including important 
feeding and migration areas for Southern Resident killer whales and 
humpback whales.
    Additional geographic mitigation for active sonar beyond what is 
detailed in the Mitigation Areas section of this final rule, and in 
Section K.3 (Mitigation Areas to be Implemented) of the 2020 NWTT 
FSEIS/OEIS, would be impractical to implement for the reasons described 
in Appendix K (Geographic Mitigation Assessment) and Section 5.5.1 
(Active Sonar) of the 2020 NWTT FSEIS/OEIS. NMFS has carefully reviewed 
this information and determined that additional mitigation measures 
would be impracticable.
    The potential restriction of dipping sonar is discussed in the 
response to Comment 52. See that comment for our full response.
    Comment 37: Commenters stated that additional mitigation measures 
are necessary and must be required, specifically additional mitigation 
and monitoring in Southern Resident killer whale offshore habitat. A 
commenter stated that this is necessary given the potential increased 
use of this area and the unique activities--such as active sonar--that 
take place in this portion of the NWTT range. A commenter stated that 
it is even more critical now that the offshore density numbers have 
been updated and have dramatically increased the anticipated incidents 
of level B harassment affecting Southern Resident killer whales. 
Approximately 92 percent of training impacts and 68 percent of testing 
impacts on killer whales are projected to occur in the offshore area.
    Response: This final rule includes extensive mitigation designed to 
reduce impacts to Southern Resident killer whales, including mitigation 
in their offshore habitat, and new mitigation in this habitat since 
publication of the proposed rule. The Marine Species Coastal Mitigation 
Area, the Juan de Fuca Eddy Marine Species Mitigation Area, and the 
Olympic Coast National Marine Sanctuary Mitigation Area contain 
mitigation measures expected to reduce impacts to Southern Resident 
killer whales in their offshore habitat. Since the proposed rule, new 
mitigation measures have been added pertaining to the NWTT Offshore 
Area. One new measure requires the Navy to implement annual 
restrictions on surface ship hull-mounted MF1 mid-frequency active 
sonar (no more than 33 hours total) in three mitigation areas combined: 
Within 20 nmi from shore in the Marine Species Coastal Mitigation Area, 
in the new Juan de Fuca Eddy Marine Species Mitigation Area, and in the 
Olympic Coast National Marine Sanctuary Mitigation Area. The annual 
restriction for testing previously only applied to the Olympic Coast 
National Marine Sanctuary Mitigation Area. This final rule also removes 
an exception that excluded the Quinault Range Site from the annual 
sonar restrictions that was included in the proposed rule. Now, the 
annual restrictions will apply throughout the entire Olympic Coastal 
National Marine Sanctuary Mitigation Area, including within the portion 
of the mitigation area that overlaps the Quinault Range Site. This 
reduction in activities is in areas that are important for Southern 
Resident killer whale and humpback whale feeding and migration. 
Additionally, the Navy will issue seasonal awareness notification 
messages within 50 nmi from shore to alert Navy ships and aircraft 
operating within the Marine Species Coastal Mitigation Area to the 
possible presence of increased concentrations of Southern Resident 
killer whales from December 1 to June 30, humpback whales from May 1 
through December 31, and gray whales from May 1 to November 30. To 
assist in avoiding interactions with whales, the Navy will instruct 
vessels to remain vigilant to the presence of Southern Resident killer 
whales, humpback whales, and gray whales that may be vulnerable to 
vessel strikes or potential impacts from training and testing 
activities. Platforms will use the information from the awareness 
notification messages to assist their visual observation of applicable 
mitigation zones during training and testing activities and to aid in 
the implementation of procedural mitigation. Please refer to the 
Mitigation Areas section of this final rule for additional information 
on the mitigation measures in the NWTT offshore waters.

Other Mitigation and Monitoring

    Comment 38: A commenter stated that the proposed rule does not 
contain any indication that a practicability analysis was conducted, 
nor does it prescribe any speed reduction measure. The commenter states 
that this failure appears based on an unsupported finding that vessel 
noise generated by Navy vessels has de minimis or no impacts on 
Southern Resident killer whales and other marine mammals. Commenters 
recommended that NMFS require the Navy to engage in lowest practicable 
speed reductions in biologically important habitats to reduce noise, 
including in designated critical habitat for endangered Southern 
Resident killer whales and other biologically important habitat for 
vulnerable species. A commenter also stated that Washington State 
increased vessel regulations in 2019 to reduce noise and disturbance to 
Southern Resident killer whales from small vessels, including by 
enacting a 7-knot speed limit within half a nautical mile of the killer 
whales. The commenter also referenced the Vancouver Fraser Port 
Authority's Enhancing Cetacean Habitat and Observation (ECHO) Program 
which operates a voluntary slowdown of large ships transiting Southern 
Resident killer whale habitat and a lateral displacement trial to shift 
vessels away from high-use areas. The commenter recommended that the 
Navy implement similar measures for transiting vessels within the 
Salish Sea to reduce noise and disturbance in inland waters. 
Additionally, given that the speed of Navy ships during all aspects of 
their operations potentially impact marine mammals, the commenter 
recommended that NMFS require the Navy to collect and report data on 
ship speed as part of the rulemaking process. The commenter asserts 
that this will allow for objective evaluation by NMFS of ship-strike 
risk, of harassment resulting from vessel activity, and of the 
potential benefit of additional speed-focused mitigation measures. 
Finally, a commenter asserts that NMFS should require the Navy to take 
steps to quiet smaller support vessels used in the NWTT Study Area, by 
seeking and incorporating best commercial off-the-shelf technology for 
vessel retrofits and new builds.
    Response: Generally speaking, it is impracticable (because of 
impacts to mission effectiveness) to further reduce ship speeds for 
Navy activities, and, moreover, given the maneuverability of

[[Page 72344]]

Navy ships at higher speeds and the presence of effective Lookouts, any 
further reduction in speed would be unlikely to reduce the already low 
probability of a ship strike. Navy ships generally operate at speeds in 
the range of 10-15 knots, and submarines generally operate at speeds in 
the range of 8-13 knots. Small craft (for purposes of this discussion, 
less than 40 ft), which are all support craft, have more variable 
speeds dependent on the mission. While these speeds are representative 
of most events, some vessels need to operate outside of these 
parameters under certain training and testing scenarios. The Navy is 
unable to impose a 7-knot ship speed limit because it would not be 
practical to implement and would impact the effectiveness of the Navy's 
activities by putting constraints on training, testing, and scheduling. 
The Navy requires flexibility in use of variable ship speeds for 
training, testing, operational, safety, and engineering qualification 
requirements. Navy ships typically use the lowest speed practical given 
individual mission needs. NMFS has reviewed the analysis of these 
additional suggested restrictions and the impacts they would have on 
military readiness and concurs with the Navy's assessment that they are 
impracticable (see section 5.3.4.1 Vessel Movement and section 5.5 
Measures Considered but Eliminated in the 2020 NWTT FSEIS/OEIS). 
Therefore, the Navy is already planning to engage in the lowest 
practicable speed in biologically important habitats, including in 
designated critical habitat for endangered Southern Resident killer 
whales and other biologically important habitat for vulnerable species, 
as well as in all other areas.
    The main driver for ship speed reduction is reducing the 
possibility and severity of ship strikes to large whales. However, even 
given the wide ranges of speeds from slow to fast that Navy ships must 
use to meet training and testing requirements, the Navy has a very low 
strike history to large whales in the NWTT Study Area. As further 
discussed in the Estimated Take from Vessel Strikes by Serious Injury 
or Mortality section, Navy vessel strike records have been kept since 
1995, and since 1995 there have been two recorded strikes of whales by 
Navy vessels (or vessels being operated on behalf of the Navy) in the 
NWTT Study Area, one in 2012, and one in 2016. Neither strike was 
associated with training or testing activities.
    As discussed in the 2015 NWTT FEIS/OEIS Section 5.1.2 (Vessel 
Safety), Navy standard operating procedures require that ships operated 
by or for the Navy have personnel assigned to stand watch at all times, 
day and night, when moving through the water (i.e., when the vessel is 
underway). A primary duty of watch personnel is to ensure safety of the 
ship, which includes the requirement to detect and report all objects 
and disturbances sighted in the water that may be indicative of a 
threat to the ship and its crew, such as debris, a periscope, surfaced 
submarine, or surface disturbance. Per safety requirements, watch 
personnel also report any marine mammals sighted that have the 
potential to be in the direct path of the ship, as a standard collision 
avoidance procedure. As described in Section 5.3.4.1 (Vessel Movement) 
of the 2020 NWTT FSEIS/OEIS, Navy vessels are also required to operate 
in accordance with applicable navigation rules. Applicable rules 
include the Inland Navigation Rules (33 CFR part 83) and International 
Regulations for Preventing Collisions at Sea (72 Collision 
Regulations), which were formalized in the Convention on the 
International Regulations for Preventing Collisions at Sea, 1972. These 
rules require that vessels proceed at a safe speed so proper and 
effective action can be taken to avoid collision and so vessels can be 
stopped within a distance appropriate to the prevailing circumstances 
and conditions. In addition to standard operating procedures, the Navy 
implements mitigation to avoid vessel strikes, which includes requiring 
vessels to maneuver to maintain at least 500 yd away from whales, and 
200 yd or 100 yd away from other marine mammals (depending on the size 
of the vessel). Additionally, please see the Estimated Take from Vessel 
Strikes by Serious Injury or Mortality section of this rule and section 
3.4.2.4.1 of the 2020 NWTT FSEIS/OEIS for discussion regarding the 
differences between Navy ships and commercial ships which make Navy 
ships less likely to affect marine mammals.
    When developing Phase III mitigation measures, the Navy analyzed 
the potential for implementing additional types of mitigation, such as 
vessel speed restrictions within the NWTT Study Area. The Navy 
determined that based on how the training and testing activities will 
be conducted within the NWTT Study Area, vessel speed restrictions 
would be incompatible with practicability criteria for safety, 
sustainability, and training and testing missions, as described in 
Chapter 5 (Mitigation), Section 5.3.4.1 (Vessel Movement) of the 2020 
NWTT FSEIS/OEIS.
    Regarding reporting of ship speed, as required through the Navy's 
Notification and Reporting Plan (Vessel Strike section), Navy vessels 
are required to report extensive information, including ship speed, 
pursuant to any marine mammal vessel strikes. Therefore, the data 
required for ship strike analysis discussed in the comment is already 
being collected. Any additional data collection requirement would 
create an unnecessary burden on the Navy. Regarding vessel noise from 
Navy ships, Navy vessels are intentionally designed to be quieter than 
civilian vessels, and given that adverse impacts from vessel noise are 
not anticipated to result from Navy activities (see the Potential 
Effects of Specified Activities on Marine Mammals and Their Habitat 
section in the proposed rule), there is no anticipated harassment 
caused by vessel activity and therefore no need to collect and report 
data on ship speed for this purpose.
    Regarding quieting small support vessels, most of the Navy's 
vessels already have state of the art quieting technologies employed to 
reduce their sound profile to assist them in avoiding detection by 
enemy forces, therefore, they are much quieter than commercial/
recreational vessels of similar sizes.
    Comment 39: A commenter stated that NMFS does not incorporate 
stand-off distances of any size within its requirements for the 
proposed mitigation areas, providing only that activities not take 
place ``within'' the defined areas. Thus, activities that are otherwise 
restricted or limited within a mitigation area could occur directly 
along the boundary and ensonify the area at levels capable of causing 
injury or increasing the risk or severity of behavioral disruption. The 
commenter asserts that stand-off distances are a reasonable mitigation 
measure that is routinely required by NMFS in authorizing take under 
the MMPA. The commenter recommended that NMFS consider establishing 
stand-off distances around its mitigation areas to the greatest extent 
practicable, allowing for variability in size given the location of the 
mitigation area, the type of operation at issue, and the species of 
concern.
    Response: The mitigation areas included in the final rule and 
described in Appendix K (Geographic Mitigation Assessment) of the 2020 
NWTT FSEIS/OEIS represent the maximum mitigation within mitigation 
areas and the maximum size of mitigation areas that are practicable for 
the Navy to implement under their specified activity. Implementing 
additional mitigation (e.g., stand-off distances that

[[Page 72345]]

would extend the size of the mitigation areas) beyond what is included 
in the final rule is impracticable due to implications for safety, 
sustainability, and the Navy's ability to continue meeting its mission 
requirements. For example, as described in Section K.3.2.2.2 
(Operational Assessment) of the 2020 NWTT FSEIS/OEIS, creating stand-
off distances from the 12 nmi, 20 nmi, and 50 nmi limits within the 
Marine Species Coastal Mitigation Area would result in activities being 
conducted farther offshore. Moving activities farther offshore would be 
impractical due to decreased event realism, increased resource 
allocations and operational costs (due to extending the distance 
offshore and proximity to Navy support facilities, which would increase 
fuel consumption, maintenance, and time on station), increased safety 
risks (associated with conducting training and testing at extended 
distances offshore and farther away from critical medical and search 
and rescue resources), and accelerated fatigue-life of aircraft and 
ships (leading to increased safety risk and higher maintenance costs). 
Increased resource allocations and operational costs would serve as a 
limiting factor for Navy surface vessels whose available underway times 
are constrained by available manpower and fuel expenses. This would 
also reduce training or testing opportunities during a platform's 
limited available timeframes because increased time spent transiting to 
more distant training areas or test sites results in decreased time 
available for training or testing.
    When practicable, NMFS sometimes recommends the inclusion of 
buffers around areas specifically delineated to contain certain 
important habitat or high densities of certain species, to allow for 
further reduced effects on specifically identified features/species. 
However, buffers are not typically considered necessary or appropriate 
in combination with more generalized and inclusive measures, such as 
coastal offsets or other areas that are intended to broadly contain 
important features for a multitude of species. In the case of this 
rulemaking, NMFS and the Navy have included an extensive array of broad 
protective areas that will reduce impacts on numerous species and 
habitats (including additions to what was described in the proposed 
rule) and, as described above, limitations in additional areas is not 
practicable.
    Comment 40: A commenter noted that as with the consent order 
entered by the court in the Conservation Council case, the present 
proposed rule would allow the Navy to derogate from the measures 
associated with the mitigation areas where necessary for national 
security, if certain conditions are met. Specifically, authorization 
must be granted, the Navy must provide NMFS with advance notice of the 
derogation and with further information after the completion of events, 
and the Navy must provide information on those activities in its annual 
reports. Unlike the consent order, however, the proposed rule does not 
clearly restrict derogation authority to highest-level officers.
    Under the consent order, authority could be invoked only by certain 
named officers representing the highest command authority, namely the 
Commander or Acting Commander of the Pacific Fleet, for training 
activities, and the Commander or Acting Commander of the various 
research branches for testing activities, and then only when the Navy 
``deems it necessary for national defense.'' Similarly, at least some 
of the geographic areas adopted by the Navy in prior NEPA processes, 
such as the Humpback Whale Cautionary Area established in previous 
Hawaii-Southern California Training and Testing EISs, allowed for 
derogation only upon approval of the Pacific Fleet Commander. This 
requirement made it more likely that derogation decisions would be 
taken with the greatest seriousness and consideration. By contrast, the 
proposed rule is unclear in its designation, generally allowing units 
to obtain permission from ``the appropriate designated Command 
authority.'' NMFS should clarify that authorization may be given only 
by the highest-level Command authorities, consistent with the consent 
order in Conservation Council.
    Response: The commenter references the terms of a 2015 settlement 
agreement approved by a court for a previous MMPA rulemaking for Navy 
activities in a different study area, none of which is applicable to 
the Navy's planned activities in this study area. In addition, as 
discussed in the response to Comment 28, the terms that were agreed to 
in that settlement agreement were never evaluated based on the best 
available science and under the two prongs that NMFS (and the Navy) 
apply to evaluate potential measures under the ``least practicable 
adverse impact'' standard.
    For this rulemaking, NMFS along with the Navy considered the 
current conditions specific to the Navy's planned activities for the 
NWTT Study Area, the needs of the species and stocks along with their 
habitat, and the practicability of potential measures. As the commenter 
notes, for several of the measures in geographic mitigation areas the 
Navy may conduct an otherwise prohibited activity if necessary for 
national security, but only if Navy personnel have obtained permission 
from the appropriate designated Command authority prior to commencing 
the activity, provide NMFS with advance notification, and include 
information about the event in the annual activity reports to NMFS. It 
is not necessary to require permission from the highest-level Command 
authority to ensure that a valid national security need exists or that 
all other requirements of the provision will be complied with. The 
commenter has provided no information to indicate that the slightly 
different phrasing of the condition or that the differences in the 
level of Navy approval will lead to misapplication of the provision.
    Comment 41: A commenter recommended that NMFS consider additional 
measures to address mitigation for explosive events at night and during 
periods of low-visibility, either by enhancing the observation 
platforms to include aerial and/or passive acoustic monitoring (such as 
glider use), as has been done here with sinking exercises, or by 
restricting events to particular Beaufort sea states (depending on 
likely species presence and practicability).
    Response: This final rule includes new mitigation that requires the 
Navy to conduct explosive mine countermeasure and neutralization 
testing activities in daylight hours only and in Beaufort Sea state 
number 3 conditions or less. The Navy will also continue to implement 
mitigation that requires explosive mine neutralization training 
activities involving Navy divers to be conducted in Beaufort Sea state 
number 2 conditions or less and not in low visibility conditions. As 
described in Section 5.5.2 (Explosives) of the 2020 NWTT FSEIS/OEIS, 
when assessing and developing mitigation, NMFS and the Navy considered 
further restrictions on the use of explosives (e.g., during periods of 
low visibility or in certain sea state conditions). The locations and 
timing of the training and testing activities that use explosives vary 
throughout the NWTT Study Area based on range scheduling, mission 
requirements, testing program requirements, and standard operating 
procedures for safety and mission success. Although activities using 
explosives typically occur during the daytime for safety reasons, it is 
impracticable for the Navy to prohibit every type of explosive activity 
at night or during low visibility conditions or during different 
Beaufort Sea states.

[[Page 72346]]

Doing so would diminish activity realism, which would impede the 
ability for Navy personnel to train and become proficient in using 
explosive weapons systems (which would result in a significant risk to 
personnel safety during military missions and combat operations), and 
would impede the Navy's ability to certify forces to deploy to meet 
national security needs.
    Passive acoustic devices, whether vessel-deployed or using research 
sensors on gliders or other devices, can serve as queuing information 
that vocalizing marine mammals could be in the vicinity. Passive 
acoustic detection does not account for individuals not vocalizing. 
Navy surface ships train to localize submarines, not marine mammals. 
Some aviation assets deploying ordnance do not have concurrent passive 
acoustic sensors. Furthermore, Navy funded civilian passive acoustic 
sensors do not report in real-time. Instead, a glider is set on a 
certain path or floating/bottom-mounted sensor deployed. The sensor has 
to then be retrieved often many months after deployment (1-8 months), 
data is sent back to the laboratory, and then subsequently analyzed. 
Combined with lack of localization, gliders with passive acoustic 
sensors are therefore not suitable for mitigation.
    The Navy does employ passive acoustic monitoring when practicable 
to do so (i.e., when assets that have passive acoustic monitoring 
capabilities are already participating in the activity) and several of 
the procedural mitigation measures reflect this, but many platforms do 
not have passive acoustic monitoring capabilities. Adding a passive 
acoustic monitoring capability (either by adding a passive acoustic 
monitoring device (e.g., hydrophone) to a platform already 
participating in the activity, or by adding a platform with integrated 
passive acoustic monitoring capabilities to the activity, such as a 
sonobuoy) for mitigation is not practicable. As discussed in Section 
5.5.3 (Active and Passive Acoustic Monitoring Devices) of the 2020 NWTT 
FSEIS/OEIS, there are significant manpower and logistical constraints 
that make constructing and maintaining additional passive acoustic 
monitoring systems or platforms for each training and testing activity 
impracticable. The Navy is required to implement pre-event observation 
mitigation, as well as post-event observation when practical, for all 
in-water explosive events. If there are other platforms participating 
in these events and in the vicinity of the detonation area, they will 
also visually observe this area as part of the mitigation team.
    The Mitigation Section (Chapter 5) of the 2020 NWTT FSEIS/OEIS 
includes a full discussion of the mitigation measures that the Navy 
will implement, as well as those that have been considered but 
eliminated, including potential measures that have been raised by NMFS 
or the public in the past. The Navy has explained that training and 
testing in both good visibility (e.g., daylight, favorable weather 
conditions) and low visibility (e.g., nighttime, inclement weather 
conditions) is vital because environmental differences between day and 
night and varying weather conditions affect sound propagation and the 
detection capabilities of sonar. Temperature layers that move up and 
down in the water column and ambient noise levels can vary 
significantly between night and day. This affects sound propagation and 
could affect how sonar systems function and are operated. While some 
small reduction in the probability or severity of impacts could result 
from the implementation of this measure, it would not be practicable 
for the Navy to restrict operations in low visibility and the measure 
is not, therefore, warranted.
    Comment 42: A commenter recommended that sonar signals might be 
modified to reduce the level of impact at the source. Mitigating active 
sonar impacts might be achieved by employing down-sweeps with harmonics 
or by reducing the level of side bands (or harmonics). The commenter 
recommended that more research of this nature be carried out in order 
to understand the extent to which these results can be generalized 
across species. The commenter also recommended that the feasibility of 
implementing signal modifications (such as those recommended above) 
into Navy operations be explored.
    Response: The commenter notes that NOAA's Ocean Noise Strategy 
Roadmap puts an emphasis on source modification and habitat 
modification as an important means for reducing impacts. However, where 
the modification of sources is discussed, the focus of the Roadmap is 
on modifying technologies for activities in which low frequency, 
broadband sound (which contributes far more significantly to increased 
chronic noise levels) is incidental to the activity (e.g., maritime 
traffic). As described in the 2020 NWTT FSEIS/OEIS, at this time, the 
science on the differences in potential impacts of up or down sweeps of 
the sonar signal (e.g., different behavioral reactions) is extremely 
limited and requires further development before a determination of 
potential mitigation effectiveness can be made. There is data on 
behavioral responses of a few captive harbor porpoises to varying 
signals. Although this very limited data set suggests that up or down 
sweeps of the sonar signal may result in different reactions by harbor 
porpoises in certain circumstances, the author of those studies 
highlights the fact that different species respond to signals with 
varying characteristics in a number of ways. In fact, the same signals 
cited here were also played to harbor seals, and their responses were 
different from the harbor porpoises. Furthermore, harmonics in a signal 
result from a high-intensity signal being detected in close proximity; 
they could be artificially removed for a captive study, but cannot be 
whitened in the open ocean. Active sonar signals are designed 
explicitly to provide optimum performance at detecting underwater 
objects (e.g., submarines) in a variety of acoustic environments. If 
future studies indicate that modifying active sonar signals could be an 
effective mitigation approach, then NMFS with the Navy will investigate 
if and how the mitigation would affect the sonar's performance and how 
that mitigation may be applied in future authorizations, but currently 
NMFS does not have a set timeline for this research and how it may be 
applied to future rulemakings.
    Comment 43: A commenter stated that while the Navy rejects 
modifying sonar sound sources as a mitigation measure, a decision that 
was summarily upheld by NMFS during its most recent proposed rule for 
Navy activities off Southern California and Hawaii, the Navy never 
explains why making the modifications implied by the marine mammal 
behavioral studies discussed Kastelein et al. (2012, 2014, 2015), 
G[ouml]tz, T., and Janik (2011), and Hastie et al. (2014) would be 
impracticable. The commenter asserts that some of these modifications, 
such as converting up-sweeps to down-sweeps, would not alter the 
system's spectral output in any way. The commenter believes source 
modification requires greater validation across species and in more 
behavioral contexts before any decisions are made to alter signals, but 
given the preliminary data, and given the potential of this measure to 
reduce the instances and severity of behavioral harassment, the 
commenter recommended that NMFS require the Navy to expedite that 
research and set a timeline for this research within the context of the 
present rulemaking. The commenter asserted that the Navy's ongoing 
research off Southern California presents a strong opportunity for 
advancing mitigation research in this

[[Page 72347]]

area. The Navy's multi-year Southern California behavioral response 
studies provide baseline data and a vehicle for testing the effects of 
sonar modifications in the field. Research on modified signals can be 
incorporated into those ongoing behavioral response studies as a 
variant on exposure experiments on tagged animals, for which there 
already exists data on blue whales, fin whales, Cuvier's beaked whales, 
and other species.
    Response: The Navy has explained that it explicitly designs its 
active sonar signals to provide optimum performance at detecting 
underwater objects (e.g., submarines) in a variety of acoustic 
environments. The Navy assessed the potential for implementing active 
sonar signal modification as mitigation. At this time, the science on 
the differences in potential impacts of up or down sweeps of the sonar 
signal (e.g., different behavioral reactions) is extremely limited and 
as noted by the commenter requires further development. For example, 
Kastelein et al. (2012) researched the behavioral responses of a single 
captive harbor porpoise to varying sonar signals. Although this very 
limited data set suggests up or down sweeps of the sonar signal may 
result in different reactions by harbor porpoises in certain 
circumstances, this science requires further development (e.g., to 
determine potential reactions by other individual harbor porpoises and 
other marine mammal species). If future studies indicate that modifying 
active sonar signals (i.e., up or down sweeps) could be an effective 
mitigation approach, then the Navy will investigate if and how the 
mitigation would affect the sonar's performance. As required by this 
final rule, the Navy will continue to implement robust monitoring and 
adaptive management, and NMFS and the Navy will consider the 
recommendations of the commenter, along with other needs, when 
developing and prioritizing future research and monitoring studies for 
the NWTT Study Area.
    Comment 44: A commenter recommended that NMFS should consider 
requiring compensatory mitigation for the adverse impacts of the 
permitted activity on marine mammals and their habitat that cannot be 
prevented or mitigated.
    Response: Compensatory mitigation is not required under the MMPA. 
Instead, authorizations must include means of effecting the least 
practicable adverse impact from the activities on the affected species 
or stocks and their habitat, which this rule has done through the 
required procedural and geographic area mitigation measures. Also, the 
commenter did not recommend any specific measures, rendering it 
impossible to consider its recommendation at a broader level.
    Comment 45: A commenter stated that the mitigation zones required 
to mitigate the impact of the Navy's testing and training activities 
are based purely on animal sightings by vessel board Lookouts, and 
should any animals be underwater they could be easily missed.
    Several commenters suggested that the Navy could use information 
from real-time whale alert systems, including NOAA's hydrophone network 
and data from the Whale Report Alert System (WRAS) used by the 
Washington State Ferries and other maritime professionals. A commenter 
stated that these additional, often-superior local sources of such 
time-sensitive information can help identify acoustically silent whales 
that have been sighted elsewhere that could be moving into training or 
testing areas. Another commenter stated that NMFS does not evaluate the 
possibility of using this data from either an effectiveness or 
practicability standpoint. Another commenter stated that this measure 
is indisputably both available and practical, per the factors that NMFS 
considers in its evaluation.
    A commenter stated that this data is readily available and serves 
as a useful resource for the Navy to plan out its testing and training 
activities to reduce impacts to marine mammals. The commenter stated 
that in fact, it could even increase the effectiveness of the Navy's 
testing and training activities if it helps to reduce the number of 
delayed or canceled actions due to animal presence. The commenter 
recommended that NMFS amend its proposed authorization to require the 
Navy to utilize readily available whale location data as a form of 
mitigation.
    A commenter stated that for mitigation for active sonar training 
and testing activities in Puget Sound, NMFS should require the Navy to 
consult regional real-time whale alert systems rather than relying 
solely on human observers on Navy vessels and communications with NMFS.
    Response: NMFS acknowledges the fact that some animals in the 
mitigation zone could go unobserved by the Lookouts. We have taken that 
into consideration in the quantitative evaluation of mitigation 
effectiveness, and that is why some take by Level A harassment is 
authorized.
    This final rule includes formalization of existing informal 
mitigation procedures already conducted by Navy biologists to initiate 
communication with the appropriate marine mammal detection networks in 
NWTT Inland Waters prior to conducting (1) explosive mine 
neutralization activities involving the use of Navy divers, (2) 
Unmanned Underwater Vehicle Training at four locations, (3) Civilian 
Port Defense--Homeland Security Anti-Terrorism/Force Protection 
Exercises, and (4) Small Boat Attack Exercises. This mitigation, which 
would increase real-time awareness of nearby cetaceans, increase the 
likelihood of detection, and enhance the success of procedural 
mitigations, has also been expanded to include a greater number of 
activities in the inland waters, and will help the Navy plan activities 
in a way that minimizes the potential for exposure of Southern Resident 
killer whales and gray whales, as described in the Mitigation Measures 
section of the rule and Section K.3.3 (Mitigation Areas for Marine 
Species in NWTT Inland Waters) of the 2020 NWTT FSEIS/OEIS.
    The Navy also uses passive acoustic monitoring technology for some 
exercises. NMFS and the Navy considered the use of passive acoustic 
monitoring during additional exercises, but determined that it is not 
practicable. Please refer to Comment 47 for additional information 
about the implementation of passive acoustic monitoring.
    NMFS is unaware of a hydrophone network, aside from some 
hydrophones NOAA has deployed for individual projects such as to 
research Southern Resident killer whales in offshore waters, a single 
noise reference station offshore the Strait of Juan de Fuca, and two to 
three assets in Olympic Coast National Marine Sanctuary. However, all 
of these hydrophone systems are bottom mounted passive acoustic 
monitoring devices with no real-time reporting capability, and 
therefore they cannot be used for real time assessment. There are other 
hydrophones deployed in NWTT Inland Waters by private individuals or 
entities (i.e. NGOs), but data availability and issues with the Navy 
accessing external sites remains an issue. The Navy will also continue 
to assess the practicality of other available monitoring techniques as 
technologies advance.
    Additionally, a Navy team began participating in the Governor of 
Washington's Southern Resident Orca Task Force in 2019, including the 
Vessels Working Group. As part of the Vessels Working Group, the Navy 
began investigating potential mechanisms for broadcasting WRAS 
sightings of Southern Resident killer whales to Navy platforms 
conducting training or testing in the Inland Waters. The Navy has met

[[Page 72348]]

with the program developers of the WRAS to begin exploring potential 
applications for Navy use, considering factors such as the geographic 
extent of sighting reports as well as the Navy's stringent information 
security requirements (e.g., associated with broadcasting unit location 
using an unsecured application). As the WRAS continues to expand into 
U.S. waters, NMFS and the Navy will continue to explore the opportunity 
to engage with this sightings network as a future mitigation tool. Any 
potential adoption of the system will be coordinated through the 
adaptive management provisions of this final rule.
    Comment 46: A commenter recommended that NMFS should consider 
requiring the Navy to employ thermal detection in optimal conditions, 
or, alternatively, require the establishment of a pilot program for 
thermal detection, with annual review under the adaptive management 
system. According to the 2019 NWTT DSEIS/OEIS, the Navy ``plans to 
continue researching thermal detection technology to determine their 
effectiveness and compatibility with Navy applications.''
    Response: Thermal detection systems are more useful for detecting 
marine mammals in some marine environments than others. Current 
technologies have limitations regarding water temperature and survey 
conditions (e.g., rain, fog, sea state, glare, ambient brightness), for 
which further effectiveness studies are required. Thermal detection 
systems are generally thought to be most effective in cold 
environments, which have a large temperature differential between an 
animal's temperature and the environment. In addition, current thermal 
detection systems have proven more effective at detecting large whale 
blows than the bodies of small animals, particularly at a distance. The 
effectiveness of current technologies has not been demonstrated for 
small marine mammals. Research to better understand, and improve, 
thermal technology continues, as mentioned in the 2019 NWTT DSEIS/OEIS 
and described below.
    The Navy has been investigating the use of thermal detection 
systems with automated marine mammal detection algorithms for future 
mitigation during training and testing, including on autonomous 
platforms. For example, the Defense Advanced Research Projects Agency 
funded six initial studies to test and evaluate infrared-based thermal 
detection technologies and algorithms to automatically detect marine 
mammals on an unmanned surface vehicle. Based on the outcome of these 
initial studies, the Navy is pursuing additional follow-on research 
efforts.
    Thermal detection technology being researched by the Navy, which is 
largely based on existing foreign military grade hardware, is designed 
to allow observers and eventually automated software to detect the 
difference in temperature between a surfaced marine mammal (i.e., the 
body or blow of a whale) and the environment (i.e., the water and air). 
Technologies are advancing but continue to be limited by their (1) 
reduced performance in certain environmental conditions, (2) ability to 
detect certain animal characteristics and behaviors, (3) low sensor 
resolution and narrow fields of view, and (4) high cost and low 
lifecycle (Boebel, 2017; Zitterbart et al., 2013).
    Thermal detection systems for military applications are deployed on 
various Department of Defense (DoD) platforms. These systems were 
initially developed for night time targeting and object detection 
(e.g., a boat, vehicle, or people). Existing specialized DoD infrared/
thermal capabilities on Navy aircraft and surface ships are designed 
for fine-scale targeting. Viewing arcs of these thermal systems are 
narrow and focused on a target area. Furthermore, sensors are typically 
used only in select training events, not optimized for marine mammal 
detection, and have a limited lifespan before requiring expensive 
replacement. Some sensor elements can cost upward of $300,000 to 
$500,000 per device, so their use is predicated on a distinct military 
need.
    Thermal detection systems are currently used by some specialized 
U.S. Air Force aircraft for marine mammal mitigation. These systems are 
specifically designed for and integrated into Air Force aircraft and 
cannot be added to Navy aircraft.
    The effectiveness remains unknown in using certain DoD thermal 
systems for the detection of marine mammals without the addition of 
customized system-specific computer software to provide critical 
reliability (enhanced detection, cueing for an operator, reduced false 
positives, etc.).
    Current DoD thermal sensors are not always optimized for marine 
mammal detections versus object detection, nor do these systems have 
the automated marine mammal detection algorithms the Navy is testing 
via its ongoing research program. The combination of thermal technology 
and automated algorithms are still undergoing demonstration and 
validation under Navy funding.
    Thermal detection systems specifically for use in detecting marine 
mammals have been investigated by the Navy for more than a decade and 
are discussed in Section 5.5.4 of the 2020 NWTT FSEIS/OEIS. The 
effectiveness of even the most advanced thermal detection systems with 
technological designs specific to marine mammal surveys is highly 
dependent on environmental conditions, animal characteristics, and 
animal behaviors. At this time, thermal detection systems have not been 
proven to be more effective than, or equally effective as, traditional 
techniques currently employed by the Navy to observe for marine mammals 
(i.e., naked-eye scanning, hand-held binoculars, high-powered 
binoculars mounted on a ship deck). The use of thermal detection 
systems instead of traditional techniques would compromise the Navy's 
ability to observe for marine mammals within its mitigation zones in 
the range of environmental conditions found throughout the NWTT Study 
Area. Focusing on thermal detection systems could also provide a 
distraction from and compromise the Navy's ability to implement its 
established observation and mitigation requirements. The mitigation 
measures discussed in the Mitigation Measures section include the 
maximum number of Lookouts the Navy can assign to each activity based 
on available manpower and resources; therefore, it would be impractical 
to add personnel to serve as additional Lookouts. For example, the Navy 
does not have available manpower to add Lookouts to use thermal 
detection systems in tandem with existing Lookouts who are using 
traditional observation techniques. Furthermore, high false positive 
rates of thermal detection systems could result in the Navy 
implementing mitigation for features incorrectly identified as marine 
mammals. Increasing the instances of mitigation implementation based on 
incorrectly identified features would have significant impacts on the 
ability for training and testing activities to accomplish their 
intended objectives, without providing any mitigation benefit to the 
species.
    The Defense Advanced Research Projects Agency funded six initial 
studies to test and evaluate infrared-based thermal detection 
technologies and algorithms to automatically detect marine mammals on 
an unmanned surface vehicle. Based on the outcome of these initial 
studies, the Navy is pursuing additional follow-on research efforts. 
Additional studies are currently being planned for 2020+ but additional 
information on the exact timing and scope of these studies is not 
currently

[[Page 72349]]

available (still in the development stage).
    The Office of Naval Research Marine Mammals and Biology program 
also funded a project (2018) to test the thermal limits of infrared-
based automatic whale detection technology. That project focused on 
capturing whale spouts at two different locations featuring subtropical 
and tropical water temperatures, optimizing detector/classifier 
performance on the collected data, and testing system performance by 
comparing system detections with concurrent visual observations. 
Results indicated that thermal detection systems in subtropical and 
tropical waters can be a valuable addition to marine mammal surveys 
within a certain distance from the observation platform (e.g., during 
seismic surveys, vessel movements), but have challenges associated with 
false positive detections of waves and birds (Boebel, 2017). While 
Zitterbart et al. (2020) reported on the results of land-based thermal 
imaging of passing whales, their conclusion was that thermal technology 
under the right conditions and from land can detect a whale within 3 km 
although there could also be lots of false positives, especially if 
there are birds, boats, and breaking waves at sea. Thermal detection 
systems exhibit varying degrees of false positive detections (i.e., 
incorrect notifications) due in part to their low sensor resolution and 
reduced performance in certain environmental conditions. False positive 
detections may incorrectly identify other features (e.g., birds, waves, 
boats) as marine mammals. In one study, a false positive rate 
approaching one incorrect notification per 4 min of observation was 
noted.
    The Navy plans to continue researching thermal detection systems 
for marine mammal detection to determine their effectiveness and 
compatibility with Navy applications. If the technology matures to the 
state where thermal detection is determined to be an effective 
mitigation tool during training and testing, NMFS and the Navy will 
assess the practicability of using the technology during training and 
testing events and retrofitting the Navy's observation platforms with 
thermal detection devices. The assessment will include an evaluation of 
the budget and acquisition process (including costs associated with 
designing, building, installing, maintaining, and manning the 
equipment); logistical and physical considerations for device 
installment, repair, and replacement (e.g., conducting engineering 
studies to ensure there is no electronic or power interference with 
existing shipboard systems); manpower and resource considerations for 
training personnel to effectively operate the equipment; and 
considerations of potential security and classification issues. New 
system integration on Navy assets can entail up to 5 to 10 years of 
effort to account for acquisition, engineering studies, and development 
and execution of systems training. The Navy will provide information to 
NMFS about the status and findings of Navy-funded thermal detection 
studies and any associated practicability assessments at the annual 
adaptive management meetings.
    Evidence regarding the current state of this technology does not 
support the assertion that the addition of these devices would 
meaningfully increase detection of marine mammals beyond the current 
rate (especially given the narrow field of view of this equipment and 
the fact that a Lookout cannot use standard equipment when using the 
thermal detection equipment) and, further, modification of standard 
Navy equipment, training, and protocols would be required to integrate 
the use of any such new equipment, which would incur significant cost. 
At this time, requiring thermal equipment is not warranted given the 
prohibitive cost and the uncertain benefit (i.e., reduction of impacts) 
to marine mammals. Likewise requiring the establishment of a pilot 
program is not appropriate. However, as noted above, the Navy continues 
to support research and technology development to improve this 
technology for potential future use.
    Comment 47: Multiple commenters stated that the Navy should also 
use passive acoustic monitoring in addition to Lookouts to detect 
Southern Resident killer whales and other marine mammals when doing 
active sonar training and testing. This will further expand awareness 
beyond what can be accomplished with visual Lookouts. The Navy proposes 
to use passive acoustic monitoring to look for marine mammals when 
undertaking certain other activities (e.g., explosive torpedoes), where 
passive acoustic assets are already part of an activity, but it does 
not include it as a mitigation measure for active sonar testing, which 
has the greatest anticipated impact on Southern Resident killer whales.
    Another commenter recommended that NMFS require the Navy to use 
passive (i.e., DIFAR and other types of sonobuoys) and active acoustic 
(i.e., tactical sonars that are in use during the actual activity or 
other sources similar to fish-finding sonars) monitoring, whenever 
practicable, to supplement visual monitoring during the implementation 
of its mitigation measures for all activities that could cause injury 
or mortality beyond those explosive activities for which passive 
acoustic monitoring already was proposed--at the very least, sonobuoys 
deployed and active sources and hydrophones used during an activity 
should be monitored for marine mammals.
    Response: The Navy does employ passive acoustic monitoring to 
supplement visual monitoring when practicable to do so (i.e., when 
assets that have passive acoustic monitoring capabilities are already 
participating in the activity). We note, however, that sonobuoys have a 
narrow band that does not overlap with the vocalizations of all marine 
mammals, and there is no bearing or distance on detections based on the 
number and type of devices typically used; therefore it is not possible 
to use these to implement mitigation shutdown procedures. For explosive 
events in which there are no platforms participating that have passive 
acoustic monitoring capabilities, adding passive acoustic monitoring 
capability, either by adding a passive acoustic monitoring device 
(e.g., hydrophone) to a platform already participating in the activity 
or by adding a platform with integrated passive acoustic monitoring 
capabilities to the activity (such as a sonobuoy), for mitigation is 
not practicable. As discussed in Section 5.5.3 (Active and Passive 
Acoustic Monitoring Devices) of the 2020 NWTT FSEIS/OEIS, which NMFS 
reviewed and concurs accurately assesses the practicability of 
utilizing additional passive or active acoustic systems for mitigation 
monitoring, there are significant manpower and logistical constraints 
that make constructing and maintaining additional passive acoustic 
monitoring systems or platforms for each training and testing activity 
impracticable. The Navy's existing passive acoustic monitoring devices 
(e.g., sonobuoys) are designed, maintained, and allocated to specific 
training units or testing programs for specific mission-essential 
purposes. Reallocating these assets to different training units or 
testing programs for the purpose of monitoring for marine mammals would 
prevent the Navy from using its equipment for its intended mission-
essential purpose. Additionally, diverting platforms that have passive 
acoustic monitoring capability would impact their ability to meet their 
Title 10 requirements and reduce the service life of those systems.
    Regarding the use of instrumented ranges for real-time mitigation, 
the commenter is correct that the Navy

[[Page 72350]]

continues to develop the technology and capabilities on its Ranges for 
use in marine mammal monitoring, which can be effectively compared to 
operational information after the fact to gain information regarding 
marine mammal response. There is no calibrated hydrophone array present 
in the NWTT area that is similar to the instrumented range off Kauai in 
the Hawaiian Islands or the range off San Clemente Island, California 
where such marine mammal monitoring has occurred. Further, the Navy's 
instrumented ranges were not developed for the purpose of mitigation. 
The manpower and logistical complexity involved in detecting and 
localizing marine mammals in relation to multiple fast-moving sound 
source platforms in order to implement real-time mitigation is 
significant. Although the Navy is continuing to improve its 
capabilities to use range instrumentation to aid in the passive 
acoustic detection of marine mammals, at this time it is not effective 
or practicable for the Navy to monitor instrumented ranges for the 
purpose of real-time mitigation for the reasons discussed in Section 
5.5.3 (Active and Passive Acoustic Monitoring Devices) of the 2020 NWTT 
FSEIS/OEIS.
    Regarding the use of active sonar for mitigation, we note that 
during Surveillance Towed Array Sensor System low-frequency active 
sonar (which is not part of this rulemaking, and uses a high-powered 
low frequency source), the Navy uses a specially designed adjunct high-
frequency marine mammal monitoring active sonar known as ``HF/M3'' to 
mitigate potential impacts. HF/M3 can only be towed at slow speeds 
(significantly slower than those used for ASW and the other training 
and testing uses contemplated for the NWTT activities) and operates 
like a fish finder used by commercial and recreational fishermen. 
Installing the HF/M3 adjunct system on the tactical sonar ships used 
during activities in this rule would have implications for safety and 
mission requirements due to impacts on speed and maneuverability. 
Furthermore, installing the system would significantly increase costs 
associated with designing, building, installing, maintaining, and 
manning the equipment. For these reasons, installation of the HF/M3 
system or other adjunct marine mammal monitoring devices as mitigation 
under the rule would be wholly impracticable. Further, NMFS does not 
generally recommend the use of active sonar for mitigation, except in 
certain cases where there is a high likelihood of injury or mortality 
(e.g., gear entanglement) and other mitigations are expected to be less 
effective in mitigating those effects. Active sonar generates 
additional noise with the potential to disrupt marine mammal behavior, 
and is operated continuously during the activity that it is intended to 
mitigate. On the whole, adding this additional stressor is not 
beneficial unless it is expected to offset, in consideration of other 
mitigations already being implemented, a high likelihood or amount of 
injury or mortality. For the Navy's NWTT activities, very few 
mortalities are authorized or anticipated, injury is of a small amount 
of low-level PTS, and the mitigation is expected to be effective at 
minimizing impacts. Further, the species most likely to incur a small 
degree of PTS from the Navy's activities are also the species with high 
frequency sensitivity that would be more likely to experience 
behavioral disturbance by the operation of the high frequency active 
source. For all of these reasons, NMFS does not recommend the use of 
active sonar to mitigate the Navy's training and testing activities in 
the NWTT Study Area.
    Comment 48: A commenter recommended that NMFS require the Navy to 
(1) allocate additional resources to the Lookout effectiveness study, 
(2) consult with the University of St. Andrews to determine how much 
additional data are necessary to analyze the data in a statistically 
meaningful manner, and (3) develop a plan to maximize the number of 
sightings (e.g., conducting cruises in Southern California rather than 
Hawaii) and complete the study as soon as possible.
    Response: The Lookout effectiveness study referenced by the 
commenter is still ongoing. This type of study has never been 
conducted, is extremely complex to ensure data validity, requires a 
substantial amount of data to conduct meaningful statistical analysis, 
and the Navy is committed to completing it. As noted by the commenter, 
there has not been enough data collected to conduct a sufficient 
analysis; therefore, drawing conclusions on an incomplete data set is 
not scientifically valid.
    However, NMFS has provided that the results of the Lookout 
effectiveness study will be made available by including a Term and 
Condition in the Endangered Species Act (ESA) Incidental Take 
Statements associated with this final rule and NMFS' 2020 final rule 
for Navy training and testing activities in the MITT Study Area, which 
requires the Navy to provide a report summarizing the status of and/or 
providing a final assessment on the Navy's Lookout Effectiveness Study 
following the end of Calendar Year (CY) 2021. The report must be 
submitted no later than 90 days after the end of CY2021. The report 
will provide a statistical assessment of the data available to date 
characterizing the effectiveness of Navy Lookouts relative to trained 
marine mammal observers for the purposes of implementing the mitigation 
measures.
    Comment 49: A commenter recommended that NMFS (1) require the Navy 
to determine whether it would be practicable to implement the proposed 
revised Southern Resident killer whale critical habitat areas, as 
depicted in the associated proposed rule (50 CFR 226.206(d)) and that 
fall within the NWTT Study Area but are not proposed to be excluded for 
national security purposes in section 226.206(c) of the proposed rule, 
as a mitigation area(s) that limits MF sonar and explosive training and 
testing activities and (2) if it is practicable, include the areas as a 
mitigation area(s) in the final rule or, if it is not practicable, 
justify why the areas were not included as a mitigation area(s) in the 
preamble to the final rule. If the mitigation area(s) is included in 
the final rule, the commenter further recommends that NMFS expand the 
mitigation area(s) as necessary if new information is made available 
(e.g., the proposed revised critical habitat is expanded in an 
associated final rule and the expanded area(s) overlaps the NWTT Study 
Area) during the timeframe under which the final rule would be valid. 
Another commenter also supported restricting activities in the proposed 
Southern Resident killer whale critical habitat.
    Response: NMFS and the Navy worked collaboratively during the ESA 
consultation and MMPA authorization processes to determine the 
effectiveness and practicability of implementing additional mitigation 
measures for marine mammals, including Southern Resident killer whales. 
NMFS worked with the Navy to refine the mitigation area measures 
pertaining to the use of explosives during Mine Countermeasure and 
Neutralization Testing to be more protective of ESA-listed species, 
including within areas that overlap proposed Southern Resident killer 
whale and proposed humpback whale critical habitats. Also, the final 
rule includes a new additional mitigation area, the Juan de Fuca Eddy 
Marine Species Mitigation Area, which includes important migration 
habitat for Southern Resident killer whales as they transit between 
Inland Waters and the Offshore Area (see the Mitigation Areas

[[Page 72351]]

section of this final rule and Section K.3.2.1.3 (Southern Resident 
Killer Whale) of the 2020 NWTT FSEIS/OEIS). Further expanding 
geographic mitigation requirements to include additional mitigation for 
proposed ESA critical habitat beyond this would be impractical for the 
Navy to implement for the reasons described in Appendix K (Geographic 
Mitigation Assessment) of the 2020 NWTT FSEIS/OEIS. For example, such 
further mitigation would encroach upon the primary water space where 
those training and testing activities occur in the NWTT Offshore Area 
for safety, sustainability, and mission requirements.
    Comment 50: A commenter recommended that NMFS (1) require the Navy 
to determine whether it would be practicable to implement both the 
Northern Washington Humpback Whale Feeding Area and the portion of the 
Northwest Washington Gray Whale Feeding Area that is within the NWTT 
offshore area as mitigation areas that limit MF sonar and explosive 
training and testing activities from May-November, consistent with the 
Humpback Whale Mitigation Areas proposed to be included and (2) if it 
is practicable, include the areas as mitigation areas in the final rule 
or, if it is not practicable, justify why the areas were not included 
as mitigation areas in the preamble to the final rule.
    Response: The Northwest Washington Gray Whale Feeding Area is 
located entirely within 12 nmi from shore in the Marine Species Coastal 
Mitigation Area and entirely within the Olympic Coast National Marine 
Sanctuary Mitigation Area. Therefore, due to the overlapping nature of 
the Navy's mitigation areas, mitigation within 12 nmi, 20 nmi, and 50 
nmi from shore in the Marine Species Coastal Mitigation Area and within 
the Olympic Coast National Marine Sanctuary Mitigation Area will be 
implemented throughout the Northwest Washington Gray Whale Feeding 
Area. Based on NMFS' mitigation requirements, the Navy will implement 
restrictions on the use of surface ship hull-mounted MF1 mid-frequency 
active sonar, will not use any explosives, and will not conduct Anti-
Submarine Warfare Tracking Exercise--Helicopter,--Maritime Patrol 
Aircraft,--Ship, or--Submarine training activities or non-explosive 
Anti-Submarine Warfare Torpedo Exercise--Submarine training activities 
(which involve the use of mid-frequency or high-frequency active sonar) 
within this gray whale feeding area.
    The Northern Washington Humpback Whale Feeding Area is located 
entirely within 50 nmi from shore, and partially within 20 nmi and 12 
nmi from shore in the Marine Species Coastal Mitigation Area. In 
addition, 90 percent of this feeding area is located within the Olympic 
Coast National Marine Sanctuary Mitigation Area. Based on NMFS' 
mitigation requirements, the Navy will implement restrictions on the 
use of surface ship hull-mounted MF1 mid-frequency active sonar in a 
portion of this feeding area, will not use explosives during training 
or testing (except explosive Mine Countermeasure and Neutralization 
Testing, which could occur in the 10 percent of this feeding area 
located outside of the Sanctuary Mitigation Area), and will not conduct 
Anti-Submarine Warfare Tracking Exercise--Helicopter,--Maritime Patrol 
Aircraft,--Ship, or--Submarine training activities or non-explosive 
Anti-Submarine Warfare Torpedo Exercise--Submarine training activities 
(which involve the use of mid-frequency or high-frequency active sonar) 
within a portion of this humpback whale feeding area. Expanding 
geographic mitigation requirements (including developing additional 
mitigation for these humpback whale or gray whale feeding areas) is not 
practicable for the Navy to implement for the reasons described in 
Appendix K (Geographic Mitigation Assessment) of the 2020 NWTT FSEIS/
OEIS. For example, such further mitigation would encroach upon the 
primary water space where those training and testing activities occur 
in the NWTT Offshore Area for safety, sustainability, and mission 
requirements.
    Comment 51: Commenters highlighted the need for NMFS to review the 
Navy's plans to rapidly increase its use of emerging technologies, 
including the use of unmanned underwater systems in Puget Sound and off 
the Washington coastline and the use of sonar, high-energy lasers, 
payload systems, kinetic energy weapons, and biodegradable polymers. 
One commenter stated that the proposed rule did not include a detailed 
analysis of potential impacts from these activities, and recommended 
that NMFS thoroughly analyze the impacts of these emerging technologies 
on marine mammals and prescribe any necessary mitigation measures, 
including seasonal restrictions and monitoring of short- and long-term 
impacts and careful testing and monitoring of the impacts of new 
technologies, to ensure that the Navy's activities have the least 
practicable adverse impact on marine mammals.
    Response: The analysis that the commenter has suggested is included 
in the Navy's rulemaking/LOA application, in the 2020 NWTT FSEIS/OEIS, 
and in the 2015 NWTT FEIS/OEIS. However, the effects conclusions and 
mitigation for emerging technologies are not broken out separately; 
they are included in the stressor-based analysis with other current 
technologies. NMFS has thoroughly reviewed and concurs with this 
analysis and it has been considered in the development of the final 
rule. NMFS and the Navy have coordinated extensively regarding which of 
the Navy's training and testing activities (including emerging 
technologies) are likely to result in the take of marine mammals. Some 
of the stressors the commenter noted were not identified as sources 
that would cause the incidental take of marine mammals, which is why 
they are not included in the Navy's MMPA application or discussed 
further in the rule. The commenter has offered no evidence showing that 
these emerging technologies (high energy lasers, kinetic energy 
weapons, or biodegradable polymers) would result in the incidental take 
of marine mammals.
    NMFS and the Navy clearly have considered the impacts of unmanned 
vehicles, and mitigation measures specific to these systems have been 
included in the rule. Mitigation in the Puget Sound and Strait of Juan 
de Fuca Mitigation Area specifically includes a limit of one Unmanned 
Underwater Vehicle Training activity annually at the Navy 3 OPAREA, 
Navy 7 OPAREA, and Manchester Fuel Depot (i.e., a maximum of one event 
at each location), and prohibits the use of low-frequency, mid-
frequency, or high-frequency active sonar during training or testing 
within the Puget Sound and Strait of Juan de Fuca Mitigation Area, 
unless a required element necessitates that the activity be conducted 
in NWTT Inland Waters during Unmanned Underwater Vehicle Training, and 
other activities as described in the Mitigation Areas section of this 
final rule. Also, since publication of the proposed rule, an additional 
measure has been added that requires Navy event planners to coordinate 
with Navy biologists prior to conducting Unmanned Underwater Vehicle 
Training at the Navy 3 OPAREA, Manchester Fuel Depot, Crescent Harbor 
Explosive Ordnance Disposal Range, and Navy 7 OPAREA. In addition, 
Unmanned Underwater Vehicle Training events at the Navy 3 OPAREA, 
Manchester Fuel Depot, Crescent Harbor Explosive Ordnance Disposal 
Range, and Navy 7 OPAREA will be cancelled or moved to another training 
location if the presence of Southern Resident killer whales is reported 
through available monitoring networks during the event planning

[[Page 72352]]

process, or immediately prior to the event, as applicable. 
Additionally, since publication of the proposed rule, another 
additional measure has been added, limiting the Navy to conducting a 
maximum of one Unmanned Underwater Vehicle Training event within 12 nmi 
from shore at the Quinault Range Site, and requiring the Navy to cancel 
or move Unmanned Underwater Vehicle Training events if Southern 
Resident killer whales are detected within 12 nmi from shore at the 
Quinault Range Site. This measure is expected to help avoid any 
potential impacts on Southern Resident killer whales during Unmanned 
Underwater Vehicle Training events.
    Comment 52: A commenter stated that dipping sonar, like hull-
mounted sonar, has been shown to be a significant predictor of deep-
dive rates in beaked whales. Evidence indicates that beaked whales dive 
deeper and stay at depth during exposure to mid-frequency active sonar 
(possibly to escape from the sound, as the lowest sound pressure levels 
occur at depth), behavior that also extends the inter-deep-dive-
interval (``IDDI,'' a proxy for foraging disruption). IDDIs were found 
to significantly lengthen upon exposure to mid-frequency sonar, with 
the longest, lasting 541 and 641 minutes, recorded during helicopter-
deployer sonar use at distances of about 17 and 11 km, respectively. 
These effects have been documented at substantially greater distances 
(about 30 km) than would otherwise be expected given the systems' 
source levels and the response thresholds developed from research on 
hull-mounted sonar. Deep-dive duration increases as distance to the 
helicopter decreases.
    The commenter states that helicopters deploy mid-frequency active 
sonar from a hover in bouts generally lasting under 20 minutes, moving 
rapidly between sequential deployments in an unpredictable pattern. 
That unpredictability may well explain the comparatively strong 
response of whales to these exposures, even though their duration of 
use and source level (217 dB) are generally well below those of hull-
mounted mid-frequency active sonar (235 dB). This finding is consistent 
with the wider stress literature, for which predictability is a 
significant factor in determining stress-response from acoustic and 
other stimuli (Wright et al., 2007). It should thus be presumed 
conservatively to apply to marine mammal species other than beaked 
whales. Notably, dipping sonar is deployed at depth, which may be 
another reason why it is relatively more impactful.
    The commenter states that NMFS has proposed authorizing take from 
as many as 41-50 annual testing events--amounting to 298 events across 
the seven-year authorization (as well as one training event across the 
seven-year period). The commenter states that NMFS must consider 
restricting or limiting use of dipping sonar during the present MMPA 
process.
    Response: The commenter appears to have misinterpreted the number 
of dipping sonar hours during testing events with the number of dipping 
sonar testing events. The Navy plans to conduct a maximum of one hour 
of MF4 sonar (Helicopter-deployed dipping sonars) for training over the 
seven-year period of this rule, and 41-50 hours of MF4 sonar annually 
for testing (298 hours total over the seven-year period of this rule). 
The final rule does include mitigation for and some restrictions on 
mid-frequency active sonar, including dipping sonar. For example, as 
described in the proposed rule, mitigation requirements within 12 nmi 
from shore prohibit Anti-Submarine Warfare Tracking Exercise--
Helicopter, Maritime Patrol Aircraft, Ship, or Submarine training 
activities (which involve mid-frequency active sonar, including MF4 
dipping sonar). The mitigation zone sizes and mitigation requirements 
were developed specifically for each applicable training and testing 
activity category or stressor. These mitigation zones are the largest 
area that (1) Lookouts can reasonably be expected to observe during 
typical activity conditions (i.e., most environmentally protective); 
and (2) can be implemented by the Navy without impacting safety, 
sustainability, or the ability to meet mission requirements. The 
mitigation measures included in this final rule represent the maximum 
level of mitigation that is practicable for the Navy to implement when 
balanced against impacts on safety, sustainability, and the ability of 
the Navy to continue meeting its mission requirements. Given the amount 
of dipping sonar and comparatively low associated impacts to marine 
mammals, along with the impracticability of including more 
restrictions, additional mitigation specific to dipping sonar is not 
warranted.
    Comment 53: Commenters stated that the Navy needs to incorporate 
better techniques to improve their detection rates of marine mammals, 
extend their exclusion zones around detected marine mammals, and 
utilize exclusion zones based on specific areas and times in their 
mitigation strategies.
    Response: The Navy uses active sonar during military readiness 
activities only when it is essential to training missions or testing 
program requirements since active sonar has the potential to alert 
opposing forces to the operating platform's presence. Passive sonar and 
other available sensors are used in concert with active sonar to the 
maximum extent practicable. The Navy, in coordination with NMFS, 
customized its mitigation zone sizes and mitigation requirements for 
each applicable training and testing activity category or stressor. 
Each mitigation zone represents the largest area that (1) Lookouts can 
reasonably be expected to observe during typical activity conditions 
(i.e., most environmentally protective) and (2) the Navy can commit to 
implementing mitigation without impacting safety, sustainability, or 
the ability to meet mission requirements. The current exclusion zones 
represent the maximum distance practicable for the Navy to implement, 
as described in Chapter 5 of the FSEIS/OEIS and, further, they 
encompass the area in which any marine mammal would be expected to 
potentially be injured. This final rule includes procedural mitigation 
and mitigation areas to further avoid or reduce potential impacts from 
active sonar on marine mammals in areas where important behaviors such 
as feeding and migration occur. For example, this final rule requires 
the Navy to restrict certain activities or types of sonar year-round 
within 12 nmi from shore in the Marine Species Coastal Mitigation Area, 
seasonally within the Point St. George Humpback Whale Mitigation Area 
and Stonewall and Heceta Bank Humpback Whale Mitigation Area, and year-
round in the Puget Sound and Strait of Juan de Fuca Mitigation Area to 
help avoid potential impacts from active sonar on marine mammals in 
important foraging and migration areas. Also, new mitigation requiring 
the Navy to only conduct explosive mine countermeasure and 
neutralization testing in daylight hours and in Beaufort Sea state 
number 3 conditions or less will increase the probability of detection 
of marine mammals and further increase the effectiveness of procedural 
mitigation zones. Additional information about the required mitigation 
is included in the Mitigation Measures section of this final rule, and 
in Appendix K (Geographic Mitigation Assessment) of the 2020 NWTT 
FSEIS/OEIS.
    Comment 54: A commenter stated that other agencies and operators 
are taking new, meaningful steps to reduce noise and disturbance 
affecting Southern Resident killer whales. The commenter stated that 
the Navy must also increase

[[Page 72353]]

its protections, or it will become responsible for a larger share of 
the cumulative impact and potentially negate some of the benefits of 
the other actions being taken. In 2019, Washington state took big steps 
to reduce impacts on Southern Resident killer whales from other vessel 
types, recognizing that noise and disturbance have significant adverse 
consequences for this endangered population. In May of that year, 
Governor Inslee signed into law a bill that increases the distance that 
vessels must stay away from Southern Resident killer whales and enacts 
a 7-knot speed limit within a half nautical mile of these killer 
whales. The legislature also allocated funding for a new hybrid ferry 
and funding to convert some ferries to hybrid-electric power. 
Washington State Ferries also started conducting a baseline noise 
inventory and working to develop solutions to address noise and 
frequencies of concern. In 2020, the Washington Department of Fish and 
Wildlife is developing rules for a commercial whale-watching license 
program to reduce the daily and cumulative impacts of vessel noise and 
disturbance on the Southern Resident killer whales. Meanwhile, in 2020, 
voluntary ship slowdowns will continue and expand through the Vancouver 
Fraser Port Authority-led Enhancing Cetacean Habitat and Observation 
(ECHO) Program--a Canadian program that directly benefits Southern 
Resident orcas in the inland waters. In 2019, 82 percent of large 
commercial ships participated in the slowdown. The Navy's contributions 
will take up a larger share of the underwater noise and disturbance as 
others reduce their impacts and the Navy continues to scale its 
activities up. The Navy should increase its own mitigation efforts so 
that there is still a significant net benefit to the Southern Resident 
killer whales in terms of reduced noise and disturbance when all these 
other entities are increasing their protective measures.
    Response: Please see the response to Comment 74 for more 
information regarding the low magnitude and severity of the anticipated 
impacts on Southern Resident killer whales. Also, of note, the standard 
operating procedures and mitigation the Navy uses to help avoid vessel 
strike would further help reduce exposure to vessel noise. Further, 
unlike commercial vessels, Navy vessel design generally incorporates 
quieting technologies in propulsion components, machinery, and the hull 
structure to reduce radiated acoustic energy. As a result, and in 
addition to comprising approximately one-tenth of one percent of total 
vessel traffic in Inland Waters, Navy vessels when present do not add 
significantly to ambient noise levels.
    Nonetheless, the number and/or intensity of incidents of take of 
Southern Resident killer whales will be minimized through the 
incorporation of mitigation measures, and NMFS has added mitigation 
measures for marine mammals, including Southern Resident killer whales, 
in this final rule. New measures include additional procedural 
mitigation during explosive mine countermeasure and neutralization 
testing; a new Juan de Fuca Eddy Marine Species Mitigation Area; and 
additional mitigation in the Marine Species Coastal Mitigation Area and 
the Olympic Coast National Marine Sanctuary Mitigation Area (both 
offshore areas that overlap with proposed Southern Resident killer 
whale critical habitat), as well as in the Puget Sound and Strait of 
Juan de Fuca Mitigation Area. This new mitigation is expected to 
benefit Southern Resident killer whales, in some cases by limiting or 
prohibiting certain activities in certain areas during times in which 
Southern Resident killer whales engage in important behaviors such as 
feeding and migration, and in other cases, by augmenting the 
effectiveness of procedural mitigation measures by requiring seasonal 
awareness messages or limiting activities to lower sea states when 
visibility is higher. With implementation of the new mitigation 
measures included in this final rule, we do not anticipate any take of 
Southern Resident killer whales in NWTT Inland Waters due to NWTT 
training and testing activities. These new mitigation measures are 
described in detail in the Mitigation Measures section of this final 
rule.
    These new measures, in combination with those included in the 
proposed rule, will reduce the severity of impacts to Southern Resident 
killer whales by reducing interference in feeding and migration that 
could result in lost feeding opportunities or necessitate additional 
energy expenditure to find other good foraging opportunities or 
migration routes. Procedural mitigations that alleviate the likelihood 
of injury, such as shutdown measures, also further reduce the 
likelihood of more severe behavioral responses.
    Additionally, the Navy has been a key contributor to marine species 
monitoring projects for a number of years to advance scientific 
knowledge of Southern Resident killer whales and the salmon they rely 
on. For decades, the Navy has implemented habitat improvement projects 
on its installations in Puget Sound that benefit Southern Resident 
killer whales.
    Comment 55: A commenter stated that although the Navy proposes to 
use surface-level Lookout systems for whales, these Lookouts are 
inadequate because (1) the visual range of human Lookouts is limited 
and (2) historically one-quarter of Navy tests have occurred at night, 
further limiting visibility.
    Response: NMFS acknowledges the limitations of Lookouts, does not 
assume that all marine mammals will be detected, and incorporates this 
information into its take estimates. Information about the quantitative 
analysis process, including the consideration of mitigation 
effectiveness, is described in detail in the 2018 technical report 
titled Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: 
Methods and Analytical Approach for Phase III Training and Testing. The 
Navy quantitatively assessed the effectiveness of its mitigation 
measures on a per-scenario basis for four factors: (1) Species 
sightability, (2) a Lookout's ability to observe the range to PTS (for 
sonar and other transducers) and range to mortality (for explosives), 
(3) the portion of time when mitigation could potentially be conducted 
during periods of reduced daytime visibility (to include inclement 
weather and high sea state) and the portion of time when mitigation 
could potentially be conducted at night, and (4) the ability for sound 
sources to be positively controlled (e.g., powered down).
    Appendix A (Navy Activities Descriptions) of the 2020 NWTT FSEIS/
OEIS includes details on seasonality and day/night requirements of the 
Navy's activities. Additionally, this final rule includes mitigation 
which prohibits the Navy from conducting explosive Mine Countermeasure 
and Neutralization Testing at night, as described in the Mitigation 
Measures section of this final rule, and in Chapter 5 (Mitigation) of 
the 2020 NWTT FSEIS/OEIS. As described in Section 5.5.1 (Active Sonar) 
of the 2020 NWTT FSEIS/OEIS, the Navy has a requirement to conduct some 
active sonar training and testing at night due to environmental 
differences between day and night and varying weather conditions that 
affect sound propagation and the detection capabilities of sonar. 
Temperature layers that move up and down in the water column and 
ambient noise levels can vary significantly between night and day. This 
affects sound propagation and could affect how sonar systems function 
and are operated. Therefore, it is not practicable to prohibit all 
active sonar activities

[[Page 72354]]

from being conducted at night due to impacts on mission requirements; 
however, after sunset and prior to sunrise, Lookouts and other Navy 
watch personnel employ night visual search techniques, which could 
include the use of night vision devices, as described in Section 5.2.1 
(Procedural Mitigation Development) of the 2020 NWTT FSEIS/OEIS. Please 
see the response to Comment 46 for discussion regarding use of thermal 
detection systems as a mitigation tool. Also, we note that visual 
mitigation is not the only tool; the Navy currently uses passive 
acoustic devices to the maximum extent practicable to aid in the 
detection of marine mammals.
    Comment 56: Commenters suggested that NMFS require the Navy to use 
an alternative method of training that does not have such a negative 
impact on marine life, such as sophisticated simulators and virtual 
explosives.
    Response: The Navy uses the necessary amounts of simulated and live 
training to accomplish their mission. As discussed in the 2015 NWTT 
Final EIS/OEIS Section 1.4.1 (Why the Navy Trains), simulators and 
synthetic training are critical elements that provide early skill 
repetition and enhance teamwork; however, they cannot replicate the 
complexity and stresses faced by Navy personnel during military 
missions and combat operations to which the Navy trains (e.g., anti-
submarine warfare training using hull-mounted mid-frequency active 
sonar). Just as a pilot would not be ready to fly solo after simulator 
training, operational Commanders cannot allow military personnel to 
engage in military missions and combat operations based merely on 
simulator training. In addition, as discussed in Section 2.4.1.5 
(Simulated Training and Testing Only) of the 2020 NWTT FSEIS/OEIS, the 
Navy currently uses simulation whenever possible (e.g., initial basic 
systems training, emergency procedures, and command and control 
exercises that are conducted without operational forces) and simulation 
plays a role in both antisubmarine warfare training and testing aboard 
ships, submarines, and aircraft and in aircrew training and testing.
    Comment 57: Commenters recommended that NMFS require the Navy to 
postpone or cancel any exercises when Lookouts detect marine mammals, 
specifically killer whales, within 1,000 yd (914.4 m) of the exercise, 
rather than the smaller zones included in the proposed rule, to 
mitigate long-term effects of noise exposure over an animal's lifetime. 
The commenters note that this minimum distance aligns with Washington 
State law which requires most vessels to slow down to 7 knots when 
within 0.5 nmi (0.9 km) of Southern Resident killer whales in order to 
mitigate noise impacts and disturbance. Other commenters recommended 
that the Navy cease any active mid-frequency sonar testing and 
exercises if any killer whales are sighted within .5 nmi, rather than 
the proposed 200-yd or 100-yd shutdown mitigation zone which is much 
closer than even the 300-yd and 400-yd approach distance for commercial 
whale watch operators and recreational boaters. Additionally, 
commenters stated that the Navy's use of mid-frequency sonar can impact 
wildlife within 2,000 mi\2\ (5180 km\2\), much farther than the 100 yd 
(91.4 m) proposed for some of the Navy's proposed activities. The 
commenter stated that although these activities may affect a wide range 
of marine mammals, the potential impact of these activities on 
endangered Southern Resident killer whales is of particular concern, 
given their dangerously low population size.
    Response: As described in the 2020 NWTT FSEIS/OEIS regarding 
shutdown requirements, the mitigation zone sizes and mitigation 
requirements in this rule are customized for each applicable training 
and testing activity category or stressor to protect specific 
biological resources from an auditory injury (PTS), non-auditory injury 
(from impulsive sources), or direct strike (e.g., vessel strike) to the 
maximum extent practicable. Mitigation zones were developed to be the 
largest area that (1) Lookouts can reasonably be expected to observe 
during typical activity conditions (i.e., most environmentally 
protective) and (2) the Navy can commit to implementing mitigation 
without impacting safety, sustainability, or the ability to meet 
mission requirements. NMFS has evaluated these recommendations for 
larger shutdown zones, and while larger shutdown zones might further 
reduce the potential or severity of the small amount of anticipated 
Level A harassment to some degree, we concur with the evaluation 
presented by the Navy indicating that increases in these zones are 
impracticable and have accordingly determined that larger shutdown 
zones are not warranted. The shutdown zones currently required for Navy 
activities, especially as coupled with other procedural mitigations and 
the required geographic mitigations, will effect the least practicable 
adverse impact on marine mammal species or stocks and their habitat.
    Regarding statements related to the areal extent of Navy effects, 
or distances noted in Washington State law, we note that the analysis 
conducted by the Navy and NMFS includes consideration of large areas 
such as those referenced by the commenters, through the application of 
the BRFs and the associated cutoff distances--in other words, effects 
at these distances are considered. However, avoiding all Level B 
harassment would be impossible to do while also conducting the 
activities analyzed, which is why the Navy has requested authorization. 
Further, we note that reference to Washington State measures is not 
comparable to mitigation required pursuant to an incidental take 
authorization, as the goal there is to minimize the likelihood of any 
take for unauthorized entities.
    The Navy has conducted active sonar and explosives training and 
testing activities in the Study Area for decades, and there is no 
evidence that routine Navy training and testing has negatively impacted 
marine mammal populations in the Study Area. NMFS' and the Navy's 
analyses were completed using the best available science, and include 
results from recently completed acoustic modeling. As discussed in the 
Mitigation Measures section of this final rule, and Chapter 5 
(Mitigation) of the 2020 NWTT FSEIS/OEIS, required mitigation will 
avoid or reduce potential impacts from NWTT activities on marine 
mammals, including Southern Resident killer whales (see response to 
Comment 74 for additional discussion regarding impacts to Southern 
Resident killer whales).

Monitoring

    Comment 58: A commenter stated that the Navy should clearly state 
that all appropriate personnel must have completed relevant training 
modules prior to participating in training and testing activities. 
Ensuring ``environmental awareness of event participants,'' including 
the possible presence of Southern Resident killer whales in the 
training location, implies that it is real-time situational awareness 
of potential killer whale presence. But it is in fact a series of 
modules in the Afloat Environmental Compliance Training Program, and 
``appropriate personnel'' will complete some or all of these modules at 
some time, with no defined timeline. There should be clear timeframes 
in which personnel will complete this training program. The commenter 
asserts that this mitigation measure is indisputably both available and 
practical.
    Response: As stated in the rule, ``All bridge watch personnel, 
Commanding Officers, Executive Officers, maritime patrol aircraft 
aircrews, anti[hyphen]submarine

[[Page 72355]]

warfare and mine warfare rotary-wing aircrews, Lookouts, and equivalent 
civilian personnel must successfully complete the Marine Species 
Awareness Training prior to standing watch or serving as a Lookout.'' 
Please see Table 35 for additional information regarding training 
requirements.
    Comment 59: A commenter recommended that, in addition to requiring 
long-term monitoring studies, NMFS should prioritize Navy research 
projects that aim to quantify the impact of training and testing 
activities at the individual, and ultimately, population-level. The 
commenter recommended detailed, individual-level behavioral-response 
studies, such as focal follows and tagging using DTAGs, carried out 
before, during, and after Navy operations, which can provide important 
insights for these species and stocks. The commenter stated that recent 
studies using DTAGs have also been used to characterize social 
communications between individuals of a species or stock, including 
between mothers and calves. The commenter recommended studies be 
prioritized that further characterize the suite of vocalizations 
related to social interactions. The commenter also stated that the use 
of unmanned aerial vehicles is also proving useful for surveying marine 
species, and can provide a less invasive approach to undertaking focal 
follows. Imagery from unmanned aerial vehicles can also be used to 
assess body condition and, in some cases, health of individuals. The 
commenter recommended that NMFS require the Navy to use these 
technologies for assessing marine mammal behavior before, during, and 
after Navy operations (e.g., swim speed and direction, group cohesion). 
The commenter also stated that studies into how these technologies can 
be used to assess body condition should be supported as this can 
provide an important indication of energy budget and health, which can 
inform the assessment of population-level impacts.
    Response: First, the Navy is pursuing many of the topics that the 
commenter identifies, either through the monitoring required under the 
MMPA or under the ESA, or through other Navy-funded Office of Naval 
Research (ONR) and Living Marine Resources (LMR) research programs. We 
are confident that the monitoring conducted by the Navy satisfies the 
requirements of the MMPA. A list of the monitoring studies that the 
Navy will be conducting under this rule is at the end of the Monitoring 
section of this final rule. Broadly speaking, in order to ensure that 
the monitoring the Navy conducts satisfies the requirements of the 
MMPA, NMFS works closely with the Navy in the identification of 
monitoring priorities and the selection of projects to conduct, 
continue, modify, and/or stop through the adaptive management process, 
which includes annual review and debriefs by all scientists conducting 
studies pursuant to the MMPA authorization. The process NMFS and the 
Navy have developed allows for comprehensive and timely input from 
NMFS, the Navy, the Marine Mammal Commission, and researchers 
conducting monitoring under the rule, which is based on rigorous 
reporting out from the Navy and the researchers doing the work. With 
extensive input from NMFS, the Navy established the Strategic Planning 
Process for Marine Species Monitoring to help structure the evaluation 
and prioritization of projects for funding. The Monitoring section of 
this rule provides an overview of this Strategic Planning Process. More 
detail, including the current intermediate scientific objectives, is 
available in section 5 (Mitigation), Section 5.1.2.2.1.3 (Strategic 
Planning Process) of the 2020 NWTT FSEIS/OEIS and on the monitoring 
portal (https://www.navymarinespeciesmonitoring.us/) as well as in the 
Strategic Planning Process report. The Navy's evaluation and 
prioritization process is driven largely by a standard set of criteria 
that help the internal steering committee evaluate how well a potential 
project would address the primary objectives of the monitoring program. 
Given that the Navy's Monitoring Program applies to all of the Navy's 
major Training and Testing activities and, thereby spans multiple 
regions and Study Areas to encompass consideration of the entire U.S. 
EEZ and beyond, one of the key components of the prioritization process 
is to focus monitoring in a manner that fills regionally specific data 
gaps, where possible (e.g., more limited basic marine mammal 
distribution data in the MITT Study Area), and also takes advantage of 
regionally available assets (e.g., instrumented ranges in the HSTT 
Study Area). NMFS has opportunities to provide input regarding the 
Navy's intermediate scientific objectives as well as to provide 
feedback on individual projects through the annual program review 
meeting and annual report. For additional information, please visit: 
https://www.navymarinespeciesmonitoring.us/about/strategic-planning-process/.
    The Navy's involvement with future research will continue to be 
developed and refined by the Navy and NMFS through the consultation and 
adaptive management processes, which regularly consider and evaluate 
the development and use of new science and technologies for Navy 
applications. Further, the Navy also works with NMFS to target and 
prioritize data needs that are more appropriately addressed through 
Navy research programs, such as the ONR and LMR programs. The Navy has 
indicated that it will continue to be a leader in funding of research 
to better understand the potential impacts of Navy training and testing 
activities and to operate with the least possible impacts while meeting 
training and testing requirements. Some of the efforts the Navy is 
leading or has recently completed are described below.
    (1) Individual-level behavioral-response studies--There are no ONR 
or LMR behavioral response studies in the NWTT Study Area given the 
limited number of activities conducted in NWTT in comparison to other 
ranges in the Pacific. However, many of the studies on species-specific 
reactions are designed to be applicable across geographic boundaries 
(e.g., Cuvier's beaked whale studies in the HSTT Study Area).
    (2) Tags and other detection technologies to characterize social 
communication between individuals of a species or stock, including 
mothers and calves--DTAGs are just one example of animal movement and 
acoustics tags. From the Navy's ONR and LMR programs, Navy funding is 
being used to improve a suite of marine mammal tags to increase 
attachment times, improve data being collected, and improve data 
satellite transmission. The Navy has funded a variety of projects that 
are collecting data that can be used to study social interactions 
amongst individuals. For example, as of September 2020 the following 
studies are currently being funded: Assessing performance and effects 
of new integrated transdermal large whale satellite tags 2018-2021 
(Organization: Marine Ecology and Telemetry Research); Autonomous 
Floating Acoustic Array and Tags for Cue Rate Estimation 2019-2020 
(Organization: Texas A&M University Galveston); Development of the next 
generation automatic surface whale detection system for marine mammal 
mitigation and distribution estimation 2019-2021 (Organization: Woods 
Hole Oceanographic Institution); High Fidelity Acoustic and Fine-scale 
Movement Tags 2016-2020 (Organization: University of Michigan); 
Improved Tag Attachment System for Remotely-deployed Medium-term 
Cetacean Tags 2019-2023 (Organization: Marine Ecology and Telemetry

[[Page 72356]]

Research); Next generation sound and movement tags for behavioral 
studies on whales 2016-2020 (Organization: University of St. Andrews); 
On-board calculation and telemetry of the body condition of individual 
marine mammals 2017-2021 (Organization: University of St. Andrews, Sea 
Mammal Research Unit); wide-band detection and classification system 
2018-2020 (Organization: Woods Hole Oceanographic Institution); and 
Extended Duration Acoustic Tagging 2016-2021 (Organization: Syracuse 
University).
    (3) Unmanned Aerial Vehicles to assess marine mammal behavior 
(e.g., swim speed and direction, group cohesion) before, during, and 
after Navy training and testing activities--Studies that use unmanned 
aerial vehicles to assess marine mammal behaviors and body condition 
are being funded by ONR's Marine Mammals and Biology program. Although 
the technology shows promise (as reviewed by Verfuss et al., 2019), the 
field limitations associated with the use of this technology have 
hindered its useful application in behavioral response studies in 
association with Navy training and testing events. For safety, research 
vessels cannot remain in close proximity to Navy vessels during Navy 
training or testing events, so battery life of the unmanned aerial 
vehicles has been an issue. However, as the technology improves, the 
Navy will continue to assess the applicability of this technology for 
the Navy's research and monitoring programs. An example project is 
integrating remote sensing methods to measure baseline behavior and 
responses of social delphinids to Navy sonar 2016-2019 (Organization: 
Southall Environmental Associates Inc.).
    (4) Modeling methods that could provide indicators of population-
level effects--NMFS asked the Navy to expand funding to explore the 
utility of other, simpler modeling methods that could provide at least 
an indicator of population-level effects, even if each of the 
behavioral and physiological mechanisms are not fully characterized. 
The ONR Marine Mammals and Biology program has invested in the 
Population Consequences of Disturbance (PCoD) model, which provides a 
theoretical framework and the types of data that would be needed to 
assess population level impacts. Although the process is complicated 
and many species are data poor, this work has provided a foundation for 
the type of data that is needed. Therefore, in the future, the relevant 
data pieces that are needed for improving the analytical approaches for 
population level consequences resulting from disturbances will be 
collected during projects funded by the Navy's marine species 
monitoring program. However, currently, PCoD models are dependent on 
multiple factors, one or more of which are often unknown for many 
populations, which makes it challenging to produce a reliable answer 
for most species and activity types, and further work is needed (and 
underway) to develop a more broadly applicable generalized construct 
that can be used in an impact assessment. As discussed in the 
Monitoring section of this rule, the Navy's marine species monitoring 
program typically supports 10-15 projects in the Pacific at any given 
time. Current projects cover a range of species and topics from 
collecting baseline data on occurrence and distribution, to tracking 
whales, to conducting behavioral response studies on beaked whales and 
pilot whales. The Navy's marine species monitoring web portal provides 
details on past and current monitoring projects, including technical 
reports, publications, presentations, and access to available data and 
can be found at: https://www.navymarinespeciesmonitoring.us/regions/pacific/current-projects/.
    In summary, NMFS and the Navy work closely together to prioritize, 
review, and adaptively manage the extensive suite of monitoring that 
the Navy conducts in order to ensure that it satisfies the MMPA 
requirements. NMFS has laid out a broad set of goals that are 
appropriate for any entity authorized under the MMPA to pursue, and 
then we have worked with the Navy to manage their projects to best 
target the most appropriate goals given their activities, impacts, and 
assets in the NWTT Study Area. Given the scale of the NWTT Study Area 
and the variety of activities conducted, there are many possible 
combinations of projects that could satisfy the MMPA standard for the 
rule. The commenter has recommended more and/or different monitoring 
than NMFS is requiring and the Navy is conducting or currently plans to 
conduct, but has in no way demonstrated that the monitoring currently 
being conducted does not satisfy the MMPA standard. NMFS appreciates 
the commenter's input, and will consider it, as appropriate, in the 
context of our adaptive management process, but is not requiring any 
changes at this time.
    Comment 60: Consistent with its responsibilities under the MMPA's 
provisions on unusual mortality events (section 1421c of the MMPA), as 
well as requirements under NEPA to obtain information essential to its 
analysis of reasonable alternatives (40 CFR 1502.22; now section 
1502.21), NMFS should urgently fund research to assess the extent of 
prey availability loss for California gray whales and to determine the 
cause of that loss of prey.
    Response: This comment is outside of the scope of this rulemaking, 
which must use the best available science to determine whether 
incidental take authorization should be issued under section 
101(a)(5)(A) of the MMPA, and which includes requirements for the Navy 
to implement certain mitigation and monitoring measures related to that 
incidental take. There is no information to indicate that prey 
availability loss for gray whales is related to the Navy's testing and 
training activities in the NWTT Study Area. Comments regarding NMFS' 
responsibilities under separate sections of the MMPA or NEPA, or 
recommendations that NMFS fund specific research under other sections 
of the MMPA, should be addressed to the appropriate NMFS office.
    Comment 61: A commenter stated that the Navy says it will make 
reports but questioned how their activities will be monitored. Another 
commenter requested an accounting of past operations and the damage 
done in the 10 years prior to this authorization.
    Response: Please refer to the Monitoring and Reporting sections of 
this final rule for an explanation of how the Navy's activities will be 
monitored and reported on. Additionally, the Navy's marine species 
monitoring web portal provides exercise reports for previous activities 
in the NWTT Study Area, as well details on past and current monitoring 
projects, including technical reports, publications, presentations, and 
access to available data. The Navy's marine species monitoring web 
portal can be found at: https://www.navymarinespeciesmonitoring.us/reporting/pacific/.
    Comment 62: A commenter stated that the Navy should reconsider the 
impacts of its proposed activities being imposed on Southern Resident 
killer whales, and examine alternatives and additional mitigation 
measures to ensure the protection and recovery of this population. The 
commenter recommended that if marine mammals are sighted or detected 
within acoustic range, then exercises should be shut down, if in 
progress, and postponed or moved elsewhere if the exercises have not 
yet started. The commenter stated that an appropriate threshold for 
such a decision is whenever noise levels from naval operations as well 
as other sources at the location of Southern Resident killer whales are 
expected to be greater than 130 dB re 1[mu]Pa, the pain

[[Page 72357]]

threshold of killer whales. The commenter states that these lower 
thresholds will extend far beyond the range at which marine mammals can 
be sighted from vessels responsible for explosives and mid-frequency 
active sonar. This will require the use of remote sensing technology 
such as drones (with infrared sensing capability for use at night) and 
sonobuoys. Two commenters suggested that the use of permanent 
hydrophone arrays wired to shore would allow more thorough tracking of 
marine mammal movement throughout the training range. In addition, 
exercises should be moved further offshore than currently planned to 
compensate for the greater ranges at which Level B takes could be 
expected under the criteria recommended here than for the 120 dB 
contour.
    Another commenter stated that the Navy should fund the installation 
of an array of underwater microphones along the coast of Washington 
state to provide near real-time information on the whereabouts of the 
Southern Resident killer whales as well as other cetaceans. This would 
serve as an important early warning system in the offshore area to 
complement the boat-based observers who have a limited visual range. 
Activities could then be planned based on Southern Resident killer 
whales movements and halted when Southern Resident killer whales are 
approaching well before they reach the 0.5 nmi distance. Hanson (2018) 
noted that 28 recorders would achieve a high probability of detection 
all along the Washington coast. The array would have the added benefit 
of improving monitoring of other killer whale populations, pilot 
whales, sperm whales, and beaked whales, allowing for improved 
implementation of mitigation measures to reduce incidental take of 
those species as well.
    Response: The Navy, in consultation with NMFS, used the best 
available science on marine mammal behavioral responses during acoustic 
exposures to develop appropriate behavioral response criteria and BRFs, 
which for odontocetes (including killer whales) predict that 
approximately 10-17 percent of exposures at 120-130 dB will result in 
behavioral responses that qualify as Level B harassment. For more 
information about the Phase III criteria, please refer to the technical 
report titled Criteria and Thresholds for U.S. Navy Acoustic and 
Explosive Effects Analysis (Phase III) (June 2017), available at 
www.nwtteis.com. NMFS and the Navy have also consulted with NMFS' ESA 
Interagency Cooperation Division under section 7 of the Endangered 
Species Act and will continue to coordinate on criteria and thresholds 
for assessing impacts to marine mammals.
    Additionally, as referenced in other comment responses, this final 
rule includes extensive mitigation that will minimize impacts to 
Southern Resident killer whales, including many additional measures 
added since the proposed rule. For example, the Navy is required to 
communicate with available sighting detection networks prior to the 
conduct of applicable activities in NWTT Inland Waters. Additionally, 
this final rule includes a new mitigation area in the NWTT Offshore 
Area known as the Juan de Fuca Eddy Marine Species Mitigation Area, 
where annual mid-frequency active sonar hours will be limited and 
explosives will be prohibited. It would not be practicable for the Navy 
to implement additional distance-from-shore restrictions or additional 
passive acoustic monitoring for the reasons provided in Appendix K 
(Geographic Mitigation Assessment) and Chapter 5 (Mitigation) of the 
2020 NWTT FSEIS/OEIS. NMFS has reviewed the analysis of additional 
potential restrictions and the impacts they would have on military 
readiness, and concurs with the Navy's assessment that they are 
impracticable. Additionally, the mitigation zones included in this 
final rule represent the largest zones practicable for the Navy to 
implement, as discussed in Comment 52. Therefore, the larger zones 
suggested by the commenter are not included in this final rule. 
Regarding the use of infrared and thermal technologies, please see the 
response to Comment 46.
    Regarding the installation of permanent hydrophone arrays wired to 
shore along the coast of Washington state to provide near real-time 
information on the whereabouts of the Southern Resident killer whales 
as well as other cetaceans, the cost and installation of such a system 
in and of itself would be a major federal undertaking that would 
require separate NEPA and permitting (Clean Water Act, essential fish 
habitat consultation, etc.) and is beyond the scope of mitigation that 
is necessary to meet the least practicable adverse impact standard. 
Further, given the low numbers and density of Southern Resident killer 
whales, combined with the relatively low number of training and testing 
activities, the benefits of such a detection network would be limited 
(i.e., we would expect few instances in which whales would be detected 
in an exact place and time that would intersect with a potential 
exercise, and thereby allow for an opportunity to mitigate). This 
recommendation is not warranted and, accordingly, NMFS has not included 
a requirement to install a hydrophone array for real-time mitigation 
monitoring.

Negligible Impact Determination

    Comment 63: A commenter stated that NMFS tabulates takes of marine 
mammal species but has not adequately assessed the aggregate impacts. 
The commenter asserted that, on the contrary, NMFS assumes, without any 
explanation, that the accumulated annual mortalities, injuries, 
energetic costs, temporary losses of hearing, chronic stress, and other 
impacts would not affect vital rates in individuals or populations, 
even though the Navy's activities would affect the same populations 
over time. This assumption seems predicated, for many species, on the 
unsupported notion that transient activity will not accumulate into 
population-level harm. The commenter stated that the proposed rule 
makes this assertion even for populations such as Hood Canal harbor 
seals and Washington Inland harbor porpoises, for which it estimates 
auditory injury, temporary hearing loss, and behavioral disruption at 
high numbers relative to the size of individual populations.
    Multiple commenters noted concern that the Hood Canal population of 
harbor seals would be taken 30.84 times its abundance each year, for 
seven years. Commenters said that NMFS observes that such high numbers 
of takes make it likely that females will suffer reproductive loss, yet 
it argues--without any quantitative support--that any such effects 
would be negligible on the population level because only a small number 
of individual females would be affected. Nowhere does NMFS consider the 
potential for sensitization, permanent habitat displacement, or other 
effects of repeated exposure that could exacerbate the already high 
numbers of takes.
    Commenters noted that other parties have conducted quantitative 
analysis of population consequences of disturbance, both in cases where 
substantial information is available for modeling and in cases where it 
is not--as is evident even in a three-year-old report from the National 
Academy of Sciences. NMFS cannot, the commenter asserts, discount the 
results of its take estimation without any quantitative or meaningful 
analysis. Its attempt to do so here for populations with high levels of 
take is unreasonable on its own terms and insupportable under the 
MMPA's standard of ``best available science.''
    Response: NMFS fully considered the potential for aggregate effects 
from all Navy activities and has applied a reasoned and comprehensive 
approach

[[Page 72358]]

to evaluating the effects of the Navy activities on marine mammal 
species and their habitat.
    No mortalities or non-auditory injuries are predicted from sonar or 
explosives for any marine mammal species, including harbor porpoises 
and harbor seals. The vast majority of impacts to marine mammals are 
instances of behavioral response, followed by instances of temporary 
threshold shift, both considered Level B harassment under the MMPA. A 
small proportion of a few species such as harbor porpoises are 
estimated to receive instances of mild PTS, however there is no 
information to indicate that the small amount of predicted PTS will 
affect the fitness of any individual. NMFS has explained in detail in 
the proposed rule and again in this final rule how the estimated takes 
were calculated for marine mammals, and then how the size of the Study 
Area across which activities may be distributed (and the ASW activities 
utilizing MF1 sonar, which account for the majority of the takes may 
occur anywhere in the Study Area and predominantly more than 12 nmi 
from shore) combined with the comparatively small number of takes as 
compared to the abundance of the species or stock in the area does not 
support that any individuals, other than Hood Canal harbor seals, will 
likely be taken over more than a few non-sequential days. We also 
considered UMEs (for species or stocks where applicable) to inform the 
baseline levels of both individual health and susceptibility to 
additional stressors, as well as stock status. Further, the species-
specific assessments in the Analysis and Negligible Impact 
Determination section pull together and address the combined injury, 
behavioral disturbance, and other effects of the aggregate NWTT 
activities (and in consideration of applicable mitigation) as well as 
other information that supports our determinations that the Navy 
activities will not adversely affect any species or stocks via impacts 
on rates of recruitment or survival.
    NMFS acknowledges that for the Hood Canal stock of harbor seals, 
though the majority of impacts are expected to be of a lower to 
sometimes moderate severity, the repeated takes over some number of 
sequential days for some individuals in this stock makes it more likely 
that some small number of individuals could be interrupted during 
foraging in a manner and amount such that impacts to the energy budgets 
of females (from either losing feeding opportunities or expending 
considerable energy to find alternative feeding options) could cause 
them to forego reproduction for a year (energetic impacts to males are 
generally meaningless to population rates unless they cause death, and 
it takes extreme energy deficits beyond what would ever be likely to 
result from these activities to cause the death of an adult marine 
mammal). However, we first note that the predicted potential number of 
repeated days of take for any individual has decreased significantly 
since the proposed rule (a reduction of more than 50 percent) as a 
result of harbor seal abundance corrections. Specifically, whereas the 
proposed rule suggested an average of 31 days of take with some subset 
of individuals experiencing more, the final rule predicts an average of 
10 days of incurred take per individual, with some potentially 
experiencing up to 21. The fewer the days per year on which take is 
likely incurred by any individual, the less likely those days will be 
sequential, and the lower the maximum number of sequential days, all of 
which makes it less likely that the behavioral impacts to any 
individuals would impact energetic budgets in a manner that would 
affect reproduction. Further, foregone reproduction (especially for 
only one year within seven, which is the maximum predicted because the 
small number anticipated in any one year makes the probability that any 
individual will be impacted in this way twice in seven years very low) 
has far less of an impact on population rates than mortality, and a 
relatively small number of instances of foregone reproduction would not 
be expected to adversely affect the stock through effects on annual 
rates of recruitment or survival, especially when the stock is 
increasing. As discussed in the Analysis and Negligible Impact 
Determination section for this analysis, there is documented evidence 
of an increasing population for Hood Canal harbor seals, including 
pupping on the Naval Base Kitsap Bangor waterfront in recent years (an 
area with high levels of human activity, including nearby pile driving, 
and associated noise). Further of note, the Navy has been conducting 
monitoring of harbor seals and porpoises in the vicinity of Naval Base 
Kitsap Bangor where pierside sonar use occurs, and harbor seals are 
noted in the waters around the piers daily and have become habituated 
to the high levels of noise at the industrial piers to the extent that 
they do not avoid the piers during active pile driving with impact 
hammers, which produce sounds almost as high as tactical sonar.
    Additionally, in the NWTT Study Area unit-level military readiness 
activities occur over a small spatial scale with few participants, 
typically over a short duration (a few hours or less), while larger-
scale training and testing events occur in locations outside of the 
Study Area. While data with which to quantify or analyze potentially 
synergistic impacts of multiple stressors are limited, substantial 
efforts are underway to better understand aggregate effects through 
data collection and improved analytical methods, such as the Population 
Consequences of Disturbance model (see Section 3.4.2.1.1.7, Long-Term 
Consequences in the 2020 NWTT FSEIS/OEIS). However, until there are 
sufficient data to inform such models, the best mechanism for assessing 
the impacts from Navy training and testing activities on marine mammal 
reproduction and survival includes monitoring the populations over time 
on Navy ranges. The Navy has conducted active sonar and explosives 
training and testing activities in the Study Area for decades, and 
there is no evidence that routine Navy training and testing has 
negatively impacted marine mammal populations in the Study Area (or at 
any Navy Range Complex). In addition, the Navy's research and 
monitoring programs described in the Monitoring section are focused on 
filling data gaps and obtaining the most up-to-date science to inform 
impact assessment. Information about prior and current research being 
conducted on marine mammals on Navy ranges is in Chapter 3.4 (Marine 
Mammals) of the 2020 NWTT FSEIS/OEIS and can be found at 
www.navymarinespeciesmonitoring.us.
    Comment 64: A commenter stated that NMFS did not meet the legal 
standard in the MMPA to find that the Navy's proposed actions ``will 
have a negligible impact on'' the species and stocks of marine mammals 
living in the NWTT Study Area. NMFS defines ``[n]egligible impact'' as 
an impact ``that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival.'' NMFS must make 
the negligible impact finding based on the ``best available science.'' 
However, the commenter says that NMFS does not adequately engage with 
identified impacts to vulnerable species, including Southern Resident 
killer whales and gray whales, analyze impacts of Naval aircraft, or 
address the role of climate change in exacerbating anticipated impacts 
of Naval activities. Another commenter also noted that multiple studies 
demonstrate behavior

[[Page 72359]]

impacts to cetaceans from aircraft, disagreed with the conclusion that 
aircraft do not result in harassment, and asked that NMFS ensure that 
any effects from aircraft result in a negligible impact on marine 
mammals (especially Southern Resident killer whales, given their 
status). For these reasons, the commenter asserts that NMFS cannot 
justify its finding of negligible impact based on the record in the 
proposed rule.
    Response: NMFS fully considered the potential for aggregate effects 
from all Navy activities, and discusses its consideration of these 
impacts, and its negligible impact determination for each species and 
stock in the Analysis and Negligible Impact Determination section of 
this final rule. As described throughout the rule, NFMS relied on the 
best available science in considering the impacts of the Navy's 
activities and in making the negligible impact determinations. NMFS 
fully considered the status of Southern Resident killer whales, gray 
whales, and all other marine mammals in its analysis, as discussed in 
the Description of Marine Mammals and Their Habitat in the Area of the 
Specified Activities and the Analysis and Negligible Impact 
Determination sections of the proposed and final rules. NMFS is 
required to analyze the impacts of the proposed authorized take in its 
negligible impact analysis--the effects of climate change are 
considered in the baseline of the status of marine mammal stocks in the 
rule, and further considered through the 2020 NWTT FSEIS/OEIS 
cumulative impact analysis (Chapter 4, Cumulative Impacts). NMFS 
acknowledges that climate change is impacting the marine environment in 
ways that could change our assessment of effects on marine mammals in 
the future, but the precise manner in which these changes would impact 
marine mammals and their habitat in the next seven years is both 
unpredictable and unquantifiable in the context of our analysis of the 
impacts of Navy activities, and NMFS' analysis is based on the best 
available scientific data.
    NMFS acknowledges the data demonstrating that marine mammals 
sometimes respond to aircraft overflights, however, we have evaluated 
the best available data and the Navy's activities and do not expect 
marine mammals to be affected in a manner that qualifies as Level B 
harassment. Information regarding behavioral reactions of marine 
mammals to aircraft is provided in Section 3.4.2.1.1.5 (Behavioral to 
Aircraft Noise) of the 2020 NWTT FSEIS/OEIS. Marine mammals have 
variable responses to aircraft, but overall little change in behavior 
has been observed during flyovers. Some odontocetes dove, slapped the 
water, or swam away from the direction of the aircraft during 
overflights; others did not visibly react (Richardson et al., 1995b). 
Beaked whales are more sensitive than other cetaceans (W[uuml]rsig et 
al., 1998). Killer whales demonstrated no change in group cohesion or 
orientation during survey airplane or unmanned aerial system flyovers 
(Durban et al., 2015; Smultea and Lomac-ManNair, 2016). It is unlikely 
that aircraft will randomly fly close enough to marine mammals (much 
less close enough over water at the moment that a cetacean surfaces) to 
evoke any response, and further unlikely that a marine mammal response 
to such an instantaneous exposure would result in that marine mammal's 
behavioral patterns being ``significantly altered or abandoned.'' 
Accordingly, the Navy did not request authorization for take resulting 
from aircraft overflights, and NMFS does not anticipate or authorize 
it.
    Comment 65: A commenter stated that the rates of take for 
populations of Dall's porpoises (131 percent of population abundance) 
and the populations of harbor porpoises on the Northern OR/WA Coast 
(244 percent of population abundance) and in Washington Inland Waters 
(265 percent of population abundance) are exceptionally high. As noted 
by NMFS, these porpoises are particularly vulnerable to the impacts of 
anthropogenic sound. NMFS recognizes that this level of take could also 
lead to reproductive loss, but again asserts, without thorough 
analysis, that it ``would not be expected to adversely impact annual 
rates of recruitment or survival.'' However, NMFS goes on to authorize 
these very high levels of take. The commenter asserts that such 
``cursory'' statements are not enough under the MMPA. Rather NMFS has a 
legal obligation to assess these impacts using the best available 
science.
    Response: The vulnerability of Dall's porpoise and harbor porpoise 
to sound is captured in the higher take estimate (as compared to other 
species in the NWTT Study Area), as this sensitivity is accounted for 
in the Navy's NAEMO model. NMFS erroneously indicated in the 
Preliminary Analysis and Negligible Impact Determination section of the 
proposed rule that the impacts to Dall's porpoises and harbor porpoises 
may cause them to forgo reproduction for a year. Given the expected 
low-level impacts and the mitigation included in this final rule, NMFS 
does not expect individuals from these species and stocks to forego 
reproduction, and NMFS has corrected this error in the final rule. The 
Analysis and Negligible Impact Determination section of this final rule 
includes a full discussion of NMFS' analysis of the impacts of the 
Navy's activities, and its negligible impact determinations for impacts 
to Dall's porpoise and harbor porpoise.
    Comment 66: A commenter stated that it strongly urges NMFS to 
revise its proposed authorization and mitigation measures to better 
protect Washington's marine mammals, including endangered Southern 
Resident killer whales, in accordance with the MMPA. The commenter 
stated that NMFS bases its authorization on inadequate data and does 
not require sufficient mitigation measures. The commenter asserted that 
as a result, NMFS' findings of negligible impact and least practicable 
adverse impact and proposed approval violate the MMPA and are further 
arbitrary and capricious under the Administrative Procedure Act.
    Response: In the final rule, NMFS fully considered the best 
available science, with the key scientific studies fully referenced 
throughout the rule. Additional science that was considered by both 
NMFS and the Navy is referenced in the 2020 NWTT FSEIS/OEIS.
    The rule also includes extensive mitigation measures for Southern 
Resident killer whales and other marine mammals that occur in 
Washington, including new measures since publication of the proposed 
rule. As discussed in the Mitigation Measures section of the rule, and 
in Chapter 5 (Mitigation) of the 2020 NWTT FSEIS/OEIS, the Navy will 
implement extensive mitigation to avoid or reduce potential impacts 
from the NWTT activities on marine mammals. These mitigation measures 
include mitigation areas that restrict certain activities in places and 
during times that are particularly important to Southern Resident 
killer whales and other marine mammals. One of these mitigation areas, 
the Puget Sound and Strait of Juan de Fuca Mitigation Area, encompasses 
the entire extent of NWTT Inland Waters in the state of Washington, 
including Southern Resident killer whale critical habitat. New 
mitigation measures in the Puget Sound and Strait of Juan de Fuca 
Mitigation Area will result in training and testing activities being 
conducted in NWTT Inland Waters only when necessitated by mission-
essential training or testing program requirements. With implementation 
of the new mitigation measures included in this final rule, we do not 
anticipate any take of Southern Resident killer whales in NWTT Inland 
Waters due to

[[Page 72360]]

NWTT training and testing activities. This final rule also includes 
additional mitigation measures for Southern Resident killer whales in 
other mitigation areas, including the Marine Species Coastal Mitigation 
Area and the Olympic Coast National Marine Sanctuary Mitigation Area. 
Please refer to the Mitigation Measures section of this final rule for 
further discussion of the required mitigation measures in the NWTT 
Study Area.
    Having considered all of the pertinent science available to the 
agency (of which just the key studies have been referenced in the rule) 
and the full suite of mitigation measures to reduce impacts, the final 
rule provides a thorough discussion of the least practicable adverse 
impact and negligible impact analyses and determinations in the 
Mitigation Measures and Analysis and Negligible Impact Determination 
sections, respectively.
    Comment 67: Gray whales are currently undergoing an unexplained 
die-off leading to 352 strandings between January 2019 and July 2020, 
including 44 strandings along the coast of Washington alone. NOAA is 
investigating the die-off as an Unusual Mortality Event. While it is 
not clear what specifically is driving this event, many animals show 
signs of ``poor to thin body condition.'' The commenter states that in 
the proposed rule, NMFS relies on the increasing population of the 
stock to assert that the Navy's proposed takes will not be exacerbated 
by the Unusual Mortality Event to the point of affecting annual rates 
of recruitment or survival. However, as the exact cause of the Unusual 
Mortality Event is not known, NMFS also cannot know if the current 
Unusual Mortality Event is indicative of a longer-term trend in the 
population, potentially linked to the impacts of climate change. NMFS' 
reliance on an increasing stock may be misplaced, particularly in light 
of the fact that NMFS will authorize the Navy's activities for a seven-
year period during which the health of the gray whale population could 
decline.
    Response: NMFS does not rely solely on the increasing stock size 
for gray whales as the commenter suggests. As discussed in the Analysis 
and Negligible Impact Determination section of this final rule, NMFS is 
authorizing one mortality over the seven years covered by this rule, or 
0.14 mortality annually. The addition of this 0.14 annual mortality 
still leaves the total annual human-caused mortality well under both 
the insignificance threshold and residual PBR (which is 661.6). No 
mortality from explosives and no Level A harassment is anticipated or 
authorized. Altogether, while we have considered the impacts of the 
gray whale UME, this population of gray whales is not endangered or 
threatened under the ESA and the best available science at this time 
indicates the stock is increasing. Additionally, only a very small 
portion of the stock is anticipated to be impacted by Level B 
harassment (less than 1 percent) and any individual gray whale is 
likely to be disturbed at a low-moderate level. This low magnitude and 
moderate-lower severity of harassment effects is not expected to result 
in impacts to reproduction or survival for any individuals, nor are 
these harassment takes combined with the authorized mortality of one 
whale over the seven-year period expected to adversely affect this 
stock through impacts on annual rates of recruitment or survival. For 
these reasons, NMFS determined, in consideration of all of the effects 
of the Navy's activities combined, that the authorized take will have a 
negligible impact on the Eastern North Pacific stock of gray whales.
    Additionally, this final rule includes extensive mitigation for 
gray whales, including in the Marine Species Coastal, Olympic Coast 
National Marine Sanctuary, Stonewall and Heceta Bank Humpback Whale, 
Point St. George Humpback Whale, and Northern Puget Sound Gray Whale 
Mitigation Areas, which overlap with important gray whale foraging and 
migration areas.

NEPA

    Comment 68: Commenters stated that NMFS cannot rely on the Navy's 
deficient EIS to satisfy NMFS' NEPA obligations when issuing 
regulations or permits under the MMPA. The commenter states that NMFS 
must prepare a separate EIS, or, at minimum, a supplemental EIS, before 
proceeding with the proposed action. The commenter stated that the 
Navy's DSEIS is deficient on its face. One commenter asserted that 
those deficiencies include, but are not limited to: Failing to take a 
hard look at the effects of the action to endangered Southern Resident 
killer whales and other sensitive species, failing to take a hard look 
at the effects of the proposed training and testing activities, 
including modeling, thresholds, and assumptions about harm that 
underestimate the extent and severity of marine mammal take (both 
behavioral impacts and injury), failing to take a hard look at the 
effects of the entire action, failing to evaluate a full range of 
reasonable alternatives, failing to evaluate a full range of reasonable 
mitigation measures, failing to accurately estimate the amount of take 
and impact of all the activity covered by the SEIS, and failing to 
consider the cumulative impacts of noise and other stressors in 
conjunction with other reasonably foreseeable activities. Commenters 
stated that the final rule should not be issued until after NMFS 
completes a proper NEPA analysis.
    Response: Consistent with the regulations published by the Council 
on Environmental Quality (CEQ), it is common and sound NEPA practice 
for NMFS to participate as a cooperating agency and adopt a lead 
agency's NEPA analysis when, after independent review, NMFS determines 
the document to be sufficient in accordance with 40 CFR 1506.3. 
Specifically here, NMFS is satisfied that the 2020 NWTT FSEIS/OEIS 
adequately addresses the impacts of issuing the MMPA incidental take 
authorization (including in its assessment of effects to Southern 
Resident killer whales, and in consideration of the effects of the 
entire action) and that NMFS' comments and concerns have been 
adequately addressed. The FSEIS/OEIS takes a hard look at all of the 
issues specifically raised by the commenter. NMFS' early participation 
in the NEPA process and role in shaping and informing analyses using 
its special expertise ensured that the analysis in the 2020 NWTT FSEIS/
OEIS is sufficient for purposes of NMFS' own NEPA obligations related 
to its issuance of incidental take authorization under the MMPA.
    Regarding the alternatives and mitigation measures, NMFS' 
involvement in development of the 2020 NWTT FSEIS/OEIS and role in 
evaluating the effects of incidental take under the MMPA ensured that 
the 2020 NWTT FSEIS/OEIS includes adequate analysis of a reasonable 
range of alternatives. The 2020 NWTT FSEIS/OEIS includes a No Action 
Alternative specifically to address what could happen if NMFS did not 
issue an MMPA authorization. The FSEIS/OEIS also includes and analyzes 
two action alternatives (including mitigation measures incorporated 
into the action alternatives) to evaluate the impacts of an MMPA 
incidental take authorization that would also meet the current and 
future (seven-year) training and testing requirements to ensure the 
Navy meets its Title 10 responsibilities, which includes to maintain, 
train, and equip combat ready forces. As noted, these alternatives 
fully analyze a comprehensive variety of mitigation measures. This NEPA 
mitigation analysis supported NMFS' evaluation of our mitigation 
options in potentially issuing an MMPA authorization, which, if the 
authorization can be issued under

[[Page 72361]]

the negligible impact standard, primarily revolves around the 
appropriate mitigation to prescribe. This approach to evaluating a 
reasonable range of alternatives is consistent with NMFS policy and 
practice for issuing MMPA incidental take authorizations. NMFS has 
independently reviewed and evaluated the 2020 NWTT FSEIS/OEIS, 
including the range of alternatives, and determined that the 2020 NWTT 
FSEIS/OEIS fully satisfies NMFS' NEPA obligations related to its 
decision to issue the MMPA final rule and associated LOAs, and we have 
adopted it.
    Comment 69: Commenters stated that NMFS cannot rely on the 2020 
NWTT FSEIS/OEIS to fulfill its obligations under NEPA because it does 
not adequately address NMFS' own actions and responsibilities under the 
MMPA. The commenter stated that the MMPA requires NMFS to protect and 
manage marine mammals, allowing incidental take of marine mammals only 
in limited circumstances when such take satisfies the Act's statutory 
requirements, including the ``negligible impact'' and ``least 
practicable adverse impact'' standards. In other words, NMFS is charged 
under the MMPA with prioritizing the protection of species. The 
commenter states that the Navy, on the other hand, seeks primarily to 
maximize its opportunities for training and testing activities. Thus, 
the Navy's SEIS is framed around a fundamentally different purpose and 
need--one that is incongruent with NMFS' obligations under the MMPA.
    Response: The proposed action is the Navy's proposal to conduct 
testing and training activities in the NWTT Study Area. NMFS is a 
cooperating agency, as it has jurisdiction by law and special expertise 
over marine resources impacted by the Navy's action, including marine 
mammals and federally-listed threatened and endangered species. As 
discussed in Comment 68, NMFS has adopted the 2020 NWTT FSEIS/OEIS 
after determining that the document is sufficient under the CEQ 
regulations at 40 CFR 1506.3. Specifically, NMFS is satisfied that the 
FSEIS/OEIS adequately addresses the impacts of issuing the MMPA 
incidental take authorization and that NMFS's comments and concerns 
have been adequately addressed. There is no requirement in the CEQ 
regulations that NMFS, as a cooperating agency, have a separate purpose 
and need statement in order to ensure adequacy and sufficiency for 
adoption. Nevertheless, the statement of purpose and need in the 2020 
NWTT FSEIS/OEIS explicitly acknowledges NMFS' purpose of evaluating the 
Navy's proposed action and making a determination whether to issue the 
MMPA regulations and LOAs. NMFS' early participation in the NEPA 
process and role in shaping and informing analyses using its special 
expertise ensured that the analysis in the 2020 NWTT FSEIS/OEIS is 
sufficient for purposes of NMFS' own NEPA obligations related to its 
issuance of incidental take authorization under the MMPA.
    Comment 70: Commenters stated that their organizations are aware 
that on July 16, one day before the conclusion of the comment period, 
CEQ issued new regulations governing the preparation of environmental 
assessments and environmental impact statements under NEPA. The 
commenters stated that they believe these new regulations contain 
numerous provisions that are contrary to law and destructive of federal 
environmental decision-making. Agencies that have begun the NEPA 
process for a particular agency action prior to September 14, 2020, as 
is the case with NWTT, have discretion under the new regulations at 40 
CFR 1506.13 to decide whether to apply them. The commenters stated that 
given the legal infirmities of the new CEQ regulations, they strongly 
recommend that NMFS elect not to apply them here; and NMFS should make 
that choice clear in its EIS.
    Response: The effective date of the 2020 CEQ NEPA regulations was 
September 14, 2020. As noted by the commenter, NEPA reviews initiated 
prior to the effective date of the 2020 CEQ regulations may be 
conducted using the 1978 version of the regulations. The NEPA review 
for this rulemaking and the Navy's proposed action began prior to 
September 14, 2020, and the agencies decided to proceed under the 1978 
CEQ regulations. Therefore, the new CEQ regulations were not applied to 
the 2020 NWTT FSEIS/OEIS, and the FSEIS/OEIS was prepared using the 
1978 CEQ NEPA regulations.
    Comment 71: A commenter stated that the Navy's MMPA application was 
premature because the 2020 NWTT FSEIS/OEIS had not been finalized. The 
commenter questioned what activities would occur in the Olympic Coast 
National Marine Sanctuary prior to finalization of the 2020 NWTT FSEIS/
OEIS.
    Response: The commenter misunderstands the timing of the analysis 
of environmental impacts under NEPA and NMFS' consideration of an 
application for MMPA incidental take authorization. The NEPA analysis, 
along with consideration of other applicable laws, must be completed 
before a decision is made to issue a final rule authorizing incidental 
take under the MMPA, but the NEPA analysis does not need to be 
completed before an MMPA application is submitted. The Navy submitted 
their application while the NWTT SEIS/OEIS was in development. NMFS and 
the Navy coordinated on development of the NWTT SEIS/OEIS, and the 
final rule authorizes Navy training and testing activities beginning in 
November 2020. Any Navy testing and training activities occurring in 
the Olympic Coast National Marine Sanctuary prior to finalization of 
this rule and the 2020 NWTT FSEIS/OEIS were conducted under the 
previous MMPA incidental take authorization and its accompanying NEPA 
analysis.

ESA

    Comment 72: A commenter stated that NMFS must ensure that the 
Navy's activities will not jeopardize endangered species in the NWTT 
Study Area, including the Southern Resident killer whale population, as 
required by the ESA, and that NMFS and the Navy must fully comply with 
their obligations under the ESA. Another commenter stated that NMFS' 
consultation must also evaluate the impacts of the proposed action 
beyond ESA-listed marine mammals and their habitat, to include the 
other threatened and endangered species that will be affected by the 
Navy activities. The commenter specifically references designated 
critical habitat for endangered Pacific leatherback sea turtles in the 
NWTT Study Area, and that more than two dozen listed populations of 
Pacific salmon and Steelhead occur in the Study Area. The commenter 
states that NMFS has a duty to ensure against jeopardy for each of 
these, and any other, imperiled species in this area. Another commenter 
stated that this authorization violates NMFS' own Recovery Plan for 
U.S. Pacific Populations of the Leatherback Turtle. Another commenter 
stated that NMFS should require the Navy to shift testing and training 
activities away from locations and seasonal windows that endangered 
species are present.
    Response: NMFS' Permits and Conservation Division has completed ESA 
consultation with NMFS' ESA Interagency Cooperation Division on whether 
the promulgation of this rule and issuance of the associated LOAs are 
likely to jeopardize the continued existence of any ESA-listed species 
or destroy or adversely modify any designated critical habitat, while 
the Navy has consulted on all ESA-listed

[[Page 72362]]

species that may be affected by their action. NMFS' ESA Interagency 
Cooperation Division's biological opinion includes analysis and 
determinations regarding all ESA-listed species and designated critical 
habitat that may be affected by the Navy's or NMFS' actions in the NWTT 
Study Area. The biological opinion concluded that NMFS' and the Navy's 
proposed actions are not likely to jeopardize the continued existence 
of any endangered or threatened species and are not likely to destroy 
or adversely modify designated critical habitat.
    The commenter does not explain in what manner they think 
authorizing incidental take of marine mammals under the MMPA would 
violate the ESA recovery plan for U.S. Pacific populations of 
leatherback turtles. ESA recovery plans are guidance documents that 
provide recommended recovery actions for NMFS, other federal agencies, 
States, tribes, NGOs, and other stakeholders to recover the species, 
and as such it is not possible to ``violate'' a recovery plan. That 
said, we have reviewed the recovery plan and there are no recovery 
actions related to Navy activities or authorization of incidental take 
of marine mammals.
    Neither the ESA nor the MMPA preclude activities in locations and 
times where endangered species are present. As described in the ESA 
biological opinion, NMFS made the preliminary findings necessary to 
allow for incidental take of ESA-listed marine mammals in the proposed 
MMPA rule. The biological opinion is accompanied by an ESA incidental 
take statement that, among other things, exempts the incidental take 
from ESA section 9 liability and identifies reasonable and prudent 
measures to minimize the impact of the anticipated incidental take. As 
described in the Mitigation Measures section of this rule, geographic 
mitigations required by this rule limit activities in some areas where 
ESA-listed species (e.g., the Southern Resident killer whale) are 
present in higher densities or exhibit important behaviors.
    Comment 73: A commenter stated that NMFS cannot finalize the 
proposed incidental take regulations or issue any LOAs until it 
completes consultation and imposes limits to mitigate the hazards of 
Navy's training and testing on threatened and endangered species and 
their habitats and also must require additional mitigation. The 
commenter further stated that in complying with the ESA, NMFS must 
consider the appreciable impact of the proposed activities on listed 
species and their habitats. The commenter stated that the consultation 
must evaluate the programmatic impact of seven years of Navy training 
and testing as authorized by NMFS in final regulations, and in addition 
to completing programmatic consultation, NMFS must also consult on a 
site-specific basis prior to issuing or modifying LOAs. The commenter 
states that NMFS, however, cannot avoid programmatic consultation by 
deferring to partial, LOA-specific consultations.
    The commenter asserts that if other activities or conditions also 
harm an endangered species or its habitat, the effects of NMFS' 
authorization of the Navy's activities must be added to that baseline 
and analyzed together to determine whether the proposed activity 
jeopardizes the species or adversely modifies critical habitat, and 
states that in the NWTT Study Area, threatened and endangered species 
along the coast are exposed to a variety of threats from ship strikes, 
oil and gas activities, noise from vessels, entanglement or bycatch in 
fishing gear, wastewater discharge, oil spills, as well as other 
cumulative impacts from fishing, shipping, military activities, and 
climate change. The commenter states that the aggregate impact of these 
activities must be considered in the consultation.
    Response: NMFS agrees that we could not finalize these regulations 
or issue LOAs until we completed consultation under section 7 of the 
ESA. NMFS' Permits and Conservation Division, which developed this 
rule, consulted with NMFS' ESA Interagency Cooperation Division on the 
promulgation of this seven-year rule and issuance of the associated 
LOAs which authorize incidental take of marine mammals in the NWTT 
Study Area. As required, the consultation included the necessary 
consideration of the environmental baseline, impacts on ESA listed 
species and their habitat over the seven years of the rule, and 
cumulative effects. As noted in the Endangered Species Act section of 
this rule, NMFS' ESA Interagency Cooperation Division has issued a 
biological opinion concluding that the promulgation of this seven-year 
rule and issuance of subsequent LOAs are not likely to jeopardize the 
continued existence of threatened and endangered species under NMFS' 
jurisdiction and are not likely to result in the destruction or adverse 
modification of designated (or proposed) critical habitat in the NWTT 
Study Area. The Biological Opinion for this rulemaking is available at 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.
    As discussed in the Mitigation Measures section and multiple 
responses to Comments, this final rule includes extensive mitigation 
measures to lessen the frequency and severity of impacts from the 
Navy's activities on marine mammals and their habitat, including those 
that are listed as threatened or endangered. Please refer to the 
biological opinion for additional information about ESA-listed species 
and additional mitigation required for ESA-listed species other than 
marine mammals.

Southern Resident Killer Whale

    Comment 74: Multiple commenters noted that the amended Navy 
application and NMFS' proposed rule now predict and would allow for a 
vastly increased level of incidental take--formerly 2 takes of Southern 
Resident killer whales, now 51 takes--every year. One commenter stated 
that approval of such a high level of incidental take without requiring 
any additional mitigation measures represents gross neglect of the 
agency's management responsibilities under the ESA and the MMPA to 
avoid or mitigate impacts to this highly endangered and iconic species. 
A commenter also stated that many organizations and Washington state 
agencies have asked for enhanced mitigation measures to reduce adverse 
impacts on Southern Resident killer whales; other commenters echoed 
this recommendation. The commenter asserted that these measures are not 
expected to impact the Navy's ability to carry out its national 
security mission, and yet they do not seem to have been considered, let 
alone adopted in the proposed rule. Furthermore, mitigation measures 
considered sufficient when the Navy thought the density of Southern 
Resident killer whales offshore was much lower should not be considered 
sufficient now that the Navy knows it is higher based on more recent 
data. Commenters also urged NMFS to change its preliminary 
determination of ``negligible impact'' and require additional 
monitoring and mitigation measures to significantly reduce the 
incidental take of Southern Resident killer whales so that it does in 
fact warrant a ``negligible impact'' determination.
    A commenter stated that while the MMPA allows permitted incidental 
take of certain activities if the take is of small numbers, with no 
more than a ``negligible impact,'' defined as one that ``cannot be 
reasonably expected to, and is not reasonably likely to, adversely

[[Page 72363]]

affect the species or stock through effects on annual rates of 
recruitment or survival,'' a take of 51 individual Southern Resident 
killer whales per year cannot be considered to be ``of small numbers'' 
nor unlikely to ``adversely affect'' the species. Multiple commenters 
echoed this concern. A commenter also stated that displacement from 
preferred foraging areas will cause population-level effects that could 
extend into the future given the highly social nature of the Southern 
Resident killer whale community and transmission of information between 
associated individuals. The commenter stated that there are documented 
cases of naval activities causing Southern Resident killer whales to 
abruptly change their behavior and abandon foraging activities and 
areas, most notably the USS Shoup active sonar incident in 2003. More 
recently, the Canadian Navy set off explosives near a group of Southern 
Resident killer whales from L pod, in federally protected critical 
habitat, causing them to flee the area.
    Response: This increase in incidental take of Southern Resident 
killer whales between Phase II and Phase III of the Navy's activities 
is partially due to new offshore Southern Resident killer whale density 
estimates and analytical factors, and partially due to increased 
activity levels in the Navy's Phase III activities.
    The number and/or intensity of incidents of take will be minimized 
through the incorporation of mitigation measures, which were expanded 
from the last rule in the Navy's application and the proposed rule. 
Further, since publication of the proposed rule NMFS has added 
mitigation measures for marine mammals, including Southern Resident 
killer whales, in this final rule. New measures include additional 
procedural mitigation during explosive mine countermeasure and 
neutralization testing and new geographic mitigation measures, 
including a new Juan de Fuca Eddy Marine Species Mitigation Area and 
additional mitigation in the Marine Species Coastal Mitigation Area and 
the Olympic Coast National Marine Sanctuary Mitigation Area (both of 
which are offshore areas that overlap with ESA proposed Southern 
Resident killer whale critical habitat), as well as in the Puget Sound 
and Strait of Juan de Fuca Mitigation Area. This new mitigation will 
benefit Southern Resident killer whales, in some cases by limiting or 
prohibiting certain activities in certain areas during times in which 
Southern Resident killer whales engage in important behaviors such as 
feeding and migration, and in other cases, by augmenting the 
effectiveness of procedural mitigation measures by requiring seasonal 
awareness messages or limiting activities to lower sea states when 
visibility is higher. These new mitigation measures are described in 
detail in the Mitigation Measures section of this final rule.
    These new measures, in combination with those included in the 
proposed rule, will reduce the severity of impacts to Southern Resident 
killer whales by reducing interference in feeding and migration that 
could result in lost feeding opportunities or necessitate additional 
energy expenditure to find other good foraging opportunities or 
migration routes. Procedural mitigations that avoid the likelihood of 
injury, such as shutdown measures, also further reduce the likelihood 
of more severe behavioral responses.
    The 51 takes of Southern Resident killer whales, only two of which 
are estimated to involve TTS, each represent a day in which one 
individual whale is predicted to be exposed above the behavioral 
harassment threshold (or in two cases, above the TTS threshold), which 
is discussed in detail in the Analysis and Negligible Impact 
Determination section of this final rule as well as the Navy's 2017 
Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects 
Analysis (Phase III) report. This means that either 51 individual 
whales are exposed above these thresholds on one day within a year, or 
some fewer number of individuals might be exposed on two or three days 
(but no more than 51 total exposure days so, for example, 25 
individuals exposed on two days each within a year and one individual 
exposed on one day). Also, modeling supports the prediction that, given 
the movement of the animals and the characteristics of the testing and 
training activities, the duration of any exposure is expected to be 
relatively short, not more than seconds or minutes, or occasionally 
hours. As discussed in the Analysis and Negligible Impact Determination 
section of this final rule, even acknowledging the small and declining 
stock size of the Southern Resident DPS of killer whales (which is the 
same as the Eastern North Pacific Southern Resident stock under the 
MMPA), this low magnitude and severity of harassment effects is 
unlikely to result in impacts on individual reproduction or survival, 
let alone have impacts on annual rates of recruitment or survival of 
this stock. Additionally, no mortality or Level A harassment is 
anticipated or authorized for the Eastern North Pacific Southern 
Resident stock of killer whales.
    In reference to the ``small numbers'' determination mentioned by 
the commenter, this determination does not apply to military readiness 
activities, including the Navy's activities in the NWTT Study Area. The 
National Defense Authorization Act for Fiscal Year 2004 amended section 
101(a)(5) of the MMPA for military readiness activities to remove the 
``small numbers'' and ``specified geographical region'' provisions, as 
well as amending the definition of ``harassment'' as applied to a 
``military readiness activity.''
    Comment 75: A commenter stated that in the 2019 Southern Resident 
Orca Task Force ``Final Report and Recommendations,'' the Task Force 
noted that ``the final decisions on training and testing activities 
conducted in the NWTT Study Area between November 2020 and November 
2027 should eliminate impacts from current, new or additional exercises 
involving mid-frequency sonar, explosives and other activities with the 
potential to adversely affect Southern Resident killer whale recovery 
or incorporate enhanced mitigation measures to reduce impacts.'' The 
commenter asserted that the proposed incidental takes clearly conflict 
with recommendations from the Southern Resident Orca Task Force.
    Response: NMFS and the Navy are aware of (and NMFS participated on) 
the 2019 Southern Resident Orca Task Force. See Comment 74 for 
information on mitigation measures, including measures added since 
publication of the proposed rule, that will reduce the number and/or 
intensity of expected incidental takes of Southern Resident killer 
whales. NMFS and the Navy have worked hard to put in place mitigation 
measures to ensure as much as possible that any relatively minor, 
short-term impacts that may occur will not affect that individual's 
reproduction or survival and are also practicable (i.e., allow the Navy 
to meet its statutorily required mission along with ensuring Navy 
personnel safety). See Comment 74 also for discussion of the effects of 
the remaining expected incidental takes on Southern Resident killer 
whales that cannot be avoided. With the additional mitigation measures, 
NMFS has ``eliminate[d] impacts . . . with the potential to adversely 
affect Southern Resident [killer whale] recovery'' and ``incorporate[d] 
enhanced mitigation measures to reduce impacts.''
    Comment 76: Multiple commenters stated that NMFS and the Navy must 
consider the highly endangered status and continuing decline of the 
endangered Southern Resident killer whale. The commenter stated that

[[Page 72364]]

NMFS must also recognize the threat of population level effects and 
greater than negligible impact from harm to individual killer whales. 
Another commenter stated that Level B harassment by Navy activities 
that interfere with feeding or displace killer whales from preferred 
foraging areas should be of significant concern, and that this cannot 
possibly constitute ``negligible impact'' to an already vulnerable 
population. Finally, a commenter noted that, given the imperiled nature 
of Southern Resident killer whales, the number of proposed takes 
threatens a significant impact on the population from the Navy's 
training and testing activities.
    Response: NMFS has carefully considered the status of Southern 
Resident killer whales in its analysis, as discussed in the Description 
of Marine Mammals and Their Habitat in the Area of the Specified 
Activities sections of the proposed and final rules and the Analysis 
and Negligible Impact Determination section of this final rule. 
Additionally, this final rule includes significant mitigation, as 
described in the response to Comment 74, and further in the Mitigation 
Measures section of this final rule, including additional mitigation 
added since publication of the proposed rule, to minimize impacts to 
marine mammals, with an emphasis on further reducing both the amount 
and severity of any take of Southern Resident killer whales.
    As also discussed in the response to Comment 74, NMFS' analysis 
indicates that either 51 individual whales are exposed above the 
behavioral harassment threshold (or in two of the 51 cases, above the 
TTS threshold) on one day within a year, or some fewer number of 
individuals might be exposed on two or three days (but no more than 51 
total exposure days, so for example, 25 individuals exposed on two days 
each within a year). Also, modeling supports the prediction that, given 
the movement of the animals and the characteristics of the testing and 
training, the duration of any exposure is expected to be relatively 
short, not more than seconds or minutes, or occasionally hours. As 
noted in the Analysis and Negligible Impact Determination section of 
this final rule, even acknowledging the small and declining stock size 
of the Southern Resident DPS of killer whales (which is the the MMPA 
Eastern North Pacific Southern Resident stock), this low magnitude and 
severity of harassment effects is unlikely to result in impacts on 
individual reproduction or survival, let alone have impacts on annual 
rates of recruitment or survival of this stock. Additionally, no 
mortality or Level A harassment is anticipated or authorized for the 
Eastern North Pacific Southern Resident stock of killer whales.
    Comment 77: A commenter noted that, according to the Navy's 
analysis, the Washington Inland Waters population of harbor porpoises 
and the Hood Canal population of harbor seals will be subjected to some 
of the highest estimated take, strongly suggesting that some activities 
with the potential to harm killer whales are concentrated in the Salish 
Sea and the interior waters of Puget Sound. The proposed activities 
overlap with areas of proposed critical habitat that NMFS itself 
recognizes as a ``high-use foraging area'' for Southern Resident killer 
whales. Another commenter stated that the lack of sensitivity to the 
Southern Resident killer whales' dwindling population and its need for 
a protected home in accordance with its endangered species status in 
2005 remains a critical concern. The commenter stated that in a perfect 
world, training should be excluded from their critical habitat. Another 
commenter stated that the Navy should identify high-use areas in both 
inland and offshore killer whale habitat for seasonal or permanent 
closures to NWTT activities to minimize overlap with Southern Resident 
killer whales.
    Response: NMFS fully considered the status of Southern Resident 
killer whales in its analysis, as discussed in the Description of 
Marine Mammals and Their Habitat in the Area of the Specified 
Activities sections of the proposed and final rules and the Analysis 
and Negligible Impact Determination section of this final rule. 
Potential impacts to marine mammals from acoustic and explosive 
sources, which are part of the Navy's planned activities in the NWTT 
Study Area, are analyzed in the Potential Effects of Specified 
Activities on Marine Mammals and their Habitat and Analysis and 
Negligible Impact Determination sections of the proposed and final 
rules, and in Section 3.4.2.1 and Section 3.4.2.2, of the 2020 NWTT 
FSEIS/OEIS, respectively. These effects analyses considered multiple 
factors, such as seasonal Southern Resident killer whale's abundance 
across the Study Area and the type, amount, and location of planned 
Navy activities.
    A greater number of incidental takes are estimated for harbor 
porpoises and harbor seals in comparison to other species, including 
Southern Resident killer whales, due to their much higher abundances in 
the Study Area. Additionally, the impacts to harbor porpoises and 
harbor seals in the Inland Waters occur in areas where Southern 
Resident killer whales do not. The majority of locations where the Navy 
conducts training and testing in the Inland Waters do not overlap with 
areas where Southern Resident killer whales occur. For instance, most 
testing occurs in Hood Canal (Dabob Bay) and at Keyport; Southern 
Resident killer whales are not present in either location. There has 
not been a sighting of Southern Resident killer whales in Hood Canal 
since 1995 (25 years ago). The locations where there is potential 
overlap of training and Southern Resident killer whale habitat include 
Everett, Crescent Harbor, and Navy OPAREA 3 and Navy OPAREA 7.
    As it did for all marine mammals, NMFS worked with the Navy during 
the MMPA rulemaking process to enhance mitigation measures for Southern 
Resident killer whales (i.e., the MMPA Eastern North Pacific Southern 
Resident stock) to ensure the least practicable adverse impact on the 
stock. As described in the Mitigation Measures section, this final rule 
includes additional mitigation in the Puget Sound and Strait of Juan de 
Fuca Mitigation Area, which includes the full extent of NWTT Inland 
Waters and overlaps with existing ESA Southern Resident killer whale 
critical habitat, designed to further avoid or reduce potential impacts 
on Southern Resident killer whales. New mitigation in this area 
includes a requirement for the Navy to use the lowest active sonar 
source levels practical to successfully accomplish each event, a 
prohibition on the use of explosives during testing, and seasonal 
awareness messages regarding the possible presence of concentrations of 
Southern Resident killer whales and gray whales, among other new 
measures, as described in the Assessment of Mitigation Measures for 
NWTT Study Area section of this final rule and in Appendix K 
(Geographic Mitigation Assessment) of the 2020 NWTT FSEIS/OEIS.
    The commenter also referenced proposed critical habitat for 
Southern Resident killer whales in inland waters; however, NMFS notes 
that the proposed ESA Southern Resident killer whale critical habitat 
is in offshore waters, rather than in the Salish Sea and Puget Sound. 
This final rule includes additional mitigation that overlaps with the 
proposed ESA Southern Resident killer whale critical habitat, including 
in the Marine Species Coastal Mitigation Area and the Olympic Coast 
National Marine Sanctuary Mitigation Area.
    Comment 78: Commenters stated that NMFS should analyze the 
cumulative impacts over the full extent of training and testing 
activities that would be

[[Page 72365]]

authorized by this permit, and one commenter noted that the Navy's 
testing and training activities have already been authorized twice 
before, and are likely to continue into the future. A commenter stated 
that killer whales are long-lived and it is likely that the same 
individuals would be affected in multiple years. This level of ongoing, 
perpetual take (68 percent, as one commenter noted) to specific 
individuals in a small population is a significant threat, commenters 
assert, that could result in displacement or physical harm over 
extended periods of time, and should be more clearly factored into the 
analysis impact. Further, one commenter asserted that instances of 
temporary hearing loss, such as the TTS contemplated in NMFS' 
authorization, can be cumulative and lead to long-term hearing loss. 
Commenters stated that NMFS and the Navy must also consider that 
harassment and behavioral impacts are likely to have a compounded 
effect on individuals that are already in compromised condition. 
Research currently being compiled into a health database for the 
Southern Resident killer whale community shows multiple individuals 
have been seen in poor body condition, and compared to Northern 
Resident killer whales, the Southern Resident population has lower 
survival and reproductive rates. The commenters asserted that given the 
many stresses already faced by this endangered population, ongoing, 
repeated, and cumulative impacts from NWTT activities could place 
additional stress on both individuals already in poor health, perhaps 
even leading to mortality, as well as on the population as a whole. 
Commenters asserted that NMFS has thus failed to show that these 
impacts are negligible under the MMPA.
    Response: NMFS has analyzed the cumulative impacts of the Navy's 
training and testing activities over the full seven-year extent of the 
regulations. Further, NMFS has fully considered the status of Southern 
Resident DPS killer whale (which is the same as the Eastern North 
Pacific Southern Resident stock under the MMPA) and the compromised 
health of some of the individuals of that stock in its analysis and 
negligible impact determination, as described in the Analysis and 
Negligible Impact Determination section of this final rule. No 
mortality or Level A harassment is anticipated or authorized for the 
Southern Resident DPS of killer whales. The 51 takes of Southern 
Resident killer whales, only two of which are estimated to involve TTS, 
each represent a day in which one individual whale is predicted to be 
exposed above the behavioral harassment threshold, which is described 
in detail in the Analysis and Negligible Impact Determination section 
of this final rule as well as the Navy's 2017 Criteria and Thresholds 
for U.S. Navy Acoustic and Explosive Effects Analysis (Phase III) 
report. This means that either 51 individual whales are exposed above 
this threshold on one day within a year, or some fewer number of 
individuals might be exposed on two or three days (but no more than 51 
total exposure days so, for example, 25 individuals exposed on two days 
each within a year and one individual exposed on one day). Also, 
modeling supports the prediction that, given the movement of the 
animals and the characteristics of the testing and training activities, 
the duration of any exposure is expected to be relatively short, not 
more than minutes, or occasionally hours. Even if these impacts 
occurred to an individual of compromised health, the behavioral impacts 
would not be expected to impact reproduction or health, much less 
result in a mortality, given the low severity and duration of effect 
that any individual killer whale is expected to experience within a 
year. Similarly, while significant repeated exposure to noise levels 
associated with TTS could, in certain circumstances (e.g., numerous 
exposures, long durations, with no time for recovery in between 
exposures) lead to PTS, there is no reason to expect that the number 
(no more than a single instance of TTS to either of the two individuals 
taken within a year) and nature (low level) of the exposures 
anticipated from Navy training and testing activities would lead to PTS 
for Southern Resident killer whales.
    Further, as discussed in detail in the Mitigation Measures section 
of this rule and the response to Comment 74, this rule includes 
extensive mitigation for Southern Resident killer whales that will 
reduce both the probability and severity of impacts to this stock, 
including additional measures that have been added since the proposed 
rule. Even acknowledging the small and declining stock size of the 
Southern Resident DPS of killer whales, the low magnitude and severity 
of effects is unlikely to result in impacts on individual reproduction 
or survival, let alone have impacts on annual rates of recruitment or 
survival of this stock. Further, given the absence of any expected 
impacts on individual fitness or annual rates of recruitment or 
survival, there is no possibility that the impacts of the authorized 
take could accrue over the seven-year period of the rule in a manner 
that could exceed a negligible impact. Last, we note that the MMPA does 
not prohibit the authorization of incidental take for activities that 
continue in an area, as long as the necessary findings have been made 
within the period of the requested authorization.
    Comment 79: A commenter stated that the proposed Navy activities do 
not account for the Southern Resident killer whales' seasonal 
behaviors. Another commenter stated that additional mitigation and 
avoidance measures should include establishing seasonal limitations on 
the use of sonars in traditional Southern Resident killer whale 
foraging areas.
    Response: Seasonal behaviors and locations of marine mammals, 
including Southern Resident killer whales, were accounted for in both 
the effects analysis (e.g., density estimate input into the modeling of 
take) and in consideration and inclusion of mitigation measures (e.g., 
geographic mitigation measures targeted at protecting Southern Resident 
killer whales) in the NWTT Study Area. This final rule includes 
extensive mitigation for Southern Resident killer whales, including 
mitigation that is seasonally applicable, such as required seasonal 
awareness notification messages that the Navy will issue for the Puget 
Sound and Strait of Juan de Fuca Mitigation Area and the Marine Species 
Coastal Mitigation Area during times when Southern Resident killer 
whales and gray whales may be present in the area in higher 
concentrations. The rule includes seasonal restrictions on explosive 
Mine Countermeasure and Neutralization Testing in the Marine Species 
Coastal Mitigation Area. This final rule also includes mitigation areas 
in which mitigation requirements limit or prohibit the use of sonar 
during certain activities. Seasonal and year-round mitigation measures, 
including those that have been added since publication of the proposed 
rule, and their benefits to marine mammals (including Southern Resident 
killer whales specifically) are discussed further in the response to 
Comment 74 and the Mitigation Measures section of this final rule, as 
well as Appendix K (Geographic Mitigation Assessment) of the 2020 NWTT 
FSEIS/OEIS.
    Comment 80: A commenter stated that increasing the Navy's testing 
and training activities at this time is counter to what the endangered 
Southern Resident killer whales need to have a chance at recovery. 
Without bold and immediate actions, the Southern Resident killer whales 
are likely to go extinct. The commenter stated that

[[Page 72366]]

everything that can be done now to protect the Southern Resident killer 
whales is critical. Despite being listed under the ESA for nearly 15 
years, this unique population is not recovering and is continuing to 
decline. The commenter further stated that it is obvious that status 
quo actions, including the Navy's training and testing activities, are 
not serving the Southern Resident killer whales. In a time when 
everyone should be acting to address and decrease threats facing the 
population, including reducing noise and disturbance, the Navy's 
proposed activities increase the risks from ocean noise, vessel strikes 
and disturbance, potential direct harm and injury to Southern Resident 
killer whales, and displacement from preferred habitat. The commenter 
stated that given the Southern Resident killer whale's highly 
endangered status and continuing decline, the Navy should adjust its 
training and testing activities to reduce impacts and increase 
protections for these iconic animals.
    Response: The Navy has conducted active sonar training and testing 
activities in the NWTT Study Area for decades, and there is no evidence 
that routine Navy training and testing has negatively impacted Southern 
Resident killer whale populations in the Study Area. Based on the best 
available science summarized in the 2020 NWTT FSEIS/OEIS Section 
3.4.3.4 (Summary of Monitoring and Observations During Navy Activities 
Since 2015), long-term consequences for Southern Resident killer 
whales, including for the seven-year period of this rule, are unlikely 
to result from Navy training and testing activities in the Study Area.
    As discussed in the Mitigation Measures section of this final rule, 
elsewhere in this section, and in Chapter 5 (Mitigation) of the 2020 
NWTT FSEIS/OEIS, the Navy will implement extensive mitigation to avoid 
or reduce potential impacts from the NWTT activities on Southern 
Resident killer whales. These mitigation measures include mitigation 
areas that restrict certain activities in places and during times that 
are particularly important to Southern Resident killer whales (and 
other marine mammals). One of these mitigation areas, the Puget Sound 
and Strait of Juan de Fuca Mitigation Area, encompasses the entire 
extent of NWTT Inland Waters, including Southern Resident killer whale 
ESA-designated critical habitat. New mitigation measures in the Puget 
Sound and Strait of Juan de Fuca Mitigation Area will result in 
training and testing activities being conducted in NWTT Inland Waters 
only when necessitated by mission-essential training or testing program 
requirements. With implementation of the new mitigation measures 
included in this final rule, we do not anticipate any take of Southern 
Resident killer whales in NWTT Inland Waters due to NWTT training and 
testing activities. This final rule also includes additional mitigation 
measures for Southern Resident killer whales in other mitigation areas, 
including the Marine Species Coastal Mitigation Area and the Olympic 
Coast National Marine Sanctuary Mitigation Area. Please refer to the 
Mitigation Measures section of this final rule for further discussion 
of the required mitigation measures in the NWTT Study Area.
    Additionally, NMFS considered the status of Southern Resident 
killer whales in its analysis, as discussed in the Analysis and 
Negligible Impact Determination section of this final rule. Modeling 
supports NMFS' conclusion that, given the movement of the animals and 
the characteristics of the testing and training, the duration of any 
exposure of a Southern Resident killer whale is expected to be 
relatively short, not more than minutes, or occasionally hours. As 
noted in the Analysis and Negligible Impact Determination section and 
the response to Comment 78, even acknowledging the small and declining 
stock size of Southern Resident killer whales, this low magnitude and 
severity of harassment effects is unlikely to result in impacts on 
individual reproduction or survival, let alone have impacts on annual 
rates of recruitment or survival of this stock. Additionally, no 
mortality or Level A harassment is anticipated or authorized for the 
Eastern North Pacific Southern Resident stock.
    Comment 81: A commenter stated that with the apparent loss of three 
whales last summer, Southern Resident killer whales appear to have a 
population of just 73 whales--the lowest population size in more than 
40 years. Given this declining population, the loss of even one more 
whale could greatly undermine recovery efforts for decades. The 
commenter stated that NMFS does not consider the most up-to-date 
information on the Southern Resident killer whale population. The 
commenter stated that while NMFS purports to rely on the ``best 
available science'' in developing stock numbers, NMFS actually assesses 
impacts based on a potentially outdated population size of 75, and does 
not note the data indicating the population may sit at just 73 whales. 
As a result, NMFS fails to ensure its reliance on the best and most-up-
to-date scientific information, which could result in NMFS 
underestimating the harm of the Navy's activities on this vulnerable 
population. With such a small and shrinking population, the impact of 
each take is amplified within the population.
    Response: NFMS relied on the 2019 Stock Assessment Reports 
(published in August 2020) for the latest abundance information for all 
stocks, except the inland water stocks of harbor seals, as the stock 
assessments are outdated and did not reflect the best available 
science, as described in this final rule. The 2019 Southern Resident 
killer whale stock assessment indicates that the minimum population 
estimate (Nmin) for the Eastern North Pacific Southern Resident stock 
of killer whales is 75 animals. The stock assessment indicates that 
this estimate serves as both the Nmin, as well as the best estimate of 
abundance because the assessment is a ``direct count of individually 
identifiable animals [and] it is thought that the entire population is 
censused every year.'' Therefore, NMFS based its analysis on this 
population estimate, as it reflects the best available science given 
that it is the most recent, peer-reviewed literature that NMFS is aware 
of. Separately, we note that two calves have been born in 2020 (Orca 
Network, 2020) and are not included in the 2019 SAR.
    Comment 82: A commenter stated that additional datasets are 
available for killer whale response to noise. For example, in Bain and 
Dahlheim's (1994) study of captive killer whales exposed to band-
limited white noise in a band similar to that of mid-frequency sonar at 
a received level of 135 dB re 1uPa, abnormal behavior was observed in 
50 percent of the individuals. This is far lower than the level 
observed in bottlenose dolphins. In addition, Bain (1995) observed that 
100 percent of wild killer whales appeared to avoid noise produced by 
banging on pipes (fundamental at 300 Hz with higher harmonics) to 135 
dB re 1uPa contour. This indicates the difference between wild and 
captive killer whales (non-zero risk in captive marine mammals might 
correspond to 100 percent risk in wild individuals of the same 
species), as well as implying that risk of 100 percent may occur by 135 
dB re 1uPa for this genus in the wild. The commenter stated that while 
more emphasis needs to be placed on the captive-wild difference, there 
are also species differences, like Dall's porpoises, harbor seals, and 
California sea lions being relatively noise tolerant, and harbor 
porpoises, killer whales, and Steller sea lions being relatively noise 
intolerant.
    The commenter stated further that killer whales responded to vessel 
traffic at around 105-110 dB with conspicuous

[[Page 72367]]

behavioral changes such as increased rates of threat displays and 
evasive swimming patterns, although the commenter provided no 
scientific source for this assertion. The commenter stated that subtle 
behavioral changes, such as inhibition of foraging behavior, were 
observed at lower levels. While inhibition of foraging is a Level B 
take, in a food limited population, inhibition of foraging is likely to 
result in increased mortality and/or reduced recruitment.
    Response: It is clear in some parts of their comment that the 
commenter is referring to the Phase I and II behavioral criteria, i.e., 
criteria that we used in previous rules and not this one, and therefore 
some of the comment is inapplicable. In this rule, NMFS and the Navy 
have incorporated emergent best available science into new BRFs for 
Phase III, and this rule specifically, that are described in the 
technical report titled Criteria and Thresholds for U.S. Navy Acoustic 
and Explosive Effects Analysis (Phase III) (U.S. Department of the 
Navy, 2017a) available at www.nwtteis.com, including data on exposures 
to wild killer whales.
    The Phase III behavioral criteria appropriately incorporate data 
from behavioral response studies that were designed to record 
behavioral observations and contained detailed data on reactions at 
specific received sound levels. Specifically, data needed to meet both 
of the following criteria to be used in the quantitative derivation: 
(1) Observations of individual/group animal behavior were related to 
known or estimable received levels, and (2) The study was primarily 
designed to observe behavioral changes during controlled exposures or 
actual Navy activities (i.e., monitoring). The data referenced in this 
comment (Bain, 1995 and Bain and Dahlheim, 1994) were not specifically 
included in the criteria because they do not meet either of these two 
criteria for BRF inclusion and, further, we note that the sound source 
referenced is a notably lower frequency than the majority of the Navy's 
sources used for training and testing, and the signal would be 
characterized as an impulse, rather than non-pulse like active sonar 
is. The best available science is documented in the technical report 
referenced above and Section 3.4.2.1.1.5 (Behavioral Reactions) of the 
2020 NWTT FSEIS/OEIS. Nonetheless, the BRFs used in the final rule 
predict that close to 20 percent of odontocetes exposed to received 
levels of 135dB will respond in a manner that would qualify as a take, 
so the data presented by the commenter is not at odds with the criteria 
used here. As shown in the technical report, the Navy considered how 
captive and wild animals may respond differently to acoustic stressors 
when analyzing response severity. NMFS has carefully reviewed the 
Navy's criteria, i.e., BRFs and cutoff distances for these species, and 
agrees that they are the best available science and the appropriate 
method to use at this time for determining impacts to marine mammals 
from sonar and other transducers and for calculating take and to 
support the determinations made in this rule.
    NMFS explained in the response to Comment 38 why responses to 
vessel noise alone are unlikely to qualify as Level B harassment and 
further described that Navy vessels are also much quieter than typical 
vessels because they are designed that way to evade detection by 
adversaries.
    Comment 83: A commenter stated that the Navy's characterization of 
the killer whale dataset [used in the behavioral harassment thresholds] 
is incorrect. The commenter stated that the Navy indicates the effects 
observed in the presence of mid-frequency sonar in Haro Strait were 
confounded by the presence of vessels. However, the effects of vessels 
on killer whales have been extensively studied, both prior to and 
subsequent to exposure. The commenter asserted that behavioral 
responses attributed to mid-frequency sonar are qualitatively different 
than those observed to vessels alone. The commenter further stated that 
while the observations were based on a small sample, they were not 
inconsistent. The sonar signal was blocked from reaching the whales 
with full intensity by shallow banks or land masses during three 
segments of the observation period. The commenter said that the 
``inconsistencies'' can be attributed to differences in behavior 
depending on whether there was a direct sound path from the USS Shoup 
(the vessel emitting sonar in the vicinity) to the whales. The 
commenter stated that there was extensive study of this population 
prior to exposure, as well as extensive post-exposure monitoring.
    The commenter also stated that the Navy incorrectly concludes that 
additional datasets are unavailable. In addition to the three data sets 
the Navy relies upon; captive cetaceans, killer whales, and right 
whales, they suggest that the data set illustrating the use of acoustic 
harassment and acoustic deterrent devices on harbor porpoises 
illustrates exclusion from foraging habitat. Data are also available 
showing exclusion of killer whales from foraging habitat, although 
additional analysis would be required to assess received levels 
involved. The devices which excluded both killer whales and harbor 
porpoises had a source level of 195 dB re 1[mu]Pa, a fundamental 
frequency of 10 kHz, and were pulsed repeatedly for a period of about 
2.5 seconds, followed by a period of silence of similar duration, 
before being repeated. Devices used only with harbor porpoises had a 
source level of 120-145 dB re 1[mu]Pa, fundamental frequency of 10 kHz, 
a duration on the order of 300 msec, and were repeated every few 
seconds. Harbor porpoises, which the Navy treats as having a B+K value 
of 120 dB re 1[mu]Pa (with A large enough to yield a step function) in 
the Atlantic Fleet Active Sonar Training (AFAST) DEIS, 45 dB lower than 
the average value used in the Hawaii Range Complex (HRC) SDEIS, may be 
representative of how the majority of cetacean species, which are shy 
around vessels and hence poorly known, would respond to mid-frequency 
sonar. Even if harbor porpoises were given equal weight with the three 
species used to calculate B+K, including them in the average would put 
the average value at 154 dB re 1[mu]Pa instead of 165 dB re 1[mu]Pa.
    Response: Regarding the datasets used to develop behavioral 
criteria, the commenter is referring to the Phase I and II behavioral 
criteria, i.e., criteria that we used in previous rules and not this 
one, and therefore much of the comment is inapplicable. In this rule, 
NMFS and the Navy incorporated emergent best available science into new 
BRFs that are described in the technical report titled Criteria and 
Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase 
III) (U.S. Department of the Navy, 2017a), available at 
www.nwtteis.com.
    Regarding the Haro Strait data, in May 2003, killer whales in Haro 
Strait, Washington, exhibited what were believed by some observers to 
be aberrant behaviors, during which time the USS Shoup was in the 
vicinity and engaged in mid-frequency active sonar operations. Sound 
fields modeled for the USS Shoup transmissions (Fromm, 2009; National 
Marine Fisheries Service, 2005; U.S. Department of the Navy, 2004) 
estimated a mean received SPL of approximately 169 dB re 1 [micro]Pa at 
the location of the killer whales at the closest point of approach 
between the animals and the vessel (estimated SPLs ranged from 150 to 
180 dB re 1 [micro]Pa). However, attributing the observed behaviors 
during that particular exposure to any one cause is problematic given 
there were six nearby whale watch vessels surrounding the pod, and 
subsequent research has demonstrated that ``Southern Residents

[[Page 72368]]

modify their behavior by increasing surface activity (breaches, tail 
slaps, and pectoral fin slaps) and swimming in more erratic paths when 
vessels are close'' (National Oceanic and Atmospheric Administration, 
NOAA Fisheries, 2014). Data from this study were not used in the Phase 
III BRFs because they did not meet the criteria to be used in the 
quantitative derivation (see response to Comment 82 for description of 
criteria). Nonetheless, the BRFs used in this 2020-2027 NWTT rule 
indicate a likelihood of approximately 30 to 95 percent that the 
estimated received levels during this exposure would be associated with 
Level B harassment by behavioral disturbance.
    Regarding the harbor porpoise data, the data referenced in this 
comment was a study of acoustic harassment devices and do not meet 
either criteria for BRF inclusion. Further, NMFS and the Navy continue 
to use a behavioral harassment threshold for harbor porpoises that 
predicts that 100 percent of harbor porpoises exposed at levels above 
120 dB will respond in a manner that qualifies as Level B harassment, 
which encompasses the results the commenter references. However, we 
disagree that harbor porpoise data should be combined with other 
odontocete data to create one behavioral harassment threshold for 
odontocetes, given the extensive literature documenting the heightened 
sensitivity of harbor porpoises to sound. The best available science is 
documented in Criteria and Thresholds for U.S. Navy Acoustic and 
Explosive Effects Analysis (Phase III) (U.S. Department of the Navy, 
2017a), available at www.nwtteis.com, and Section 3.4.2.1.1.5 
(Behavioral Reactions) of the 2020 NWTT FSEIS/OEIS.
    Comment 84: A commenter stated that NMFS should address problems in 
the proposed rule, which the commenter asserts underestimate and 
discount potential take of Southern Resident killer whales, and 
reconsider its negligible impact determination for the population. The 
commenter asserted that NMFS' conclusory statement that the Navy's 
activities are ``unlikely to result in impacts on individual 
reproduction or survival'' or cause greater than negligible impacts on 
the Southern Resident killer whale population is arbitrary and 
capricious. The commenter stated that conclusion is based in part on 
the premise that the Navy would cause as many as 51 Southern Resident 
killer whale takes each year, a number that, like the Navy's original 
calculation of two annual takes, makes little sense given that the 
whales travel together in pods, making it far more likely that every 
member of the pod would be affected. Nor does it make sense that take 
estimates for Washington Inland Waters harbor porpoises and Hood Canal 
harbor seals would number in the hundreds of thousands, while Southern 
Resident killer whale takes account for a handful. The commenter argued 
that the agency has provided little rationale for why the abandonment 
or significant alteration in vital activities that these take numbers 
represent would have a negligible impact on Southern Resident killer 
whales, given the low vital rates that currently prevail in this 
endangered, declining population.
    In addition, the commenter stated that although some form of 
command approval is required before mid-frequency sonar is used in the 
Salish Sea, this requirement does little to ensure that such activities 
do not occur. The commenter also stated that NMFS has grossly 
overstated the effectiveness of the Navy's mitigation in preventing 
mortalities.
    The commenter additionally states that mitigation areas for 
Southern Resident killer whales fail to include the whales' offshore 
habitat, where most of the agency's estimated takes are expected to 
occur.
    Response: The basis for NMFS' conclusions about the effects of the 
estimated, and now authorized, Level B harassment takes of Southern 
Resident killer whales, both on affected individuals and on the stock's 
annual rates of recruitment and survival, has been fully and carefully 
explained in the proposed rule and again in this final rule. The Navy 
consulted with Southern Resident killer whale experts in the 
development of the density layers used for modeling and the acoustic 
modeling process used in this rule accounts for the population 
occurring in 3 large pods, composed of the appropriate individual 
numbers of killer whales. However, despite occurring in pods, not all 
animals exposed to similar sound levels will respond in the exact same 
manner. The BRFs take into account individual responses, and were 
developed from data that included real exposures of wild killer whales 
to Naval sonar sources. Further, Navy training and testing activities 
predominantly occur in portions of the NWTT Study Area inland waters 
where Southern Resident killer whales rarely occur (e.g., Hood Canal, 
Dabob Bay, Bremerton, and Keyport). Also, the density is low overall 
for Southern Resident killer whales, so it is much less likely that a 
pod will be encountered. Also while Southern Resident killer whales 
travel in pods, individuals are spread out over a fairly large area and 
while more than one individual might be taken sometimes if a Navy 
activity is encountered, it is far less likely that an entire pod would 
be exposed at levels resulting in take. Please refer to the response to 
Comment 74 for further discussion of the implication of the 51 
authorized takes of Southern Resident killer whales.
    We also note that the commenter is incorrect that the mitigation 
areas in the rule fail to include the whale's offshore habitat. The 
proposed included mitigation that overlaps with the proposed ESA 
Southern Resident killer whale critical habitat (in offshore waters), 
including in the Marine Species Coastal Mitigation Area and the Olympic 
Coast National Marine Sanctuary Mitigation Area, and the mitigation in 
those areas has been expanded in the final rule. Please see the 
Mitigation Measures section for a full description of the mitigation 
required in these areas.
    Regarding the idea that NMFS has grossly overstated the 
effectiveness of the Navy's mitigation in preventing mortalities, we 
note that no mortality was modeled, even without consideration of 
mitigation. Nonetheless, this final rule includes extensive mitigation 
for Southern Resident killer whales as discussed in the Mitigation 
Measures section and in the response to Comment 74. Please refer to the 
Mitigation Measures section of this final rule for a full discussion.
    Regarding Command authority, requirements for naval units to obtain 
approval from the appropriate designated Command authority prior to 
conducting active sonar pierside maintenance or testing with hull-
mounted mid-frequency active sonar will elevate the situational and 
environmental awareness of respective Command authorities during the 
event planning process. Requiring designated Command authority approval 
provides an increased level of assurance that mid-frequency active 
sonar is a required element for each event. Such authorizations are 
typically based on the unique characteristics of the area from a 
military readiness perspective, taking into account the importance of 
the area for marine species and the need to mitigate potential impacts 
on Southern Resident killer whales (and other marine mammals, such as 
gray whales) to the maximum extent practicable. Additionally, the Navy 
has reported to NMFS that, where included in past NWTT authorizations, 
the requirement for Navy personnel to gain permission from the 
appropriate command

[[Page 72369]]

authority to conduct activities in a particular mitigation area has 
resulted in the activities not being conducted in the designated 
mitigation areas.
    Please refer to Comment 77 for a full explanation of the higher 
take numbers for Washington Inland Waters harbor porpoises and Hood 
Canal harbor seals in comparison to Southern Resident killer whales.

Other Comments

    Comment 85: A commenter questioned how many incidental injuries and 
deaths would it take before NOAA and the Navy recognize the dire 
situation in which they are putting marine mammals. The commenter 
further questioned what would it take for NOAA to decline the Navy's 
request for yet another permit in which hundreds and thousands of 
animals are slated to be hurt or die.
    Response: Through the MMPA, Congress has determined that an 
applicant, including a federal agency like the Navy, can request and 
receive marine mammal incidental take authorization provided all 
statutory findings are made (and all other legal requirements are met). 
For the Navy's application, NMFS has determined, among other things, 
that the estimated take will have a negligible impact on each of the 
affected species or stocks and has included the required mitigation, 
monitoring, and reporting measures. Therefore it is appropriate to 
authorize the incidental take. As discussed elsewhere in this section 
and the Mitigation Measures section of the rule, the final rule 
includes extensive mitigation measures to reduce impacts to the least 
practicable level. We note that the commenter overstates the scale of 
authorized injury and mortality and, further, that the rule includes a 
robust suite of mitigation measures to lessen the probability and 
severity of impacts on marine mammals.
    Comment 86: A commenter stated that the Navy is entitled to consult 
with the Office of National Marine Sanctuaries to gain access to 
National Marine Sanctuary waters, in this case the Olympic Coast 
National Marine Sanctuary. The commenter asserted that the authority to 
do so does not, however, justify its position in designing the NWTT 
Study Area to include an offshore portion of these waters. The meaning 
of the word ``sanctuary'' has been compromised beyond recognition by 
federal government agencies, but that does not mean the Navy should 
continue to disregard the intent of the government in establishing 
these waters to protect marine animal and plant life. The commenter 
stated that there are no circumstances under which it should be 
permissible to carry out military training exercises in a designated 
federal marine sanctuary. Another commenter stated that the Sanctuary 
would continue to be unacceptably damaged by the Navy's training 
activities and that the activities cited by the Navy would cause long-
term damage to the Sanctuary ecosystem which NOAA is supposed to 
protect as its administrator. Another commenter stated that the Navy 
needs to clear out of the Olympic Coast National Marine Sanctuary, 
permanently.
    Response: Regulations for the Olympic Coast National Marine 
Sanctuary at 15 CFR part 922, subpart O specifically address the 
conduct of Department of Defense military activities in the sanctuary, 
though we disagree with one commenter's suggestion that the Navy was 
intentionally targeting the Sanctuary. In addition, both NMFS and the 
Navy consulted with NOAA's Office of National Marine Sanctuaries under 
section 304(d) of the National Marine Sanctuaries Act regarding their 
actions that had the potential to injure sanctuary resources in the 
Olympic Coast National Marine Sanctuary. We disagree with the 
commenter's assertion that the Navy's activities will cause long-term 
damage to the Sanctuary ecosystem and refer the reader to the documents 
associated with the consultation, which may be found at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities. Comments about the 
Navy's activities generally in national marine sanctuaries are beyond 
the scope of this rule.
    Comment 87: A commenter stated that NMFS has a federal trust 
responsibility to Indian Tribes and therefore a heightened duty to 
apply the MMPA with special care and to protect and preserve marine 
species and areas of interest and concern for those Tribes to which the 
federal trust responsibility applies. Therefore, when faced with 
several alternatives for mitigation, for example, a commenter stated in 
a related comment that NMFS ``must choose the alternative that is in 
the best interests of the Indian tribe.''
    A commenter stated that the trust responsibility serves several 
purposes in this context. First, it requires NMFS to be especially 
cognizant of Tribes' needs as they pertain to their cultural ways of 
life and engage in meaningful government-to-government consultation 
concerning the proposed rule. Second, it requires NMFS to ensure that 
its application of the MMPA incidental take provisions avoids harm to 
Tribes' cultural ways of life, including subsistence, that are 
dependent upon culturally important species, places, and ecosystems and 
protects the species necessary for the Tribes' well-being and survival.
    The commenter stated that NMFS' obligation to Indian Tribes applies 
to all Tribes affected by the Navy's NWTT activities, including the ten 
federally recognized member Tribes of the InterTribal Sinkyone 
Wilderness Council, whose territories are situated within and offshore 
from Northern California and who maintain important cultural 
connections with their traditional coastal ecosystems and migrating 
marine mammals. The Sinkyone Council's member Tribes are: Cahto Tribe 
of Laytonville Rancheria; Coyote Valley Band of Pomo Indians; Hopland 
Band of Pomo Indians; Pinoleville Pomo Nation; Potter Valley Tribe; 
Redwood Valley Band of Pomo Indians; Robinson Rancheria of Pomo 
Indians; Round Valley Indian Tribes; Scotts Valley Band of Pomo 
Indians; and Sherwood Valley Rancheria of Pomo Indians. The commenter 
noted that the ten Northern California Tribes are in formal government-
to-government consultation with the Navy regarding Tribal opposition to 
the Navy's training and testing activities, and the NWTT's impacts to 
marine mammals and the Tribes' cultural ways of life.
    Response: NMFS is fully aware of and sensitive to its federal trust 
responsibilities to all Indian Tribes. Consistent with federal 
directives on consultation and coordination with Indian Tribal 
governments, NMFS has engaged in government-to-government discussions 
with the Northern California Tribes of the InterTribal Sinkyone 
Wilderness Council, and is discussing concerns directly with the member 
Tribes and Council staff. The Navy is also engaged in government-to-
government consultation with the 10 Northern California Tribes of the 
InterTribal Sinkyone Wilderness Council (as well as other Tribes) on 
its training and testing activities, including impacts on marine 
mammals.
    Also, as part of the MMPA rulemaking process, NMFS sought 
information on how the Navy's activities could affect Alaskan Natives' 
subsistence use in southeast Alaska. NMFS has added a mitigation 
measure in this final rule to minimize potential impacts on subsistence 
hunters from four Alaskan Native communities that are also federally 
recognized Tribes. See the Subsistence Harvest of Marine Mammals 
section for more information.

[[Page 72370]]

    Comment 88: A commenter stated that NMFS proposes to authorize take 
of multiple island-associated populations, most of unknown population 
size and many presumably with small or limited ranges. To justify the 
authorization notwithstanding the lack of robust mitigation measures, 
the commenter stated that the agency makes a number of assumptions that 
are not supported by the best available science.
    Response: This comment is not applicable to this rulemaking as 
there are no ``island-associated populations'' impacted by the Navy's 
NWTT activities or occurring within the NWTT Study Area.
    Comment 89: A commenter questioned whether any ethical 
considerations have gone into the issuance of these authorizations for 
the United States government to harass and injure marine mammals for 
the past 10 years, and another commenter referenced Occupational Safety 
and Health Administration standards for human noise exposure limits and 
suggested parallel ``pain thresholds'' for killer whales. The commenter 
asserted that although the MMPA requires mitigation strategies in order 
to authorize incidental takings, the Navy is violating this provision 
by requiring a constant authorization to operate in the same location. 
The commenter stated that the Navy's activities are never-ending and 
now the Navy asks for yet another seven-year extension of the same rule 
that will allow the Navy to test its sonar, explosives, and vessels in 
the same area of water that will impact the same populations of marine 
mammals that have been subjected to these same tests and disturbances 
for a decade. The commenter questioned how the Navy can continue to 
justify repeating their activities in the same location without 
producing any new results.
    The commenter stated that there appears to be no end to the Navy's 
testing and no end to the Navy's reluctance to unearth credible 
evidence of the facts surrounding the takings that have and will occur 
in the NWTT area. The commenter questioned the factual ground on which 
NMFS can now grant the Navy continued permission to cause injury and 
death to protected marine mammals. The commenter stated that in this 
circumstance, the Navy should be denied authorization because it has 
failed to show that past test activities do not provide a sufficient 
basis to achieve its military readiness. In the absence of such a 
showing, the Navy cannot credibly claim that it has pursued the least 
practical method. Another commenter noted that proximity to Naval bases 
for the convenience of sailors and their families, or interesting 
underwater topography taken as a rationale for continuing exercises 
does not warrant even one ``take'' of Southern Resident killer whales.
    Response: The MMPA provides for the authorization of incidental 
take caused by activities that will continue in an area. The law 
directs NMFS to process adequate and complete applications for 
incidental take authorization, and issue the authorization provided all 
statutory findings and requirements, as well as all associated legal 
requirements, are met. The MMPA does not require the Navy to prove 
anything regarding whether previous activities were sufficient for 
achieving military readiness, or to justify why they have located their 
activities where they have (except inasmuch as it is considered in the 
least practicable adverse impact analysis for geographic mitigation 
considerations). Likewise, section 101(a)(5)(A) of the MMPA does not 
include standards or determinations for the agency to consider the 
ethical and other factors raised by the commenters.
    As described in the rule, NMFS is required to evaluate the 
specified activity presented by the Navy in the context of the 
standards described in this final rule, and NMFS has described how 
these standards and requirements have been satisfied throughout this 
final rule.
    Both this rule and the prior rules for training and testing 
activities in the NWTT Study Area have required monitoring to report 
and help better understand the impacts of the Navy's activities on 
marine mammals. The Navy has conducted all monitoring as required, and 
the associated Monitoring Reports may be viewed at: https://www.navymarinespeciesmonitoring.us/reporting/pacific/.
    Comment 90: A commenter stated that the Navy provides no factual 
basis from which a rational determination can be made about species 
population and their geographical location. Indeed, the commenter 
asserts that it is pure speculation to conclude that any figure cited 
by the Navy is a ``small'' number of animals. However, one thing is 
certain according to the commenter. The Navy has had the opportunity 
and motivation to seek the needed information, and it has failed to do 
so. The commenter questioned how many incidental injuries and deaths it 
would take before the Navy's proposed activities were considered to be 
too great a loss for the animal species involved. In the absence of any 
credible facts, NMFS cannot make a rational determination that the 
Navy's activities will affect only a small number of any species and 
that the outcome of the activities will not adversely affect 
geographically diverse animal populations.
    Response: The ``small numbers'' determination discussed by the 
commenter does not apply to military readiness activities, including 
the Navy's activities in the NWTT Study Area. The National Defense 
Authorization Act for Fiscal Year 2004 amended section 101(a)(5) of the 
MMPA for military readiness activities to remove the ``small numbers'' 
and ``specified geographical region'' provisions, as well as amending 
the definition of ``harassment'' as applied to a ``military readiness 
activity.''
    Comment 91: A commenter stated that NMFS should operate in full 
transparency and good faith toward our fellow Washingtonians and reopen 
the comment period. The comment period should be, at least, 60 days 
with plenty of notice to the communities impacted, thus allowing them 
to give testimony. Please give proper notification to the public and to 
all who made comments on the May 29, 2019, Navy EIS. The Navy should be 
able to provide those names and addresses. The commenter specifically 
requested that NMFS include them on its list for notification for 
public comment. Another commenter stated that NMFS failed to notify the 
public and other governmental agencies regarding the authorization 
process. The lack of transparency has not allowed for NEPA-mandated 
public comment.
    Response: NMFS provided full notice to the public in the Federal 
Register on two opportunities to provide information and comments 
related to this rulemaking: The notice of receipt of the Navy's 
application for MMPA incidental take authorization (84 FR 38225, August 
6, 2019) and the notice of NMFS' proposed incidental take rule (85 FR 
33914, June 2, 2020). NMFS provided 30 and 45 days, respectively, for 
the public to comment and provide input on those documents. These 
notices and the associated comment periods satisfy the requirements of 
the MMPA and our implementing regulations. Further, interested persons 
also had the opportunity to comment through the NEPA process on, among 
other things, the Notice of Intent to Prepare a Supplemental 
Environmental Impact Statement for Northwest Training and Testing and 
the Notice of Availability of the NWTT Draft Supplemental Environmental 
Impact Statement/Overseas Environmental Impact Statement for both this 
MMPA

[[Page 72371]]

rulemaking and the Navy's activities. Given these opportunities for 
public input and the need to ensure that the MMPA rulemaking process 
was completed in the time needed to ensure coverage of the Navy's 
training and testing activities, NMFS determined that additional time 
for public comment was not possible. NMFS has practiced full and 
appropriate transparency under both the MMPA and NEPA.

Changes From the Proposed Rule to the Final Rule

    Between publication of the proposed rule and development of the 
final rule, the Navy has decreased their activity levels for some 
training activities. As a result, the annual and/or seven-year take 
estimates for some species have changed (all decreases with the 
exception of Kogia, which increased by 1 annually and over seven 
years). Additional mitigation measures have also been added, including 
the identification of a new mitigation area, additional requirements in 
existing areas, and new procedural measures. Additionally, harbor seal 
abundance estimates for inland water stocks have been refined.
    The Navy has reduced the number of planned Mine Neutralization-
Explosive Ordnance Disposal (EOD) (Bin E3) training events from 12 to 6 
annually, and 84 to 42 over the seven-year period of the rule. The Navy 
also reduced the number of Gunnery Exercise (Surface-to-Surface)- Ship 
(GUNEX [S-S]-Ship) training exercises from 90 to 34 annually, and 504 
to 238 over the seven-year period, counting only the explosive events, 
as noted in Table 3. Additionally, the Navy added bin HF1 to the 
Submarine Sonar Maintenance training activity. (This change does not 
increase total HF1 hours, but redistributes them to include use of the 
source types identified in bin HF1) Finally, the Navy clarified the 
number of planned Mine Countermeasure and Neutralization Testing events 
in the offshore area. The final rule reflects 2 events annually, and 6 
events over the seven-year period, as one of the 3 annual events noted 
in the proposed rule does not include acoustic components. This change 
resulted in decreases in estimated take over seven years for the 
following species: fin whale, sei whale, minke whale, humpback whale, 
gray whale, northern right whale dolphin, Pacific white-sided dolphin, 
Risso's dolphin, Kogia whales, Dall's porpoise, harbor porpoise, 
California sea lion, Steller sea lion, harbor seal, and northern 
elephant seal. Revised take estimates are reflected in Table 32 and 
Table 33. This change in activity also resulted in a reduction in HF4 
sonar hours associated with Mine Countermeasure and Neutralization 
testing; however, this reduction is not shown quantitatively.
    In addition, the take estimates for some species during both 
training and testing have been updated, and are reflected in Table 32 
(Training) and Table 33 (Testing). For all updated species except 
Kogia, the maximum annual take remained the same, but the seven-year 
total decreased. For Kogia Spp., takes during training activities 
decreased by 1 both annually, and over the seven-year period of the 
rule. During testing activities, annual takes by Level B harassment 
decreased by 1 and annual takes by Level A harassment increased by 1. 
Over the seven-year period of the rule, takes by Level B harassment 
during testing activities decreased by 1.
    Specifically regarding the harbor seal density estimates, since 
publication of the proposed rule, additional information and analyses 
have been used to refine the abundance estimate of the Washington 
Northern Inland Waters, Hood Canal, and Southern Puget Sound stocks of 
harbor seal. These changes are discussed in greater detail in the Group 
and Species-Specific Analyses section of this rule, and the updated 
abundance estimates are used in our analysis and negligible impact 
determination.
    Regarding the additional mitigation measures, a new mitigation 
area, the Juan de Fuca Eddy Marine Species Mitigation Area has been 
added. No mine countermeasure and neutralization testing will be 
conducted in this area, and the Navy will conduct no more than a total 
of 33 hours of surface ship hull-mounted MF1 mid-frequency active sonar 
during testing annually within 20 nmi from shore in the Marine Species 
Coastal Mitigation Area, in this new Juan de Fuca Eddy Marine Species 
Mitigation Area, and in the Olympic Coast National Marine Sanctuary 
Mitigation Area combined. Please see the Mitigation Areas section for 
additional information on the new Juan de Fuca Eddy Marine Species 
Mitigation Area.
    New mitigation requirements also have been added in the following 
mitigation areas: The Marine Species Coastal Mitigation Area, the 
Olympic Coast National Marine Sanctuary Mitigation Area, and the Puget 
Sound and Strait of Juan de Fuca Mitigation Area. The Mitigation Areas 
section describes the specific additions in these mitigation areas 
since publication of the proposed rule and discusses additional 
information about all of the mitigation area requirements.
    Additionally, new procedural mitigation requires the Navy to 
conduct Mine Countermeasures and Neutralization during daylight hours 
and in Beaufort sea state conditions of 3 or less.
    This final rule also includes new discussion of monitoring projects 
being conducted under the 2020-2027 rule. These planned projects 
include research on the offshore distribution of Southern Resident 
killer whales in the Pacific Northwest (ongoing and planned through 
2022), and characterizing the distribution of ESA-listed salmonids in 
the Pacific Northwest (ongoing and planned through 2022). Please see 
the Past and Current Monitoring in the NWTT Study Area section for 
additional details about these planned projects.
    Finally, NMFS has added information discussing the nature of 
subsistence activities by Alaskan Natives in the NWTT Study Area in the 
Subsistence Harvest of Marine Mammals section of this final rule. NMFS 
also added a requirement for the Navy to continue to notify the 
following Alaskan Native communities of Navy operations that involve 
restricting access in the Western Behm Canal at least 72 hours in 
advance through issuance of its Notices to Mariners to minimize 
potential impact on subsistence hunters: Central Council of the Tlingit 
and Haida Indian Tribes, Ketchikan Indian Corporation, Organized 
Village of Saxman, and Metlakatla Indian Community, Annette Island 
Reserve.

Description of Marine Mammals and Their Habitat in the Area of the 
Specified Activities

    Marine mammal species and their associated stocks that have the 
potential to occur in the NWTT Study Area are presented in Table 9. The 
Navy anticipates the take of individuals of 28 \3\ marine mammal 
species by Level A harassment and Level B harassment incidental to 
training and testing activities from the use of sonar and other 
transducers and in-water detonations. In addition, the Navy requested 
authorization for three takes of large whales by serious injury or 
mortality from vessel strikes over the seven-year period. Currently, 
the Southern Resident killer whale has critical habitat designated 
under the Endangered Species Act (ESA) in the NWTT Study Area 
(described below).

[[Page 72372]]

However, NMFS has recently published two proposed rules, proposing new 
or revised ESA-designated critical habitat for humpback whales (84 FR 
54354; October 9, 2019) and Southern Resident killer whales (84 FR 
49214; September 19, 2019).
---------------------------------------------------------------------------

    \3\ The total number of species was calculated by counting 
Mesoplodont beaked whales as one species for the reasons explained 
in the Baird's and Cuvier's beaked whales and Mesoplodon species 
(California/Oregon/Washington stocks) section. The proposed rule 
erroneously indicated anticipated take of individuals of 29 marine 
mammal species.
---------------------------------------------------------------------------

    The NWTT proposed rule included additional information about the 
species in this rule, all of which remains valid and applicable but has 
not been reprinted in this final rule, including a subsection entitled 
Marine Mammal Hearing that described the importance of sound to marine 
mammals and characterized the different groups of marine mammals based 
on their hearing sensitivity. Therefore, we refer the reader to our 
Federal Register notice of proposed rulemaking (85 FR 33914; June 2, 
2020) for more information.
    Information on the status, distribution, abundance, population 
trends, habitat, and ecology of marine mammals in the NWTT Study Area 
may be found in Chapter 4 of the Navy's rulemaking/LOA application. 
NMFS has reviewed this information and found it to be accurate and 
complete. Additional information on the general biology and ecology of 
marine mammals is included in the 2020 NWTT FSEIS/OEIS. Table 9 
incorporates data from the U.S. Pacific and the Alaska Marine Mammal 
Stock Assessment Reports (SARs) (Carretta et al., 2020; Muto et al., 
2020), as well as incorporating the best available science, including 
monitoring data, from the Navy's marine mammal research efforts. NMFS 
has also reviewed new scientific literature since publication of the 
proposed rule, and determined that none of these nor any other new 
information changes our determination of which species have the 
potential to be affected by the Navy's activities or the information 
pertinent to status, distribution, abundance, population trends, 
habitat, or ecology of the species in this final rulemaking, except as 
noted below or, in the case of revised harbor seal abundance, in the 
applicable section of the Analysis and Negligible Impact Determination 
section.

                                                              Table 9--Marine Mammal Expected Occurrence Within the NWTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                     Stock abundance (CV,                                        Occurrence \8\
                                                                                 ESA/MMPA status;      Nmin, most recent               Annual --------------------------------------------------
           Common name                Scientific name            Stock          strategic (Y/N) \1\    abundance survey)      PBR       M/SI                                       Western behm
                                                                                                              \2\                       \3\     Offshore area    Inland waters        canal
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Family Eschrichtiidae:
    Gray whale...................  Eschrichtius          Eastern North         -, -, N.............  26.960 (0.05,               801      139  Seasonal.......  Seasonal
                                    robustus.             Pacific.                                    25,849, 2016).
                                   ....................  Western North         E, D, Y.............  290 (NA, 271, 2016).       0.12      UNK  Rare...........  Rare
                                                          Pacific.
Family Balaenopteridae
 (rorquals):
    Blue whale...................  Balaenoptera          Eastern North         E, D, Y.............  1,496 (0.44, 1,050,         1.2   >=19.4  Seasonal
                                    musculus.             Pacific.                                    2014).
    Fin whale....................  Balaenoptera          Northeast Pacific...  E, D, Y.............  3,168 (0.26, 2,554,         5.1      0.4                                    Rare.
                                    physalus.                                                         2013) \4\.
                                                         CA/OR/WA............  E, D, Y.............  9,029 (0.12, 8,127,          81   >=43.5  Seasonal.......  Rare
                                                                                                      2014).
    Humpback whale...............  Megaptera             Central North         T/E\5\, D, Y........  10,103 (0.3, 7,891,          83       25  Regular........  Regular........  Regular.
                                    novaeangliae.         Pacific.                                    2006).
                                                         CA/OR/WA............  T/E\5\, D, Y........  2,900 (0.05, 2,784,        16.7   >=42.1  Regular........  Regular........  Regular.
                                                                                                      2014).
    Minke whale..................  Balaenoptera          Alaska..............  -, -, N.............  UNK.................        UND        0  ...............  ...............  Rare.
                                    acutorostrata.
                                                         CA/OR/WA............  -, -, N.............  636 (0.72, 369,             3.5    >=1.3  Regular........  Seasonal
                                                                                                      2014).
    Sei whale....................  Balaenoptera          Eastern North         E, D, Y.............  519 (0.4, 374, 2014)       0.75    >=0.2  Regular
                                    borealis.             Pacific.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Family Physeteridae:
    Sperm whale..................  Physeter              CA/OR/WA............  E, D, Y.............  1.997 (0.57, 1,270,         2.5      0.6  Regular
                                    macrocephalus.                                                    2014).
Family Kogiidae:
    Dwarf sperm whale............  Kogia sima..........  CA/OR/WA............  -, -, N.............  UNK.................        UND        0  Rare
    Pygmy sperm whale............  Kogia breviceps.....  CA/OR/WA............  -, -, N.............  4,111 (1.12, 1,924,        19.2        0  Regular
                                                                                                      2014).
Family Ziphiidae (beaked whales):
    Baird's beaked whale.........  Berardius bairdii...  CA/OR/WA............  -, -, N.............  2,697 (0.6, 1,633,           16        0  Regular
                                                                                                      2014).
    Cuvier's beaked whale........  Ziphius cavirostris.  CA/OR/WA............  -, -, N.............  3,274 (0.67, 2,059,          21     <0.1  Regular
                                                                                                      2014).
    Mesoplodont beaked whales....  Mesoplodon species..  CA/OR/WA............  -, -, N.............  3,044 (0.54, 1,967,          20      0.1  Regular
                                                                                                      2014).
Family Delphinidae:
    Common bottlenose dolphin....  Tursiops truncatus..  CA/OR/WA Offshore...  -, -, N.............  1,924 (0.54, 1,255,          11    >=1.6  Regular
                                                                                                      2014).
    Killer whale.................  Orcinus orca........  Eastern North         -, -, N.............  2,347 (UNK, 2,347,           24        1  ...............  ...............  Regular.
                                                          Pacific Alaska                              2012) \6\.
                                                          Resident.
                                                         Eastern North         -, -, N.............  302 (UNK, 302, 2018)        2.2      0.2  Seasonal.......  Seasonal
                                                          Pacific Northern                            \6\.
                                                          Resident.
                                                         West Coast Transient  -, -, N.............  243 (UNK, 243, 2009)        2.4        0  Regular........  Regular........  Regular.
                                                         Eastern North         -, -, N.............  300 (0.1, 276, 2012)        2.8        0  Regular........  ...............  Regular.
                                                          Pacific Offshore.
                                                         Eastern North         E, D, Y.............  75 (NA, 75, 2018)...       0.13        0  Regular........  Regular
                                                          Pacific Southern
                                                          Resident.
    Northern right whale dolphin.  Lissodelphus          CA/OR/WA............  -, -, N.............  26,556 (0.44,               179      3.8  Regular
                                    borealis.                                                         18,608, 2014).
    Pacific white-sided dolphin..  Lagenorhynchus        North Pacific.......  -, -, N.............  26,880 (UNK, NA,            UND        0  ...............  ...............  Regular.
                                    obliquidens.                                                      1990).
                                                         CA/OR/WA............  -, -, N.............  26,814 (0.28,               191      7.5  Regular........  Regular........
                                                                                                      21,195, 2014).
    Risso's dolphin..............  Grampus griseus.....  CA/OR/WA............  -, -, N.............  6,336 (0.32, 4,817,          46    >=3.7  Regular........  Rare
                                                                                                      2014).
    Short-beaked common dolphin..  Delphinus delphis...  CA/OR/WA............  -, -, N.............  969,861 (0.17,            8,393     >=40  Regular........  Rare
                                                                                                      839,325, 2014).

[[Page 72373]]

 
    Short-finned pilot whale.....  Globicephala          CA/OR/WA............  -, -, N.............  836 (0.79, 466,             4.5      1.2  Regular........  Rare...........
                                    macrorhynchus.                                                    2014).
    Striped dolphin..............  Stenella              CA/OR/WA............  -, -, N.............  29,211 (0.2, 24,782,        238    >=0.8  Regular
                                    coeruleoalba.                                                     2014).
Family Phocoenidae (porpoises):
    Dall's porpoise..............  Phocoenoides dalli..  Alaska..............  -, -, N.............  83,400 (0.097, NA,          UND       38  ...............  ...............  Regular.
                                                                                                      1991).
                                                         CA/OR/WA............  -, -, N.............  25,750 (0.45,               172      0.3  Regular........  Regular
                                                                                                      17,954, 2014).
    Harbor porpoise..............  Phocoena phocoena...  Southeast Alaska....  -, -, Y.............  1,354 (0.12, 1,224,          12       34  ...............  ...............  Regular.
                                                                                                      2012).
                                                         Northern OR/WA Coast  -, -, N.............  21,487 (0.44,               151      >=3  Regular
                                                                                                      15,123, 2011).
                                                         Northern CA/Southern  -, -, N.............  24,195 (0.40,               349    >=0.2  Regular
                                                          OR.                                         17,447, 2016).
                                                         Washington Inland     -, -, N.............  11,233 (0.37, 8,308,         66    >=7.2  ...............  Regular
                                                          Waters.                                     2015).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                             Order Carnivora--Superfamily Pinnipedia
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
 sea lions):
    California sea lion..........  Zalophus              U.S.................  -, -, N.............  257,606 (NA,             14,011    >=321  Seasonal.......  Regular
                                    californianus.                                                    233,515, 2014).
    Guadalupe fur seal...........  Arctocephalus         Mexico to California  T, D, Y.............  34,187 (NA, 31,109,       1,062    >=3.8  Seasonal
                                    townsendi.                                                        2013).
    Northern fur seal............  Callorhinus ursinus.  Eastern Pacific.....  -, D, Y.............  620,660 (0.2,            11,295      399  Regular........  ...............  Seasonal.
                                                                                                      525,333, 2016).
                                                         California..........  -, -, N.............  14,050 (NA, 7,524,          451      1.8  Regular
                                                                                                      2013).
    Steller sea lion.............  Eumetopias jubatus..  Eastern U.S.........  -, -, N.............  43,201 (NA, 43,201,       2,592      112  Regular........  Seasonal.......  Regular.
                                                                                                      2017) \7\.
Family Phocidae (earless seals):
    Harbor seal..................  Phoca vitulina......  Southeast Alaska      -, -, N.............  27,659 (UNK, 24,854,        746       40  ...............  ...............  Regular.
                                                          (Clarence Strait).                          2015).
                                                         OR/WA Coast.........  -, -, N.............  UNK.................        UND     10.6  Regular........  Seasonal
                                                         California..........  -, -, N.............  30,968 (0.157,            1,641       43  Regular
                                                                                                      27,348, 2012).
                                                         Washington Northern   -, -, N.............  UNK.................        UND      9.8  Seasonal.......  Regular
                                                          Inland Waters.
                                                         Hood Canal..........  -, -, N.............  UNK.................        UND      0.2  Seasonal.......  Regular
                                                         Southern Puget Sound  -, -, N.............  UNK.................        UND      3.4  Seasonal.......  Regular
Northern Elephant seal:            Mirounga              California..........  -, -, N.............  179,000 (NA, 81,368,      4,882      8.8  Regular........  Regular........  Seasonal.
                                    angustirostris.                                                   2010).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or designated as depleted
  under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds potential biological removal (PBR) or which is determined to be
  declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is automatically designated under the MMPA as depleted and as a
  strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments. CV is coefficient of variation;
  Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable. For the Eastern North Pacific Southern Resident stock of killer whales Nbest/Nmin are based on a direct
  count of individually identifiable animals. The population size of the U.S. stock of California sea lion was estimated from a 1975-2014 time series of pup counts (Lowry et al. 2017),
  combined with mark-recapture estimates of survival rates (DeLong et al. 2017, Laake et al. 2018). The population size of the Mexico to California stock of Guadalupe fur seals was estimated
  from pup count data collected in 2013 and a range of correction factors applied to pup counts to account for uncounted age classes and pre-census pup mortality (Garc[iacute]a-Aguilar et al.
  2018). The population size of the California stock of Northern fur seals was estimated from pup counts multiplied by an expansion factor (San Miguel Island) and maximum pup, juvenile, and
  adult counts (Farrallon Islands) at rookeries. The population size of the Eastern U.S. stock of Steller sea lions was estimated from pup counts and non-pup counts at rookeries in Southeast
  Alaska, British Columbia, Oregon, and California. The population size of the California stock of Northern Elephant seals was estimated from pup counts at rookeries multiplied by the inverse
  of the expected ratio of pups to total animals (McCann, 1985; Lowry et al., 2014).
\3\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality and serious injury (M/SI) from all sources combined (e.g., commercial fisheries, ship strike). Annual
  mortality or serious injury (M/SI) often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV associated with estimated mortality due to commercial
  fisheries is presented in some cases.
\4\ The SAR reports this stock abundance assessment as provisional and notes that it is an underestimate for the entire stock because it is based on surveys which covered only a small portion
  of the stock's range.
\5\ Humpback whales in the Central North Pacific stock and the CA/OR/WA stock are from three Distinct Population Segments (DPSs) based on animals identified in breeding areas in Hawaii,
  Mexico, and Central America. Both stocks and all three DPSs co-occur in the NWTT Study Area.
\6\ Stock abundance estimate is based on counts of individual animals identified from photo-identification catalogues. Surveys for abundance estimates of these stocks are conducted
  infrequently.
\7\ Stock abundance estimate is the best estimate counts, which have not been corrected to account for animals at sea during abundance surveys.
\8\ A ``-'' indicates the species or stock does not occur in that area.
Note--Unknown (UNK); Undetermined (UND); Not Applicable (NA); California (CA); Oregon (OR); Washington (WA).

    Below, we include additional information about the marine mammals 
in the area of the specified activities that informs our analysis, such 
as identifying known areas of important habitat or behaviors, or where 
Unusual Mortality Events (UME) have been designated.

Critical Habitat

    Currently, only the distinct population segment (DPS) of Southern 
Resident killer whale has ESA-designated critical habitat in the NWTT 
Study Area. NMFS has published two proposed rules, however, proposing 
new or revised ESA-designated critical habitat for Southern Resident 
killer whale (84 FR 49214; September 19, 2019) and humpback whales (84 
FR 54354; October 9, 2019).
    NMFS designated critical habitat for the Southern Resident killer 
whale DPS on November 29, 2006 (71 FR 69054) in inland waters of 
Washington State. Based on the natural history of the Southern Resident 
killer whales and their habitat needs, NMFS identified physical or 
biological features essential to the conservation of the Southern 
Resident killer whale DPS: (1) Water quality to support growth and 
development; (2) prey species of sufficient quantity, quality, and 
availability to support individual growth, reproduction, and 
development, as well as overall population growth; and (3) passage 
conditions to allow for migration, resting, and foraging. ESA-
designated critical habitat consists of three areas: (1) The Summer 
Core Area in Haro Strait and waters around the

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San Juan Islands; (2) Puget Sound; and (3) the Strait of Juan de Fuca, 
which comprise approximately 2,560 square miles (mi\2\) (6,630 square 
kilometers (km\2\)) of marine habitat. In designating critical habitat, 
NMFS considered economic impacts and impacts to national security, and 
concluded that the benefits of exclusion of 18 military sites, 
comprising approximately 112 mi\2\ (291 km\2\), outweighed the benefits 
of inclusion because of national security impacts.
    On January 21, 2014, NMFS received a petition requesting revisions 
to the Southern Resident killer whale critical habitat designation. The 
petition requested that NMFS revise critical habitat to include 
``inhabited marine waters along the West Coast of the United States 
that constitute essential foraging and wintering areas,'' specifically 
the region between Cape Flattery, Washington and Point Reyes, 
California extending from the coast to a distance of 47.2 mi (76 km) 
offshore. The petition also requested that NMFS adopt a fourth 
essential habitat feature in both current and expanded critical habitat 
relating to in-water sound levels. On September 19, 2019 (84 FR 54354), 
NMFS published a proposed rule proposing to revise the critical habitat 
designation for the Southern Resident killer whale DPS by designating 
six new areas (using the same essential features determined in 2006, 
and not including the requested essential feature relating to in-water 
sound levels) along the U.S. West Coast. Specific new areas proposed 
along the U.S. West Coast include 15,626.6 mi\2\ (40,472.7 km\2\) of 
marine waters between the 6.1 m (20 ft) depth contour and the 200 m 
(656.2 ft) depth contour from the U.S. international border with Canada 
south to Point Sur, California.
    For humpback whales, on September 8, 2016, NMFS revised the listing 
of humpback whales under the ESA by removing the original, taxonomic-
level species listing, and in its place listing four DPSs as endangered 
and one DPS as threatened (81 FR 62260). NMFS also determined that nine 
additional DPSs did not warrant listing. This listing of DPSs of 
humpback whales under the ESA in 2016 triggered the requirement to 
designate critical habitat, to the maximum extent prudent and 
determinable, for those DPSs occurring in areas under U.S. 
jurisdiction--specifically, the Central America, Mexico, and Western 
North Pacific DPSs.
    In the proposed rule to revise the humpback whale listing, NMFS 
solicited information that could inform a critical habitat designation 
(80 FR 22304; April 21, 2015), but NMFS did not receive relevant data 
or information regarding habitats or habitat features in areas within 
U.S. jurisdiction. In the final rule listing the five DPSs of humpback 
whales, NMFS concluded that critical habitat was not yet determinable, 
which had the effect of extending by one year the statutory deadline 
for designating critical habitat (16 U.S.C. 1533(b)(6)(C)(ii)).
    On October 9, 2019, NMFS proposed to designate critical habitat for 
the endangered Western North Pacific DPS, the endangered Central 
America DPS, and the threatened Mexico DPS of humpback whales (84 FR 
54354). Areas proposed as critical habitat include specific marine 
areas located off the coasts of California, Oregon, Washington, and 
Alaska. Based on consideration of national security and economic 
impacts, NMFS also proposed to exclude multiple areas from the 
designation for each DPS.
    NMFS, in the proposed rule, identified prey species, primarily 
euphausiids and small pelagic schooling fishes of sufficient quality, 
abundance, and accessibility within humpback whale feeding areas to 
support feeding and population growth, as an essential habitat feature. 
NMFS, through a critical habitat review team (CHRT), also considered 
inclusion of migratory corridors and passage features, as well as sound 
and the soundscape, as essential habitat features. NMFS did not propose 
to include either, however, as the CHRT concluded that the best 
available science did not allow for identification of any consistently 
used migratory corridors or definition of any physical, essential 
migratory or passage conditions for whales transiting between or within 
habitats of the three DPSs. The best available science also currently 
does not enable NMFS to identify particular sound levels or to describe 
a certain soundscape feature that is essential to the conservation of 
humpback whales.

Biologically Important Areas

    Biologically Important Areas (BIAs) include areas of known 
importance for reproduction, feeding, or migration, or areas where 
small and resident populations are known to occur (Van Parijs, 2015). 
Unlike ESA critical habitat, these areas are not formally designated 
pursuant to any statute or law, but are a compilation of the best 
available science intended to inform impact and mitigation analyses. An 
interactive map of the BIAs may be found here: https://cetsound.noaa.gov/biologically-important-area-map.
    BIAs off the West Coast of the United States (including 
southeastern Alaska) that overlap portions of the NWTT Study Area 
include the following feeding and migration areas: Northern Puget Sound 
Feeding Area for gray whales (March-May); Northwest Feeding Area for 
gray whales (May-November); Northbound Migration Phase A for gray 
whales (January-July); Northbound Migration Phase B for gray whales 
(March-July); Southbound Migration for gray whales (October-March); 
Northern Washington Feeding Area for humpback whales (May-November); 
Stonewall and Heceta Bank Feeding Area for humpback whales (May-
November); and Point St. George Feeding Area for humpback whales (July-
November) (Calambokidis et al., 2015).
    The NWTT Study Area overlaps with the Northern Puget Sound Feeding 
Area for gray whales and the Northwest Feeding Area for gray whales. 
Gray whale migration corridor BIAs (Northbound and Southbound) overlap 
with the NWTT Study Area, but only in a portion of the Northwest coast 
of Washington, approximately from Pacific Beach and extending north to 
the Strait of Juan de Fuca. The offshore Northern Washington Feeding 
Area for humpback whales is located entirely within the NWTT Study Area 
boundaries. The Stonewall and Heceta Bank Feeding Area for humpback 
whales only partially overlaps with the NWTT Study Area, and the Point 
St. George Feeding Area for humpback whales has extremely limited 
overlap with the Study Area since they abut approximately 12 nmi from 
shore which is where the NWTT Study Area boundary begins. To mitigate 
impacts to marine mammals in these BIAs, the Navy will implement 
several procedural mitigation measures and mitigation areas (described 
later in the Mitigation Measures section).

National Marine Sanctuaries

    Under Title III of the Marine Protection, Research, and Sanctuaries 
Act of 1972 (also known as the National Marine Sanctuaries Act (NMSA)), 
NOAA can establish as national marine sanctuaries (NMS), areas of the 
marine environment with special conservation, recreational, ecological, 
historical, cultural, archaeological, scientific, educational, or 
aesthetic qualities. Sanctuary regulations prohibit or regulate 
activities that could destroy, cause the loss of, or injure sanctuary 
resources pursuant to the regulations for that sanctuary and other 
applicable law (15 CFR part 922). NMSs are managed on a site-specific 
basis, and each

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sanctuary has site-specific regulations. Most, but not all, sanctuaries 
have site-specific regulatory exemptions from the prohibitions for 
certain military activities. Separately, section 304(d) of the NMSA 
requires Federal agencies to consult with the Office of National Marine 
Sanctuaries whenever their activities are likely to destroy, cause the 
loss of, or injure a sanctuary resource. One NMS, the Olympic Coast NMS 
managed by the Office of National Marine Sanctuaries, is located within 
the offshore portion of the NWTT Study Area (for a map of the location 
of this NMS see Chapter 6 of the 2020 NWTT FSEIS/OEIS, Figure 6.1-1). 
Additionally, a portion of the Quinault Range Site overlaps with the 
southern end of the Sanctuary.
    The Olympic Coast NMS includes 3,188 mi\2\ of marine waters and 
submerged lands off the Olympic Peninsula coastline. The sanctuary 
extends 25-50 mi. (40.2-80.5 km) seaward, covering much of the 
continental shelf and portions of three major submarine canyons. The 
boundaries of the sanctuary as defined in the Olympic Coast NMS 
regulations (15 CFR part 922, subpart O) extend from Koitlah Point, due 
north to the United States/Canada international boundary, and seaward 
to the 100-fathom isobath (approximately 180 m in depth). The seaward 
boundary of the sanctuary follows the 100-fathom isobath south to a 
point due west of the Copalis River, and cuts across the tops of 
Nitinat, Juan de Fuca, and the Quinault Canyons. The shoreward boundary 
of the sanctuary is at the mean lower low-water line when adjacent to 
American Indian lands and state lands, and includes the intertidal 
areas to the mean higher high-water line when adjacent to federally 
managed lands. When adjacent to rivers and streams, the sanctuary 
boundary cuts across the mouths but does not extend up river or up 
stream. The Olympic Coast NMS includes many types of productive marine 
habitats including kelp forests, subtidal reefs, rocky and sand 
intertidal zones, submarine canyons, rocky deep-sea habitat, and 
plankton-rich upwelling zones. These habitats support the Sanctuary's 
rich biodiversity which includes 29 species of marine mammals that 
reside in or migrate through the Sanctuary (Office of National Marine 
Sanctuaries, 2008). Additional information on the Olympic Coast NMS can 
be found at https://olympiccoast.noaa.gov.
    Mitigation measures in the Olympic Coast NMS include limits on the 
use of MF1 mid-frequency active sonar during testing and training and 
prohibition of explosive Mine Countermeasure and Neutralization Testing 
activities and non-explosive bombing training activities. See the 
Mitigation Areas section of this final rule for additional discussion 
of mitigation measures required in the Olympic Coast National Marine 
Sanctuary.

Unusual Mortality Events (UMEs)

    An UME is defined under Section 410(6) of the MMPA as a stranding 
that is unexpected; involves a significant die-off of any marine mammal 
population; and demands immediate response. Three UMEs with ongoing or 
recently closed investigations in the NWTT Study Area that inform our 
analysis are discussed below. The California sea lion UME in California 
was closed on May 6, 2020. The Guadalupe fur seal UME in California and 
the gray whale UME along the west coast of North America are active and 
involve ongoing investigations.
California Sea Lion UME
    From January 2013 through September 2016, a greater than expected 
number of young malnourished California sea lions (Zalophus 
californianus) stranded along the coast of California. Sea lions 
stranding from an early age (6-8 months old) through two years of age 
(hereafter referred to as juveniles) were consistently underweight 
without other disease processes detected. Of the 8,122 stranded 
juveniles attributed to the UME, 93 percent stranded alive (n=7,587, 
with 3,418 of these released after rehabilitation) and 7 percent 
(n=531) stranded dead. Several factors are hypothesized to have 
impacted the ability of nursing females and young sea lions to acquire 
adequate nutrition for successful pup rearing and juvenile growth. In 
late 2012, decreased anchovy and sardine recruitment (CalCOFI data, 
July 2013) may have led to nutritionally stressed adult females. 
Biotoxins were present at various times throughout the UME, and while 
they were not detected in the stranded juvenile sea lions (whose 
stomachs were empty at the time of stranding), biotoxins may have 
impacted the adult females' ability to support their dependent pups by 
affecting their cognitive function (e.g., navigation, behavior towards 
their offspring). Therefore, the role of biotoxins in this UME, via its 
possible impact on adult females' ability to support their pups, is 
unclear. The proposed primary cause of the UME was malnutrition of sea 
lion pups and yearlings due to ecological factors. These factors 
included shifts in distribution, abundance, and/or quality of sea lion 
prey items around the Channel Island rookeries during critical sea lion 
life history events (nursing by adult females, and transitioning from 
milk to prey by young sea lions). These prey shifts were most likely 
driven by unusual oceanographic conditions at the time due to the 
``Warm Water Blob'' and El Ni[ntilde]o. This investigation closed on 
May 6, 2020. Please refer to: https://www.fisheries.noaa.gov/national/marine-life-distress/2013-2017-california-sea-lion-unusual-mortality-event-california for more information on this UME.
Guadalupe Fur Seal UME
    Increased strandings of Guadalupe fur seals began along the entire 
coast of California in January 2015 and were eight times higher than 
the historical average (approximately 10 seals/yr). Strandings have 
continued since 2015 and remained well above average through 2019. 
Numbers by year are as follows: 2015 (98), 2016 (76), 2017 (62), 2018 
(45), 2019 (116), 2020 (95 as of October 4, 2020). The total number of 
Guadalupe fur seals stranding in California from January 1, 2015, 
through October 4, 2020, in the UME is 492. Additionally, strandings of 
Guadalupe fur seals became elevated in the spring of 2019 in Washington 
and Oregon; subsequently, strandings for seals in these two states have 
been added to the UME starting from January 1, 2019. The current total 
number of strandings in Washington and Oregon is 132 seals, including 
91 (46 in Oregon; 45 in Washington) in 2019 and 41 (30 in Oregon; 11 in 
Washington) in 2020 as of October 4, 2020. Strandings are seasonal and 
generally peak in April through July of each year. The Guadalupe fur 
seal strandings have been mostly weaned pups and juveniles (1-2 years 
old) with both live and dead strandings occurring. Current findings 
from the majority of stranded animals include primary malnutrition with 
secondary bacterial and parasitic infections. When the 2013-2016 
California sea lion UME was active, it was occurring in the same area 
as the California portion of this UME. This investigation is ongoing. 
Please refer to: https://www.fisheries.noaa.gov/national/marine-life-distress/2015-2020-guadalupe-fur-seal-unusual-mortality-event-california for more information on this UME.
Gray Whale UME
    Since January 1, 2019, elevated gray whale strandings have occurred 
along the west coast of North America, from Mexico to Canada. As of 
October 4, 2020, there have been a total of 384 strandings along the 
coasts of the United

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States, Canada, and Mexico, with 200 of those strandings occurring 
along the U.S. coast. Of the strandings on the U.S. coast, 92 have 
occurred in Alaska, 40 in Washington, 9 in Oregon, and 53 in 
California. Partial necropsy examinations conducted on a subset of 
stranded whales have shown evidence of poor to thin body condition in 
some of the whales. Additional findings have included human 
interactions (entanglements or vessel strikes) and pre-mortem killer 
whale predation in several whales. As part of the UME investigation 
process, NOAA has assembled an independent team of scientists to 
coordinate with the Working Group on Marine Mammal Unusual Mortality 
Events to review the data collected, sample stranded whales, consider 
possible causal-linkages between the mortality event and recent ocean 
and ecosystem perturbations, and determine the next steps for the 
investigation. Please refer to: https://www.fisheries.noaa.gov/national/marine-life-distress/2019-2020-gray-whale-unusual-mortality-event-along-west-coast-and for more information on this UME.

Species Not Included in the Analysis

    The species carried forward for analysis (and described in Table 9) 
are those likely to be found in the NWTT Study Area based on the most 
recent data available, and do not include species that may have once 
inhabited or transited the area but have not been sighted in recent 
years (e.g., species which were extirpated from factors such as 19th 
and 20th century commercial exploitation). Several species that may be 
present in the northwest Pacific Ocean have an extremely low 
probability of presence in the NWTT Study Area. These species are 
considered extralimital (not anticipated to occur in the Study Area) or 
rare (occur in the Study Area sporadically, but sightings are rare). 
These species/stocks include the Eastern North Pacific stock of Bryde's 
whale (Balaenoptera edeni), Eastern North Pacific stock of North 
Pacific right whale (Eubalaena japonica), false killer whale (Pseudorca 
crassidens), long-beaked common dolphin (Delphinus capensis), Western 
U.S. stock of Steller sea lion (Eumetopias jubatus), and Alaska stock 
of Cuvier's beaked whale (Ziphius cavirostris). These species are 
unlikely to occur in the NWTT Study Area and the reasons for not 
including each was explained in further detail in the proposed 
rulemaking (85 FR 33914; June 2, 2020).

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    We provided a detailed discussion of the potential effects of the 
specified activities on marine mammals and their habitat in our Federal 
Register notice of proposed rulemaking (85 FR 33914; June 2, 2020). In 
the Potential Effects of Specified Activities on Marine Mammals and 
Their Habitat section of the proposed rule, NMFS provided a description 
of the ways marine mammals may be affected by these activities in the 
form of, among other things, serious injury or mortality, physical 
trauma, sensory impairment (permanent and temporary threshold shift and 
acoustic masking), physiological responses (particularly stress 
responses), behavioral disturbance, or habitat effects. All of this 
information remains valid and applicable. Therefore, we do not reprint 
the information here, but refer the reader to that document.
    NMFS has also reviewed new relevant information from the scientific 
literature since publication of the proposed rule. Summaries of the new 
key scientific literature since publication of the proposed rule are 
presented below.
    Temporary hearing shifts have been documented in harbor seals and 
harbor porpoises with onset levels varying as a function of frequency. 
Harbor seals experienced TTS 1-4 minutes after exposure to a continuous 
one-sixth-octave noise band centered at 32 kHz at sound pressure levels 
of 92 to 152 dB re 1 [mu]Pa (Kastelein et al. 2020a), with the maximum 
TTS at 32 kHz occurring below ~176 dB re 1 [mu]Pa\2\s. These seals 
appeared to be equally susceptible to TTS caused by sounds in the 2.5-
32 kHz range, but experienced TTS at 45 kHz occurring above ~176 dB re 
1 [mu]Pa\2\s (Kastelein et al. 2020a).
    Harbor porpoises also experience variable temporary hearing shifts 
as a function of frequency. Kastelein et al. (2020b) documented TTS in 
one porpoise due to a one-sixth-octave noise band centered at 63 kHz 
from 154-181 dB re 1 [micro]Pa\2\s 1-4 minutes after exposure, and to 
another porpoise exposed 1-4 minutes to a 88.4 kHz signal at 192 dB re 
1 [micro]Pa\2\s (no TTS was apparent in either animal at 10 or 125 
kHz).
    Accomando et al. (2020) examined the directional dependence of 
hearing thresholds for 2, 10, 20, and 30 kHz in two adult bottlenose 
dolphins. They observed that source direction (i.e., the relative angle 
between the sound source location and the dolphin) impacted hearing 
thresholds for these frequencies. Sounds projected from directly behind 
the dolphins resulted in frequency-dependent increases in hearing 
thresholds of up to 18.5 dB when compared to sounds projected from in 
front of the dolphins. Sounds projected directly above the dolphins 
resulted in thresholds that were approximately 8 dB higher than those 
obtained when sounds were projected below the dolphins. These findings 
suggest that dolphins may receive lower source levels when they are 
oriented 180 degrees away from the sound source, and that dolphins are 
less sensitive to sound projected from above (leading to some spatial 
release from masking). Directional or spatial hearing also allows 
animals to locate sound sources. This study indicates dolphins can 
detect source direction at lower frequencies than previously thought, 
allowing them to successfully avoid or approach biologically 
significant or anthropogenic sound sources at these frequencies.
    Houser et al. (2020) measured cortisol, aldosterone, and 
epinephrine levels in the blood samples of 30 bottlenose dolphins 
before and after exposure to simulated U.S. Navy mid-frequency sonar 
from 115-185 dB re: 1 [mu]Pa. They collected blood samples 
approximately one week prior to, immediately following, and 
approximately one week after exposures and analyzed for hormones via 
radioimmunoassay. Aldosterone levels were below the detection limits in 
all samples. While the observed severity of behavioral responses scaled 
(increased) with SPL, levels of cortisol and epinephrine did not show 
consistent relationships with received SPL. The authors note that it is 
still unclear whether intermittent, high-level acoustic stimuli elicit 
endocrine responses consistent with a stress response, and that 
additional research is needed to determine the relationship between 
behavioral responses and physiological responses.
    In an effort to compare behavioral responses to continuous active 
sonar (CAS) and pulsed (intermittent) active sonar (PAS), Isojunno et 
al. (2020) conducted at-sea experiments on 16 sperm whales equipped 
with animal-attached sound- and movement-recording tags in Norway. They 
examined changes in foraging effort and proxies for foraging success 
and cost during sonar and control exposures after accounting for 
baseline variation. They observed no reduction in time spent foraging 
during exposures to medium-level PAS transmitted at the same peak 
amplitude as CAS, however they observed similar reductions in foraging 
during CAS and PAS when they were received at similar energy levels 
(SELs).

[[Page 72377]]

The authors note that these results support the hypothesis that sound 
energy (SEL) is the main cause of behavioral responses rather than 
sound amplitude (SPL), and that exposure context and measurements of 
cumulative sound energy are important considerations for future 
research and noise impact assessments.
    Frankel and Stein (2020) used shoreline theodolite tracking to 
examine potential behavioral responses of southbound migrating eastern 
gray whales to a high-frequency active sonar system transmitted by a 
vessel located off the coast of California. The sonar transducer 
deployed from the vessel transmitted 21-25 kHz sweeps for half of each 
day (experimental period), and no sound the other half of the day 
(control period). In contrast to low-frequency active sonar tests 
conducted in the same area (Clark et al., 1999; Tyack and Clark, 1998), 
no overt behavioral responses or deflections were observed in field or 
visual data. However, statistical analysis of the tracking data 
indicated that during experimental periods at received levels of 
approximately 148 dB re: 1 [mu]Pa2 (134 dB re: 1 [mu]Pa2 s) and less 
than 2 km from the transmitting vessel, gray whales deflected their 
migration paths inshore from the vessel. The authors indicate that 
these data suggest the functional hearing sensitivity of gray whales 
extends to at least 21 kHz. These findings agree with the predicted 
mysticete hearing curve and BRFs used in the analysis to estimate take 
by Level A harassment (PTS) and Level B harassment (behavioral 
response) for this rule (see the Technical Report Criteria and 
Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase 
III)).
    In February 2020, a study (Simonis et al., 2020) was published 
titled ``Co-occurrence of beaked whale strandings and naval sonar in 
the Mariana Islands, Western Pacific.'' In summary, the authors 
compiled the publicly available information regarding Navy training 
exercises from 2006-2019 (from press releases, etc.), as well as the 
passive acoustic monitoring data indicating sonar use that they 
collected at two specific locations on HARP recorders over a shorter 
amount of time, and compared it to the dates of beaked whale 
strandings. Using this data, they reported that six of the 10 Cuvier's 
beaked whales, from four of eight events, stranded during or within six 
days of a naval ASW exercise using sonar. In a Note to the article, the 
authors acknowledged additional information provided by the Navy while 
the article was in press that one of the strandings occurred a day 
prior to sonar transmissions and so should not be considered coincident 
with sonar. The authors' analysis examined the probability that three 
of eight random days would fall during, or within six days after, a 
naval event (utilizing the Navy training events and sonar detections of 
which the authors were aware). Their test results indicated that the 
probability that three of eight stranding events were randomly 
associated with naval sonar was one percent.
    The authors did not have access to the Navy's classified data (in 
the Note added to the article, Simonis et al. noted that the Navy was 
working with NMFS to make the broader classified dataset available for 
further statistical analysis). Later reporting by the Navy indicated 
there were more than three times as many sonar days in the Marianas 
during the designated time period than Simonis et al. (2020) reported. 
Primarily for this reason, the Navy tasked the Center for Naval 
Analysis (CNA) with repeating the statistical examination of Simonis et 
al. using the full classified sonar record, including ship movement 
information to document the precise times and locations of Navy sonar 
use throughout the time period of consideration (2007-2019).
    The results of the Simonis et al. (2020) paper and the CNA analysis 
both suggest (the latter to a notably lesser degree) that it is more 
probable than not that there was some form of non-random relationship 
between sonar days and strandings in the Marianas during this period of 
time; however, the results of the Navy analysis (using the full 
dataset) allow, statistically, that the strandings and sonar use may 
not be related.
    Varghese et al. (2020) analyzed group vocal periods from Cuvier's 
beaked whales during multibeam echosounder activity recorded in the 
Southern California Antisubmarine Warfare Range, and failed to find any 
clear evidence of behavioral response due to the echosounder survey. 
The whales did not leave the range or cease foraging.
    De Soto et al. (2020) hypothesized that the high degree of vocal 
synchrony in beaked whales during their deep foraging dives, coupled 
with their silent, low-angled ascents, have evolved as an anti-predator 
response to killer whales. Since killer whales do not dive deep when 
foraging and so may be waiting at the surface for animals to finish a 
dive, these authors speculated that by diving in spatial and vocal 
cohesion with all members of their group, and by surfacing silently and 
up to a kilometer away from where they were vocally active during the 
dive, they minimize the ability of killer whales to locate them when at 
the surface. This may lead to a trade-off for the larger, more fit 
animals that could conduct longer foraging dives, such that all members 
of the group remain together and are better protected by this behavior. 
The authors further speculate that this may explain the long, slow, 
silent, and shallow ascents that beaked whales make when sonar occurs 
during a deep foraging dive. However, these hypotheses are based only 
on the dive behavior of tagged beaked whales, with no observations of 
predation attempts by killer whales, and need to be tested further to 
be validated.
    Having considered the new information, along with information 
provided in public comments on the proposed rule, we have determined 
that there is no new information that substantively affects our 
analysis of potential impacts on marine mammals and their habitat that 
appeared in the proposed rule, all of which remains applicable and 
valid for our assessment of the effects of the Navy's activities during 
the seven-year period of this rule.

Estimated Take of Marine Mammals

    This section indicates the number of takes that NMFS is 
authorizing, which is based on the amount of take that NMFS anticipates 
could occur or the maximum amount that is reasonably likely to occur, 
depending on the type of take and the methods used to estimate it, as 
described in detail below. NMFS coordinated closely with the Navy in 
the development of their incidental take application, and agrees that 
the methods the Navy has put forth described herein to estimate take 
(including the model, thresholds, and density estimates), and the 
resulting numbers are based on the best available science and 
appropriate for authorization. Nonetheless, since publication of the 
proposed rule, the Navy has adjusted their planned activity by reducing 
the number of times Mine Countermeasure and Neutralization testing 
could occur over the seven-year authorization. This change in action 
resulted in decreases in estimated take over seven years for the 
following species: fin whale, sei whale, minke whale, humpback whale, 
gray whale, northern right whale dolphin, Pacific white-sided dolphin, 
Risso's dolphin, Kogia whales, Dall's porpoise, harbor porpoise, 
California sea lion, Steller sea lion, harbor seal, and northern 
elephant seal. These changes also resulted in a reduction in HF4 sonar 
hours associated with Mine Countermeasure and

[[Page 72378]]

Neutralization testing; however, this reduction is not shown 
quantitatively.
    Takes are predominantly in the form of harassment, but a small 
number of mortalities are also possible. For a military readiness 
activity, the MMPA defines ``harassment'' as (i) Any act that injures 
or has the significant potential to injure a marine mammal or marine 
mammal stock in the wild (Level A Harassment); or (ii) Any act that 
disturbs or is likely to disturb a marine mammal or marine mammal stock 
in the wild by causing disruption of natural behavioral patterns, 
including, but not limited to, migration, surfacing, nursing, breeding, 
feeding, or sheltering, to a point where such behavioral patterns are 
abandoned or significantly altered (Level B Harassment).
    Authorized takes will primarily be in the form of Level B 
harassment, as use of the acoustic and explosive sources (i.e., sonar 
and explosives) is more likely to result in behavioral disturbance 
(rising to the level of a take as described above) or temporary 
threshold shift (TTS) for marine mammals than other forms of take. 
There is also the potential for Level A harassment, however, in the 
form of auditory injury, to result from exposure to the sound sources 
utilized in training and testing activities. No Level A harassment from 
tissue damage is anticipated or authorized. Lastly, no more than three 
serious injuries or mortalities total (over the seven-year period) of 
large whales could potentially occur through vessel collisions. 
Although we analyze the impacts of these potential serious injuries or 
mortalities that are authorized, the planned mitigation and monitoring 
measures are expected to minimize the likelihood (i.e., further lower 
the already low probability) that ship strike (and the associated 
serious injury or mortality) would occur.
    The Navy has not requested, and NMFS does not anticipate or 
authorize, incidental take by mortality of beaked whales or any other 
species as a result of sonar use. As discussed in the proposed rule, 
there are a few cases where active naval sonar (in the United States 
or, largely, elsewhere) has either potentially contributed to or been 
more definitively causally linked with marine mammal mass strandings. 
There are a suite of factors that have been associated with these 
specific cases of strandings (steep bathymetry, multiple hull-mounted 
platforms using sonar simultaneously, constricted channels, strong 
surface ducts, etc.) that are not present together in the NWTT Study 
Area and during the specified activities. The number of incidences of 
strandings resulting from exposure to active sonar are few worldwide, 
there are no major training exercises utilizing multiple-hull-mounted 
sonar in the NWTT Study Area, the overall amount of active sonar use is 
low relative to other Navy Study Areas, and there have not been any 
documented mass strandings of any cetacean species in the NWTT Study 
Area. Accordingly, mortality is not anticipated or authorized.
    Generally speaking, for acoustic impacts NMFS estimates the amount 
and type of harassment by considering: (1) Acoustic thresholds above 
which NMFS believes the best available science indicates marine mammals 
will be taken by behavioral disturbance (in this case, as defined in 
the military readiness definition of Level B harassment included above) 
or incur some degree of temporary or permanent hearing impairment; (2) 
the area or volume of water that will be ensonified above these levels 
in a day or event; (3) the density or occurrence of marine mammals 
within these ensonified areas; and (4) the number of days of activities 
or events. Below, we describe these components in more detail and 
present the take estimates.

Acoustic Thresholds

    Using the best available science, NMFS, in coordination with the 
Navy, has established acoustic thresholds that identify the most 
appropriate received level of underwater sound above which marine 
mammals exposed to these sound sources could be reasonably expected to 
experience a disruption in behavior patterns to a point where they are 
abandoned or significantly altered, or to incur TTS (equated to Level B 
harassment) or PTS of some degree (equated to Level A harassment). 
Thresholds have also been developed to identify the pressure levels 
above which animals may incur non-auditory injury from exposure to 
pressure waves from explosive detonation.
    Despite the quickly evolving science, there are still challenges in 
quantifying expected behavioral responses that qualify as take by Level 
B harassment, especially where the goal is to use one or two 
predictable indicators (e.g., received level and distance) to predict 
responses that are also driven by additional factors that cannot be 
easily incorporated into the thresholds (e.g., context). So, while the 
thresholds that identify Level B harassment by behavioral disturbance 
(referred to as ``behavioral harassment thresholds'') have been refined 
to better consider the best available science (e.g., incorporating both 
received level and distance), they also still have some built-in 
conservative factors to address the challenge noted. For example, while 
duration of observed responses in the data are now considered in the 
thresholds, some of the responses that are informing take thresholds 
are of a very short duration, such that it is possible some of these 
responses might not always rise to the level of disrupting behavior 
patterns to a point where they are abandoned or significantly altered. 
We describe the application of this Level B harassment threshold as 
identifying the maximum number of instances in which marine mammals 
could be reasonably expected to experience a disruption in behavior 
patterns to a point where they are abandoned or significantly altered. 
In summary, we believe these thresholds are the most appropriate method 
for predicting Level B harassment by behavioral disturbance given the 
best available science and the associated uncertainty.
Hearing Impairment (TTS/PTS) and Tissue Damage and Mortality
    NMFS' Acoustic Technical Guidance (NMFS, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). The Acoustic Technical Guidance also 
identifies criteria to predict TTS, which is not considered injury and 
falls into the Level B harassment category. The Navy's planned activity 
includes the use of non-impulsive (sonar) and impulsive (explosives) 
sources.
    These thresholds (Tables 10 and 11) were developed by compiling and 
synthesizing the best available science and soliciting input multiple 
times from both the public and peer reviewers. The references, 
analysis, and methodology used in the development of the thresholds are 
described in the Acoustic Technical Guidance, which may be accessed at: 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

[[Page 72379]]



 Table 10--Acoustic Thresholds Identifying the Onset of TTS and PTS for
        Non-Impulsive Sound Sources by Functional Hearing Groups
------------------------------------------------------------------------
                                               Non-impulsive
                                 ---------------------------------------
    Functional hearing group       TTS threshold SEL   PTS threshold SEL
                                      (weighted)          (weighted)
------------------------------------------------------------------------
Low-Frequency Cetaceans.........                 179                 199
Mid-Frequency Cetaceans.........                 178                 198
High-Frequency Cetaceans........                 153                 173
Phocid Pinnipeds (Underwater)...                 181                 201
Otarid Pinnipeds (Underwater)...                 199                 219
------------------------------------------------------------------------
Note: SEL thresholds in dB re: 1 [mu]Pa\2\s.

    Based on the best available science, the Navy (in coordination with 
NMFS) used the acoustic and pressure thresholds indicated in Table 11 
to predict the onset of TTS, PTS, tissue damage, and mortality for 
explosives (impulsive) and other impulsive sound sources.

                         Table 11--Onset of TTS, PTS, Tissue Damage, and Mortality Thresholds for Marine Mammals for Explosives
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                               Mean onset slight  Mean onset  slight      Mean onset
    Functional hearing group            Species          Onset TTS \1\         Onset PTS        GI tract injury      lung  injury          mortality
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-frequency cetaceans.........  All mysticetes....  168 dB SEL          183 dB SEL          237 dB Peak SPL...  Equation 1........  Equation 2.
                                                       (weighted)or 213    (weighted)or 219
                                                       dB Peak SPL.        dB Peak SPL.
Mid-frequency cetaceans.........  Most delphinids,    170 dB              185 dB SEL          237 dB Peak SPL...
                                   medium and large    SEL(weighted) or    (weighted)or 230
                                   toothed whales.     224 dB Peak SPL.    dB Peak SPL.
High-frequency cetaceans........  Porpoises and       140 dB SEL          155 dB SEL          237 dB Peak SPL...
                                   Kogia spp..         (weighted)or 196    (weighted) or 202
                                                       dB Peak SPL.        dB Peak SPL.
Phocidae........................  Harbor seal,        170 dB SEL          185 dB SEL          237 dB Peak SPL...
                                   Hawaiian monk       (weighted)or 212    (weighted)or 218
                                   seal, Northern      dB Peak SPL.        dB Peak SPL.
                                   elephant seal.
Otariidae.......................  California sea      188 dB SEL          203 dB SEL          237 dB Peak SPL...
                                   lion, Guadalupe     (weighted) or 226   (weighted) or 232
                                   fur seal,           dB Peak SPL.        dB Peak SPL.
                                   Northern fur seal.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: (1) Equation 1: 47.5M\1/3\ (1+[DRm/10.1])\1/6\ Pa-sec (2) Equation 2: 103M\1/3\ (1+[DRm/10.1])\1/6\ Pa-sec (3) M = mass of the animals in kg (4)
  DRm = depth of the receiver (animal) in meters (5) SPL = sound pressure level.
\1\ Peak thresholds are unweighted.

    The criteria used to assess the onset of TTS and PTS due to 
exposure to sonars (non-impulsive, see Table 10 above) are discussed 
further in the Navy's rulemaking/LOA application (see Hearing Loss from 
Sonar and Other Transducers in Chapter 6, Section 6.4.2.1, Methods for 
Analyzing Impacts from Sonars and Other Transducers). Refer to the 
Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects 
Analysis (Phase III) report (U.S. Department of the Navy, 2017c) for 
detailed information on how the criteria and thresholds were derived. 
Tables 30 indicates the range to effects for tissue damage for 
different explosive types. Non-auditory injury (i.e., other than PTS) 
and mortality from sonar and other transducers is not reasonably likely 
to result for the reasons explained in the proposed rule under the 
Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat section--Acoustically Mediated Bubble Growth and other 
Pressure-related Injury and the additional discussion in this final 
rule and is therefore not considered further in this analysis.
    The mitigation measures associated with explosives are expected to 
be effective in preventing tissue damage to any potentially affected 
species, and no species are anticipated to incur tissue damage during 
the period of this rule. Specifically, the Navy will implement 
mitigation measures (described in the Mitigation Measures section) 
during explosive activities, including delaying detonations when a 
marine mammal is observed in the mitigation zone. Nearly all explosive 
events will occur during daylight hours to improve the sightability of 
marine mammals and thereby improve mitigation effectiveness. Observing 
for marine mammals during the explosive activities will include visual 
and passive acoustic detection methods (when they are available and 
part of the activity) before the activity begins, in order to cover the 
mitigation zones that can range from 500 yd (457 m) to 2,500 yd (2,286 
m) depending on the source (e.g., explosive sonobuoy, explosive 
torpedo, explosive bombs; see Tables 38-44).
Level B Harassment by Behavioral Disturbance
    Though significantly driven by received level, the onset of Level B 
harassment by behavioral disturbance from anthropogenic noise exposure 
is

[[Page 72380]]

also informed to varying degrees by other factors related to the source 
(e.g., frequency, predictability, duty cycle), the environment (e.g., 
bathymetry), and the receiving animals (hearing, motivation, 
experience, demography, behavioral context) and can be difficult to 
predict (Ellison et al., 2011; Southall et al., 2007). Based on what 
the available science indicates and the practical need to use 
thresholds based on a factor, or factors, that are both predictable and 
measurable for most activities, NMFS uses generalized acoustic 
thresholds based primarily on received level (and distance in some 
cases) to estimate the onset of Level B harassment by behavioral 
disturbance.
Sonar
    As noted above, the Navy coordinated with NMFS to develop, and 
propose for use in this rule, thresholds specific to their military 
readiness activities utilizing active sonar that identify at what 
received level and distance Level B harassment by behavioral 
disturbance would be expected to result. These thresholds are referred 
to as ``behavioral harassment thresholds'' throughout the rest of the 
rule. These behavioral harassment thresholds consist of BRFs and 
associated cutoff distances, and are also referred to, together, as 
``the criteria.'' These criteria are used to estimate the number of 
animals that may exhibit a behavioral response that qualifies as a take 
when exposed to sonar and other transducers. The way the criteria were 
derived is discussed in detail in the Criteria and Thresholds for U.S. 
Navy Acoustic and Explosive Effects Analysis (Phase III) report (U.S. 
Department of the Navy, 2017c). Developing these behavioral harassment 
criteria involved multiple steps. All peer-reviewed published 
behavioral response studies conducted both in the field and on captive 
animals were examined in order to understand the breadth of behavioral 
responses of marine mammals to sonar and other transducers. NMFS has 
carefully reviewed the Navy's criteria, i.e., BRFs and cutoff distances 
for these species, and agrees that they are the best available science 
and the appropriate method to use at this time for determining impacts 
to marine mammals from sonar and other transducers and for calculating 
take and to support the determinations made in this rule. The Navy and 
NMFS will continue to evaluate the information as new science becomes 
available. The criteria have been rigorously vetted within the Navy 
community, among scientists during expert elicitation, and then 
reviewed by the public before being applied. It is not necessary or 
possible to revise and update the criteria and risk functions every 
time a new paper is published. The Navy and NMFS consider new 
information as it becomes available for updates to the criteria in the 
future, when the next round of updated criteria will be developed. Thus 
far, no new information has been published or otherwise conveyed that 
would fundamentally change the assessment of impacts or conclusions of 
the 2020 NWTT FSEIS/OEIS or this rule.
    As discussed above, marine mammal responses to sound (some of which 
are considered disturbances that qualify as a take) are highly variable 
and context specific, i.e., they are affected by differences in 
acoustic conditions; differences between species and populations; 
differences in gender, age, reproductive status, or social behavior; 
and other prior experience of the individuals. This means that there is 
support for considering alternative approaches for estimating Level B 
harassment by behavioral disturbance. Although the statutory definition 
of Level B harassment for military readiness activities means that a 
natural behavioral pattern of a marine mammal is significantly altered 
or abandoned, the current state of science for determining those 
thresholds is somewhat unsettled.
    In its analysis of impacts associated with sonar acoustic sources 
(which was coordinated with NMFS), the Navy used an updated 
conservative approach that likely overestimates the number of takes by 
Level B harassment due to behavioral disturbance and response. Many of 
the behavioral responses identified using the Navy's quantitative 
analysis are most likely to be of moderate severity as described in the 
Southall et al. (2007) behavioral response severity scale. These 
``moderate'' severity responses were considered significant if they 
were sustained for the duration of the exposure or longer. Within the 
Navy's quantitative analysis, many reactions are predicted from 
exposure to sound that may exceed an animal's threshold for Level B 
harassment by behavioral disturbance for only a single exposure (a few 
seconds) to several minutes, and it is likely that some of the 
resulting estimated behavioral responses that are counted as Level B 
harassment would not constitute significant alteration or abandonment 
of the natural behavioral patterns. The Navy and NMFS have used the 
best available science to address the challenging differentiation 
between significant and non-significant behavioral reactions (i.e., 
whether the behavior has been abandoned or significantly altered such 
that it qualifies as harassment), but have erred on the cautious side 
where uncertainty exists (e.g., counting these lower duration reactions 
as take), which likely results in some degree of overestimation of 
Level B harassment by behavioral disturbance. We consider application 
of these behavioral harassment thresholds, therefore, as identifying 
the maximum number of instances in which marine mammals could be 
reasonably expected to experience a disruption in behavior patterns to 
a point where they are abandoned or significantly altered (i.e., Level 
B harassment). Because this is the most appropriate method for 
estimating Level B harassment given the best available science and 
uncertainty on the topic, it is these numbers of Level B harassment by 
behavioral disturbance that are analyzed in the Analysis and Negligible 
Impact Determination section and are authorized.
    In the Navy's acoustic impact analyses during Phase II (the 
previous phase of Navy testing and training, 2015-2020; see also Navy's 
Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects 
Analysis Technical Report, 2012), the likelihood of Level B harassment 
by behavioral disturbance in response to sonar and other transducers 
was based on a probabilistic function (BRF), that related the 
likelihood (i.e., probability) of a behavioral response (at the level 
of a Level B harassment) to the received SPL. The BRF was used to 
estimate the percentage of an exposed population that is likely to 
exhibit Level B harassment due to altered behaviors or behavioral 
disturbance at a given received SPL. This BRF relied on the assumption 
that sound poses a negligible risk to marine mammals if they are 
exposed to SPL below a certain ``basement'' value. Above the basement 
exposure SPL, the probability of a response increased with increasing 
SPL. Two BRFs were used in Navy acoustic impact analyses: BRF1 for 
mysticetes and BRF2 for other species. BRFs were not used for beaked 
whales during Phase II analyses. Instead, a step function at an SPL of 
140 dB re: 1 [mu]Pa was used for beaked whales as the threshold to 
predict Level B harassment by behavioral disturbance.
    Developing the criteria for Level B harassment by behavioral 
disturbance for Phase III (the current phase of Navy training and 
testing activities) involved multiple steps: all available behavioral 
response studies conducted both in the field and on captive animals 
were examined to understand the breadth of behavioral responses of 
marine mammals to sonar and other transducers (see also Navy's Criteria 
and Thresholds

[[Page 72381]]

for U.S. Navy Acoustic and Explosive Effects Analysis (Phase III) 
Technical Report, 2017). Six behavioral response field studies with 
observations of 14 different marine mammal species reactions to sonar 
or sonar-like signals and 6 captive animal behavioral studies with 
observations of 8 different species reactions to sonar or sonar-like 
signals were used to provide a robust data set for the derivation of 
the Navy's Phase III marine mammal behavioral response criteria. All 
behavioral response research that has been published since the 
derivation of the Navy's Phase III criteria (c.a. December 2016) has 
been examined and is consistent with the current BRFs. Marine mammal 
species were placed into behavioral criteria groups based on their 
known or presumed behavioral sensitivities to sound. In most cases 
these divisions were driven by taxonomic classifications (e.g., 
mysticetes, pinnipeds). The data from the behavioral studies were 
analyzed by looking for significant responses, or lack thereof, for 
each experimental session. The resulting four Bayesian Biphasic Dose 
Response Functions (referred to as the BRFs) that were developed for 
odontocetes, pinnipeds, mysticetes, and beaked whales predict the 
probability of a behavioral response qualifying as Level B harassment 
given exposure to certain received levels of sound. These BRFs are then 
used in combination with the cutoff distances described below to 
estimate the number of takes by Level B harassment.
    The Navy used cutoff distances beyond which the potential of 
significant behavioral responses (and therefore Level B harassment) is 
considered to be unlikely (see Table 12 below). This was determined by 
examining all available published field observations of behavioral 
reactions to sonar or sonar-like signals that included the distance 
between the sound source and the marine mammal. The longest distance, 
rounded up to the nearest 5-km increment, was chosen as the cutoff 
distance for each behavioral criteria group (i.e. odontocetes, 
mysticetes, pinnipeds, and beaked whales). For animals within the 
cutoff distance, a BRF based on a received SPL as presented in Chapter 
6, Section 6.4.2.1 (Methods for Analyzing Impacts from Sonars and other 
Transducers) of the Navy's rulemaking/LOA application was used to 
predict the probability of a potential significant behavioral response. 
For training and testing events that contain multiple platforms or 
tactical sonar sources that exceed 215 dB re: 1 [mu]Pa at 1 m, this 
cutoff distance is substantially increased (i.e., doubled) from values 
derived from the literature. The use of multiple platforms and intense 
sound sources are factors that probably increase responsiveness in 
marine mammals overall (however, we note that helicopter dipping sonars 
were considered in the intense sound source group, despite lower source 
levels, because of data indicating that marine mammals are sometimes 
more responsive to the less predictable employment of this source). 
There are currently few behavioral observations under these 
circumstances; therefore, the Navy conservatively predicted significant 
behavioral responses that will rise to Level B harassment at farther 
ranges as shown in Table 12, versus less intense events.

  Table 12--Cutoff Distances for Moderate Source Level, Single Platform
   Training and Testing Events and for All Other Events With Multiple
   Platforms or Sonar With Source Levels at or Exceeding 215 dB re: 1
                            [micro]Pa at 1 m
------------------------------------------------------------------------
                                           Moderate SL/
                                              single      High SL/multi-
             Criteria group                  platform        platform
                                              cutoff          cutoff
                                           distance (km)   distance (km)
------------------------------------------------------------------------
Odontocetes.............................              10              20
Pinnipeds...............................               5              10
Mysticetes..............................              10              20
Beaked Whales...........................              25              50
Harbor Porpoise.........................              20              40
------------------------------------------------------------------------
Notes: dB re: 1 [micro]Pa at 1 m = decibels referenced to 1 micropascal
  at 1 meter, km = kilometer, SL = source level.

    The range to received sound levels in 6-dB steps from five 
representative sonar bins and the percentage of animals that may be 
taken by Level B harassment at the received level and distance 
indicated under each BRF are shown in Tables 13 through 17. Cells are 
shaded if the mean range value for the specified received level exceeds 
the distance cutoff range for a particular hearing group and therefore 
are not included in the estimated take. See Chapter 6, Section 6.4.2.1 
(Methods for Analyzing Impacts from Sonars and Other Transducers) of 
the Navy's rulemaking/LOA application for further details on the 
derivation and use of the BRFs, thresholds, and the cutoff distances to 
identify takes by Level B harassment, which were coordinated with NMFS. 
Table 13 illustrates the maximum likely percentage of exposed 
individuals taken at the indicated received level and associated range 
(in which marine mammals would be reasonably expected to experience a 
disruption in behavioral patterns to a point where they are abandoned 
or significantly altered) for low-frequency active sonar (LFAS). As 
noted previously, NMFS carefully reviewed, and contributed to, the 
Navy's behavioral harassment thresholds (i.e., the BRFs and the cutoff 
distances) for the species, and agrees that these methods represent the 
best available science at this time for determining impacts to marine 
mammals from sonar and other transducers.

[[Page 72382]]



Table 13--Ranges to Estimated Level B Harassment by Behavioral Disturbance for Sonar Bin LF4 Over a Representative Range of Environments Within the NWTT
                                                                       Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Average range (m)                Probability of behavioral response for sonar bin LF4
                                                     with minimum and  ---------------------------------------------------------------------------------
       Received level  (dB re: 1 [micro]Pa)          maximum values in                                                   Beaked whale    Harbor porpoise
                                                        parentheses     Odontocete (%)   Mysticete (%)   Pinniped (%)         (%)              (%)
--------------------------------------------------------------------------------------------------------------------------------------------------------
196...............................................             1 (0-1)             100             100             100             100               100
190...............................................             3 (0-3)             100              98              99             100               100
184...............................................             6 (0-8)              99              88              98             100               100
178...............................................           13 (0-30)              97              59              92             100               100
172...............................................          29 (0-230)              91              30              76              99               100
166...............................................          64 (0-100)              78              20              48              97               100
160...............................................         148 (0-310)              58              18              27              93               100
154...............................................       366 (230-850)              40              17              18              83               100
148...............................................     854 (300-2,025)              29              16              16              66               100
142...............................................   1,774 (300-5,025)              25              13              15              45               100
136...............................................   3,168 (300-8,525)              23               9              15              28               100
130...............................................  5,167 (300-30,525)              20               5              15              18               100
124...............................................  7,554 (300-93,775)              17               2              14              14               100
118...............................................        10,033 (300-              12               1              13              12                 0
                                                             100,000*)
112...............................................        12,700 (300-               6               0               9              11                 0
                                                             100,000*)
106...............................................        15,697 (300-               3               0               5              11                 0
                                                             100,000*)
100...............................................        17,846 (300-               1               0               2               8                 0
                                                             100,000*)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: dB re: 1 [micro]Pa = decibels referenced to 1 micropascal, LF = low-frequency
* Indicates maximum range to which acoustic model was run, a distance of approximately 100 km from the sound source. Cells are shaded if the mean range
  value for the specified received level exceeds the distance cutoff range for a particular hearing group. Any impacts within the cutoff range for a
  criteria group are included in the estimated impacts. Cut-off ranges in this table are for activities with high source levels and/or multiple
  platforms (see Table 12 for behavioral cut-off distances).

    Tables 14 through 16 identify the maximum likely percentage of 
exposed individuals taken at the indicated received level and 
associated range for mid-frequency active sonar (MFAS).

Table 14--Ranges to Estimated Level B Harassment by Behavioral Disturbance for Sonar Bin MF1 Over a Representative Range of Environments Within the NWTT
                                                                       Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Average range (m)    Probability of Level B harassment by behavioral disturbance for Sonar bin MF1
                                                     with minimum and  ---------------------------------------------------------------------------------
       Received level  (dB re: 1 [micro]Pa)          maximum values in                                                   Beaked whale    Harbor porpoise
                                                        parentheses     Odontocete (%)   Mysticete (%)   Pinniped (%)         (%)              (%)
--------------------------------------------------------------------------------------------------------------------------------------------------------
196...............................................        112 (80-170)             100             100             100             100               100
190...............................................        262 (80-410)             100              98              99             100               100
184...............................................      547 (80-1,025)              99              88              98             100               100
178...............................................    1,210 (80-3,775)              97              59              92             100               100
172...............................................    2,508 (80-7,525)              91              30              76              99               100
166...............................................   4,164 (80-16,025)              78              20              48              97               100
160...............................................   6,583 (80-28,775)              58              18              27              93               100
154...............................................  10,410 (80-47,025)              40              17              18              83               100
148...............................................  16,507 (80-63,525)              29              16              16              66               100
142...............................................  21,111 (80-94,025)              25              13              15              45               100
136...............................................  26,182 (80-100,000              23               9              15              28               100
                                                                    *)
130...............................................  31,842 (80-100,000              20               5              15              18               100
                                                                    *)
124...............................................  34,195 (80-100,000              17               2              14              14               100
                                                                    *)
118...............................................  36,557 (80-100,000              12               1              13              12                 0
                                                                    *)
112...............................................  38,166 (80-100,000               6               0               9              11                 0
                                                                    *)
106...............................................  39,571 (80-100,000               3               0               5              11                 0
                                                                    *)
100...............................................  41,303 (80-100,000               1               0               2               8                 0
                                                                    *)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: dB re: 1 [micro]Pa = decibels referenced to 1 micropascal, MF = mid-frequency.

[[Page 72383]]

 
* Indicates maximum range to which acoustic model was run, a distance of approximately 100 km from the sound source. Cells are shaded if the mean range
  value for the specified received level exceeds the distance cutoff range for a particular hearing group. Any impacts within the cutoff range for a
  criteria group are included in the estimated impacts. Cut-off ranges in this table are for activities with high source levels and/or multiple
  platforms (see Table 12 for behavioral cut-off distances).


Table 15--Ranges to Estimated Takes by Level B Harassment by Behavioral Disturbance for Sonar Bin MF4 Over a Representative Range of Environments Within
                                                                   the NWTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Average range (m)    Probability of Level B harassment by behavioral disturbance for Sonar bin MF4
                                                     with minimum and  ---------------------------------------------------------------------------------
       Received level  (dB re: 1 [micro]Pa)          maximum values in
                                                        parentheses       Odontocete       Mysticete       Pinniped      Beaked whale    Harbor porpoise
--------------------------------------------------------------------------------------------------------------------------------------------------------
196...............................................             8 (0-8)             100             100             100             100               100
190...............................................           16 (0-20)             100              98              99             100               100
184...............................................           34 (0-40)              99              88              98             100               100
178...............................................           68 (0-85)              97              59              92             100               100
172...............................................       155 (120-300)              91              30              76              99               100
166...............................................       501 (290-975)              78              20              48              97               100
160...............................................   1,061 (480-2,275)              58              18              27              93               100
154...............................................   1,882 (525-4,025)              40              17              18              83               100
148...............................................   2,885 (525-7,525)              29              16              16              66               100
142...............................................  4,425 (525-14,275)              25              13              15              45               100
136...............................................  9,902 (525-48,275)              23               9              15              28               100
130...............................................        20,234 (525-              20               5              15              18               100
                                                               56,025)
124...............................................        23,684 (525-              17               2              14              14               100
                                                               91,775)
118...............................................        28,727 (525-              12               1              13              12                 0
                                                            100,000 *)
112...............................................        37,817 (525-               6               0               9              11                 0
                                                            100,000 *)
106...............................................        42,513 (525-               3               0               5              11                 0
                                                            100,000 *)
100...............................................        43,367 (525-               1               0               2               8                 0
                                                            100,000 *)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: dB re: 1 [micro]Pa = decibels referenced to 1 micropascal, MF = mid-frequency.
* Indicates maximum range to which acoustic model was run, a distance of approximately 100 km from the sound source. Cells are shaded if the mean range
  value for the specified received level exceeds the distance cutoff range for a particular hearing group. Any impacts within the cutoff range for a
  criteria group are included in the estimated impacts. Cut-off ranges in this table are for activities with high source levels and/or multiple
  platforms (see Table 12 for behavioral cut-off distances).


Table 16--Ranges to Estimated Level B Harassment by Behavioral Disturbance for Sonar Bin MF5 Over a Representative Range of Environments Within the NWTT
                                                                       Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Average range (m)    Probability of Level B harassment by behavioral disturbance for Sonar bin MF5
                                                     with minimum and  ---------------------------------------------------------------------------------
       Received level  (dB re: 1 [micro]Pa)          maximum values in
                                                        parentheses       Odontocete       Mysticete       Pinniped      Beaked whale    Harbor porpoise
--------------------------------------------------------------------------------------------------------------------------------------------------------
196...............................................             0 (0-0)             100             100             100             100               100
190...............................................             1 (0-3)             100              98              99             100               100
184...............................................             5 (0-7)              99              88              98             100               100
178...............................................           14 (0-18)              97              59              92             100               100
172...............................................           29 (0-35)              91              30              76              99               100
166...............................................           58 (0-70)              78              20              48              97               100
160...............................................         127 (0-280)              58              18              27              93               100
154...............................................       375 (0-1,000)              40              17              18              83               100
148...............................................     799 (490-1,775)              29              16              16              66               100
142...............................................   1,677 (600-3,525)              25              13              15              45               100
136...............................................   2,877 (675-7,275)              23               9              15              28               100
130...............................................  4,512 (700-12,775)              20               5              15              18               100
124...............................................  6,133 (700-19,275)              17               2              14              14               100
118...............................................  7,880 (700-26,275)              12               1              13              12                 0
112...............................................  9,673 (700-33,525)               6               0               9              11                 0
106...............................................        12,095 (700-               3               0               5              11                 0
                                                               45,275)
100...............................................        18,664 (700-               1               0               2               8                 0
                                                               48,775)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: dB re: 1 [micro]Pa = decibels referenced to 1 micropascal, MF = mid-frequency.
* Cells are shaded if the mean range value for the specified received level exceeds the distance cutoff range for a particular hearing group. Any
  impacts within the cutoff range for a criteria group are included in the estimated impacts. Cut-off ranges in this table are for activities with high
  source levels and/or multiple platforms (see Table 12 for behavioral cut-off distances).


[[Page 72384]]


 Table 17--Ranges to Estimated Take by Level B Harassment by Behavioral Disturbance for Sonar Bin HF4 Over a Representative Range of Environments Within
                                                                   the NWTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Average range (m)    Probability of Level B harassment by behavioral disturbance for Sonar bin HF4
                                                     with minimum and  ---------------------------------------------------------------------------------
       Received level  (dB re: 1 [micro]Pa)          maximum values in
                                                        parentheses       Odontocete       Mysticete       Pinniped      Beaked whale    Harbor porpoise
--------------------------------------------------------------------------------------------------------------------------------------------------------
196...............................................             4 (0-7)             100             100             100             100               100
190...............................................           10 (0-16)             100              98              99             100               100
184...............................................           20 (0-40)              99              88              98             100               100
178...............................................           42 (0-85)              97              59              92             100               100
172...............................................          87 (0-270)              91              30              76              99               100
166...............................................         177 (0-650)              78              20              48              97               100
160...............................................        338 (25-825)              58              18              27              93               100
154...............................................      577 (55-1,275)              40              17              18              83               100
148...............................................      846 (60-1,775)              29              16              16              66               100
142...............................................    1,177 (60-2,275)              25              13              15              45               100
136...............................................    1,508 (60-3,025)              23               9              15              28               100
130...............................................    1,860 (60-3,525)              20               5              15              18               100
124...............................................    2,202 (60-4,275)              17               2              14              14               100
118...............................................    2,536 (60-4,775)              12               1              13              12                 0
112...............................................    2,850 (60-5,275)               6               0               9              11                 0
106...............................................    3,166 (60-6,025)               3               0               5              11                 0
100...............................................    3,470 (60-6,775)               1               0               2               8                 0
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: dB re: 1 [micro]Pa = decibels referenced to 1 micropascal, MF = mid-frequency.

Explosives
    Phase III explosive thresholds for Level B harassment by behavioral 
disturbance for marine mammals is the hearing groups' TTS threshold 
minus 5 dB (see Table 18 below and Table 11 for the TTS thresholds for 
explosives) for events that contain multiple impulses from explosives 
underwater. This was the same approach as taken in Phase II for 
explosive analysis. See the Criteria and Thresholds for U.S. Navy 
Acoustic and Explosive Effects Analysis (Phase III) report (U.S. 
Department of the Navy, 2017c) for detailed information on how the 
criteria and thresholds were derived. NMFS continues to concur that 
this approach represents the best available science for determining 
impacts to marine mammals from explosives.

  Table 18--Thresholds for Level B Harassment by Behavioral Disturbance
                    for Explosives for Marine Mammals
------------------------------------------------------------------------
                                  Functional hearing
            Medium                       group           SEL (weighted)
------------------------------------------------------------------------
Underwater....................  Low-frequency                        163
                                 cetaceans.
Underwater....................  Mid-frequency                        165
                                 cetaceans.
Underwater....................  High-frequency                       135
                                 cetaceans.
Underwater....................  Phocids...............               165
Underwater....................  Otariids..............               183
------------------------------------------------------------------------
Note: Weighted SEL thresholds in dB re: 1 [mu]Pa\2\s underwater.

Navy's Acoustic Effects Model

    The Navy's Acoustic Effects Model calculates sound energy 
propagation from sonar and other transducers and explosives during 
naval activities and the sound received by animat dosimeters. Animat 
dosimeters are virtual representations of marine mammals distributed in 
the area around the modeled naval activity and each dosimeter records 
its individual sound ``dose.'' The model bases the distribution of 
animats over the NWTT Study Area on the density values in the Navy 
Marine Species Density Database and distributes animats in the water 
column proportional to the known time that species spend at varying 
depths.
    The model accounts for environmental variability of sound 
propagation in both distance and depth when computing the sound level 
received by the animats. The model conducts a statistical analysis 
based on multiple model runs to compute the estimated effects on 
animals. The number of animats that exceed the thresholds for effects 
is tallied to provide an estimate of the number of marine mammals that 
could be affected.
    Assumptions in the Navy model intentionally err on the side of 
overestimation when there are unknowns. Naval activities are modeled as 
though they would occur regardless of proximity to marine mammals, 
meaning that no mitigation is considered (i.e., no power down or shut 
down modeled) and without any avoidance of the activity by the animal. 
The final step of the quantitative analysis of acoustic effects is to 
consider the implementation of mitigation and the possibility that 
marine mammals would avoid continued or repeated sound exposures. For 
more information on this process, see the discussion in the Take 
Requests subsection below. Many explosions from ordnance such as bombs 
and missiles actually occur upon impact with above-water targets. 
However, for this analysis, sources such as these were modeled as 
exploding underwater, which overestimates the amount of explosive and 
acoustic energy entering the water.
    The model estimates the impacts caused by individual training and 
testing exercises. During any individual modeled event, impacts to 
individual animats are considered over 24-hour periods. The animats do 
not represent actual animals, but rather they represent a distribution 
of animals based on density and abundance data, which

[[Page 72385]]

allows for a statistical analysis of the number of instances that 
marine mammals may be exposed to sound levels resulting in an effect. 
Therefore, the model estimates the number of instances in which an 
effect threshold was exceeded over the course of a year, but does not 
estimate the number of individual marine mammals that may be impacted 
over a year (i.e., some marine mammals could be impacted several times, 
while others would not experience any impact). A detailed explanation 
of the Navy's Acoustic Effects Model is provided in the technical 
report Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: 
Methods and Analytical Approach for Phase III Training and Testing 
(U.S. Department of the Navy, 2018).

Range to Effects

    The following section provides range to effects for sonar and other 
active acoustic sources as well as explosives to specific acoustic 
thresholds determined using the Navy Acoustic Effects Model. Marine 
mammals exposed within these ranges for the shown duration are 
predicted to experience the associated effect. Range to effects is 
important information in not only predicting acoustic impacts, but also 
in verifying the accuracy of model results against real-world 
situations and determining adequate mitigation ranges to avoid higher 
level effects, especially physiological effects to marine mammals.
Sonar
    The ranges to received sound levels in 6-dB steps from five 
representative sonar bins and the percentage of the total number of 
animals that may exhibit a significant behavioral response (and 
therefore Level B harassment) under each BRF are shown in Tables 13 
through 17 above, respectively. See Chapter 6, Section 6.4.2.1 (Methods 
for Analyzing Impacts from Sonars and Other Transducers) of the Navy's 
rulemaking/LOA application for additional details on the derivation and 
use of the BRFs, thresholds, and the cutoff distances that are used to 
identify Level B harassment by behavioral disturbance. NMFS has 
reviewed the range distance to effect data provided by the Navy and 
concurs with the analysis.
    The ranges to PTS for five representative sonar systems for an 
exposure of 30 seconds is shown in Table 19 relative to the marine 
mammal's functional hearing group. This period (30 seconds) was chosen 
based on examining the maximum amount of time a marine mammal would 
realistically be exposed to levels that could cause the onset of PTS 
based on platform (e.g., ship) speed and a nominal animal swim speed of 
approximately 1.5 m per second. The ranges provided in the table 
include the average range to PTS, as well as the range from the minimum 
to the maximum distance at which PTS is possible for each hearing 
group.

 Table 19--Range to Permanent Threshold Shift (Meters) for Five Representative Sonar Systems Over a Representative Range of Environments Within the NWTT
                                                                       Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                             Approximate range in meters for pts from 30 second exposure \1\
                         Hearing group                         -----------------------------------------------------------------------------------------
                                                                  Sonar bin HF4     Sonar bin LF4     Sonar bin MF1     Sonar bin MF4     Sonar bin MF5
--------------------------------------------------------------------------------------------------------------------------------------------------------
High-frequency cetaceans......................................        38 (22-85)           0 (0-0)      195 (80-330)        30 (30-40)          9 (8-11)
Low-frequency cetaceans.......................................           0 (0-0)           2 (1-3)       67 (60-110)        15 (15-17)           0 (0-0)
Mid-frequency cetaceans.......................................           1 (0-3)           0 (0-0)        16 (16-19)           3 (3-3)           0 (0-0)
Otariids......................................................           0 (0-0)           0 (0-0)           6 (6-6)           0 (0-0)           0 (0-0)
Phocids.......................................................           0 (0-0)           0 (0-0)        46 (45-75)        11 (11-12)           0 (0-0)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ PTS ranges extend from the sonar or other active acoustic sound source to the indicated distance. The average range to PTS is provided as well as
  the range from the estimated minimum to the maximum range to PTS in parentheses.

    The tables below illustrate the range to TTS for 1, 30, 60, and 120 
seconds from five representative sonar systems (see Tables 20 through 
24).

     Table 20--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin LF4 Over a Representative Range of
                                     Environments Within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
                                                           Approximate TTS ranges (meters) \1\
                                       -------------------------------------------------------------------------
             Hearing group                                            Sonar bin LF4
                                       -------------------------------------------------------------------------
                                            1 second         30 seconds         60 seconds        120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans..............           0 (0-0)           0 (0-0)            0 (0-0)            1 (0-1)
Low-frequency cetaceans...............        22 (19-30)       32 (25-230)        41 (30-230)        61 (45-100)
Mid-frequency cetaceans...............           0 (0-0)           0 (0-0)            0 (0-0)            0 (0-0)
Otariids..............................           0 (0-0)           0 (0-0)            0 (0-0)            0 (0-0)
Phocids...............................           2 (1-3)           4 (3-4)            4 (4-5)            7 (6-9)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the NWTT Study Area. The
  zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
  range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
  parentheses.


     Table 21--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin MF1 Over a Representative Range of
                                     Environments Within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
                                                           Approximate TTS ranges (meters) \1\
                                       -------------------------------------------------------------------------
             Hearing group                                            Sonar bin MF1
                                       -------------------------------------------------------------------------
                                            1 second         30 seconds         60 seconds        120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans..............  2,466 (80-6,275)  2,466 (80-6,275)  3,140 (80-10,275)  3,740 (80-13,525)
Low-frequency cetaceans...............  1,054 (80-2,775)  1,054 (80-2,775)   1,480 (80-4,525)   1,888 (80-5,275)
Mid-frequency cetaceans...............      225 (80-380)      225 (80-380)       331 (80-525)       411 (80-700)

[[Page 72386]]

 
Otariids..............................       67 (60-110)       67 (60-110)       111 (80-170)       143 (80-250)
Phocids...............................    768 (80-2,025)    768 (80-2,025)   1,145 (80-3,275)   1,388 (80-3,775)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the NWTT Study Area. The
  zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
  range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
  parentheses.
Note: Ranges for 1 second and 30 second periods are identical for Bin MF1 because this system nominally pings
  every 50 seconds; therefore, these periods encompass only a single ping.


     Table 22--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin MF4 Over a Representative Range of
                                     Environments within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
                                                           Approximate TTS ranges (meters)\1\
                                       -------------------------------------------------------------------------
             Hearing group                                            Sonar bin MF4
                                       -------------------------------------------------------------------------
                                            1 second         30 seconds         60 seconds        120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans..............     279 (220-600)   647 (420-1,275)    878 (500-1,525)  1,205 (525-2,275)
Low-frequency cetaceans...............       87 (85-110)     176 (130-320)      265 (190-575)      477 (290-975)
Mid-frequency cetaceans...............        22 (22-25)        35 (35-45)         50 (45-55)         71 (70-85)
Otariids..............................           8 (8-8)        15 (15-17)         19 (19-23)         25 (25-30)
Phocids...............................        66 (65-80)     116 (110-200)      173 (150-300)      303 (240-675)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the NWTT Study Area. The
  zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
  range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
  parentheses.


     Table 23--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin MF5 Over a Representative Range of
                                     Environments Within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
                                                           Approximate TTS ranges (meters) \1\
                                       -------------------------------------------------------------------------
             Hearing group                                            Sonar nin MF5
                                       -------------------------------------------------------------------------
                                            1 second         30 seconds         60 seconds        120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans..............     115 (110-180)     115 (110-180)      174 (150-390)      292 (210-825)
Low-frequency cetaceans...............        11 (10-13)        11 (10-13)         17 (16-19)         24 (23-25)
Mid-frequency cetaceans...............           6 (0-9)           6 (0-9)         12 (11-14)         18 (17-22)
Otariids..............................           0 (0-0)           0 (0-0)            0 (0-0)            0 (0-0)
Phocids...............................          9 (8-11)          9 (8-11)         15 (14-17)         22 (21-25)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the NWTT Study Area. The
  zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
  range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
  parentheses.


     Table 24--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin HF4 Over a Representative Range of
                                     Environments Within the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
                                                           Approximate TTS ranges (meters) \1\
                                       -------------------------------------------------------------------------
             Hearing group                                            Sonar bin HF4
                                       -------------------------------------------------------------------------
                                            1 second         30 seconds         60 seconds        120 seconds
----------------------------------------------------------------------------------------------------------------
High-frequency cetaceans..............      236 (60-675)      387 (60-875)     503 (60-1,025)     637 (60-1,275)
Low-frequency cetaceans...............           2 (0-3)           3 (1-6)            5 (3-8)           8 (5-12)
Mid-frequency cetaceans...............         12 (7-20)        21 (12-40)         29 (17-60)         43 (24-90)
Otariids..............................           0 (0-0)           0 (0-0)            0 (0-0)            1 (0-1)
Phocids...............................           3 (0-5)          6 (4-10)           9 (5-15)          14 (8-25)
----------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the NWTT Study Area. The
  zone in which animals are expected to suffer TTS extends from onset-PTS to the distance indicated. The average
  range to TTS is provided as well as the range from the estimated minimum to the maximum range to TTS in
  parentheses.

Explosives
    The following section provides the range (distance) over which 
specific physiological or behavioral effects are expected to occur 
based on the explosive criteria (see Chapter 6, Section 6.5.2 (Impacts 
from Explosives) of the Navy's rulemaking/LOA application and the 
Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects 
Analysis (Phase III) report (U.S. Department of the Navy, 2017c)) and 
the explosive propagation calculations from the Navy Acoustic Effects 
Model (see Chapter 6, Section 6.5.2.2 (Impact Ranges for Explosives) of 
the Navy's rulemaking/LOA application). The range to effects are shown 
for a range of explosive bins, from E1 (up to 0.25 lb net explosive 
weight) to E11 (greater than 500 lb to 650 lb net explosive weight) 
(Tables 25 through 31). Ranges are determined by modeling the distance 
that noise from

[[Page 72387]]

an explosion would need to propagate to reach exposure level thresholds 
specific to a hearing group that would cause behavioral response (to 
the degree of Level B harassment), TTS, PTS, and non-auditory injury. 
Ranges are provided for a representative source depth and cluster size 
for each bin. For events with multiple explosions, sound from 
successive explosions can be expected to accumulate and increase the 
range to the onset of an impact based on SEL thresholds. Ranges to non-
auditory injury and mortality are shown in Tables 30 and 31, 
respectively. NMFS has reviewed the range distance to effect data 
provided by the Navy and concurs with the analysis. For additional 
information on how ranges to impacts from explosions were estimated, 
see the technical report Quantifying Acoustic Impacts on Marine Mammals 
and Sea Turtles: Methods and Analytical Approach for Phase III Training 
and Testing (U.S. Navy, 2018).
    Table 25 shows the minimum, average, and maximum ranges to onset of 
auditory and likely behavioral effects that rise to the level of Level 
B harassment for high-frequency cetaceans based on the developed 
thresholds.

       Table 25--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Harassment by Behavioral Disturbance for High-Frequency Cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                              Range to effects for explosives: high-frequency cetaceans \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Source depth
                    Bin                           (m)           Cluster size               PTS                    TTS             Behavioral disturbance
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1........................................             0.1                     1         361 (350-370)      1,108 (1,000-1,275)      1,515 (1,025-2,025)
                                            ..............                    18     1,002 (925-1,025)      2,404 (1,275-4,025)      3,053 (1,275-5,025)
E2........................................             0.1                     1         439 (420-450)      1,280 (1,025-1,775)      1,729 (1,025-2,525)
                                            ..............                     5         826 (775-875)      1,953 (1,275-3,025)       2,560(1,275-4,275)
E3........................................              10                     1      1,647(160-3,525)       2,942 (160-10,275)       3,232 (160-12,275)
                                            ..............                    12     3,140 (160-9,525)       3,804 (160-17,525)       3,944 (160-21,775)
                                                     18.25                     1       684 (550-1,000)      2,583 (1,025-5,025)      4,217 (1,525-7,525)
                                            ..............                    12   1,774 (1,025-3,775)     5,643 (1,775-10,025)     7,220 (2,025-13,275)
E4........................................              10                     2     1,390 (950-3,025)      5,250 (2,275-8,275)     7,004 (2,775-11,275)
                                                        30                     2     1,437 (925-2,775)      4,481 (1,525-7,775)     5,872 (2,775-10,525)
                                                        70                     2     1,304 (925-2,275)      3,845 (2,525-7,775)      5,272 (3,525-9,525)
                                                        90                     2     1,534 (900-2,525)      5,115 (2,525-7,525)     6,840 (3,275-10,275)
E5........................................             0.1                     1       940 (850-1,025)      2,159 (1,275-3,275)      2,762 (1,275-4,275)
                                            ..............                    20   1,930 (1,275-2,775)      4,281 (1,775-6,525)      5,176 (2,025-7,775)
E7........................................              10                     1   2,536 (1,275-3,775)     6,817 (2,775-11,025)     8,963 (3,525-14,275)
                                                        30                     1   1,916 (1,025-4,275)     5,784 (2,775-10,525)     7,346 (2,775-12,025)
E8........................................           45.75                     1   1,938 (1,275-4,025)     4,919 (1,775-11,275)     5,965 (2,025-15,525)
E10.......................................             0.1                     1   1,829 (1,025-2,775)      4,166 (1,775-6,025)      5,023 (2,025-7,525)
E11.......................................            91.4                     1   3,245 (2,025-6,775)     6,459 (2,525-15,275)     7,632 (2,775-19,025)
                                                       200                     1   3,745 (3,025-5,025)     7,116 (4,275-11,275)     8,727 (5,025-15,025)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral disturbance thresholds are depicted above the minimum and maximum distances which are in
  parentheses. Values depict the range produced by SEL hearing threshold criteria levels.

    Table 26 shows the minimum, average, and maximum ranges to onset of 
auditory and likely behavioral effects that rise to the level of Level 
B harassment for low-frequency cetaceans based on the developed 
thresholds.

        Table 26--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Harassment by Behavioral Disturbance for Low-Frequency Cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                              Range to effects for explosives: low-frequency cetaceans \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Source depth
                    Bin                           (m)           Cluster size               PTS                    TTS             Behavioral disturbance
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1........................................             0.1                     1            52 (50-55)            221 (120-250)            354 (160-420)
                                            ..............                    18         177 (110-200)            656 (230-875)          836 (280-1,025)
E2........................................             0.1                     1            66 (55-70)            276 (140-320)            432 (180-525)
                                            ..............                     5          128 (90-140)            512 (200-650)            735 (250-975)
E3........................................              10                     1         330 (160-550)        1,583 (160-4,025)        2,085 (160-7,525)
                                            ..............                    12     1,177 (160-2,775)       2,546 (160-11,775)       2,954 (160-17,025)
18.25.....................................  ..............                     1         198 (180-220)        1,019 (490-2,275)        1,715 (625-4,025)
                                            ..............                    12       646 (390-1,025)        3,723 (800-9,025)     6,399 (1,025-46,525)
E4........................................              10                     2         462 (400-600)      3,743 (2,025-7,025)     6,292 (2,525-13,275)
                                                        30                     2         527 (330-950)      3,253 (1,775-4,775)      5,540 (2,275-8,275)
                                                        70                     2         490 (380-775)      3,026 (1,525-4,775)      5,274 (2,275-7,775)
                                                        90                     2         401 (360-500)      3,041 (1,275-4,525)      5,399 (1,775-9,275)
E5........................................             0.1                     1         174 (100-260)            633 (220-850)          865 (270-1,275)
                                            ..............                    20         550 (200-700)        1,352 (420-2,275)        2,036 (700-4,275)
E7........................................              10                     1     1,375 (875-2,525)     7,724 (3,025-15,025)    11,787 (4,525-25,275)
                                                        30                     1     1,334 (675-2,025)     7,258 (2,775-11,025)    11,644 (4,525-24,275)
E8........................................           45.75                     1      1,227 575-2,525)     3,921 (1,025-17,275)      7,961(1,275-48,525)
E10.......................................             0.1                     1         546 (200-700)        1,522 (440-5,275)       3,234 (850-30,525)
E11.......................................            91.4                     1     2,537 (950-5,525)    11,249 (1,775-50,775)    37,926 (6,025-94,775)

[[Page 72388]]

 
                                                       200                     1   2,541 (1,525-4,775)     7,407 (2,275-43,275)    42,916 (6,275-51,275)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral disturbance thresholds are depicted above the minimum and maximum distances which are in
  parentheses. Values depict the range produced by SEL hearing threshold criteria levels.

    Table 27 shows the minimum, average, and maximum ranges to onset of 
auditory and likely behavioral effects that rise to the level of Level 
B harassment for mid-frequency cetaceans based on the developed 
thresholds.

        Table 27--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Harassment by Behavioral Disturbance for Mid-Frequency Cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                              Range to effects for explosives: Mid-frequency cetaceans \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Source depth
                    Bin                           (m)           Cluster size               PTS                    TTS             Behavioral disturbance
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1........................................             0.1                     1            25 (25-25)            118 (110-120)            203 (190-210)
                                            ..............                    18           96 (90-100)            430 (410-440)            676 (600-700)
E2........................................             0.1                     1            30 (30-30)            146 (140-150)            246 (230-250)
                                            ..............                     5            64 (60-65)            298 (290-300)            493 (470-500)
E3........................................              10                     1           61 (50-100)            512 (160-750)          928 (160-2,025)
                                            ..............                    12         300 (160-625)        1,604 (160-3,525)        2,085 (160-5,525)
                                                     18.25                     1            40 (35-40)            199 (180-280)            368 (310-800)
                                            ..............                    12         127 (120-130)          709 (575-1,000)        1,122 (875-2,525)
E4........................................              10                     2            73 (70-75)            445 (400-575)          765 (600-1,275)
                                                        30                     2            71 (65-90)          554 (320-1,025)          850 (525-1,775)
                                                        70                     2            63 (60-85)            382 (320-675)          815 (525-1,275)
                                                        90                     2            59 (55-85)            411 (310-900)          870 (525-1,275)
E5........................................             0.1                     1            79 (75-80)            360 (350-370)            575 (525-600)
                                            ..............                    20         295 (280-300)          979 (800-1,275)        1,442 (925-1,775)
E7........................................              10                     1         121 (110-130)          742 (575-1,275)        1,272 (875-2,275)
                                                        30                     1         111 (100-130)          826 (500-1,775)        1,327 (925-2,275)
E8........................................           45.75                     1         133 (120-170)          817 (575-1,525)        1,298 (925-2,525)
E10.......................................             0.1                     1         273 (260-280)          956 (775-1,025)        1,370 (900-1,775)
E11.......................................            91.4                     1         242 (220-310)      1,547 (1,025-3,025)      2,387 (1,275-4,025)
                                                       200                     1         209 (200-300)      1,424 (1,025-2,025)      2,354 (1,525-3,775)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral disturbance thresholds are depicted above the minimum and maximum distances which are in
  parentheses. Values depict the range produced by SEL hearing threshold criteria levels.

    Table 28 shows the minimum, average, and maximum ranges to onset of 
auditory and likely behavioral effects that rise to the level of Level 
B harassment for otariid pinnipeds based on the developed thresholds.

               Table 28--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Harassment by Behavioral Disturbance for Otariids
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Range to effects for explosives: Otariids \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Source depth                             Range to PTS                                 Range to behavioral
                    Bin                        (meters)         Cluster size            (meters)         Range to TTS (meters)           (meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1........................................             0.1                     1               7 (7-8)               34 (30-35)               58 (55-60)
                                            ..............                    18            25 (25-25)            124 (120-130)            208 (200-210)
E2........................................             0.1                     1              9 (9-10)               43 (40-45)               72 (70-75)
                                            ..............                     5            19 (19-20)               88 (85-90)            145 (140-150)
E3........................................              10                     1            21 (18-25)            135 (120-210)            250 (160-370)
                                            ..............                    12           82 (75-100)            551 (160-875)          954 (160-2,025)
                                                     18.25                     1            15 (15-15)               91 (85-95)            155 (150-160)
                                            ..............                    12            53 (50-55)            293 (260-430)            528 (420-825)
E4........................................              10                     2            30 (30-30)            175 (170-180)            312 (300-350)
                                                        30                     2            25 (25-25)            176 (160-250)            400 (290-750)
                                                        70                     2            26 (25-35)            148 (140-200)            291 (250-400)
                                                        90                     2            26 (25-35)            139 (130-190)            271 (250-360)
E5........................................             0.1                     1            25 (24-25)            111 (110-120)            188 (180-190)
                                            ..............                    20            93 (90-95)            421 (390-440)            629 (550-725)
E7........................................              10                     1            60 (60-60)            318 (300-360)            575 (500-775)

[[Page 72389]]

 
                                                        30                     1            53 (50-65)            376 (290-700)          742 (500-1,025)
E8........................................           45.75                     1            55 (55-55)            387 (310-750)          763 (525-1,275)
E10.......................................             0.1                     1            87 (85-90)            397 (370-410)            599 (525-675)
E11.......................................            91.4                     1         100 (100-100)          775 (550-1,275)        1,531 (900-3,025)
                                                       200                     1           94 (90-100)            554 (525-700)        1,146 (900-1,525)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral disturbance thresholds are depicted above the minimum and maximum distances which are in
  parentheses. Values depict the range produced by SEL hearing threshold criteria levels.

    Table 29 shows the minimum, average, and maximum ranges to onset of 
auditory and likely behavioral effects that rise to the level of Level 
B harassment for phocid pinnipeds based on the developed thresholds.

                Table 29--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Harassment by Behavioral Disturbance for Phocids
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Range to Effects for Explosives: Phocids \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Source depth                             Range to PTS                                 Range to behavioral
                    Bin                        (meters)         Cluster size            (meters)         Range to TTS  (meters)          (meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1........................................             0.1                     1            47 (45-50)            219 (210-230)            366 (350-370)
                                            ..............                    18         171 (160-180)            764 (725-800)      1,088 (1,025-1,275)
E2........................................             0.1                     1            59 (55-60)            273 (260-280)            454 (440-460)
                                            ..............                     5         118 (110-120)            547 (525-550)            881 (825-925)
E3........................................              10                     1         185 (160-260)        1,144 (160-2,775)        1,655 (160-4,525)
                                            ..............                    12       760 (160-1,525)        2,262 (160-8,025)       2,708 (160-12,025)
                                                     18.25                     1         112 (110-120)            628 (500-950)        1,138 (875-2,525)
                                            ..............                    12         389 (330-625)      2,248 (1,275-4,275)      4,630 (1,275-8,525)
E4........................................              10                     2         226 (220-240)        1,622 (950-3,275)      3,087 (1,775-5,775)
                                                        30                     2         276 (200-600)      1,451 (1,025-2,275)      2,611 (1,775-4,275)
                                                        70                     2         201 (180-280)      1,331 (1,025-1,775)      2,403 (1,525-3,525)
                                                        90                     2         188 (170-270)        1,389 (975-2,025)      2,617 (1,775-3,775)
E5........................................             0.1                     1         151 (140-160)            685 (650-700)        1,002 (950-1,025)
                                            ..............                    20         563 (550-575)      1,838 (1,275-2,275)      2,588 (1,525-3,525)
E7........................................              10                     1         405 (370-490)      3,185 (1,775-6,025)     5,314 (2,275-11,025)
                                                        30                     1         517 (370-875)      2,740 (1,775-4,275)      4,685 (3,025-7,275)
E8........................................           45.75                     1       523 (390-1,025)      2,502 (1,525-6,025)     3,879 (2,025-10,275)
E10.......................................             0.1                     1         522 (500-525)      1,800 (1,275-2,275)      2,470 (1,525-3,275)
E11.......................................            91.4                     1     1,063 (675-2,275)     5,043 (2,775-10,525)     7,371 (3,275-18,025)
                                                       200                     1         734 (675-850)      5,266 (3,525-9,025)     7,344 (5,025-12,775)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral disturbance thresholds are depicted above the minimum and maximum distances which are in
  parentheses. Values depict the range produced by SEL hearing threshold criteria levels.

    Table 30 shows the minimum, average, and maximum ranges due to 
varying propagation conditions to non-auditory injury as a function of 
animal mass and explosive bin (i.e., net explosive weight). Ranges to 
gastrointestinal tract injury typically exceed ranges to slight lung 
injury; therefore, the maximum range to effect is not mass-dependent. 
Animals within these water volumes would be expected to receive minor 
injuries at the outer ranges, increasing to more substantial injuries, 
and finally mortality as an animal approaches the detonation point.

Table 30--Ranges \1\ to 50 Percent to Non-Auditory Injury for All Marine
                          Mammal Hearing Groups
------------------------------------------------------------------------
                                            Range to non-auditory injury
                    Bin                              (meters) \1\
------------------------------------------------------------------------
E1........................................                    12 (11-13)
E2........................................                    16 (15-16)
E3........................................                    25 (25-45)
E4........................................                    31 (23-50)
E5........................................                    40 (40-40)
E7........................................                  104 (80-190)
E8........................................                 149 (130-210)
E10.......................................                 153 (100-400)

[[Page 72390]]

 
E11.......................................                 419 (350-725)
------------------------------------------------------------------------
\1\ Distances in meters (m). Average distance is shown with the minimum
  and maximum distances due to varying propagation environments in
  parentheses.
Note: All ranges to non-auditory injury within this table are driven by
  gastrointestinal tract injury thresholds regardless of animal mass.

    Ranges to mortality, based on animal mass, are shown in Table 31 
below.

                 Table 31--Ranges \1\ to 50 Percent to Mortality Risk for All Marine Mammal Hearing Groups as a Function of Animal Mass
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Range to mortality (meters) for various animal mass intervals (kg) \1\
                           Bin                           -----------------------------------------------------------------------------------------------
                                                               10 kg          250 kg         1,000 kg        5,000 kg        25,000 kg       72,000 kg
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1......................................................         3 (2-3)         1 (0-3)         0 (0-0)         0 (0-0)         0 (0-0)         0 (0-0)
E2......................................................         4 (3-5)         2 (1-3)         1 (0-1)         0 (0-0)         0 (0-0)         0 (0-0)
E3......................................................       10 (9-20)        5 (3-20)         2 (1-5)         0 (0-3)         0 (0-1)         0 (0-1)
E4......................................................      13 (11-19)        7 (4-13)         3 (2-4)         2 (1-3)         1 (1-1)         1 (0-1)
E5......................................................      13 (11-15)        7 (4-11)         3 (3-4)         2 (1-3)         1 (1-1)         1 (0-1)
E7......................................................      49 (40-80)      27 (15-60)      13 (10-20)        9 (5-12)         4 (4-6)         3 (2-4)
E8......................................................      65 (60-75)      34 (22-55)      17 (14-20)       11 (9-13)         6 (5-6)         5 (4-5)
E10.....................................................      43 (40-50)      25 (16-40)      13 (11-16)        9 (7-11)         5 (4-6)         4 (3-4)
E11.....................................................    185 (90-230)     90 (30-170)      40 (30-50)      28 (23-30)      15 (13-16)       11 (9-13)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to mortality is depicted above the minimum and maximum distances, which are in parentheses.

Marine Mammal Density

    A quantitative analysis of impacts on a species or stock requires 
data on their abundance and distribution that may be affected by 
anthropogenic activities in the potentially impacted area. The most 
appropriate metric for this type of analysis is density, which is the 
number of animals present per unit area. Marine species density 
estimation requires a significant amount of effort to both collect and 
analyze data to produce a reasonable estimate. Unlike surveys for 
terrestrial wildlife, many marine species spend much of their time 
submerged, and are not easily observed. In order to collect enough 
sighting data to make reasonable density estimates, multiple 
observations are required, often in areas that are not easily 
accessible (e.g., far offshore). Ideally, marine mammal species 
sighting data would be collected for the specific area and time period 
(e.g., season) of interest and density estimates derived accordingly. 
However, in many places, poor weather conditions and high sea states 
prohibit the completion of comprehensive visual surveys.
    For most cetacean species, abundance is estimated using line-
transect surveys or mark-recapture studies (e.g., Barlow, 2010; Barlow 
and Forney, 2007; Calambokidis et al., 2008). The result provides one 
single density estimate value for each species across broad geographic 
areas. This is the general approach applied in estimating cetacean 
abundance in NMFS' SARs. Although the single value provides a good 
average estimate of abundance (total number of individuals) for a 
specified area, it does not provide information on the species 
distribution or concentrations within that area, and it does not 
estimate density for other timeframes or seasons that were not 
surveyed. More recently, spatial habitat modeling developed by NMFS' 
Southwest Fisheries Science Center has been used to estimate cetacean 
densities (Barlow et al., 2009; Becker et al., 2010, 2012a, b, c, 2014, 
2016, 2017, 2020; Ferguson et al., 2006a; Forney et al., 2012, 2015; 
Redfern et al., 2006). These models estimate cetacean density as a 
continuous function of habitat variables (e.g., sea surface 
temperature, seafloor depth, etc.) and thus allow predictions of 
cetacean densities on finer spatial scales than traditional line-
transect or mark recapture analyses and for areas that have not been 
surveyed. Within the geographic area that was modeled, densities can be 
predicted wherever these habitat variables can be measured or 
estimated.
    Ideally, density data would be available for all species throughout 
the study area year-round, in order to best estimate the impacts of 
Navy activities on marine species. However, in many places, ship 
availability, lack of funding, inclement weather conditions, and high 
sea states prevent the completion of comprehensive year-round surveys. 
Even with surveys that are completed, poor conditions may result in 
lower sighting rates for species that would typically be sighted with 
greater frequency under favorable conditions. Lower sighting rates 
preclude having an acceptably low uncertainty in the density estimates. 
A high level of uncertainty, indicating a low level of confidence in 
the density estimate, is typical for species that are rare or difficult 
to sight. In areas where survey data are limited or non-existent, known 
or inferred associations between marine habitat features and the likely 
presence of specific species are sometimes used to predict densities in 
the absence of actual animal sightings. Consequently, there is no 
single source of density data for every area, species, and season 
because of the fiscal costs, resources, and effort involved in 
providing enough survey coverage to sufficiently estimate density.
    To characterize marine species density for large oceanic regions, 
the Navy reviews, critically assesses, and prioritizes existing density 
estimates from multiple sources, requiring the development of a 
systematic method for selecting the most appropriate density estimate 
for each combination of

[[Page 72391]]

species/stock, area, and season. The selection and compilation of the 
best available marine species density data resulted in the Navy Marine 
Species Density Database (NMSDD). The Navy vetted all cetacean 
densities with NMFS prior to use in the Navy's acoustic analysis for 
the current NWTT rulemaking process.
    A variety of density data and density models are needed in order to 
develop a density database that encompasses the entirety of the NWTT 
Study Area. Because this data is collected using different methods with 
varying amounts of accuracy and uncertainty, the Navy has developed a 
hierarchy to ensure the most accurate data is used when available. The 
U.S. Navy Marine Species Density Database Phase III for the Northwest 
Training and Testing Study Area (U.S. Department of the Navy, 2019), 
hereafter referred to as the Density Technical Report, describes these 
models in detail and provides detailed explanations of the models 
applied to each species density estimate. The list below describes 
models in order of preference.
    1. Spatial density models are preferred and used when available 
because they provide an estimate with the least amount of uncertainty 
by deriving estimates for divided segments of the sampling area. These 
models (see Becker et al., 2016; Forney et al., 2015) predict spatial 
variability of animal presence as a function of habitat variables 
(e.g., sea surface temperature, seafloor depth, etc.). This model is 
developed for areas, species, and, when available, specific timeframes 
(months or seasons) with sufficient survey data; therefore, this model 
cannot be used for species with low numbers of sightings.
    2. Stratified design-based density estimates use line-transect 
survey data with the sampling area divided (stratified) into sub-
regions, and a density is predicted for each sub-region (see Barlow, 
2016; Becker et al., 2016; Bradford et al., 2017; Campbell et al., 
2014; Jefferson et al., 2014). While geographically stratified density 
estimates provide a better indication of a species' distribution within 
the study area, the uncertainty is typically high because each sub-
region estimate is based on a smaller stratified segment of the overall 
survey effort.
    3. Design-based density estimations use line-transect survey data 
from land and aerial surveys designed to cover a specific geographic 
area (see Carretta et al., 2015). These estimates use the same survey 
data as stratified design-based estimates, but are not segmented into 
sub-regions and instead provide one estimate for a large surveyed area. 
Although relative environmental suitability (RES) models provide 
estimates for areas of the oceans that have not been surveyed using 
information on species occurrence and inferred habitat associations and 
have been used in past density databases, these models were not used in 
the current quantitative analysis.
    The Navy developed a protocol and database to select the best 
available data sources based on species, area, and time (season). The 
resulting Geographic Information System database, used in the NMSDD, 
includes seasonal density values for every marine mammal species 
present within the NWTT Study Area. This database is described in the 
Density Technical Report.
    The Navy describes some of the challenges of interpreting the 
results of the quantitative analysis summarized above and described in 
the Density Technical Report: ``It is important to consider that even 
the best estimate of marine species density is really a model 
representation of the values of concentration where these animals might 
occur. Each model is limited to the variables and assumptions 
considered by the original data source provider. No mathematical model 
representation of any biological population is perfect, and with 
regards to marine mammal biodiversity, any single model method will not 
completely explain the actual distribution and abundance of marine 
mammal species. It is expected that there would be anomalies in the 
results that need to be evaluated, with independent information for 
each case, to support if we might accept or reject a model or portions 
of the model (U.S. Department of the Navy, 2017a).''
    The Navy's estimate of abundance (based on density estimates used 
in the NWTT Study Area) utilizes NMFS' SARs, except for species with 
high site fidelity/smaller home ranges within the NWTT Study Area, 
relative to their geographic distribution (e.g., harbor seals). For 
harbor seals in the inland waters, more up-to-date, site specific 
population estimates were available. For some species, the stock 
assessment for a given species may exceed the Navy's density prediction 
because those species' home range extends beyond the Study Area 
boundaries. For other species, the stock assessment abundance may be 
much less than the number of animals in the Navy's modeling given that 
the NWTT Study Area extends beyond the U.S waters covered by the SAR 
abundance estimate. The primary source of density estimates are 
geographically specific survey data and either peer-reviewed line-
transect estimates or habitat-based density models that have been 
extensively validated to provide the most accurate estimates possible.
    NMFS coordinated with the Navy in the development of its take 
estimates and concurs that the Navy's approach for density 
appropriately utilizes the best available science. Later, in the 
Analysis and Negligible Impact Determination section, we assess how the 
estimated take numbers compare to stock abundance in order to better 
understand the potential number of individuals impacted.

Take Estimation

    The 2020 NWTT FSEIS/OEIS considered all training and testing 
activities planned to occur in the NWTT Study Area that have the 
potential to result in the MMPA defined take of marine mammals. The 
Navy determined that the three stressors below could result in the 
incidental taking of marine mammals. NMFS has reviewed the Navy's data 
and analysis and determined that it is complete and accurate and agrees 
that the following stressors have the potential to result in takes by 
harassment or serious injury/mortality of marine mammals from the 
Navy's planned activities:
     Acoustics (sonar and other transducers);
     Explosives (explosive shock wave and sound, assumed to 
encompass the risk due to fragmentation); and
     Vessel strike.
    Acoustic and explosive sources have the potential to result in 
incidental takes of marine mammals by harassment and injury. Vessel 
strikes have the potential to result in incidental take from injury, 
serious injury, and/or mortality.
    The quantitative analysis process used for the 2020 NWTT FSEIS/OEIS 
and the Navy's take request in the rulemaking/LOA application to 
estimate potential exposures to marine mammals resulting from acoustic 
and explosive stressors is described above and further detailed in the 
technical report titled Quantifying Acoustic Impacts on Marine Mammals 
and Sea Turtles: Methods and Analytical Approach for Phase III Training 
and Testing (U.S. Department of the Navy, 2018). The Navy Acoustic 
Effects Model (NAEMO) brings together scenario simulations of the 
Navy's activities, sound propagation modeling, and marine mammal 
distribution (based on density and group size) by species to model and 
quantify the exposure of marine mammals above identified thresholds for 
behavioral harassment, TTS, PTS, non-auditory injury, and mortality.

[[Page 72392]]

    NAEMO estimates acoustic and explosive effects without taking 
mitigation into account; therefore, the model overestimates predicted 
impacts on marine mammals within mitigation zones. To account for 
mitigation for marine species in the take estimates, the Navy conducts 
a quantitative assessment of mitigation. The Navy conservatively 
quantifies the manner in which procedural mitigation is expected to 
reduce the risk for model-estimated PTS for exposures to sonars and for 
model-estimated mortality for exposures to explosives, based on species 
sightability, observation area, visibility, and the ability to exercise 
positive control over the sound source. See the proposed rule (85 FR 
33914; June 2, 2020) for a description of the process for assessing the 
effectiveness of procedural mitigation measures, along with the process 
for assessing the potential for animal avoidance. Where the analysis 
indicates mitigation would effectively reduce risk, the model-estimated 
PTS takes are considered reduced to TTS and the model-estimated 
mortalities are considered reduced to injury. For a complete 
explanation of the process for assessing the effects of mitigation, see 
the Navy's rulemaking/LOA application (Section 6: Take Estimates for 
Marine Mammals, and Section 11: Mitigation Measures) and the technical 
report titled Quantifying Acoustic Impacts on Marine Mammals and Sea 
Turtles: Methods and Analytical Approach for Phase III Training and 
Testing (U.S. Department of the Navy, 2018). The extent to which the 
mitigation areas reduce impacts on the affected species is addressed 
qualitatively separately in the Analysis and Negligible Impact 
Determination section.
    NMFS coordinated with the Navy in the development of this 
quantitative method to address the effects of procedural mitigation on 
acoustic and explosive exposures and takes, and NMFS independently 
reviewed and concurs with the Navy that it is appropriate to 
incorporate the quantitative assessment of mitigation into the take 
estimates based on the best available science.
    As a general matter, NMFS does not prescribe the methods for 
estimating take for any applicant, but we review and ensure that 
applicants use the best available science, and methodologies that are 
logical and technically sound. Applicants may use different methods of 
calculating take (especially when using models) and still get to a 
result that is representative of the best available science and that 
allows for a rigorous and accurate evaluation of the effects on the 
affected populations. There are multiple pieces of the Navy take 
estimation methods--propagation models, animat movement models, and 
behavioral thresholds, for example. NMFS evaluates the acceptability of 
these pieces as they evolve and are used in different rules and impact 
analyses. Some of the pieces of the Navy's take estimation process have 
been used in Navy incidental take rules since 2009 and have undergone 
multiple public comment processes; all of them have undergone extensive 
internal Navy review, and all of them have undergone comprehensive 
review by NMFS, which has sometimes resulted in modifications to 
methods or models.
    The Navy uses rigorous review processes (verification, validation, 
and accreditation processes; peer and public review) to ensure the data 
and methodology it uses represent the best available science. For 
instance, the NAEMO model is the result of a NMFS-led Center for 
Independent Experts (CIE) review of the components used in earlier 
models. The acoustic propagation component of the NAEMO model (CASS/
GRAB) is accredited by the Oceanographic and Atmospheric Master Library 
(OAML), and many of the environmental variables used in the NAEMO model 
come from approved OAML databases and are based on in-situ data 
collection. The animal density components of the NAEMO model are base 
products of the NMSDD, which includes animal density components that 
have been validated and reviewed by a variety of scientists from NMFS 
Science Centers and academic institutions. Several components of the 
model, for example the Duke University habitat-based density models, 
have been published in peer reviewed literature. Others like the 
Atlantic Marine Assessment Program for Protected Species, which was 
conducted by NMFS Science Centers, have undergone quality assurance and 
quality control (QA/QC) processes. Finally, the NAEMO model simulation 
components underwent QA/QC review and validation for model parts such 
as the scenario builder, acoustic builder, scenario simulator, etc., 
conducted by qualified statisticians and modelers to ensure accuracy. 
Other models and methodologies have gone through similar review 
processes.
    In summary, we believe the Navy's methods, including the underlying 
NAEMO modeling and the method for incorporating mitigation and 
avoidance, are the most appropriate methods for predicting non-auditory 
injury, PTS, TTS, and behavioral disturbance. But even with the 
consideration of mitigation and avoidance, given some of the more 
conservative components of the methodology (e.g., the thresholds do not 
consider ear recovery between pulses), we would describe the 
application of these methods as identifying the maximum number of 
instances in which marine mammals would be reasonably expected to be 
taken through non-auditory injury, PTS, TTS, or behavioral disturbance.
Summary of Estimated Take by Harassment From Training and Testing 
Activities
    Based on the methods discussed in the previous sections and the 
Navy's model and quantitative assessment of mitigation, the Navy 
provided its take estimate and request for authorization of takes 
incidental to the use of acoustic and explosive sources for training 
and testing activities both annually (based on the maximum number of 
activities that could occur per 12-month period) and over the seven-
year period covered by the Navy's rulemaking/LOA application. The 
following species/stocks present in the NWTT Study Area were modeled by 
the Navy and estimated to have 0 takes of any type from any activity 
source: Eastern North Pacific Northern Resident stock of killer whales, 
Western North Pacific stock of gray whales, and California stock of 
harbor seals. NMFS has reviewed the Navy's data, methodology, and 
analysis and determined that it is complete and accurate. NMFS agrees 
that the estimates for incidental takes by harassment from all sources 
requested for authorization are the maximum number of instances in 
which marine mammals are reasonably expected to be taken.
    For training and testing activities, Tables 32 and 33 summarize the 
Navy's take estimate and request and include the maximum amount of 
Level A harassment and Level B harassment for the seven-year period 
that NMFS concurs is reasonably expected to occur by species and stock. 
Note that take by Level B harassment includes both behavioral 
disturbance and TTS. Tables 6-14-41 (sonar and other transducers) and 
6-56-71 (explosives) in Section 6 of the Navy's rulemaking/LOA 
application provide the comparative amounts of TTS and behavioral 
disturbance for each species and stock annually, noting that if a 
modeled marine mammal was ``taken'' through exposure to both TTS and 
behavioral disturbance in the model, it was recorded as a TTS.

[[Page 72393]]



  Table 32--Annual and Seven-Year Total Species-Specific Take Estimates Authorized From Acoustic and Explosive
                     Sound Source Effects for All Training Activities in the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
                                                              Annual                     7-Year total \1\
            Species                   Stock      ---------------------------------------------------------------
                                                      Level B         Level A         Level B         Level A
----------------------------------------------------------------------------------------------------------------
                                Order Cetacea Suborder Mysticeti (baleen whales)
----------------------------------------------------------------------------------------------------------------
Family Balaenopteridae
 (rorquals):
    Blue whale *..............  Eastern North                  2               0              11               0
                                 Pacific.
    Fin whale *...............  Northeast                      0               0               0               0
                                 Pacific.
                                California,                   54               0             377               0
                                 Oregon,
                                 Washington.
    Sei whale *...............  Eastern North                 30               0             206               0
                                 Pacific.
    Minke whale...............  Alaska..........               0               0               0               0
                                California,                  110               0             767               0
                                 Oregon,
                                 Washington.
    Humpback whale............  Central North                  5               0              31               0
                                 Pacific.
                                California,                    4               0          \2\ 28               0
                                 Oregon,
                                 Washington
                                 [dagger].
Family Eschrichtiidae (gray
 whale):
    Gray whale................  Eastern North                  2               0              10               0
                                 Pacific.
                                Western North                  0               0               0               0
                                 Pacific
                                 [dagger].
----------------------------------------------------------------------------------------------------------------
                                      Suborder Odontoceti (toothed whales)
----------------------------------------------------------------------------------------------------------------
Family Delphinidae (dolphins):
    Bottlenose dolphin........  California,                    5               0              33               0
                                 Oregon, &
                                 Washington,
                                 Offshore.
    Killer whale..............  Alaska Resident.               0               0               0               0
                                Eastern North                 68               0         \2\ 476               0
                                 Pacific
                                 Offshore.
                                Northern                       0               0               0               0
                                 Resident.
                                West Coast                    78               0             538               0
                                 Transient.
                                Southern                       3               0              15               0
                                 Resident
                                 [dagger].
    Northern right whale        California,                7,941               0          55,493               0
     dolphin.                    Oregon,
                                 Washington.
    Pacific white-sided         North Pacific...               0               0               0               0
     dolphin.
                                California,                5,284               0          36,788               0
                                 Oregon,
                                 Washington.
    Risso's dolphin...........  California,                2,286               0          15,972               0
                                 Oregon,
                                 Washington.
    Short-beaked common         California,                1,165               0           8,124               0
     dolphin.                    Oregon,
                                 Washington.
    Short-finned pilot whale..  California,                   57               0             398               0
                                 Oregon,
                                 Washington.
    Striped dolphin...........  California,                  439               0           3,059               0
                                 Oregon,
                                 Washington.
Family Kogiidae (Kogia spp.):
    Kogia whales..............  California,              \3\ 382               0       \3\ 2,665               0
                                 Oregon,
                                 Washington.
Family Phocoenidae
 (porpoises):
    Dall's porpoise...........  Alaska..........               0               0               0               0
                                California,               13,299               8          92,793              48
                                 Oregon,
                                 Washington.
    Harbor porpoise...........  Southeast Alaska               0               0               0               0
                                Northern Oregon/             299               0           2,092               0
                                 Washington
                                 Coast.
                                Northern                      21               0             145               0
                                 California/
                                 Southern Oregon.
                                Washington                12,315              43          79,934             291
                                 Inland Waters.
Family Physeteridae (sperm
 whale):
    Sperm whale *.............  California,                  512               0           3,574               0
                                 Oregon,
                                 Washington.
Family Ziphiidae (beaked
 whales):
    Baird's beaked whale......  California,                  556               0           3,875               0
                                 Oregon,
                                 Washington.
    Cuvier's beaked whale.....  California,                1,462               0          10,209               0
                                 Oregon,
                                 Washington.
    Mesoplodon spp............  California,                  652               0           4,549               0
                                 Oregon,
                                 Washington.
----------------------------------------------------------------------------------------------------------------
                                               Suborder Pinnipedia
----------------------------------------------------------------------------------------------------------------
Family Otariidae (sea lions
 and fur seals):
    California sea lion.......  U.S. Stock......           3,624               0          25,243               0
    Steller sea lion..........  Eastern U.S.....             108               0             743               0
    Guadalupe fur seal *......  Mexico..........             608               0           4,247               0
    Northern fur seal.........  Eastern Pacific.           2,134               0          14,911               0
                                California......              43               0             300               0
Family Phocidae (true seals):
    Harbor seal...............  Southeast                      0               0               0               0
                                 Alaska--Clarenc
                                 e Strait.
                                Oregon/                        0               0               0               0
                                 Washington
                                 Coastal.
                                Washington                   669               5           3,938              35
                                 Northern Inland
                                 Waters.
                                Hood Canal......           2,686               1          18,662               5
                                Southern Puget             1,090               1           6,657               6
                                 Sound.
    Northern elephant seal....  California......           1,909               1          13,324               1
----------------------------------------------------------------------------------------------------------------
* ESA-listed species (all stocks) within the NWTT Study Area. [dagger] Only designated populations are ESA-
  listed.
\1\ The seven-year totals may be less than the annual totals times seven, given that not all activities occur
  every year, some activities occur multiple times within a year, and some activities only occur a few times
  over the course of a seven-year period.
\2\ The proposed rule incorrectly indicated 32 takes by Level B harassment of the CA/OR/WA stock of humpback
  whale, and 478 takes by Level B harassment of the Eastern North Pacific Offshore stock of killer whale over
  the seven-year period of the rule. Given that the annual take estimate is calculated based on the maximum
  amount of activity that could occur within a one-year period, the seven-year take estimate would, at most, be
  seven times the annual take estimate. (However, we note that in some cases, the seven-year take estimate is
  less than seven times the annual take estimate, as some activities have restrictions on the number of
  activities over the seven-year period.)
\3\ For Kogia Spp., the proposed rule indicated 381 annual takes by Level B harassment, and 2,664 takes by Level
  B harassment over the seven-year period of the rule. These updated take estimates reflect clarifications due
  to rounding errors in the proposed rule.


[[Page 72394]]


  Table 33--Annual and Seven-Year Total Species-Specific Take Estimates Authorized From Acoustic and Explosive
                     Sound Source Effects for All Testing Activities in the NWTT Study Area
----------------------------------------------------------------------------------------------------------------
                                                              Annual                       7-Year total
            Species                   Stock      ---------------------------------------------------------------
                                                      Level B         Level A         Level B         Level A
----------------------------------------------------------------------------------------------------------------
                                Order Cetacea Suborder Mysticeti (baleen whales)
----------------------------------------------------------------------------------------------------------------
Family Balaenopteridae
 (rorquals):
    Blue whale *..............  Eastern North                  8               0              38               0
                                 Pacific.
    Fin whale *...............  Northeast                      2               0              10               0
                                 Pacific.
                                California,                   81               0         \1\ 389               0
                                 Oregon,
                                 Washington.
    Sei whale *...............  Eastern North                 53               0         \1\ 257               0
                                 Pacific.
    Minke whale...............  Alaska..........               2               0               9               0
                                California,                  192               0         \1\ 913               0
                                 Oregon,
                                 Washington.
    Humpback whale *..........  Central North                110               0         \1\ 577               0
                                 Pacific.
                                California,                   89               0         \1\ 456               0
                                 Oregon,
                                 Washington.
Family Eschrichtiidae (gray
 whale):
    Gray whale................  Eastern North                 41               0         \1\ 181               0
                                 Pacific.
----------------------------------------------------------------------------------------------------------------
                                Western North                  0               0               0               0
                                 Pacific[dagger].
----------------------------------------------------------------------------------------------------------------
                                      Suborder Odontoceti (toothed whales)
----------------------------------------------------------------------------------------------------------------
Family Delphinidae (dolphins):
    Bottlenose dolphin........  California,                    3               0              14               0
                                 Oregon,
                                 Washington,
                                 Offshore.
    Killer whale..............  Alaska Resident.              34               0             202               0
                                Eastern North                 89               0             412               0
                                 Pacific
                                 Offshore.
                                Northern                       0               0               0               0
                                 Resident.
                                West Coast                   154               0             831               0
                                 Transient.
                                Southern                      48               0             228               0
                                 Resident
                                 [dagger].
    Northern right whale        California,               13,759               1      \1\ 66,456               7
     dolphin.                    Oregon,
                                 Washington.
    Pacific white-sided         North Pacific...             101               0             603               0
     dolphin.
                                California,               15,681               1      \1\ 76,978            \1\7
                                 Oregon,
                                 Washington.
    Risso's dolphin...........  California,                4,069               0      \1\ 19,636               0
                                 Oregon,
                                 Washington.
    Short-beaked common         California,                  984               0           3,442               0
     dolphin.                    Oregon,
                                 Washington.
    Short-finned pilot whale..  California,                   31               0             126               0
                                 Oregon,
                                 Washington.
    Striped dolphin...........  California,                  344               0           1,294               0
                                 Oregon,
                                 Washington.
Family Kogiidae (Kogia spp.):
    Kogia whales..............  California,              \2\ 500           \2\ 2       1 2 2,375               9
                                 Oregon,
                                 Washington.
Family Phocoenidae
 (porpoises):
    Dall's porpoise...........  Alaska..........             638               0           3,711               0
                                California,               20,398              90      \1\ 98,241         \1\ 456
                                 Oregon,
                                 Washington.
    Harbor porpoise...........  Southeast Alaska             130               0             794               0
                                Northern Oregon/          52,113             103     \1\ 264,999         \1\ 359
                                 Washington
                                 Coast.
                                Northern                   2,018              86      \1\ 11,525         \1\ 261
                                 California/
                                 Southern Oregon.
                                Washington                17,228             137         115,770             930
                                 Inland Waters.
Family Physeteridae (sperm
 whale):
    Sperm whale *.............  California,                  327               0           1,443               0
                                 Oregon,
                                 Washington.
Family Ziphiidae (beaked
 whales):
    Baird's beaked whale......  California,                  420               0           1,738               0
                                 Oregon,
                                 Washington.
    Cuvier's beaked whale.....  California,                1,077               0           4,979               0
                                 Oregon,
                                 Washington.
    Mesoplodon spp............  California,                  470               0           2,172               0
                                 Oregon,
                                 Washington.
----------------------------------------------------------------------------------------------------------------
                                               Suborder Pinnipedia
----------------------------------------------------------------------------------------------------------------
Family Otariidae (sea lions
 and fur seals):
    California sea lion.......  U.S. Stock......          20,474               1      \1\ 93,901           \1\ 4
    Steller sea lion..........  Eastern U.S.....           2,130               0      \1\ 10,744               0
    Guadalupe fur seal *......  Mexico..........             887               0           4,022               0
    Northern fur seal.........  Eastern Pacific.           9,458               0          45,813               0
                                California......             189               0             920               0
Family Phocidae (true seals):
    Harbor seal...............  Southeast                  2,352               0          13,384               0
                                 Alaska--Clarenc
                                 e Strait.
                                Oregon/                    1,180               2       \1\ 6,182           \1\ 6
                                 Washington
                                 Coastal.
                                Washington                   578               0           3,227               0
                                 Northern Inland
                                 Waters.
                                Hood Canal......          58,784               0         396,883               0
                                Southern Puget             5,748               3          39,511          \1\ 21
                                 Sound.
    Northern elephant seal....  California......           2,935               3      \1\ 14,110          \1\ 17
----------------------------------------------------------------------------------------------------------------
* ESA-listed species (all stocks) within the NWTT Study Area. [dagger] Only designated populations are ESA-
  listed.
\1\ The take estimate for these species decreased since the proposed rule, as the Navy has adjusted their
  planned activity by reducing the number of times Mine Countermeasure and Neutralization testing could occur
  over the seven-year period of the rule.
\2\ For Kogia Spp., the proposed rule indicated 501 annual takes by Level B harassment, 1 annual take by Level A
  harassment, and 2,376 takes by Level B harassment over the seven-year period of the rule. These updated take
  estimates reflect clarifications due to rounding errors in the proposed rule.

Estimated Take From Vessel Strikes by Serious Injury or Mortality

    Vessel strikes from commercial, recreational, and military vessels 
are known to affect large whales and have resulted in serious injury 
and occasional fatalities to cetaceans (Berman-Kowalewski et al., 2010; 
Calambokidis, 2012; Douglas et al., 2008; Laggner 2009; Lammers et al., 
2003). Records of collisions date back to the early 17th century, and 
the worldwide number of collisions appears to have increased steadily 
during recent decades (Laist et al., 2001; Ritter 2012).
    Numerous studies of interactions between surface vessels and marine

[[Page 72395]]

mammals have demonstrated that free-ranging marine mammals often, but 
not always (e.g., McKenna et al., 2015), engage in avoidance behavior 
when surface vessels move toward them. It is not clear whether these 
responses are caused by the physical presence of a surface vessel, the 
underwater noise generated by the vessel, or an interaction between the 
two (Amaral and Carlson, 2005; Au and Green, 2000; Bain et al., 2006; 
Bauer 1986; Bejder et al., 1999; Bejder and Lusseau, 2008; Bejder et 
al., 2009; Bryant et al., 1984; Corkeron, 1995; Erbe, 2002; 
F[eacute]lix, 2001; Goodwin and Cotton, 2004; Greig et al., 2020; 
Guilpin et al., 2020; Keen et al., 2019; Lemon et al., 2006; Lusseau, 
2003; Lusseau, 2006; Magalhaes et al., 2002; Nowacek et al., 2001; 
Redfern et al., 2020; Richter et al., 2003; Scheidat et al., 2004; 
Simmonds, 2005; Szesciorka et al., 2019; Watkins, 1986; Williams et 
al., 2002; Wursig et al., 1998). Several authors suggest that the noise 
generated during motion is probably an important factor (Blane and 
Jaakson, 1994; Evans et al., 1992; Evans et al., 1994). Water 
disturbance may also be a factor. These studies suggest that the 
behavioral responses of marine mammals to surface vessels are similar 
to their behavioral responses to predators. Avoidance behavior is 
expected to be even stronger in the subset of instances during which 
the Navy is conducting training or testing activities using active 
sonar or explosives.
    The marine mammals most vulnerable to vessel strikes are those that 
spend extended periods of time at the surface in order to restore 
oxygen levels within their tissues after deep dives (e.g., sperm 
whales). In addition, some baleen whales seem generally unresponsive to 
vessel sound, making them more susceptible to vessel collisions 
(Nowacek et al., 2004). These species are primarily large, slow moving 
whales.
    Some researchers have suggested the relative risk of a vessel 
strike can be assessed as a function of animal density and the 
magnitude of vessel traffic (e.g., Fonnesbeck et al., 2008; Vanderlaan 
et al., 2008). Differences among vessel types also influence the 
probability of a vessel strike. The ability of any ship to detect a 
marine mammal and avoid a collision depends on a variety of factors, 
including environmental conditions, ship design, size, speed, and 
ability and number of personnel observing, as well as the behavior of 
the animal. Vessel speed, size, and mass are all important factors in 
determining if injury or death of a marine mammal is likely due to a 
vessel strike. For large vessels, speed and angle of approach can 
influence the severity of a strike. For example, Vanderlaan and Taggart 
(2007) found that between vessel speeds of 8.6 and 15 knots, the 
probability that a vessel strike is lethal increases from 0.21 to 0.79. 
Large whales also do not have to be at the water's surface to be 
struck. Silber et al. (2010) found when a whale is below the surface 
(about one to two times the vessel draft), under certain circumstances 
(vessel speed and location of the whale relative to the ship's 
centerline), there is likely to be a pronounced propeller suction 
effect. This suction effect may draw the whale into the hull of the 
ship, increasing the probability of propeller strikes.
    There are some key differences between the operation of military 
and non-military vessels, which make the likelihood of a military 
vessel striking a whale lower than some other vessels (e.g., commercial 
merchant vessels). Key differences include:
     Many military ships have their bridges positioned closer 
to the bow, offering better visibility ahead of the ship (compared to a 
commercial merchant vessel);
     There are often aircraft associated with the training or 
testing activity (which can serve as Lookouts), which can more readily 
detect cetaceans in the vicinity of a vessel or ahead of a vessel's 
present course before crew on the vessel would be able to detect them;
     Military ships are generally more maneuverable than 
commercial merchant vessels, and if cetaceans are spotted in the path 
of the ship, could be capable of changing course more quickly;
     The crew size on military vessels is generally larger than 
merchant ships, allowing for stationing more trained Lookouts on the 
bridge. At all times when Navy vessels are underway, trained Lookouts 
and bridge navigation teams are used to detect objects on the surface 
of the water ahead of the ship, including cetaceans. Additional 
personnel, beyond those already stationed on the bridge and on 
navigation teams, are positioned as Lookouts during some training 
events; and
     When submerged, submarines are generally slow moving (to 
avoid detection) and therefore marine mammals at depth with a submarine 
are likely able to avoid collision with the submarine. When a submarine 
is transiting on the surface, there are Lookouts serving the same 
function as they do on surface ships.
    Vessel strike to marine mammals is not associated with any specific 
training or testing activity but is rather an extremely limited and 
sporadic, but possible, accidental result of Navy vessel movement 
within the NWTT Study Area or while in transit.
    Data from the ports of Vancouver, British Columbia; Seattle, 
Washington; and Tacoma, Washington indicate there were more than 7,000 
commercial vessel transits in 2017 associated with visits to just those 
ports (The Northwest Seaport Alliance, 2018; Vancouver Fraser Port 
Authority). This number of vessel transits does not account for other 
vessel traffic in the Strait of Juan de Fuca or Puget Sound including 
commercial ferries, tourist vessels, or recreational vessels. 
Additional commercial traffic in the NWTT Study Area also includes 
vessels transiting offshore along the Pacific coast, bypassing ports in 
Canada and Washington; traffic associated with ports to the south along 
the coast of Washington and in Oregon; and vessel traffic in Southeast 
Alaska (Nuka Research & Planning Group, 2012). Navy vessel traffic 
accounts for only a small portion of vessel activities in the NWTT 
Study Area. The Navy has, in total, the following homeported 
operational vessels: 2 aircraft carriers, 6 destroyers, 14 submarines, 
and 22 smaller security vessels with a combined annual total of 241 
Navy vessel transits (see Appendix A (Navy Activities Descriptions) of 
the 2020 FSEIS/OEIS for descriptions of the number of vessels used 
during the various types of Navy's planned activities). Activities 
involving military vessel movement would be widely dispersed throughout 
the NWTT Study Area.
    Navy vessel strike records have been kept since 1995, and since 
1995 there have been two recorded strikes of whales by Navy vessels (or 
vessels being operated on behalf of the Navy) in the NWTT Study Area. 
Neither strike was associated with training or testing activities. The 
first strike occurred in 2012 by a Navy destroyer off the southern 
coast of Oregon while in transit to San Diego. The whale was suspected 
to be a minke whale due to the appearance and size (25 ft, dark with 
white belly), however the Navy could not rule out the possibility that 
it was a juvenile fin whale. The whale was observed swimming after the 
strike and no blood or injury was sighted. The second strike occurred 
in 2016 by a U.S. Coast Guard cutter operating on behalf of the Navy as 
part of a Maritime Security Operation escort vessel in the Strait of 
Juan de Fuca. The whale was positively identified as a humpback whale. 
It was observed for 10 minutes post-collision and appeared normal at 
the surface. There was no blood

[[Page 72396]]

observed in the water and the whale subsequently swam away.
    In order to account for the potential risk from vessel movement 
within the NWTT Study Area within the seven-year period in particular, 
the Navy requested incidental takes based on probabilities derived from 
a Poisson distribution using ship strike data between 2009-2018 in the 
NWTT Study Area (the time period from when current mitigation measures 
to reduce the likelihood of vessel strikes were instituted until the 
Navy conducted the analysis for the Navy's application), as well as 
historical at-sea days in the NWTT Study Area from 2009-2018 and 
estimated potential at-sea days for the period from 2020 to 2027 
covered by the requested regulations. This distribution predicted the 
probabilities of a specific number of strikes (n=0, 1, 2, etc.) over 
the period from 2020 to 2027. The analysis for the period of 2020 to 
2027 is described in detail in Chapter 6.6 (Vessel Strike Analysis) of 
the Navy's rulemaking/LOA application.
    For the same reasons listed above, describing why a Navy vessel 
strike is comparatively unlikely, it is highly unlikely that a Navy 
vessel would strike a whale, dolphin, porpoise, or pinniped without 
detecting it and, accordingly, NMFS is confident that the Navy's 
reported strikes are accurate and appropriate for use in the analysis. 
Specifically, Navy ships have multiple Lookouts, including on the 
forward part of the ship that can visually detect a hit animal, in the 
unlikely event ship personnel do not feel the strike. Unlike the 
situation for non-Navy ships engaged in commercial activities, NMFS and 
the Navy have no evidence that the Navy has struck a whale and not 
detected it. Navy's strict internal procedures and mitigation 
requirements include reporting of any vessel strikes of marine mammals, 
and the Navy's discipline, extensive training (not only for detecting 
marine mammals, but for detecting and reporting any potential 
navigational obstruction), and strict chain of command give NMFS a high 
level of confidence that all strikes actually get reported.
    The Navy used those two whale strikes in their calculations to 
determine the number of strikes likely to result from their activities 
and evaluated data beginning in 2009. The Navy's Marine Species 
Awareness Training was first used in 2006 and was fully integrated 
across the Navy in 2009, which is why the Navy uses 2009 as the date to 
begin the analysis. The adoption of additional mitigation measures to 
address ship strike also began in 2009, and will remain in place along 
with additional mitigation measures during the seven years of this 
rule. The probability analysis concluded that there was a 26 percent 
chance that zero whales would be struck by Navy vessels over the seven-
year period, and a 35, 24, 11, and 4 percent chance that one, two, 
three, or four whales, respectively, would be struck over the seven-
year period (with a 74 percent chance total that at least one whale 
would be struck over the seven-year period). Therefore, the Navy 
estimates, and NMFS agrees, that there is some probability (an 11 
percent chance) that the Navy could strike, and take by serious injury 
or mortality, up to three large whales incidental to training and 
testing activities within the NWTT Study Area over the course of the 
seven years.
    Small whales, delphinids, porpoises, and pinnipeds are not expected 
to be struck by Navy vessels. In addition to the reasons listed above 
that make it unlikely that the Navy will hit a large whale (more 
maneuverable ships, larger crews, etc.), the following are the 
additional reasons that vessel strike of dolphins, small whales, 
porpoises, and pinnipeds is considered very unlikely. Dating back more 
than 20 years and for as long as it has kept records, the Navy has no 
records of individuals of these groups (including Southern Resident 
killer whales) being struck by a vessel as a result of Navy activities 
and, further, their smaller size and maneuverability make a strike 
unlikely. Also, NMFS has never received any reports from other 
authorized activities indicating that these species have been struck by 
vessels. Worldwide ship strike records show little evidence of strikes 
of these groups from the shipping sector and larger vessels, and the 
majority of the Navy's activities involving faster-moving vessels (that 
could be considered more likely to hit a marine mammal) are located in 
offshore areas where smaller delphinid, porpoise, and pinniped 
densities are lower. Since 2005, though, three vessel strikes of 
Southern Resident killer whales have been recorded: one collision with 
a commercial whale watch vessel in 2005 (the whale recovered), one 
collision with a tug boat in 2006 (the whale was killed), and one 
animal found dead in 2016 with evidence of blunt force trauma 
consistent with a vessel strike. However, given the information above 
regarding the overall low likelihood of vessel strikes of small whales, 
delphinids, porpoises, and pinnipeds by Navy vessels, as well as the 
enhanced mitigation for, and high visibility of, Southern Resident 
killer whales, Southern Resident killer whales are not expected to be 
struck by Navy vessels. Based on this information and the Navy's 
assessment, NMFS concludes that there is the potential for incidental 
take by vessel strike of large whales only (i.e., no dolphins, small 
whales, porpoises, or pinnipeds) over the course of the seven-year 
regulations from training and testing activities.
    Taking into account the available information regarding how many of 
any given stock could be struck and therefore should be authorized for 
take, NMFS considered three factors in addition to those considered in 
the Navy's request: (1)The relative likelihood of hitting one stock 
versus another based on available strike data from all vessel types as 
denoted in the SARs, (2) whether the Navy has ever definitively struck 
an individual from a particular species or stock in the NWTT Study 
Area, and if so, how many times, and (3) whether there are records that 
an individual from a particular species or stock has been struck by any 
vessel in the NWTT Study Area, and if so, how many times (based on ship 
strike records provided by the NMFS West Coast Region in February 
2020). To address number (1) above, NMFS compiled information from 
NMFS' SARs on detected annual rates of large whale serious injury or 
mortality (M/SI) from vessel collisions (Table 34). The annual rates of 
large whale serious injury or mortality from vessel collisions from the 
SARs help inform the relative susceptibility of large whale species to 
vessel strike in NWTT Study Area as recorded systematically over the 
last five years (the period used for the SARs). However, we note that 
the SARs present strike data from the stock's entire range, which is 
much larger than the NWTT Study Area, and available ship strike records 
show that the majority of strikes that occur off the U.S. West Coast 
occur in southern California. We summed the annual rates of serious 
injury or mortality from vessel collisions as reported in the SARs, 
then divided each species' annual rate by this sum to get the 
proportion of strikes for each species/stock. To inform the likelihood 
of striking a particular species of large whale, we multiplied the 
proportion of striking each species by the probability of striking at 
least one whale (i.e., 74 percent, as described by the Navy's 
probability analysis above). We note that these probabilities vary from 
year to year as the average annual mortality for a given five-year 
window in the SAR changes; however, over the years and through changing 
SARs, stocks tend to consistently maintain a relatively higher or 
relatively lower

[[Page 72397]]

likelihood of being struck (and we include the annual averages from 
2017 SARs in Table 34 to illustrate).
    The probabilities calculated as described above are then considered 
in combination with the information indicating the species that the 
Navy has definitively hit in the NWTT Study Area since 1995 (since they 
started tracking consistently) and the species that are known to have 
been struck by any vessel (through regional stranding data) in the NWTT 
Study Area. We also note that Rockwood et al. (2017) modeled the likely 
vessel strike of blue whales, fin whales, and humpback whales on the 
U.S. West Coast (discussed in more detail in the Serious Injury or 
Mortality subsection of the Analysis and Negligible Impact 
Determination section), and those numbers help inform the relative 
likelihood that the Navy will hit those stocks.
    For each indicated stock, Table 34 includes the percent likelihood 
of hitting an individual whale once based on SAR data, total strikes 
from Navy vessels (from 1995), total strikes from any vessel (from 2000 
from regional stranding data), and modeled vessel strikes from Rockwood 
et al. (2017). The last column indicates the annual serious injury or 
mortality authorized.

                                  Table 34--Summary of Factors Considered in Determining the Number of Individuals in Each Stock Potentially Struck by a Vessel
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                      Percent
                                                                                          Annual rate  Annual rate   likelihood  Total known
                                                                                            of M/SI      of M/SI     of hitting   strikes in  Total known  Rockwood et      MMPA
                                                                                          from vessel  from vessel   individual    OR, WA,        navy      al. (2017)   authorized     Annual
              ESA status                        Species                   Stock            collision    collision       from     northern CA   strikes in    modeled    takes (from   authorized
                                                                                           (observed    (observed     species/    (from 2000   NWTT study     vessel       the 3         take
                                                                                           from 2017    from 2019    stock once  to present)      area     strikes \5\     total)
                                                                                             SARs)        SARs)      (from 2019      \1\
                                                                                                                     SARs data)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Listed...............................  Blue whale..............  Eastern North Pacific..            0          0.4          3.7  ...........  ...........           18            0            0
                                       Fin whale...............  Northeast Pacific......          0.2          0.4          3.7       \2\ 10  ...........  ...........            2         0.29
                                                                 CA/OR/WA...............          1.8          1.6         14.8       \2\ 10  ...........           43            2         0.29
                                       Sei whale...............  Eastern North Pacific..            0          0.2         1.85  ...........  ...........  ...........            0            0
                                       Humpback whale..........  CA/OR/WA (Mexico and             1.1          2.1       19.425        \3\ 4        \4\ 1           22            2         0.29
                                                                  Central America DPS).
                                       Sperm whale.............  CA/OR/WA...............          0.2            0            0            3  ...........  ...........            1         0.14
Not Listed...........................  Minke whale.............  Alaska.................            0            0            0  ...........  ...........  ...........            0            0
                                                                 CA/OR/WA...............            0            0            0            1            1  ...........            1         0.14
                                       Gray whale..............  Eastern North Pacific..            2          0.8          7.4            9  ...........  ...........            1         0.14
                                       Humpback whale..........  Central North Pacific            2.6          2.5       23.125        \3\ 4        \4\ 1  ...........            2         0.29
                                                                  (Hawaii DPS).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: A ``-'' indicates that the field does not apply.
\1\ Only one ship strike was reported in California in the NWTT Study Area (which is limited to Humboldt and Del Norte Counties). This strike occurred in 2004 in Humboldt County and was not
  identified to species.
\2\ A total of 10 fin whale strikes are reported in the regional stranding database, however no information on stock is provided. As these two stocks of fin whales are known to overlap
  spatially and temporally in the NWTT Study Area, the 10 reported strikes could come from either stock or a combination of both stocks.
\3\ A total of 4 humpback whales strikes are reported in the regional stranding database, however no information on stock is provided. As these two stocks of humpback whales are known to
  overlap spatially and temporally in the NWTT Study Area, the 4 reported strikes could come from either stock or a combination of both stocks.
\4\ One humpback whale was reported as struck by a U.S. Coast Guard cutter operating on behalf of the Navy, however it was not possible for the Navy to determine which stock this whale came
  from. As these two stocks of humpback whales are known to overlap spatially and temporally in the NWTT Study Area, this whale could have come from either stock.
\5\ Rockwood et al. modeled likely annual vessel strikes off the U.S. West Coast for these three species only.

    Accordingly, stocks that have no record of having been struck by 
any vessel are considered unlikely to be struck by the Navy in the 
seven-year period of the rule. Stocks that have never been struck by 
the Navy, have rarely been struck by other vessels, and have a low 
likelihood of being struck based on the SAR calculation and a low 
relative abundance (Eastern North Pacific stock of blue whales, Eastern 
North Pacific stock of sei whales, and Alaska stock of minke whales) 
are also considered unlikely to be struck by the Navy during the seven-
year rule. This rules out all but seven stocks.
    The two stocks of humpback whales (California/Oregon/Washington 
(CA/OR/WA) and Central North Pacific) and two stocks of fin whales (CA/
OR/WA and Northeast Pacific) are known to overlap spatially and 
temporally in the NWTT Study Area, and it is not possible to 
distinguish the difference between individuals of these stocks based on 
visual sightings in the field. The Navy has previously struck a 
humpback whale in the NWTT Study Area, and it is the second most common 
species struck by any vessel in the Study Area based on stranding data. 
Based on the SAR data, the two stocks of humpback whales also have the 
highest likelihood of being struck. Though the Navy has not 
definitively struck a fin whale in the NWTT Study Area (noting that the 
Navy could not rule out that the minke whale strike could have been a 
juvenile fin whale), fin whales are the most common species struck by 
any vessel in the Study Area based on stranding data. Based on the SAR 
data, the CA/OR/WA stock has the third highest likelihood of being 
struck. Based on all of these factors, it is considered reasonable that 
humpback whales (from either the CA/OR/WA or Central North Pacific 
stocks) could be struck twice and fin whales (from either the CA/OR/WA 
or Northeast Pacific stocks) could be struck twice during the seven-
year rule.
    Based on the SAR data, the CA/OR/WA stock of sperm whales and CA/
OR/WA stock of minke whales have a very low likelihood of being struck. 
However, 3 sperm whales have been struck by non-Navy vessels in the 
NWTT Study Area (in 2002, 2007, and 2012) and the Navy has previously 
struck a minke whale in the NWTT Study Area. Therefore, we consider it 
reasonable that an individual from each of these stocks could be struck 
by the Navy once during the seven-year rule. Finally, based on 
stranding data, gray whales are the second most commonly struck whale 
in the NWTT Study Area and the SAR data indicates that on average, 0.8 
whales from this stock are struck throughout the stock's range each 
year. Based on these data, we consider it reasonable that an individual 
from the Eastern North Pacific stock of gray whales could be struck by 
the Navy once during the seven-year rule.
    In conclusion, although it is generally unlikely that any whales 
will be struck in a year, based on the information and analysis above, 
NMFS anticipates that no more than three whales have the potential to 
be taken by serious injury or mortality over the seven-year period of 
the rule. Of those three whales over the seven years, no more than two 
may come from any of the following species/stocks: Fin whale (which may 
come from either the Northeast Pacific or CA/OR/WA stock) and humpback 
whale (which may come from either the Central North Pacific or CA/OR/WA 
stock). Additionally, of those three whales over the seven years no 
more than one may come from any of the

[[Page 72398]]

following species/stocks: Sperm whale (CA/OR/WA stock), minke whale 
(CA/OR/WA stock), and gray whale (Eastern North Pacific stock). 
Accordingly, NMFS has evaluated under the negligible impact standard 
the mortality or serious injury (M/SI) of 0.14 or 0.29 whales annually 
from each of these stocks (i.e., 1 or 2 takes, respectively, divided by 
seven years to get the annual number), along with the expected 
incidental takes by harassment. We do not anticipate, nor have we 
authorized, ship strike takes to blue whales (Eastern North Pacific 
stock), minke whales (Alaska stock), or sei whales (Eastern North 
Pacific stock).

Mitigation Measures

    Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the 
permissible methods of taking pursuant to the activity, and other means 
of effecting the least practicable adverse impact on the species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance, and on the 
availability of the species or stocks for subsistence uses (``least 
practicable adverse impact''). NMFS does not have a regulatory 
definition for least practicable adverse impact. The 2004 NDAA amended 
the MMPA as it relates to military readiness activities and the 
incidental take authorization process such that a determination of 
``least practicable adverse impact'' on the species or stock shall 
include consideration of personnel safety, practicality of 
implementation, and impact on the effectiveness of the military 
readiness activity.
    In Conservation Council for Hawaii v. National Marine Fisheries 
Service, 97 F. Supp. 3d 1210, 1229 (D. Haw. 2015), the Court stated 
that NMFS ``appear[s] to think [it] satisf[ies] the statutory `least 
practicable adverse impact' requirement with a `negligible impact' 
finding.'' Expressing similar concerns in a challenge to a U.S. Navy 
Surveillance Towed Array Sensor System Low Frequency Active Sonar 
(SURTASS LFA) incidental take rule (77 FR 50290), the Ninth Circuit 
Court of Appeals in Natural Resources Defense Council (NRDC) v. 
Pritzker, 828 F.3d 1125, 1134 (9th Cir. 2016), stated, ``[c]ompliance 
with the `negligible impact' requirement does not mean there [is] 
compliance with the `least practicable adverse impact' standard.'' As 
the Ninth Circuit noted in its opinion, however, the Court was 
interpreting the statute without the benefit of NMFS' formal 
interpretation. We state here explicitly that NMFS is in full agreement 
that the ``negligible impact'' and ``least practicable adverse impact'' 
requirements are distinct, even though both statutory standards refer 
to species and stocks. With that in mind, we provide further 
explanation of our interpretation of least practicable adverse impact, 
and explain what distinguishes it from the negligible impact standard. 
This discussion is consistent with previous rules we have issued, such 
as the Navy's Hawaii-Southern California Training and Testing (HSTT) 
rule (85 FR 41780; July 10, 2020), Atlantic Fleet Training and Testing 
(AFTT) rule (84 FR 70712; December 23, 2019), and Mariana Islands 
Training and Testing (MITT) rule (85 FR 46302; July 31, 2020).
    Before NMFS can issue incidental take regulations under section 
101(a)(5)(A) of the MMPA, it must make a finding that the total taking 
will have a ``negligible impact'' on the affected ``species or stocks'' 
of marine mammals. NMFS' and U.S. Fish and Wildlife Service's 
implementing regulations for section 101(a)(5) both define ``negligible 
impact'' as an impact resulting from the specified activity that cannot 
be reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival (50 CFR 216.103 and 50 CFR 18.27(c)). 
Recruitment (i.e., reproduction) and survival rates are used to 
determine population growth rates \4\ and, therefore are considered in 
evaluating population level impacts.
---------------------------------------------------------------------------

    \4\ A growth rate can be positive, negative, or flat.
---------------------------------------------------------------------------

    As stated in the preamble to the proposed rule for the MMPA 
incidental take implementing regulations, not every population-level 
impact violates the negligible impact requirement. The negligible 
impact standard does not require a finding that the anticipated take 
will have ``no effect'' on population numbers or growth rates: The 
statutory standard does not require that the same recovery rate be 
maintained, rather that no significant effect on annual rates of 
recruitment or survival occurs. The key factor is the significance of 
the level of impact on rates of recruitment or survival. (54 FR 40338, 
40341-42; September 29, 1989).
    While some level of impact on population numbers or growth rates of 
a species or stock may occur and still satisfy the negligible impact 
requirement--even without consideration of mitigation--the least 
practicable adverse impact provision separately requires NMFS to 
prescribe means of effecting the least practicable adverse impact on 
the species or stocks and their habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, 50 CFR 
216.102(b), which are typically identified as mitigation measures.\5\
---------------------------------------------------------------------------

    \5\ Separately, NMFS also must prescribe means of effecting the 
least practicable adverse impact on the availability of the species 
or stocks for subsistence uses, when applicable. See the Subsistence 
Harvest of Marine Mammals section for separate discussion of the 
effects of the specified activities on Alaska Native subsistence 
use.
---------------------------------------------------------------------------

    The negligible impact and least practicable adverse impact 
standards in the MMPA both call for evaluation at the level of the 
``species or stock.'' The MMPA does not define the term ``species.'' 
However, Merriam-Webster Dictionary defines ``species'' to include 
``related organisms or populations potentially capable of 
interbreeding.'' See www.merriam-webster.com/dictionary/species 
(emphasis added). Section 3(11) of the MMPA defines ``stock'' as a 
group of marine mammals of the same species or smaller taxa in a common 
spatial arrangement that interbreed when mature. The definition of 
``population'' is a group of interbreeding organisms that represents 
the level of organization at which speciation begins. www.merriam-webster.com/dictionary/population. The definition of ``population'' is 
strikingly similar to the MMPA's definition of ``stock,'' with both 
involving groups of individuals that belong to the same species and 
located in a manner that allows for interbreeding. In fact under MMPA 
section 3(11), the term ``stock'' in the MMPA is interchangeable with 
the statutory term ``population stock.'' Both the negligible impact 
standard and the least practicable adverse impact standard call for 
evaluation at the level of the species or stock, and the terms 
``species'' and ``stock'' both relate to populations; therefore, it is 
appropriate to view both the negligible impact standard and the least 
practicable adverse impact standard as having a population-level focus.
    This interpretation is consistent with Congress' statutory findings 
for enacting the MMPA, nearly all of which are most applicable at the 
species or stock (i.e., population) level. See MMPA section 2 (finding 
that it is species and population stocks that are or may be in danger 
of extinction or depletion; that it is species and population stocks 
that should not diminish beyond being significant functioning elements 
of their ecosystems; and that it is species and population stocks that 
should not be permitted to diminish below their optimum sustainable 
population level). Annual rates of recruitment (i.e., reproduction) and 
survival are the key biological metrics used in the evaluation of 
population-level impacts, and

[[Page 72399]]

accordingly these same metrics are also used in the evaluation of 
population level impacts for the least practicable adverse impact 
standard.
    Recognizing this common focus of the least practicable adverse 
impact and negligible impact provisions on the ``species or stock'' 
does not mean we conflate the two standards; despite some common 
statutory language, we recognize the two provisions are different and 
have different functions. First, a negligible impact finding is 
required before NMFS can issue an incidental take authorization. 
Although it is acceptable to use the mitigation measures to reach a 
negligible impact finding (see 50 CFR 216.104(c)), no amount of 
mitigation can enable NMFS to issue an incidental take authorization 
for an activity that still would not meet the negligible impact 
standard. Moreover, even where NMFS can reach a negligible impact 
finding--which we emphasize does allow for the possibility of some 
``negligible'' population-level impact--the agency must still prescribe 
measures that will effect the least practicable amount of adverse 
impact upon the affected species or stocks.
    Section 101(a)(5)(A)(i)(II) requires NMFS to issue, in conjunction 
with its authorization, binding--and enforceable--restrictions (in the 
form of regulations) setting forth how the activity must be conducted, 
thus ensuring the activity has the ``least practicable adverse impact'' 
on the affected species or stocks. In situations where mitigation is 
specifically needed to reach a negligible impact determination, section 
101(a)(5)(A)(i)(II) also provides a mechanism for ensuring compliance 
with the ``negligible impact'' requirement. Finally, the least 
practicable adverse impact standard also requires consideration of 
measures for marine mammal habitat, with particular attention to 
rookeries, mating grounds, and other areas of similar significance, and 
for subsistence impacts, whereas the negligible impact standard is 
concerned solely with conclusions about the impact of an activity on 
annual rates of recruitment and survival.\6\ In NRDC v. Pritzker, the 
Court stated, ``[t]he statute is properly read to mean that even if 
population levels are not threatened significantly, still the agency 
must adopt mitigation measures aimed at protecting marine mammals to 
the greatest extent practicable in light of military readiness needs.'' 
Pritzker at 1134 (emphases added). This statement is consistent with 
our understanding stated above that even when the effects of an action 
satisfy the negligible impact standard (i.e., in the Court's words, 
``population levels are not threatened significantly''), still the 
agency must prescribe mitigation under the least practicable adverse 
impact standard. However, as the statute indicates, the focus of both 
standards is ultimately the impact on the affected ``species or 
stock,'' and not solely focused on or directed at the impact on 
individual marine mammals.
---------------------------------------------------------------------------

    \6\ Outside of the military readiness context, mitigation may 
also be appropriate to ensure compliance with the ``small numbers'' 
language in MMPA sections 101(a)(5)(A) and (D).
---------------------------------------------------------------------------

    We have carefully reviewed and considered the Ninth Circuit's 
opinion in NRDC v. Pritzker in its entirety. While the Court's 
reference to ``marine mammals'' rather than ``marine mammal species or 
stocks'' in the italicized language above might be construed as holding 
that the least practicable adverse impact standard applies at the 
individual ``marine mammal'' level, i.e., that NMFS must require 
mitigation to minimize impacts to each individual marine mammal unless 
impracticable, we believe such an interpretation reflects an incomplete 
appreciation of the Court's holding. In our view, the opinion as a 
whole turned on the Court's determination that NMFS had not given 
separate and independent meaning to the least practicable adverse 
impact standard apart from the negligible impact standard, and further, 
that the Court's use of the term ``marine mammals'' was not addressing 
the question of whether the standard applies to individual animals as 
opposed to the species or stock as a whole. We recognize that while 
consideration of mitigation can play a role in a negligible impact 
determination, consideration of mitigation measures extends beyond that 
analysis. In evaluating what mitigation measures are appropriate, NMFS 
considers the potential impacts of the specified activities, the 
availability of measures to minimize those potential impacts, and the 
practicability of implementing those measures, as we describe below.

Implementation of Least Practicable Adverse Impact Standard

    Given the NRDC v. Pritzker decision, we discuss here how we 
determine whether a measure or set of measures meets the ``least 
practicable adverse impact'' standard. Our separate analysis of whether 
the take anticipated to result from Navy's activities meets the 
``negligible impact'' standard appears in the Analysis and Negligible 
Impact Determination section below.
    Our evaluation of potential mitigation measures includes 
consideration of two primary factors:
    (1) The manner in which, and the degree to which, implementation of 
the potential measure(s) is expected to reduce adverse impacts to 
marine mammal species or stocks, their habitat, and their availability 
for subsistence uses (where relevant \7\). This analysis considers such 
things as the nature of the potential adverse impact (such as 
likelihood, scope, and range), the likelihood that the measure will be 
effective if implemented, and the likelihood of successful 
implementation; and
---------------------------------------------------------------------------

    \7\ For more information on measures to effect the least 
practicable adverse impact on the availability of species or stocks 
for subsistence uses, see the Subsistence Harvest of Marine Mammals 
section below.
---------------------------------------------------------------------------

    (2) The practicability of the measures for applicant 
implementation. Practicability of implementation may consider such 
things as cost, impact on the specified activities, and, in the case of 
a military readiness activity, specifically considers personnel safety, 
practicality of implementation, and impact on the effectiveness of the 
military readiness activity (when evaluating measures to reduce adverse 
impact on the species or stocks).
Evaluation of Measures for Least Practicable Adverse Impact on Species 
or Stocks
    While the language of the least practicable adverse impact standard 
calls for minimizing impacts to affected species or stocks, we 
recognize that the reduction of impacts to those species or stocks 
accrues through the application of mitigation measures that limit 
impacts to individual animals. Accordingly, NMFS' analysis focuses on 
measures that are designed to avoid or minimize impacts on individual 
marine mammals that are likely to increase the probability or severity 
of population-level effects.
    While direct evidence of impacts to species or stocks from a 
specified activity is rarely available, and additional study is still 
needed to understand how specific disturbance events affect the fitness 
of individuals of certain species, there have been improvements in 
understanding the process by which disturbance effects are translated 
to the population. With recent scientific advancements (both marine 
mammal energetic research and the development of energetic frameworks), 
the relative likelihood or degree of impacts on species or stocks may 
often be inferred given a detailed understanding of the activity, the

[[Page 72400]]

environment, and the affected species or stocks--and the best available 
science has been used here. This same information is used in the 
development of mitigation measures and helps us understand how 
mitigation measures contribute to lessening effects (or the risk 
thereof) to species or stocks. We also acknowledge that there is always 
the potential that new information, or a new recommendation could 
become available in the future and necessitate reevaluation of 
mitigation measures (which may be addressed through adaptive 
management) to see if further reductions of population impacts are 
possible and practicable.
    In the evaluation of specific measures, the details of the 
specified activity will necessarily inform each of the two primary 
factors discussed above (expected reduction of impacts and 
practicability), and are carefully considered to determine the types of 
mitigation that are appropriate under the least practicable adverse 
impact standard. Analysis of how a potential mitigation measure may 
reduce adverse impacts on a marine mammal stock or species, 
consideration of personnel safety, practicality of implementation, and 
consideration of the impact on effectiveness of military readiness 
activities are not issues that can be meaningfully evaluated through a 
yes/no lens. The manner in which, and the degree to which, 
implementation of a measure is expected to reduce impacts, as well as 
its practicability in terms of these considerations, can vary widely. 
For example, a time/area restriction could be of very high value for 
decreasing population-level impacts (e.g., avoiding disturbance of 
feeding females in an area of established biological importance) or it 
could be of lower value (e.g., decreased disturbance in an area of high 
productivity but of less biological importance). Regarding 
practicability, a measure might involve restrictions in an area or time 
that impede the Navy's ability to certify a strike group (higher impact 
on mission effectiveness and national security), or it could mean 
delaying a small in-port training event by 30 minutes to avoid exposure 
of a marine mammal to injurious levels of sound (lower impact). A 
responsible evaluation of ``least practicable adverse impact'' will 
consider the factors along these realistic scales. Accordingly, the 
greater the likelihood that a measure will contribute to reducing the 
probability or severity of adverse impacts to the species or stock or 
its habitat, the greater the weight that measure is given when 
considered in combination with practicability to determine the 
appropriateness of the mitigation measure, and vice versa. We discuss 
consideration of these factors in greater detail below.
    1. Reduction of adverse impacts to marine mammal species or stocks 
and their habitat. The emphasis given to a measure's ability to reduce 
the impacts on a species or stock considers the degree, likelihood, and 
context of the anticipated reduction of impacts to individuals (and how 
many individuals) as well as the status of the species or stock.
    The ultimate impact on any individual from a disturbance event 
(which informs the likelihood of adverse species- or stock-level 
effects) is dependent on the circumstances and associated contextual 
factors, such as duration of exposure to stressors. Though any proposed 
mitigation needs to be evaluated in the context of the specific 
activity and the species or stocks affected, measures with the 
following types of effects have greater value in reducing the 
likelihood or severity of adverse species- or stock-level impacts: 
Avoiding or minimizing injury or mortality; limiting interruption of 
known feeding, breeding, mother/young, or resting behaviors; minimizing 
the abandonment of important habitat (temporally and spatially); 
minimizing the number of individuals subjected to these types of 
disruptions; and limiting degradation of habitat. Mitigating these 
types of effects is intended to reduce the likelihood that the activity 
will result in energetic or other types of impacts that are more likely 
to result in reduced reproductive success or survivorship. It is also 
important to consider the degree of impacts that are expected in the 
absence of mitigation in order to assess the added value of any 
potential measures. Finally, because the least practicable adverse 
impact standard gives NMFS discretion to weigh a variety of factors 
when determining appropriate mitigation measures and because the focus 
of the standard is on reducing impacts at the species or stock level, 
the least practicable adverse impact standard does not compel 
mitigation for every kind of take, or every individual taken, if that 
mitigation is unlikely to meaningfully contribute to the reduction of 
adverse impacts on the species or stock and its habitat, even when 
practicable for implementation by the applicant.
    The status of the species or stock is also relevant in evaluating 
the appropriateness of potential mitigation measures in the context of 
least practicable adverse impact. The following are examples of factors 
that may (either alone, or in combination) result in greater emphasis 
on the importance of a mitigation measure in reducing impacts on a 
species or stock: The stock is known to be decreasing or status is 
unknown, but believed to be declining; the known annual mortality (from 
any source) is approaching or exceeding the potential biological 
removal (PBR) level (as defined in MMPA section 3(20)); the affected 
species or stock is a small, resident population; or the stock is 
involved in a UME or has other known vulnerabilities, such as 
recovering from an oil spill.
    Habitat mitigation, particularly as it relates to rookeries, mating 
grounds, and areas of similar significance, is also relevant to 
achieving the standard and can include measures such as reducing 
impacts of the activity on known prey utilized in the activity area or 
reducing impacts on physical habitat. As with species- or stock-related 
mitigation, the emphasis given to a measure's ability to reduce impacts 
on a species or stock's habitat considers the degree, likelihood, and 
context of the anticipated reduction of impacts to habitat. Because 
habitat value is informed by marine mammal presence and use, in some 
cases there may be overlap in measures for the species or stock and for 
use of habitat.
    We consider available information indicating the likelihood of any 
measure to accomplish its objective. If evidence shows that a measure 
has not typically been effective or successful, then either that 
measure should be modified or the potential value of the measure to 
reduce effects should be lowered.
    2. Practicability. Factors considered may include cost, impact on 
activities, and, in the case of a military readiness activity, will 
include personnel safety, practicality of implementation, and impact on 
the effectiveness of the military readiness activity (see MMPA section 
101(a)(5)(A)(ii)).

Assessment of Mitigation Measures for NWTT Study Area

    Section 216.104(a)(11) of NMFS' implementing regulations requires 
an applicant for incidental take authorization to include in its 
request, among other things, ``the availability and feasibility 
(economic and technological) of equipment, methods, and manner of 
conducting such activity or other means of effecting the least 
practicable adverse impact upon the affected species or stocks, their 
habitat, and [where applicable] on their availability for subsistence 
uses, paying particular attention to rookeries, mating grounds, and 
areas of similar significance.'' Thus NMFS' analysis of

[[Page 72401]]

the sufficiency and appropriateness of an applicant's measures under 
the least practicable adverse impact standard will always begin with 
evaluation of the mitigation measures presented in the application.
    NMFS has fully reviewed the specified activities together with the 
mitigation measures included in the Navy's rulemaking/LOA application 
and the 2020 NWTT FSEIS/OEIS to determine if the mitigation measures 
would result in the least practicable adverse impact on marine mammals 
and their habitat. NMFS worked with the Navy in the development of the 
Navy's initially proposed measures, which are informed by years of 
implementation and monitoring. A complete discussion of the Navy's 
evaluation process used to develop, assess, and select mitigation 
measures, which was informed by input from NMFS, can be found in 
Section 5 (Mitigation) and Appendix K (Geographic Mitigation 
Assessment) of the 2020 NWTT FSEIS/OEIS. The process described in 
Chapter 5 (Mitigation) and Appendix K (Geographic Mitigation 
Assessment) of the 2020 NWTT FSEIS/OEIS robustly supported NMFS' 
independent evaluation of whether the mitigation measures meet the 
least practicable adverse impact standard.
    As a general matter, where an applicant proposes measures that are 
likely to reduce impacts to marine mammals, the fact that they are 
included in the application indicates that the measures are 
practicable, and it is not necessary for NMFS to conduct a detailed 
analysis of the measures the applicant proposed (rather, they are 
simply included). However, it is still necessary for NMFS to consider 
whether there are additional practicable measures that would 
meaningfully reduce the probability or severity of impacts that could 
affect reproductive success or survivorship.
    Since publication of the proposed rule, and in consideration of 
public comments received, additional mitigation requirements have been 
added that will further reduce the likelihood and/or severity of 
adverse impacts on marine mammal species and their habitat and are 
practicable for implementation. Below we describe the added measures 
that the Navy will implement and explain the manner in which they are 
expected to reduce the likelihood or severity of adverse impacts on 
marine mammals and their habitats.
    1. The Navy will only conduct explosive Mine Countermeasure and 
Neutralization testing in daylight hours and in Beaufort Sea state 
number 3 conditions or less. This will assist Navy Lookouts in 
effectively sighting potential marine mammals, including Southern 
Resident killer whales, in the procedural mitigation zones.
    2. The Navy will implement a new mitigation area, the Juan de Fuca 
Eddy Marine Species Mitigation Area, in which the Navy will not conduct 
explosive Mine Countermeasure and Neutralization Testing activities and 
will limit surface ship hull-mounted MF1 mid-frequency active sonar, 
eliminating impacts to marine mammals in this area from Mine 
Countermeasure and Neutralization activities, and minimizing impacts to 
marine mammals from MF1 sonar in this area. Specifically, the Navy will 
conduct no more than a total of 33 hours of surface ship hull-mounted 
MF1 mid-frequency active sonar during testing annually within 20 nmi 
from shore in the Marine Species Coastal Mitigation Area, in this new 
Juan de Fuca Eddy Marine Species Mitigation Area, and in the Olympic 
Coast National Marine Sanctuary Mitigation Area combined.
    3. The Navy will issue seasonal awareness notification messages 
within 50 nmi from shore to alert Navy ships and aircraft operating 
within the Marine Species Coastal Mitigation Area to the possible 
presence of increased concentrations of Southern Resident killer whales 
from December 1 to June 30, humpback whales from May 1 through December 
31, and gray whales from May 1 to November 30. To assist in avoiding 
interactions with whales, the Navy will instruct vessels to remain 
vigilant to the presence of Southern Resident killer whales, humpback 
whales, and gray whales that may be vulnerable to vessel strikes or 
potential impacts from training and testing activities. Platforms will 
use the information from the awareness notification messages to assist 
their visual observation of applicable mitigation zones during training 
and testing activities and to aid in the implementation of procedural 
mitigation.
    4. The Navy will implement seasonal restrictions and distance-from-
shore requirements for certain explosive bins, as described in detail 
in the Mitigation Areas section of this final rule. Additionally, the 
Navy will implement new annual and seven-year explosive ordnance 
limitations specific to explosive mine countermeasure and 
neutralization testing. These restrictions and limitations will further 
reduce impacts to marine mammals from explosives in nearshore and 
offshore habitats, including important feeding and migration areas for 
Southern Resident killer whales and humpback whales.
    5. As noted above in #2, the Navy will conduct no more than a total 
of 33 hours of surface ship hull-mounted MF1 mid-frequency active sonar 
during testing annually within 20 nmi from shore in the Marine Species 
Coastal Mitigation Area, in the new Juan de Fuca Eddy Marine Species 
Mitigation Area, and in the Olympic Coast National Marine Sanctuary 
Mitigation Area combined. The annual restriction for testing previously 
only applied to the Olympic Coast National Marine Sanctuary Mitigation 
Area. This final rule also removes an exception that excluded the 
Quinault Range Site from the annual sonar restrictions that was 
included in the proposed rule. Now, the annual restrictions will apply 
throughout the entire Olympic Coastal National Marine Sanctuary 
Mitigation Area, including within the portion of the mitigation area 
that overlaps the Quinault Range Site. This reduction in activities is 
in areas that are important for Southern Resident killer whale and 
humpback whale feeding and migration.
    6. The Navy will conduct a maximum of one Unmanned Underwater 
Vehicle Training event within 12 nmi from shore at the Quinault Range 
Site, and will cancel or move Unmanned Underwater Vehicle Training 
events within 12 nmi from shore at the Quinault Range Site if Southern 
Resident killer whales are detected at the planned training location 
during the event planning process, or immediately prior to the event, 
as applicable. This measure is expected to help avoid any potential 
impacts on Southern Resident killer whales during Unmanned Underwater 
Vehicle Training events.
    7. NMFS has included several new measures in the Puget Sound and 
Strait of Juan de Fuca Mitigation Area that the Navy had been 
voluntarily implementing previously during Phase II activities, but are 
now required mitigation measures. Specifically, the Navy will not use 
low-, mid-, or high-frequency active sonar during training or testing 
unless a required element (i.e., a criterion necessary for the success 
of the event) necessitates the activity be conducted in NWTT Inland 
Waters during (1) Unmanned Underwater Vehicle Training, (2) Civilian 
Port Defense--Homeland Security Anti-Terrorism/Force Protection 
Exercises, (3) activities conducted by Naval Sea Systems Command at 
designated locations, or (4) pierside sonar maintenance or testing at 
designated locations. Additionally, the Navy will use the lowest active 
sonar source levels practical to successfully accomplish

[[Page 72402]]

each event, and will not use explosives during testing. The Navy will 
not use explosives during training except at the Hood Canal Explosive 
Ordnance Disposal (EOD) Range and Crescent Harbor EOD Range during 
explosive mine neutralization activities involving the use of Navy 
divers. Additionally, Navy event planners are required to coordinate 
with Navy biologists during the event planning process prior to these 
events. The Navy will not conduct non-explosive live fire events 
(except firing blank weapons), including gunnery exercises, missile 
exercises, torpedo exercises, bombing exercises, and Kinetic Energy 
Weapon Testing.
    8. In addition to the previous voluntary measures that the Navy 
will now implement as mitigation measures, the Navy will also implement 
several new mitigation measures within the Puget Sound and Strait of 
Juan de Fuca Mitigation Area. Within the Puget Sound and Strait of Juan 
de Fuca Mitigation Area, the Navy will conduct a maximum of one 
Unmanned Underwater Vehicle Training activity annually at the Navy 3 
Operating Area, Navy 7 Operating Area, and Manchester Fuel Depot (i.e., 
a maximum of one event at each location). Additionally, Navy event 
planners are required to coordinate with Navy biologists during the 
event planning process prior to conducting Unmanned Underwater Vehicle 
Training at the Navy 3 Operating Area, Manchester Fuel Depot, Crescent 
Harbor Explosive Ordnance Disposal Range, and Navy 7 Operating Area, 
and to cancel or move events to another training location if the 
presence of Southern Resident killer whales is reported through 
available monitoring networks. Additionally, the Navy will issue annual 
seasonal awareness notification messages to alert Navy ships and 
aircraft operating within the Puget Sound and Strait of Juan de Fuca 
Mitigation Area to the possible presence of concentrations of Southern 
Resident killer whales and gray whales. These messages are expected to 
help further avoid potential impacts from training and testing 
activities on Southern Resident killer whales and gray whales, and will 
coincide with the seasons in which Southern Resident killer whales and 
gray whales are most likely to be observed in the mitigation area (July 
1 to November 30 for Southern Resident killer whales, and March 1 to 
May 31 for gray whales).
    As described in the Mitigation Areas section of this final rule, 
the Puget Sound and Strait of Juan de Fuca Mitigation Area encompasses 
the full extent of NWTT Inland Waters, and includes feeding and 
potential migration habitat for gray whales and critical habitat for 
Southern Resident killer whales and one of their primary sources of 
prey, Puget Sound Chinook salmon. New mitigation in the Puget Sound and 
Strait of Juan de Fuca Mitigation Area is designed to help avoid any 
potential impacts from training and testing on Southern Resident killer 
whales in NWTT Inland Waters. As stated in the Mitigation Areas section 
of this final rule, with implementation of these new mitigation 
measures, we do not anticipate any take of Southern Resident killer 
whales in NWTT Inland Waters due to NWTT training and testing 
activities. Additionally, we expect that the new mitigation in this 
mitigation area will help reduce potential impacts on gray whales from 
testing and training activities.
    In addition, the Navy has agreed to procedural mitigation measures 
that will reduce the probability and/or severity of impacts expected to 
result from acute exposure to acoustic sources and explosives, such as 
hearing impairment, more severe behavioral disturbance, as well as the 
probability of vessel strike. Specifically, the Navy will use a 
combination of delayed starts, powerdowns, and shutdowns to avoid or 
minimize mortality or serious injury, minimize the likelihood or 
severity of PTS or other injury, and reduce instances of TTS or more 
severe behavioral disturbance caused by acoustic sources or explosives. 
The Navy will also implement multiple time/area restrictions that will 
reduce take of marine mammals (as well as impacts on marine mammal 
habitat) in areas where or at times when they are known to engage in 
important behaviors, such as feeding, where the disruption of those 
behaviors would have a higher probability of resulting in impacts on 
reproduction or survival of individuals that could lead to population-
level impacts.
    The Navy assessed the practicability of these measures in the 
context of personnel safety, practicality of implementation, and their 
impacts on the Navy's ability to meet their Title 10 requirements and 
found that the measures are supportable. NMFS has independently 
evaluated the measures the Navy proposed in the manner described 
earlier in this section (i.e., in consideration of their ability to 
reduce adverse impacts on marine mammal species and their habitat and 
their practicability for implementation). We have determined that the 
measures will significantly and adequately reduce impacts on the 
affected marine mammal species and stocks and their habitat and, 
further, be practicable for Navy implementation. Therefore, the 
mitigation measures assure that the Navy's activities will have the 
least practicable adverse impact on the species or stocks and their 
habitat.

Measures Evaluated but not Included

    The Navy also evaluated numerous measures in the 2020 NWTT FSEIS/
OEIS that were not included in the Navy's rulemaking/LOA application, 
and NMFS independently reviewed and concurs with the Navy's analysis 
that their inclusion was not appropriate under the least practicable 
adverse impact standard based on our assessment. The Navy considered 
these additional potential mitigation measures in two groups. First, 
Section 5 (Mitigation) of the 2020 NWTT FSEIS/OEIS, in the Measures 
Considered but Eliminated section, includes an analysis of an array of 
different types of mitigation that have been recommended over the years 
by non-governmental organizations or the public, through scoping or 
public comment on environmental compliance documents. Appendix K 
(Geographic Mitigation Assessment) of the 2020 NWTT FSEIS/OEIS includes 
an in-depth analysis of time/area restrictions that have been 
recommended over time. As described in Chapter 5 (Mitigation) of the 
2020 NWTT FSEIS/OEIS, commenters sometimes recommend that the Navy 
reduce its overall amount of training, reduce explosive use, modify its 
sound sources, completely replace live training and testing with 
computer simulation, or include time of day restrictions. Many of these 
mitigation measures could potentially reduce the number of marine 
mammals taken, via direct reduction of the activities or amount of 
sound energy put in the water. However, as described in Section 5 
(Mitigation) of the 2020 NWTT FSEIS/OEIS, the Navy needs to train and 
test in the conditions in which it fights--and these types of 
modifications fundamentally change the activity in a manner that will 
not support the purpose and need for the training and testing (i.e., 
are entirely impracticable) and therefore are not considered further. 
NMFS finds the Navy's explanation for why adoption of these 
recommendations would unacceptably undermine the purpose of the testing 
and training persuasive. After independent review, NMFS finds Navy's 
judgment on the impacts of potential mitigation measures to personnel 
safety, practicality of implementation, and the effectiveness of 
training and testing within the NWTT Study Area persuasive, and for 
these

[[Page 72403]]

reasons, NMFS finds that these measures do not meet the least 
practicable adverse impact standard because they are not practicable.
    Second, in Chapter 5 (Mitigation) of the 2020 NWTT FSEIS/OEIS, the 
Navy evaluated additional potential procedural mitigation measures, 
including increased mitigation zones, ramp-up measures, additional 
passive acoustic and visual monitoring, and decreased vessel speeds. 
Some of these measures have the potential to incrementally reduce take 
to some degree in certain circumstances, though the degree to which 
this would occur is typically low or uncertain. However, as described 
in the Navy's analysis, the measures would have significant direct 
negative effects on mission effectiveness and are considered 
impracticable (see Section 5 Mitigation of 2020 NWTT FSEIS/OEIS). NMFS 
independently reviewed the Navy's evaluation and concurs with this 
assessment, which supports NMFS' findings that the impracticability of 
this additional mitigation would greatly outweigh any potential minor 
reduction in marine mammal impacts that might result; therefore, these 
additional mitigation measures are not warranted.
    Last, Appendix K (Geographic Mitigation Assessment) of the 2020 
NWTT FSEIS/OEIS describes a comprehensive method for analyzing 
potential geographic mitigation that includes consideration of both a 
biological assessment of how the potential time/area limitation would 
benefit the species and its habitat (e.g., is a key area of biological 
importance or would result in avoidance or reduction of impacts) in the 
context of the stressors of concern in the specific area and an 
operational assessment of the practicability of implementation 
(including an assessment of the specific importance of that area for 
training, considering proximity to training ranges and emergency 
landing fields and other issues). For most of the areas that were 
considered in the 2020 NWTT FSEIS/OEIS but not included in this rule, 
the Navy found that the mitigation was not warranted because the 
anticipated reduction of adverse impacts on marine mammal species and 
their habitat was not sufficient to offset the impracticability of 
implementation. In some cases potential benefits to marine mammals were 
non-existent, while in others the consequences on mission effectiveness 
were too great.
    NMFS has reviewed the Navy's analysis in Section 5 Mitigation and 
Appendix K Geographic Mitigation Assessment of the 2020 NWTT FSEIS/
OEIS, which considers the same factors that NMFS considers to satisfy 
the least practicable adverse impact standard, and concurs with the 
analysis and conclusions. Therefore, NMFS is not including any of the 
measures that the Navy ruled out in the 2020 NWTT FSEIS/OEIS.
    Below, we describe additional measures that were considered but 
eliminated during the development of the final rule: (1) A full 
restriction on Mine Countermeasure and Neutralization testing in water 
depths less than 650 ft. and (2) A full restriction on Undersea Warfare 
Testing within 20 nmi from shore in the Marine Species Coastal 
Mitigation Area (except within the portion of the mitigation area that 
overlaps the Quinault Range Site).
    Regarding the consideration of a full restriction on Mine 
Countermeasure and Neutralization testing in water depths less than 650 
ft, water depths drop rapidly from 650 ft to 1,000 ft in the NWTT 
Offshore Area, and the Navy plans to conduct this activity in areas 
where water depths are less than 1,000 ft. Limiting the available 
testing area to areas deeper than 650 ft would allow the Navy a span of 
only one to two nmi in some cases to conduct the activity. Given the 
limited available area beyond 650 ft, and given that the typical 
testing depth of Mine Countermeasure and Neutralization testing is 300 
ft, limiting testing to water depths greater than 650 ft would not be 
practical to implement with respect to allowing the Navy to meet 
mission requirements. In consideration of the reductions in potential 
impacts provided by the restrictions on Mine Countermeasure and 
Neutralization testing in the geographic mitigation areas, the required 
procedural mitigation restricting Mine Countermeasure and 
Neutralization testing to daylight hours only and in a Beaufort sea 
state of 3 or less, and combined with the impracticability for the 
Navy, NMFS found that this measure was not warranted.
    Regarding the consideration of a full restriction on Undersea 
Warfare Testing within 20 nmi from shore in the Marine Species Coastal 
Mitigation Area (except within the portion of the mitigation area that 
overlaps with the Quinault Range Site), this final rule instead 
includes a cap of 33 hours of surface ship hull-mounted MF1 mid-
frequency active sonar during testing annually within 20 nmi from shore 
in the Marine Species Coastal Mitigation Area, in the Juan de Fuca Eddy 
Marine Species Mitigation Area, and in the Olympic Coast National 
Marine Sanctuary Mitigation Area combined. NMFS concurred with the 
Navy's analysis that it would be impracticable to fully restrict 
Undersea Warfare testing in this area, and this limitation is expected 
to minimize impacts from sonar in the three areas combined.
    The following sections describe the mitigation measures that will 
be implemented in association with the training and testing activities 
analyzed in this document. These are the mitigation measures that NMFS 
has determined will ensure the least practicable adverse impact on all 
affected species and their habitat, including the specific 
considerations for military readiness activities. The mitigation 
measures are organized into two categories: procedural mitigation and 
mitigation areas.

Procedural Mitigation

    Procedural mitigation is mitigation that the Navy will implement 
whenever and wherever an applicable training or testing activity takes 
place within the NWTT Study Area. Procedural mitigation is customized 
for each applicable activity category or stressor. Procedural 
mitigation generally involves: (1) The use of one or more trained 
Lookouts to diligently observe for specific biological resources 
(including marine mammals) within a mitigation zone, (2) requirements 
for Lookouts to immediately communicate sightings of these specific 
biological resources to the appropriate watch station for information 
dissemination, and (3) requirements for the watch station to implement 
mitigation (e.g., halt an activity) until certain recommencement 
conditions have been met. The first procedural mitigation (Table 35) is 
designed to aid Lookouts and other applicable Navy personnel in their 
observation, environmental compliance, and reporting responsibilities. 
The remainder of the procedural mitigation measures (Tables 36 through 
49) are organized by stressor type and activity category and include 
acoustic stressors (i.e., active sonar, weapons firing noise), 
explosive stressors (i.e., sonobuoys, torpedoes, medium-caliber and 
large-caliber projectiles, missiles, bombs, mine counter-measure and 
neutralization activities, mine neutralization involving Navy divers), 
and physical disturbance and strike stressors (i.e., vessel movement, 
towed in-water devices, small-, medium-, and large-caliber non-
explosive practice munitions, non-explosive missiles, non-explosive 
bombs and mine shapes).

[[Page 72404]]



     Table 35--Procedural Mitigation for Environmental Awareness and
                                Education
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     All training and testing activities, as applicable.
Mitigation Requirements:
     Appropriate Navy personnel (including civilian personnel)
     involved in mitigation and training or testing activity reporting
     under the specified activities will complete one or more modules of
     the U.S. Navy Afloat Environmental Compliance Training Series, as
     identified in their career path training plan. Modules include:
        --Introduction to the U.S. Navy Afloat Environmental Compliance
         Training Series. The introductory module provides information
         on environmental laws (e.g., Endangered Species Act, Marine
         Mammal Protection Act) and the corresponding responsibilities
         that are relevant to Navy training and testing activities. The
         material explains why environmental compliance is important in
         supporting the Navy's commitment to environmental stewardship.
        --Marine Species Awareness Training. All bridge watch personnel,
         Commanding Officers, Executive Officers, maritime patrol
         aircraft aircrews, anti[hyphen]submarine warfare and mine
         warfare rotary-wing aircrews, Lookouts, and equivalent civilian
         personnel must successfully complete the Marine Species
         Awareness Training prior to standing watch or serving as a
         Lookout. The Marine Species Awareness Training provides
         information on sighting cues, visual observation tools and
         techniques, and sighting notification procedures. Navy
         biologists developed Marine Species Awareness Training to
         improve the effectiveness of visual observations for biological
         resources, focusing on marine mammals and sea turtles, and
         including floating vegetation, jellyfish aggregations, and
         flocks of seabirds.
        --U.S. Navy Protective Measures Assessment Protocol. This module
         provides the necessary instruction for accessing mitigation
         requirements during the event planning phase using the
         Protective Measures Assessment Protocol software tool.
        --U.S. Navy Sonar Positional Reporting System and Marine Mammal
         Incident Reporting. This module provides instruction on the
         procedures and activity reporting requirements for the Sonar
         Positional Reporting System and marine mammal incident
         reporting.
------------------------------------------------------------------------


            Table 36--Procedural Mitigation for Active Sonar
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
 
     Low-frequency active sonar, mid-frequency active sonar,
     high-frequency active sonar
        --For vessel-based active sonar activities, mitigation applies
         only to sources that are positively controlled and deployed
         from manned surface vessels (e.g., sonar sources towed from
         manned surface platforms).
        --For aircraft-based active sonar activities, mitigation applies
         only to sources that are positively controlled and deployed
         from manned aircraft that do not operate at high altitudes
         (e.g., rotary-wing aircraft). Mitigation does not apply to
         active sonar sources deployed from unmanned aircraft or
         aircraft operating at high altitudes (e.g., maritime patrol
         aircraft).
Number of Lookouts and Observation Platform:
     Hull-mounted sources:
        --1 Lookout: Platforms with space or manning restrictions while
         underway (at the forward part of a small boat or ship) and
         platforms using active sonar while moored or at anchor
         (including pierside).
        --2 Lookouts: Platforms without space or manning restrictions
         while underway (at the forward part of the ship).
    Sources that are not hull-mounted:
        --1 Lookout on the ship or aircraft conducting the activity.
Mitigation Requirements:
     Mitigation zones:
        --1,000 yd power down, 500 yd power down, and 200 yd or 100 yd
         shut down for low-frequency active sonar at 200 decibels (dB)
         and hull-mounted mid-frequency active sonar (see During the
         activity below).
        --200 yd or 100 yd shut down for low-frequency active sonar <200
         dB, mid-frequency active sonar sources that are not hull-
         mounted, and high-frequency active sonar (see During the
         activity below).
     Prior to the initial start of the activity (e.g., when
     maneuvering on station):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of active sonar transmission.
     During the activity:
        --Low-frequency active sonar at 200 decibels (dB) and hull-
         mounted mid-frequency active sonar: (1) Navy personnel must
         observe the mitigation zone for marine mammals; Navy personnel
         will power down active sonar transmission by 6 dB if a marine
         mammal is observed within 1,000 yd of the sonar source; Navy
         personnel will power down an additional 4 dB (10 dB total) if a
         marine mammal is observed within 500 yd of the sonar source;
         Navy personnel must cease transmission if cetaceans are
         observed within 200 yd of the sonar source in any location in
         the Study Area; (2) Navy personnel must cease transmission if
         pinnipeds in the NWTT Offshore Area or Western Behm Canal are
         observed within 200 yd of the sonar source and cease
         transmission if pinnipeds in NWTT Inland Waters are observed
         within 100 yd of the sonar source (except if hauled out on, or
         in the water near, man-made structures and vessels).
        --Low-frequency active sonar <200 dB, mid-frequency active sonar
         sources that are not hull-mounted, and high-frequency active
         sonar: Navy personnel must observe the mitigation zone for
         marine mammals; Navy personnel will cease transmission if
         cetaceans are observed within 200 yd of the sonar source in any
         location in the Study Area. Navy personnel will cease
         transmission if pinnipeds in the NWTT Offshore Area or Western
         Behm Canal are observed within 200 yd of the sonar source; Navy
         personnel will cease transmission if pinnipeds in NWTT Inland
         Waters is observed within 100 yd of the sonar source (except if
         hauled out on, or in the water near, man-made structures and
         vessels).
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:

[[Page 72405]]

 
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         or powering up active sonar transmission) until one of the
         following conditions has been met: (1) The animal is observed
         exiting the mitigation zone; (2) the animal is thought to have
         exited the mitigation zone based on a determination of its
         course, speed, and movement relative to the sonar source; (3)
         the mitigation zone has been clear from any additional
         sightings for 10 minutes for aircraft-deployed sonar sources or
         30 minutes for vessel-deployed sonar sources; (4) for mobile
         activities, the active sonar source has transited a distance
         equal to double that of the mitigation zone size beyond the
         location of the last sighting; or (5) for activities using hull-
         mounted sonar, the Lookout concludes that dolphins are
         deliberately closing in on the ship to ride the ship's bow
         wave, and are therefore out of the main transmission axis of
         the sonar (and there are no other marine mammal sightings
         within the mitigation zone).
------------------------------------------------------------------------


        Table 37--Procedural Mitigation for Weapons Firing Noise
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Weapons firing noise associated with large-caliber gunnery
     activities.
Number of Lookouts and Observation Platform:
     1 Lookout positioned on the ship conducting the firing.
        --Depending on the activity, the Lookout could be the same one
         described for Procedural Mitigation for Explosive Medium-
         Caliber and Large-Caliber Projectiles (Table 40) or Procedural
         Mitigation for Small-, Medium-, and Large-Caliber Non-Explosive
         Practice Munitions (Table 47).
Mitigation Requirements:
     Mitigation zone:
        --30[deg] on either side of the firing line out to 70 yd from
         the muzzle of the weapon being fired.
     Prior to the initial start of the activity:
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of weapons firing.
     During the activity:
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease weapons firing.
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         weapons firing) until one of the following conditions has been
         met: (1) The animal is observed exiting the mitigation zone;
         (2) the animal is thought to have exited the mitigation zone
         based on a determination of its course, speed, and movement
         relative to the firing ship; (3) the mitigation zone has been
         clear from any additional sightings for 30 minutes; or (4) for
         mobile activities, the firing ship has transited a distance
         equal to double that of the mitigation zone size beyond the
         location of the last sighting.
------------------------------------------------------------------------


         Table 38--Procedural Mitigation for Explosive Sonobuoys
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Explosive sonobuoys.
Number of Lookouts and Observation Platform:
     1 Lookout positioned in an aircraft or on a small boat.
     If additional platforms are participating in the activity,
     personnel positioned in those assets (e.g., safety observers,
     evaluators) will support observing the mitigation zone for marine
     mammals while performing their regular duties.
Mitigation Requirements:
     Mitigation zone:
        --600 yd. around an explosive sonobuoy.
     Prior to the initial start of the activity (e.g., during
     deployment of a sonobuoy field, which typically lasts 20-30
     minutes):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will conduct passive acoustic monitoring for
         marine mammals; personnel will use information from detections
         to assist visual observations.
        --Navy personnel will visually observe the mitigation zone for
         marine mammals; if marine mammals are observed, Navy personnel
         will relocate or delay the start of sonobuoy or source/receiver
         pair detonations.
     During the activity:
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease sonobuoy or source/receiver pair detonations.
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         detonations) until one of the following conditions has been
         met: (1) The animal is observed exiting the mitigation zone;
         (2) the animal is thought to have exited the mitigation zone
         based on a determination of its course, speed, and movement
         relative to the sonobuoy; or (3) the mitigation zone has been
         clear from any additional sightings for 10 min when the
         activity involves aircraft that have fuel constraints, or 30
         min when the activity involves aircraft that are not typically
         fuel constrained.

[[Page 72406]]

 
     After completion of the activity (e.g., prior to
     maneuvering off station):
        --When practical (e.g., when platforms are not constrained by
         fuel restrictions or mission-essential follow-on commitments),
         Navy personnel will observe the vicinity of where detonations
         occurred; if any injured or dead marine mammals are observed,
         Navy personnel will follow established incident reporting
         procedures.
        --If additional platforms are supporting this activity (e.g.,
         providing range clearance), Navy personnel positioned on these
         assets will assist in the visual observation of the area where
         detonations occurred.
------------------------------------------------------------------------


         Table 39--Procedural Mitigation for Explosive Torpedoes
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Explosive torpedoes.
Number of Lookouts and Observation Platform:
     1 Lookout positioned in an aircraft.
     If additional platforms are participating in the activity,
     personnel positioned in those assets (e.g., safety observers,
     evaluators) will support observing the mitigation zone for marine
     mammals while performing their regular duties.
Mitigation Requirements:
     Mitigation zone:
        --2,100 yd around the intended impact location.
     Prior to the initial start of the activity (e.g., during
     deployment of the target):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will conduct passive acoustic monitoring for
         marine mammals; personnel will use information from detections
         to assist visual observations.
        --Navy personnel will visually observe the mitigation zone for
         marine mammals; if marine mammals are observed, Navy personnel
         will relocate or delay the start of firing.
     During the activity:
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease firing.
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         firing) until one of the following conditions has been met: (1)
         The animal is observed exiting the mitigation zone; (2) the
         animal is thought to have exited the mitigation zone based on a
         determination of its course, speed, and movement relative to
         the intended impact location; or (3) the mitigation zone has
         been clear from any additional sightings for 10 minutes when
         the activity involves aircraft that have fuel constraints, or
         30 minutes when the activity involves aircraft that are not
         typically fuel constrained.
     After completion of the activity (e.g., prior to
     maneuvering off station):
        --When practical (e.g., when platforms are not constrained by
         fuel restrictions or mission-essential follow-on commitments),
         Navy personnel will observe for marine mammals in the vicinity
         of where detonations occurred; if any injured or dead marine
         mammals are observed, Navy personnel will follow established
         incident reporting procedures.
        --If additional platforms are supporting this activity (e.g.,
         providing range clearance), Navy personnel positioned on these
         assets will assist in the visual observation of the area where
         detonations occurred.
------------------------------------------------------------------------


 Table 40--Procedural Mitigation for Explosive Medium-Caliber and Large-
                           Caliber Projectiles
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Gunnery activities using explosive medium-caliber and large-
     caliber projectiles
 
        --Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform:
         1 Lookout on the vessel conducting the activity.
        --For activities using explosive large-caliber projectiles,
         depending on the activity, the Lookout could be the same as the
         one described for Procedural Mitigation for Weapons Firing
         Noise (Table 37).
     If additional platforms are participating in the activity,
     personnel positioned in those assets (e.g., safety observers,
     evaluators) will support observing the mitigation zone for marine
     mammals while performing their regular duties.
Mitigation Requirements:
 Mitigation zones:
        --600 yd around the intended impact location for explosive
         medium-caliber projectiles.
        --1,000 yd around the intended impact location for explosive
         large-caliber projectiles.
 Prior to the initial start of the activity (e.g., when
 maneuvering on station):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of firing.
     During the activity:
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease firing.

[[Page 72407]]

 
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         firing) until one of the following conditions has been met: (1)
         The animal is observed exiting the mitigation zone; (2) the
         animal is thought to have exited the mitigation zone based on a
         determination of its course, speed, and movement relative to
         the intended impact location; (3) the mitigation zone has been
         clear from any additional sightings for 30 minutes for vessel-
         based firing; or (4) for activities using mobile targets, the
         intended impact location has transited a distance equal to
         double that of the mitigation zone size beyond the location of
         the last sighting.
     After completion of the activity (e.g., prior to
     maneuvering off station):
        --When practical (e.g., when platforms are not constrained by
         fuel restrictions or mission-essential follow-on commitments),
         Navy personnel will observe for marine mammals in the vicinity
         of where detonations occurred; if any injured or dead marine
         mammals are observed, Navy personnel will follow established
         incident reporting procedures.
        --If additional platforms are supporting this activity (e.g.,
         providing range clearance), Navy personnel positioned on these
         assets will assist in the visual observation of the area where
         detonations occurred.
------------------------------------------------------------------------


         Table 41--Procedural Mitigation for Explosive Missiles
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Aircraft-deployed explosive missiles.
        --Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform
     1 Lookout positioned in an aircraft
     If additional platforms are participating in the activity,
     personnel positioned in those assets (e.g., safety observers,
     evaluators) will support observing the mitigation zone for marine
     mammals and other applicable biological resources while performing
     their regular duties.
Mitigation Requirements:
     Mitigation zone:
        --2,000 yd around the intended impact location.
     Prior to the initial start of the activity (e.g., during a
     fly-over of the mitigation zone):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of firing.
     During the activity:
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease firing.
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         firing) until one of the following conditions has been met: (1)
         The animal is observed exiting the mitigation zone; (2) the
         animal is thought to have exited the mitigation zone based on a
         determination of its course, speed, and movement relative to
         the intended impact location; or (3) the mitigation zone has
         been clear from any additional sightings for 10 minutes when
         the activity involves aircraft that have fuel constraints, or
         30 minutes when the activity involves aircraft that are not
         typically fuel constrained.
     After completion of the activity (e.g., prior to
     maneuvering off station):
        --When practical (e.g., when platforms are not constrained by
         fuel restrictions or mission-essential follow-on commitments),
         Navy personnel will observe the vicinity of where detonations
         occurred; if any injured or dead marine mammals are observed,
         Navy personnel will follow established incident reporting
         procedures.
        --If additional platforms are supporting this activity (e.g.,
         providing range clearance), Navy personnel positioned on these
         assets will assist in the visual observation of the area where
         detonations occurred.
------------------------------------------------------------------------


           Table 42--Procedural Mitigation for Explosive Bombs
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Explosive bombs.
Number of Lookouts and Observation Platform:
     1 Lookout positioned in the aircraft conducting the
     activity.
     If additional platforms are participating in the activity,
     personnel positioned in those assets (e.g., safety observers,
     evaluators) will support observing the mitigation zone for marine
     mammals while performing their regular duties.
Mitigation Requirements:
     Mitigation zone:
        --2,500 yd around the intended target.
     Prior to the initial start of the activity (e.g., when
     arriving on station):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of bomb deployment.
     During the activity (e.g., during target approach):

[[Page 72408]]

 
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease bomb deployment.
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         bomb deployment) until one of the following conditions has been
         met: (1) the animal is observed exiting the mitigation zone;
         (2) the animal is thought to have exited the mitigation zone
         based on a determination of its course, speed, and movement
         relative to the intended target; (3) the mitigation zone has
         been clear from any additional sightings for 10 min; or (4) for
         activities using mobile targets, the intended target has
         transited a distance equal to double that of the mitigation
         zone size beyond the location of the last sighting.
     After completion of the activity (e.g., prior to
     maneuvering off station):
        --When practical (e.g., when platforms are not constrained by
         fuel restrictions or mission-essential follow-on commitments),
         Navy personnel will observe for marine mammals in the vicinity
         of where detonations occurred; if any injured or dead marine
         mammals are observed, Navy personnel will follow established
         incident reporting procedures.
        --If additional platforms are supporting this activity (e.g.,
         providing range clearance), Navy personnel positioned on these
         assets will assist in the visual observation of the area where
         detonations occurred.
------------------------------------------------------------------------


  Table 43--Procedural Mitigation for Explosive Mine Countermeasure and
                        Neutralization Activities
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Explosive Mine Countermeasure and Neutralization
     activities.
Number of Lookouts and Observation Platform:
     1 Lookout positioned on a vessel or in an aircraft when
     implementing the smaller mitigation zone.
     2 Lookouts (one positioned in an aircraft and one on a
     small boat) when implementing the larger mitigation zone.
     If additional platforms are participating in the activity,
     Navy personnel positioned in those assets (e.g., safety observers,
     evaluators) will support observing the mitigation zone for marine
     mammals while performing their regular duties.
Mitigation Requirements:
     Mitigation zones:
        --600 yd around the detonation site for activities using <=5 lb
         net explosive weight.
        --2,100 yd around the detonation site for activities using >5-60
         lb net explosive weight.
     Prior to the initial start of the activity (e.g., when
     maneuvering on station; typically, 10 minutes when the activity
     involves aircraft that have fuel constraints, or 30 minutes when
     the activity involves aircraft that are not typically fuel
     constrained):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of detonations.
     During the activity:
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease detonations.
        --Navy personnel will use the smallest practicable charge size
         for each activity.
        --Navy personnel will conduct activities in daylight hours and
         only in Beaufort Sea state number 3 conditions or less.
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         detonations) until one of the following conditions has been
         met: (1) the animal is observed exiting the mitigation zone;
         (2) the animal is thought to have exited the mitigation zone
         based on a determination of its course, speed, and movement
         relative to detonation site; or (3) the mitigation zone has
         been clear from any additional sightings for 10 min when the
         activity involves aircraft that have fuel constraints, or 30
         min when the activity involves aircraft that are not typically
         fuel constrained.
     After completion of the activity (typically 10 min when the
     activity involves aircraft that have fuel constraints, or 30 min
     when the activity involves aircraft that are not typically fuel
     constrained):
        --Navy personnel will observe for marine mammals in the vicinity
         of where detonations occurred; if any injured or dead marine
         mammals are observed, Navy personnel will follow established
         incident reporting procedures.
        --If additional platforms are supporting this activity (e.g.,
         providing range clearance), Navy personnel positioned on these
         assets will assist in the visual observation of the area where
         detonations occurred.
------------------------------------------------------------------------


    Table 44--Procedural Mitigation for Explosive Mine Neutralization
                    Activities lnvolving Navy Divers
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Explosive mine neutralization activities involving Navy
     divers.
Number of Lookouts and Observation Platform:
     2 Lookouts on two small boats with one Lookout each, one of
     which will be a Navy biologist.
     All divers placing the charges on mines will support the
     Lookouts while performing their regular duties and will report
     applicable sightings to the lead Lookout, the supporting small
     boat, or the Range Safety Officer.
     If additional platforms are participating in the activity,
     personnel positioned on those assets (e.g., safety observers,
     evaluators) will support observing the mitigation zone for marine
     mammals while performing their regular duties.
Mitigation Requirements:
     Mitigation zone:

[[Page 72409]]

 
        --500 yd around the detonation site during activities using >0.5-
         2.5 lb net explosive weight.
     Prior to the initial start of the activity (starting 30
     minutes before the first planned detonation):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of detonations.
        --Navy personnel will ensure the mitigation zone is clear of
         marine mammals for 30 minutes prior to commencing a detonation.
        --A Navy biologist will serve as the lead Lookout and will make
         the final determination that the mitigation zone is clear of
         any biological resource sightings, including marine mammals,
         prior to the commencement of a detonation. The Navy biologist
         will maintain radio communication with the unit conducting the
         event and the other Lookout.
     During the activity:
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease detonations.
        --To the maximum extent practical depending on mission
         requirements, safety, and environmental conditions, boats will
         position themselves near the midpoint of the mitigation zone
         radius (but outside of the detonation plume and human safety
         zone), will position themselves on opposite sides of the
         detonation location (when two boats are used), and will travel
         in a circular pattern around the detonation location with one
         Lookout observing inward toward the detonation site and the
         other observing outward toward the perimeter of the mitigation
         zone.
        --Navy personnel will use only positively controlled charges
         (i.e., no time-delay fuses).
        --Navy personnel will use the smallest practicable charge size
         for each activity.
        --Activities will be conducted in Beaufort sea state number 2
         conditions or better and will not be conducted in low
         visibility conditions.
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         detonation) until one of the following conditions has been met:
         (1) The animal is observed exiting the mitigation zone; (2) the
         animal is thought to have exited the mitigation zone based on a
         determination of its course, speed, and movement relative to
         the detonation site; or (3) the mitigation zone has been clear
         from any additional sightings for 30 minutes.
     After each detonation and the completion of an activity
     (for 30 minutes):
        --Navy personnel will observe for marine mammals in the vicinity
         of where detonations occurred and immediately downstream of the
         detonation location; if any injured or dead marine mammals are
         observed, Navy personnel will follow established incident
         reporting procedures.
        --If additional platforms are supporting this activity (e.g.,
         providing range clearance), Navy personnel positioned on these
         assets will assist in the visual observation of the area where
         detonations occurred.
------------------------------------------------------------------------


           Table 45--Procedural Mitigation for Vessel Movement
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Vessel movement:
        --The mitigation will not be applied if: (1) The vessel's safety
         is threatened, (2) the vessel is restricted in its ability to
         maneuver (e.g., during launching and recovery of aircraft or
         landing craft, during towing activities, when mooring, and
         during Transit Protection Program exercises or other events
         involving escort vessels), (3) the vessel is submerged \1\ or
         operated autonomously, or (4) when impractical based on mission
         requirements (e.g., during test body retrieval by range craft).
Number of Lookouts and Observation Platform:
     1 Lookout on the vessel that is underway.
Mitigation Requirements:
     Mitigation zones:
        --500 yd around whales.
        --200 yd (for surface ships, which do not include small boats)
         around marine mammals other than whales (except bow-riding
         dolphins and pinnipeds hauled out on man-made navigational
         structures, port structures, and vessels).
        --100 yd (for small boats, such as range craft) around marine
         mammals other than whales (except bow-riding dolphins and
         pinnipeds hauled out on man-made navigational structures, port
         structures, and vessels).
     During the activity:
        --When underway, Navy personnel will observe the mitigation zone
         for marine mammals; if marine mammals are observed, Navy
         personnel will maneuver to maintain distance.
     Additional requirement:
        --If a marine mammal vessel strike occurs, Navy personnel will
         follow the established incident reporting procedures.
------------------------------------------------------------------------
\1\ NMFS has clarified in this final rule that this measure does not
  apply to submerged vessels. This does not change the scope of the
  mitigation measure, however, as the description of mitigation zones in
  the proposed rule as well as this rule explain that these zones apply
  to surface vessels and small boats, neither of which include submerged
  vessels.


       Table 46--Procedural Mitigation for Towed In-Water Devices
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Towed in-water devices:

[[Page 72410]]

 
        --Mitigation applies to devices that are towed from a manned
         surface platform or manned aircraft, or when a manned support
         craft is already participating in an activity involving in-
         water devices being towed by unmanned platforms.
        --The mitigation will not be applied if the safety of the towing
         platform or in-water device is threatened.
Number of Lookouts and Observation Platform:
     1 Lookout positioned on the towing platform or support
     craft.
Mitigation Requirements:
     Mitigation zones:
        --250 yd (for in-water devices towed by aircraft or surface
         ships) around marine mammals (except bow-riding dolphins and
         pinnipeds hauled out on man-made navigational structures, port
         structures, and vessels).
        --100 yd (for in-water devices towed by small boats, such as
         range craft) around marine mammals (except bow-riding dolphins
         and pinnipeds hauled out on man-made navigational structures,
         port structures, and vessels).
     During the activity (i.e., when towing an in-water device):
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         maneuver to maintain distance.
------------------------------------------------------------------------


 Table 47--Procedural Mitigation for Small-, Medium-, and Large-Caliber
                    Non-Explosive Practice Munitions
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Gunnery activities using small-, medium-, and large-caliber
     non-explosive practice munitions.
        --Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform:
     1 Lookout positioned on the platform conducting the
     activity.
     Depending on the activity, the Lookout could be the same as
     the one described for Procedural Mitigation for Weapons Firing
     Noise (Table 37).
Mitigation Requirements:
     Mitigation zone:
        --200 yd around the intended impact location.
     Prior to the initial start of the activity (e.g., when
     maneuvering on station):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of firing.
     During the activity:
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease firing.
     Commencement/recommencement conditions after a marine
     mammal sighting before or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         firing) until one of the following conditions has been met: (1)
         The animal is observed exiting the mitigation zone; (2) the
         animal is thought to have exited the mitigation zone based on a
         determination of its course, speed, and movement relative to
         the intended impact location; (3) the mitigation zone has been
         clear from any additional sightings for 10 minutes for aircraft-
         based firing or 30 minutes for vessel-based firing; or (4) for
         activities using a mobile target, the intended impact location
         has transited a distance equal to double that of the mitigation
         zone size beyond the location of the last sighting.
------------------------------------------------------------------------


       Table 48--Procedural Mitigation for Non-Explosive Missiles
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Aircraft-deployed non-explosive missiles.
     Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform:
     1 Lookout positioned in an aircraft.
Mitigation Requirements:
     Mitigation zone:
        --900 yd around the intended impact location.
     Prior to the initial start of the activity (e.g., during a
     fly-over of the mitigation zone):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of firing.
     During the activity:
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease firing.
     Commencement/recommencement conditions after a marine
     mammal sighting prior to or during the activity:

[[Page 72411]]

 
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         firing) until one of the following conditions has been met: (1)
         The animal is observed exiting the mitigation zone; (2) the
         animal is thought to have exited the mitigation zone based on a
         determination of its course, speed, and movement relative to
         the intended impact location; or (3) the mitigation zone has
         been clear from any additional sightings for 10 minutes when
         the activity involves aircraft that have fuel constraints, or
         30 minutes when the activity involves aircraft that are not
         typically fuel constrained.
------------------------------------------------------------------------


 Table 49--Procedural Mitigation for Non-Explosive Bombs and Mine Shapes
------------------------------------------------------------------------
                    Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
     Non-explosive bombs.
     Non-explosive mine shapes during mine laying activities.
Number of Lookouts and Observation Platform:
     1 Lookout positioned in an aircraft.
Mitigation Requirements:
     Mitigation zone:
        --1,000 yd around the intended target.
     Prior to the initial start of the activity (e.g., when
     arriving on station):
        --Navy personnel will observe the mitigation zone for floating
         vegetation; if floating vegetation is observed, Navy personnel
         will relocate or delay the start until the mitigation zone is
         clear.
        --Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         relocate or delay the start of bomb deployment or mine laying.
     During the activity (e.g., during approach of the target or
     intended minefield location):
        - Navy personnel will observe the mitigation zone for marine
         mammals; if marine mammals are observed, Navy personnel will
         cease bomb deployment or mine laying.
     Commencement/recommencement conditions after a marine
     mammal sighting prior to or during the activity:
        --Navy personnel will allow a sighted marine mammal to leave the
         mitigation zone prior to the initial start of the activity (by
         delaying the start) or during the activity (by not recommencing
         bomb deployment or mine laying) until one of the following
         conditions has been met: (1) The animal is observed exiting the
         mitigation zone; (2) the animal is thought to have exited the
         mitigation zone based on a determination of its course, speed,
         and movement relative to the intended target or minefield
         location; (3) the mitigation zone has been clear from any
         additional sightings for 10 minutes; or (4) for activities
         using mobile targets, the intended target has transited a
         distance equal to double that of the mitigation zone size
         beyond the location of the last sighting.
------------------------------------------------------------------------

Mitigation Areas

    In addition to procedural mitigation, the Navy will implement 
mitigation measures within mitigation areas to avoid or minimize 
potential impacts on marine mammals. A full technical analysis (for 
which the methods were discussed above) of the mitigation areas that 
the Navy considered for marine mammals is provided in Appendix K 
(Geographic Mitigation Assessment) of the 2020 NWTT FSEIS/OEIS. NMFS 
and the Navy took into account public comments received on the 2019 
NWTT DSEIS/OEIS and the 2020 NWTT proposed rule, best available 
science, and the practicability of implementing additional mitigation 
measures and has enhanced the mitigation areas and mitigation measures, 
beyond the 2015-2020 regulations, to further reduce impacts to marine 
mammals. Of note specifically, the 2015-2020 regulations included area-
specific mitigation in Puget Sound and coastal areas. Mitigation in 
Puget Sound included required approval from the Navy's U.S. Pacific 
Fleet's designated authority or System Command designated authority 
prior to MFAS training or pierside maintenance/testing of sonar 
systems, and required pierside maintenance and testing to be conducted 
in accordance with the Navy's Protective Measures Assessment Protocol 
(PMAP). Additionally, prior to Maritime Homeland Defense/Security Mine 
Countermeasure Integrated Exercises, the Navy was required to conduct 
pre-event planning and training to ensure environmental awareness of 
all exercise participants, and Navy event planners were required to 
consult with Navy biologists who contacted NMFS (Protected Resources 
Division, West Coast Marine Species Branch Chief) during the planning 
process in order to determine likelihood of gray whale or southern 
resident killer whale presence in the proposed exercise area as 
planners considered specifics of the event. Additionally, prior to 
Small Boat Attack training in Puget Sound, the Navy was also required 
to conduct pre-event planning and training to ensure environmental 
awareness of all exercise participants. When this event was proposed to 
be conducted in and around Naval Station Everett, Naval Base Kitsap 
Bangor, or Naval Base Kitsap Bremerton in Puget Sound, Navy event 
planners consulted with Navy biologists who contacted NMFS early in the 
planning process in order to determine the extent that marine mammals 
may have been present in the immediate vicinity of the proposed 
exercise area as planners considered the specifics of the event. 
Finally, the Navy continued an existing permission and approval process 
through the U.S. Third Fleet for in-water explosives training conducted 
at Hood Canal or Crescent Harbor. In coastal areas, the Navy conducted 
Missile Exercises using high explosives at least 50 nmi from shore in 
the NWTRC Offshore Area, conducted BOMBEX (high explosive munitions) 
events at least 50 nmi from shore, and conducted BOMBEX (non-explosive 
practice munitions) events at least 20 nmi from shore. Functionally, 
the protections provided by these mitigation area requirements from the 
previous rule have been carried forward into this rule (though they may 
be worded slightly differently) and, further, significant additional 
geographic mitigation has been added.
    Descriptions of the mitigation measures that the Navy will 
implement

[[Page 72412]]

within mitigation areas is provided in Table 50 (see below). The 
mitigation applies year-round unless specified otherwise in the table. 
The Changes from the Proposed Rule to the Final Rule section summarizes 
the mitigation area changes that have occurred since the proposed rule 
and the changes are further detailed in the descriptions of each 
mitigation area.
    NMFS conducted an independent analysis of the mitigation areas that 
the Navy will implement and that are included in this rule. NMFS' 
analysis indicates that the measures in these mitigation areas will 
reduce the likelihood or severity of adverse impacts to marine mammal 
species or their habitat in the manner described in this rule and are 
practicable for the Navy.
    Specifically, below we describe how certain activities are limited 
in feeding areas, migratory corridors, or other important habitat. To 
avoid repetition in those sections, we describe here how these measures 
reduce the likelihood or severity of effects on marine mammals and 
their habitat. As described previously, exposure to active sonar and 
explosive detonations has the potential to both disrupt behavioral 
patterns and reduce hearing sensitivity (temporarily or permanently, 
depending on the intensity and duration of the exposure). Disruption of 
feeding behaviors can have negative energetic consequences as a result 
of either obtaining less food in a given time or expending more energy 
(in the effort to avoid the stressor) to find the necessary food 
elsewhere, and extensive disruptions of this sort (especially over 
multiple sequential days) could accumulate in a manner that could 
negatively impact reproductive success or survival. By limiting impacts 
in known feeding areas, the overall severity of any take in those areas 
is reduced and the likelihood of impacts on reproduction or survival is 
further lessened. Similarly, reducing impacts on prey species, either 
by avoiding causing mortality or changing their expected distribution, 
can also lessen these sorts of detrimental energetic consequences. In 
migratory corridors, training and testing activities can result in 
additional energetic expenditures to avoid the loud sources--lessening 
training and testing in these areas also reduces the likelihood of 
detrimental energetic effects. In all of the mitigation areas, inasmuch 
as the density of certain species may be higher at certain times, a 
selective reduction of training and testing activities in those higher-
density areas and times is expected to lessen the magnitude of take 
overall, as well as the specific likelihood of hearing impairment or 
vessel strike.
    Regarding operational practicability, NMFS is heavily reliant on 
the Navy's description and conclusions, since the Navy is best equipped 
to describe the degree to which a given mitigation measure affects 
personnel safety or mission effectiveness, and is practical to 
implement. The Navy considers the measures in this rule to be 
practicable, and NMFS concurs.

  Table 50--Geographic Mitigation Areas for Marine Mammals in the NWTT
                               Study Area
------------------------------------------------------------------------
                       Mitigation Area Description
-------------------------------------------------------------------------
Stressor or Activity:
     Sonar (mitigation does not apply to active sonar sources
     used for safety of navigation).
     Explosives.
     Physical disturbance and strikes.
Resource Protection Focus:
     Marine mammals (humpback whale, gray whale, Southern
     Resident killer whale, harbor porpoise).
     Fish (including Chinook salmon).
Mitigation Requirements: \1\
     Marine Species Coastal Mitigation Area (year-round or
     seasonal if specified):
        --Within 50 nmi from shore in the Marine Species Coastal
         Mitigation Area:
            [ssquf] The Navy will not conduct explosive training
             activities.
            [ssquf] The Navy will not conduct explosive testing
             activities (except explosive Mine Countermeasure and
             Neutralization Testing).
            [ssquf] The Navy will not conduct non-explosive missile
             training activities.
            [ssquf] The Navy will issue annual seasonal awareness
             notification messages to alert Navy ships and aircraft to
             the possible presence of increased concentrations of
             Southern Resident killer whales from December 1 to June 30,
             humpback whales from May 1 through December 31, and gray
             whales from May 1 to November 30. For safe navigation and
             to avoid interactions with large whales, the Navy will
             instruct vessels to remain vigilant to the presence of
             Southern Resident killer whales, humpback whales, and gray
             whales that may be vulnerable to vessel strikes or
             potential impacts from training and testing activities.
             Platforms will use the information from the awareness
             notification messages to assist their visual observation of
             applicable mitigation zones during training and testing
             activities and to aid in the implementation of procedural
             mitigation.\2\
        --Within 20 nmi from shore in the Marine Species Coastal
         Mitigation Area:
            [ssquf] The Navy will conduct no more than a total of 33
             hours of surface ship hull-mounted MF1 mid-frequency active
             sonar during testing annually within 20 nmi from shore in
             the Marine Species Coastal Mitigation Area, in the Juan de
             Fuca Eddy Marine Species Mitigation Area, and in the
             Olympic Coast National Marine Sanctuary Mitigation Area
             combined.
            [ssquf] To the maximum extent practical, the Navy will
             conduct explosive Mine Countermeasure and Neutralization
             Testing from July 1 through September 30 when operating
             within 20 nmi from shore.
            [ssquf] From October 1 through June 30, the Navy will
             conduct a maximum of one explosive Mine Countermeasure and
             Neutralization Testing event, not to exceed the use of 20
             explosives from bin E4 and 3 explosives from bin E7
             annually, and not to exceed the use of 60 explosives from
             bin E4 and 9 explosives from bin E7 over the seven-year
             period of the rule.
            [ssquf] The Navy will not conduct non-explosive large-
             caliber gunnery training activities.
            [ssquf] The Navy will not conduct non-explosive bombing
             training activities.
        --Within 12 nmi from shore in the Marine Species Coastal
         Mitigation Area:
            [ssquf] The Navy will not conduct Anti-Submarine Warfare
             Tracking Exercise--Helicopter,--Maritime Patrol Aircraft,--
             Ship, or--Submarine training activities (which involve the
             use of mid-frequency or high-frequency active sonar).
            [ssquf] The Navy will not conduct non-explosive Anti-
             Submarine Warfare Torpedo Exercise--Submarine training
             activities (which involve the use of mid-frequency or high-
             frequency active sonar).
            [ssquf] The Navy will conduct a maximum of one Unmanned
             Underwater Vehicle Training event per year within 12 nmi
             from shore at the Quinault Range Site. In addition,
             Unmanned Underwater Vehicle Training events within 12 nmi
             from shore at the Quinault Range Site will be cancelled or
             moved to another training location if Southern Resident
             killer whales are detected at the planned training location
             during the event planning process, or immediately prior to
             the event, as applicable.

[[Page 72413]]

 
            [ssquf] During explosive Mine Countermeasure and
             Neutralization Testing, the Navy will not use explosives in
             bin E7 closer than 6 nmi from shore in the Quinault Range
             Site.
            [ssquf] The Navy will not conduct non-explosive small- and
             medium-caliber gunnery training activities.
             Olympic Coast National Marine Sanctuary Mitigation
             Area (year-round):
        --Within the Olympic Coast National Marine Sanctuary Mitigation
         Area:
            [ssquf] The Navy will conduct a maximum of 32 hours of
             surface ship hull-mounted MF1 mid-frequency active sonar
             during training annually.
            [ssquf] The Navy will conduct no more than a total of 33
             hours of surface ship hull-mounted MF1 mid-frequency active
             sonar during testing annually within 20 nmi from shore in
             the Marine Species Coastal Mitigation Area, in the Juan de
             Fuca Eddy Marine Species Mitigation Area, and in the
             Olympic Coast National Marine Sanctuary Mitigation Area
             combined.
            [ssquf] The Navy will not conduct explosive Mine
             Countermeasure and Neutralization Testing activities.
            [ssquf] The Navy will not conduct non-explosive bombing
             training activities.
     Juan de Fuca Eddy Marine Species Mitigation Area (year-
     round):
        --Within the Juan de Fuca Eddy Marine Species Mitigation Area:
            [ssquf] The Navy will conduct no more than a total of 33
             hours of surface ship hull-mounted MF1 mid-frequency active
             sonar during testing annually within 20 nmi from shore in
             the Marine Species Coastal Mitigation Area, in the Juan de
             Fuca Eddy Marine Species Mitigation Area, and in the
             Olympic Coast National Marine Sanctuary Mitigation Area
             combined.
            [ssquf] The Navy will not conduct explosive Mine
             Countermeasure and Neutralization Testing activities.
     Stonewall and Heceta Bank Humpback Whale Mitigation Area
     (May 1-November 30):
        --Within the Stonewall and Heceta Bank Humpback Whale Mitigation
         Area from May 1 to November 30:
            [ssquf] The Navy will not use surface ship hull-mounted MF1
             mid-frequency active sonar during training or testing.
            [ssquf] The Navy will not conduct explosive Mine
             Countermeasure and Neutralization Testing.
     Point St. George Humpback Whale Mitigation Area (July 1-
     November 30):
        --Within the Point St. George Humpback Whale Mitigation Area
         from July 1 to November 30:
            [ssquf] The Navy will not use surface ship hull-mounted MF1
             mid-frequency active sonar during training or testing.
            [ssquf] The Navy will not conduct explosive Mine
             Countermeasure and Neutralization Testing.
     Northern Puget Sound Gray Whale Mitigation Area (March 1-
     May 31):
        --Within the Northern Puget Sound Gray Whale Mitigation Area
         from March 1 to May 31:
            [ssquf] The Navy will not conduct Civilian Port Defense--
             Homeland Security Anti-Terrorism/Force Protection
             Exercises.
     Puget Sound and Strait of Juan de Fuca Mitigation Area
     (year-round or seasonal if specified):
        --Within the Puget Sound and Strait of Juan de Fuca Mitigation
         Area:
            [ssquf] The Navy will not use low-frequency, mid-frequency,
             or high-frequency active sonar during training or testing
             within the Puget Sound and Strait of Juan de Fuca
             Mitigation Area, unless a required element (i.e., a
             criterion necessary for the success of the event)
             necessitates that the activity be conducted in NWTT Inland
             Waters during (1) Unmanned Underwater Vehicle Training, (2)
             Civilian Port Defense--Homeland Security Anti-Terrorism/
             Force Protection Exercises, (3) activities conducted by
             Naval Sea Systems Command at designated locations, or (4)
             pierside sonar maintenance or testing at designated
             locations.
            [ssquf] The Navy will use the lowest active sonar source
             levels practical to successfully accomplish each event.
            [ssquf] Naval units will obtain permission from the
             appropriate designated Command authority prior to
             commencing pierside maintenance or testing with hull-
             mounted mid-frequency active sonar.
            [ssquf] The Navy will conduct a maximum of one Unmanned
             Underwater Vehicle Training activity annually at the Navy 3
             OPAREA, Navy 7 OPAREA, and Manchester Fuel Depot (i.e., a
             maximum of one event at each location).
            [ssquf] The Navy will not use explosives during testing.
            [ssquf] The Navy will not use explosives during training
             except at the Hood Canal EOD Range and Crescent Harbor EOD
             Range during explosive mine neutralization activities
             involving the use of Navy divers.
            [ssquf] The Navy will not use explosives in bin E4 (>2.5-5
             lb. net explosive weight) or above, and will instead use
             explosives in bin E0 (<0.1 lb. net explosive weight) or bin
             E3 (>0.5-2.5 lb. net explosive weight).
            [ssquf] During February, March, and April at the Hood Canal
             EOD Range, the Navy will not use explosives in bin E3 (>0.5-
             2.5 lb. net explosive weight), and will instead use
             explosives in bin E0 (<0.1 lb. net explosive weight).
            [ssquf] During August, September, and October at the Hood
             Canal EOD Range, the Navy will avoid using explosives in
             bin E3 (>0.5-2.5 lb. net explosive weight) and will instead
             use explosives in bin E0 (<0.1 lb. net explosive weight) to
             the maximum extent practical unless necessitated by mission
             requirements.
            [ssquf] At the Crescent Harbor EOD Range, the Navy will
             conduct explosive activities at least 1,000 m from the
             closest point of land.
            [ssquf] The Navy will not conduct non-explosive live fire
             events in the mitigation area (except firing blank
             weapons), including gunnery exercises, missile exercises,
             torpedo exercises, bombing exercises, and Kinetic Energy
             Weapon Testing.
            [ssquf] Navy event planners will coordinate with Navy
             biologists during the event planning process prior to
             conducting (1) Unmanned Underwater Vehicle Training at the
             NAVY 3 OPAREA, Manchester Fuel Depot, Crescent Harbor
             Explosive Ordnance Disposal Range, and NAVY 7 OPAREA (for
             Southern Resident killer whales), (2) Civilian Port
             Defense--Homeland Security Anti-Terrorism/Force Protection
             Exercises (for Southern Resident killer whales and gray
             whales), (3) explosive mine neutralization activities
             involving the use of Navy divers (for Southern Resident
             killer whales), and (4) Small Boat Attack Exercises, which
             involve firing blank small-caliber weapons (for Southern
             Resident killer whales and gray whales). Navy biologists
             will work with NMFS and will initiate communication with
             the appropriate marine mammal detection networks to
             determine the likelihood of applicable marine mammal
             species presence in the planned training location. Navy
             biologists will notify event planners of the likelihood of
             species presence. To the maximum extent practical, Navy
             planners will use this information when planning specific
             details of the event (e.g., timing, location, duration) to
             avoid planning activities in locations or seasons where
             species presence is expected. The Navy will ensure
             environmental awareness of event participants.
             Environmental awareness will help alert participating crews
             to the possible presence of applicable species in the
             training location. Lookouts will use the information to
             assist visual observation of applicable mitigation zones
             and to aid in the implementation of procedural mitigation.
             In addition, Unmanned Underwater Vehicle Training events at
             the NAVY 3 OPAREA, Manchester Fuel Depot, Crescent Harbor
             Explosive Ordnance Disposal Range, and NAVY 7 OPAREA will
             be cancelled or moved to another training location if the
             presence of Southern Resident killer whales is reported
             through available monitoring networks during the event
             planning process, or immediately prior to the event, as
             applicable.

[[Page 72414]]

 
            [ssquf] The Navy will issue annual seasonal awareness
             notification messages to alert Navy ships and aircraft
             operating within the Puget Sound and Strait of Juan de Fuca
             Mitigation Area to the possible presence of concentrations
             of Southern Resident killer whales from July 1 to November
             30 in the Puget Sound and Strait of Juan de Fuca, and
             concentrations of gray whales from March 1 to May 31 in the
             Strait of Juan de Fuca and northern Puget Sound. For safe
             navigation and to avoid interactions with large whales, the
             Navy will instruct vessels to remain vigilant to the
             presence of Southern Resident killer whales and gray whales
             that may be vulnerable to vessel strikes or potential
             impacts from training and testing activities. Platforms
             will use the information from the awareness notification
             messages to assist their visual observation of applicable
             mitigation zones during training and testing activities and
             to aid in the implementation of procedural mitigation.
------------------------------------------------------------------------
\1\ Should national security present a requirement to conduct training
  or testing prohibited by the mitigation requirements specified in this
  table, naval units must obtain permission from the appropriate
  designated Command authority prior to commencement of the activity.
  The Navy will provide NMFS with advance notification and include
  relevant information about the event (e.g., sonar hours, explosives
  use, non-explosive practice munitions use) in its annual activity
  reports to NMFS.
\2\ The Navy will send these notification messages to all units
  operating throughout the NWTT Study Area.

BILLING CODE 3510-22-P

[[Page 72415]]

[GRAPHIC] [TIFF OMITTED] TR12NO20.000

BILLING CODE 3510-22-C
Marine Species Coastal Mitigation Area
    Within 50 nmi from shore--The 50 nmi from shore portion of the 
Marine Species Coastal Mitigation Area overlaps important feeding, 
migration, and/or proposed ESA critical habitat for humpback whale, 
gray whale, Southern Resident killer whale, and harbor porpoise. The 
Olympic Coast National Marine Sanctuary and Quinault, Grays, Guide, 
Willapa, Astoria, and Eel canyons are also located within 50 nmi from 
shore in the Marine Species Coastal Mitigation Area.
    See Table 50 for the specific mitigation measures. Mitigation 
within 50 nmi from shore will result in an

[[Page 72416]]

avoidance of potential impacts on marine mammals within their important 
habitat areas from all explosive training activities, all explosive 
testing activities except explosive Mine Countermeasure and 
Neutralization Testing activities, and non-explosive missile training 
exercises. Additionally, this mitigation will eliminate impacts from 
active sonar used in conjunction with these prohibited activities, such 
as mid-frequency and high-frequency active sonar used during explosive 
torpedo events (e.g., MF1 and MF4 sonar during Torpedo [Explosive] 
Testing).
    Since publication of the proposed rule, an additional measure has 
been added in this mitigation area that requires the Navy to issue 
annual seasonal awareness notification messages to further help avoid 
potential impacts from vessel strikes and training and testing 
activities on humpback whales, gray whales, and Southern Resident 
killer whales in the Marine Species Coastal Mitigation Area. The 
awareness notification messages will coincide with the seasons in which 
humpback whales, gray whales, and Southern Resident killer whales are 
most likely to be observed in concentrations in the mitigation area. 
Southern Resident killer whales are most likely to be observed in the 
NWTT Offshore Area in winter and spring (December 1 to June 30), due to 
prey availability. Gray whales and humpback whales are most likely to 
be observed in the NWTT Offshore Area from late spring through fall 
(May 1 to November 30 and May 1 through December 31, respectively), 
which correlates to feeding or migration seasons.
    Within 20 nmi from shore--The 20 nmi from shore portion of the 
Marine Species Coastal Mitigation Area overlaps important feeding, 
migration, or ESA-designated critical habitat, as described in Section 
K.3.2.1 of the 2020 FSEIS/OEIS (Resource Description), for gray whales, 
humpback whales, and Southern Resident killer whales. The mitigation 
area also overlaps a significant portion of the Olympic Coast National 
Marine Sanctuary, and Astoria and Eel canyons.
    See Table 50 for the specific mitigation measures. As included in 
the proposed rule, mitigation requirements within 20 nmi from shore 
will (in addition to the avoided impacts described above for within 50 
nmi) avoid or reduce potential impacts on marine mammals within these 
habitats from non-explosive large-caliber gunnery training and non-
explosive bombing training. Additionally, since publication of the 
proposed rule, a measure has been added limiting the Navy from 
conducting more than a total of 33 hours of surface ship hull-mounted 
MF1 mid-frequency active sonar during testing annually within 20 nmi 
from shore in the Marine Species Coastal Mitigation Area, in the Juan 
de Fuca Eddy Marine Species Mitigation Area, and in the Olympic Coast 
National Marine Sanctuary Mitigation Area combined.
    Mitigation has also been added to limit explosive Mine 
Countermeasure and Neutralization Testing events in this area during 
certain times of year and limit the number of explosives in each event. 
This mitigation is designed primarily to avoid or reduce potential 
impacts on ESA-listed fish species based on their typical occurrence 
seasonally and at certain water depths (see the 2020 NWTT FSEIS/OEIS 
for depth considerations). The mitigation may also benefit feeding or 
migrating humpback whales, migrating gray whales, and feeding or 
transiting Southern Resident killer whales. One of these new mitigation 
measures requires the Navy to conduct explosive Mine Countermeasure and 
Neutralization Testing from July 1 through September 30 to the maximum 
extent practical when operating within 20 nmi from shore. An additional 
new measure requires that the Navy can only conduct a maximum of one 
explosive Mine Countermeasure and Neutralization Testing event annually 
from October 1 through June 30, not to exceed the use of 20 explosives 
from bin E4 and 3 explosives from bin E7 annually, and not to exceed 
the use of 60 explosives from bin E4 and 9 explosives from bin E7 over 
the seven-year period of the rule. The new limit on the number of 
explosives used annually and over the seven-year period is designed 
primarily to reduce potential impacts on ESA-listed fish, including 
Chinook salmon, the preferred prey source of Southern Resident Killer 
Whales. This mitigation will reduce the maximum potential exposure to 
explosives in bin E4 and bin E7 by approximately 40 percent in the 
months and locations where ESA-listed fish species (some of which are 
prey species for killer whales), including Chinook salmon Upper 
Columbia River Spring-Run Evolutionarily Significant Unit, and Chinook 
salmon Central Valley Spring-Run Evolutionarily Significant Unit, are 
expected to be present in the NWTT Offshore Area.
    Within 12 nmi from shore--The 12 nmi from shore portion of the 
Marine Species Coastal Mitigation Area overlaps important feeding, 
migration, and ESA-designated critical habitat for gray whales, 
humpback whales, and Southern Resident killer whales, as described in 
Section K.3.2.1 (Resource Description) of the 2020 FSEIS/OEIS. 
Additionally, part of the Marine Species Coastal Mitigation Area within 
12 nmi from shore overlaps a portion of the Olympic Coast National 
Marine Sanctuary.
    See Table 50 for the specific mitigation measures. As described in 
the proposed rule, mitigation requirements within 12 nmi from shore 
(which apply in addition to the measures described above for within 50 
nmi and within 20 nmi from shore) prohibit non-explosive small- and 
medium-caliber gunnery training activities and Anti-Submarine Warfare 
Tracking Exercise--Helicopter, Maritime Patrol Aircraft, Ship, or 
Submarine training activities (which involve mid-frequency active sonar 
[including surface ship hull-mounted MF1 mid-frequency active sonar and 
MF4 dipping sonar] and high-frequency active sonar). Additionally, new 
mitigation since publication of the proposed rule prohibits non-
explosive Anti-Submarine Warfare Torpedo Exercise--Submarine training 
activities (which involves mid-frequency and high-frequency active 
sonar) within this area. We expect these measures to result in an 
avoidance of potential impacts to marine mammals from these activities.
    Since publication of the proposed rule, another additional measure 
has been added, limiting the Navy to conducting a maximum of one 
Unmanned Underwater Vehicle Training event per year within 12 nmi from 
shore at the Quinault Range Site, and requiring the Navy to cancel or 
move Unmanned Underwater Vehicle Training events if Southern Resident 
killer whales are detected within 12 nmi from shore at the Quinault 
Range Site. This measure is expected to help avoid any potential 
impacts on Southern Resident killer whales during Unmanned Underwater 
Vehicle Training events.
    Within 6 nmi from shore--Finally, in addition to the mitigation 
measures described above, new mitigation during explosive Mine 
Countermeasure and Neutralization Testing prohibits the use of 
explosives in bin E7 closer than 6 nmi from shore in the Quinault Range 
Site. This measure is primarily designed to avoid overlap of the larger 
of the explosive bins used in this activity with ESA-listed fish 
species, including Chinook salmon, which are an important prey species 
for killer whales.
Olympic Coast National Marine Sanctuary Mitigation Area
    Mitigation within the Olympic Coast National Marine Sanctuary 
Mitigation

[[Page 72417]]

Area is designed to avoid or reduce potential impacts from surface ship 
hull-mounted MF1 mid-frequency active sonar, explosives during Mine 
Countermeasure and Neutralization Testing activities, and non-explosive 
practice munitions during non-explosive bombing training in important 
feeding or migration habitat for gray whales, humpback whales, Southern 
Resident killer whales, and other sanctuary resources, including 
Chinook salmon, which serve as an important prey species for killer 
whales. Mitigation within the Olympic Coast National Marine Sanctuary 
Mitigation Area may avoid or reduce impacts to other marine mammal 
species that inhabit, forage in, and migrate through the sanctuary. As 
detailed in Section 6.1.2.1 (Olympic Coast National Marine Sanctuary) 
of the 2015 NWTT Final EIS/OEIS, the Olympic Coast National Marine 
Sanctuary consists of an area of 2,408 square nmi of marine waters and 
the submerged lands off the Olympic Peninsula Coastline of Washington. 
The sanctuary extends approximately 38 nmi seaward, covering much of 
the continental shelf and the Quinault Canyon. Due to the Juan de Fuca 
Eddy ecosystem created from localized currents at the entrance to the 
Strait of Juan de Fuca and the diversity of bottom habitats, the 
Olympic Coast National Marine Sanctuary supports a variety of marine 
life. The diversity of habitats, and the nutrient-rich upwelling zone 
(which exhibits the greatest volume of upwelling in North America) that 
drives high primary productivity in this area, contribute to the high 
species diversity in the Olympic Coast National Marine Sanctuary. 
According to the Office of National Marine Sanctuaries (2008), the 
Sanctuary provides important foraging and migration habitat for 29 
species of marine mammals.
    As included in the proposed rule, the Navy will conduct a maximum 
of 32 hours annually of surface ship hull-mounted MF1 mid-frequency 
active sonar during training in the Olympic Coast National Marine 
Sanctuary Mitigation Area. Additionally, since publication of the 
proposed rule, and as discussed in the Marine Species Coastal 
Mitigation Area section above, an additional measure has been added 
limiting the Navy from conducting more than a total of 33 hours of 
surface ship hull-mounted MF1 mid-frequency active sonar during testing 
annually within 20 nmi from shore in the Marine Species Coastal 
Mitigation Area, in the Juan de Fuca Eddy Marine Species Mitigation 
Area, and in the Olympic Coast National Marine Sanctuary Mitigation 
Area combined.
    As included in the proposed rule, the Navy will not conduct 
explosive Mine Countermeasure and Neutralization Testing activities or 
non-explosive bombing training activities in the Olympic Coast National 
Marine Sanctuary Mitigation Area. Because this mitigation area is 
located entirely within 50 nmi from shore in the Marine Species Coastal 
Mitigation Area, the combined mitigation will ensure that marine 
mammals and their habitat are not exposed to explosives in the 
Sanctuary from any training or testing activities. Furthermore, 
additive mitigation within 20 nmi and 12 nmi from shore in the Marine 
Species Coastal Mitigation Area will help further avoid or reduce 
potential impacts from active sonar and non-explosive practice 
munitions on Sanctuary resources.
Juan de Fuca Eddy Marine Species Mitigation Area
    The Juan de Fuca Eddy system is located off Cape Flattery and 
contains elevated macronutrient levels from spring to fall, derived 
primarily from upwelling of nutrient-rich deep waters from the 
California Undercurrent combined with lesser contributions from the 
Strait of Juan de Fuca outflow (MacFadyen et al., 2008). Mitigation 
within the Juan de Fuca Eddy Marine Species Mitigation Area is designed 
to avoid or reduce potential impacts from surface ship hull-mounted MF1 
mid-frequency active sonar and explosives during Mine Countermeasure 
and Neutralization Testing activities on Southern Resident killer 
whales and humpback whales within important migration and feeding 
habitats. The Navy will not conduct explosive Mine Countermeasure and 
Neutralization Testing activities in this mitigation area, and will 
conduct no more than a total of 33 hours of surface ship hull-mounted 
MF1 mid-frequency active sonar during testing annually within 20 nmi 
from shore in the Marine Species Coastal Mitigation Area, in the Juan 
de Fuca Eddy Marine Species Mitigation Area, and in the Olympic Coast 
National Marine Sanctuary Mitigation Area combined.
    Additional measures were considered in this area, however, NMFS 
determined that additional measures were not warranted, given that the 
Navy does not generally schedule other training and testing activities 
in this portion of the Study Area due to the high volume of commercial 
vessel traffic. Therefore the potential for impacts to marine mammals 
is low. As described in Section K.3.2.2.2 (Operational Assessment) of 
the 2020 NWTT FSEIS/OEIS, when scheduling activities, the Navy 
considers the need to minimize sea space and airspace conflicts between 
its own activities and other users with consideration for public 
safety.
    Waters within the Juan de Fuca Eddy Marine Species Mitigation Area 
(including areas off Cape Flattery) are important foraging habitat for 
aggregations of humpback whales and migration habitat for Southern 
Resident killer whales as they transit between Inland Waters and the 
Offshore Area (see Section K.3.2.1.1 (Humpback Whale) and Section 
K.3.2.1.3 (Southern Resident Killer Whale) of the 2020 FSEIS/OEIS). The 
full extent of the Juan de Fuca Eddy is not incorporated into the 
Northern Washington humpback whale biologically important feeding area 
because the development of biologically important areas was restricted 
to U.S. waters only. Therefore, the Northern Washington biologically 
important humpback whale feeding area extends northward to the boundary 
of the U.S. Exclusive Economic Zone (Calambokidis et al., 2015; 
Ferguson et al., 2015a; Ferguson et al., 2015b). However, humpback 
whale aggregations feed across this political boundary in the nutrient 
rich waters throughout the Juan de Fuca Eddy. Therefore, waters within 
the Juan de Fuca Eddy between the Northern Washington humpback whale 
biologically important area and the northern boundary of the NWTT 
Offshore Area are included in the Juan de Fuca Eddy Marine Species 
Mitigation Area.
    Migrating gray whales may also use this area, as well as other 
species of marine mammals, including sperm whales. Sperm whale 
concentrations typically correlate with areas of high productivity near 
drop-offs and areas with strong currents and steep topography (Gannier 
and Praca, 2007; Jefferson et al., 2015), such as the conditions 
present seasonally in the Juan de Fuca Eddy (MacFadyen et al., 2008). 
The mitigation area's nutrient-rich waters and seasonal upwelling 
provide an abundance of marine mammal prey species and favorable 
foraging conditions for concentrations of marine mammals. The 
mitigation will also help avoid or reduce potential impacts on other 
species, including Southern Resident killer whale preferred prey, 
Chinook salmon.
Stonewall and Heceta Bank Humpback Whale Mitigation Area
    Mitigation in the Stonewall and Heceta Bank Humpback Whale 
Mitigation Area, which is required from

[[Page 72418]]

May 1 to November 30, is primarily designed to avoid or reduce 
potential impacts from surface ship hull-mounted MF1 mid-frequency 
active sonar and explosive Mine Countermeasure and Neutralization 
Testing activities to humpback whales in an important seasonal feeding 
area. See Table 50 for the specific mitigation measures.
    The Stonewall and Heceta Bank Humpback Whale Mitigation Area is 
within 50 nmi from shore in the Marine Species Coastal Mitigation Area. 
Therefore, given the combined mitigation in these two areas, no 
explosive training or testing will occur in this mitigation area from 
May 1 to November 30. Additionally, a portion of the Stonewall and 
Heceta Bank Humpback Whale Mitigation Area is within 20 nmi from shore 
in the Marine Species Coastal Mitigation Area. Mitigation measures 
between these two areas will help further reduce potential impacts from 
additional sources of active sonar, as well as non-explosive practice 
munitions, year round, given that the Marine Species Coastal Mitigation 
Area is effective year round.
    From May to November, humpback whales aggregate to feed on krill 
and small fish in this area. Enhanced vertical and horizontal mixing 
associated with Heceta Bank results in higher prey densities, which 
improves foraging conditions for humpback whales and harbor porpoise 
(Tynan et al., 2005). Humpback whales and harbor porpoise aggregate in 
this area in the summer when prey concentrations are thought to be 
highest.
    In addition to containing humpback whale and harbor porpoise 
feeding habitat, the Stonewall and Heceta Bank Humpback Whale 
Mitigation Area overlaps important habitats for several other species, 
including potential gray whale migration habitat; Southern Resident 
killer whale feeding, migration and proposed ESA critical habitat; and 
Chinook salmon migration habitat. Other marine mammal species have also 
been observed in the vicinity of Heceta Bank. The enhanced vertical and 
horizontal mixing associated with Heceta Bank that results in higher 
prey densities and improved foraging conditions for humpback whales and 
harbor porpoise may also serve to influence the presence of other 
marine mammal species in this area (Tynan et al., 2005). For example, 
sperm whales, Baird's beaked whales, Cuvier's beaked whales, Pacific 
white-sided dolphins, northern right whale dolphins, Risso's dolphins, 
and Dall's porpoise have been observed at Heceta Bank in spring or 
summer during past surveys (Tynan et al., 2005). Sperm whales have been 
observed at Heceta Bank during spring and summer, possibly indicating a 
correlation between the abundance of prey species, such as large 
cephalopods (e.g., squid) and fish (Tynan et al., 2005). Therefore, in 
addition to benefits to humpback whales and harbor porpoise in 
important foraging habitat, mitigation within the Stonewall and Heceta 
Bank Humpback Whale Mitigation Area will likely help avoid or reduce 
potential impacts to additional marine mammal species that may feed in 
or migrate through this area.
Point St. George Humpback Whale Mitigation Area
    The Point St. George Humpback Whale Mitigation area contains 
important humpback whale feeding habitat. From July to November, 
humpback whales feed in an area off of Oregon and California at Point 
St. George, an area that has similar productive upwelling conditions as 
Heceta Bank. Additionally, the area overlaps important habitats for 
several other species, including potential gray whale migration habitat 
and Southern Resident killer whale feeding and migration habitat. 
Migrating Chinook salmon may occur in this area as well.
    Mitigation in the Point St. George Humpback Whale Mitigation Area, 
effective from July 1 to November 30, was initially designed to avoid 
or reduce potential impacts from mid-frequency active sonar on humpback 
whales, as this is an important seasonal feeding area. Since the 
proposed rule, an additional measure has been added that prohibits the 
Navy from conducting explosive Mine Countermeasure and Neutralization 
Testing activities in this mitigation area.
    The Point St. George Humpback Whale Mitigation Area is located 
entirely within 20 nmi from shore in the Marine Species Coastal 
Mitigation Area. Therefore, given the combined mitigation in these two 
areas, no explosive training or testing will occur in the Point St. 
George Humpback Whale Mitigation Area from July 1 to November 30. 
Additionally, potential impacts to marine mammals from surface ship 
hull-mounted MF1 mid-frequency active sonar as well as non-explosive 
practice munitions will be avoided or reduced year round.
Northern Puget Sound Gray Whale Mitigation Area
    The Northern Puget Sound Gray Whale Mitigation Area fully overlaps 
the biologically important gray whale feeding habitat identified by 
Calambokidis et al. (2015) and a portion of the gray whale migration 
biologically important area. Gray whales feed in this area from March 1 
to May 31. The Navy will not conduct Civilian Port Defense--Homeland 
Security Anti-Terrorism/Force Protection Exercises during this same 
time period (March 1 to May 31) in this mitigation area. Civilian Port 
Defense--Homeland Security Anti-Terrorism/Force Protection Exercises 
are multi-day events that involve aircraft, surface vessels, and 
unmanned underwater vehicles using high-frequency active sonar and 
other systems to train to detect non-explosive underwater mine shapes. 
Therefore, with the Navy restricted from conducting this activity in 
the Northern Puget Sound Gray Whale Mitigation Area during the 
specified time period, potential impacts from vessel movements, towed 
in-water devices, and active sonar on gray whales will be avoided 
during important times in this feeding area.
    The Northern Puget Sound Gray Whale Mitigation Area is located 
entirely within the Puget Sound and Strait of Juan de Fuca Mitigation 
Area. Therefore, mitigation in the Puget Sound and Strait of Juan de 
Fuca Mitigation Area, described below, will further reduce potential 
impacts on gray whale feeding in this location.
Puget Sound and Strait of Juan de Fuca Mitigation Area
    The Puget Sound and Strait of Juan de Fuca Mitigation Area 
encompasses the full extent of NWTT Inland Waters and, therefore, the 
mitigation area fully overlaps each known important marine mammal 
feeding and migration habitat area in NWTT inland waters. (See Section 
K.3.3.1 (Resource Description) of the 2020 FSEIS/OEIS for a full 
description of these areas.) This includes feeding and potential 
migration habitat for gray whales and ESA-designated critical habitat 
for Southern Resident killer whales, as well as for one of the Southern 
Resident killer whales' primary sources of prey, Puget Sound Chinook 
salmon. Mitigation in the Puget Sound and Strait of Juan de Fuca 
Mitigation Area is designed to minimize potential impacts on these 
species and their habitat in NWTT Inland Waters. See Table 50 for the 
specific mitigation measures.
    As included in the proposed rule, naval units are required to 
obtain approval from the appropriate designated Command authority prior 
to commencing pierside maintenance or testing with hull-mounted mid-
frequency active sonar. This measure will elevate the situational and 
environmental awareness of respective Command authorities during the 
event

[[Page 72419]]

planning process. Requiring designated Command authority approval 
provides an increased level of assurance that mid-frequency active 
sonar is a required element (i.e., a criterion necessary for the 
success of the event) for each event. Such authorizations are typically 
based on the unique characteristics of the area from a military 
readiness perspective, taking into account the importance of the area 
for marine species and the need to mitigate potential impacts on 
Southern Resident killer whales (and other marine mammals, such as gray 
whales) to the maximum extent practical.
    Also included in the proposed rule, year-round mitigation at the 
Crescent Harbor Explosive Ordnance Disposal (EOD) Range prohibits 
explosive activities within 1,000 m of the closest point of land. This 
measure is primarily intended to avoid or reduce potential impacts on 
bull trout, however, it may also benefit other species, such as 
Southern Resident killer whales (although they have not been observed 
regularly at the Crescent Harbor EOD Range), gray whales, and Puget 
Sound Chinook salmon. Finally, as also included in the proposed rule, 
for Civilian Port Defense--Homeland Security Anti-Terrorism/Force 
Protection Exercises, Navy event planners will coordinate with Navy 
biologists during the event planning process. Navy biologists will work 
with NMFS to determine the likelihood of gray whale and Southern 
Resident killer whale presence in the planned training location. Navy 
biologists will notify event planners of the likelihood of killer whale 
and gray whale presence as they plan specific details of the event 
(e.g., timing, location, duration), with the goal of minimizing impacts 
to killer whales and gray whales through the adjustment of event 
details, where practical. The Navy will also ensure environmental 
awareness of event participants. Environmental awareness will help 
alert participating ship and aircraft crews to the possible presence of 
marine mammals in the training location, such as gray whales and 
Southern Resident killer whales.
    As described previously, this final rule includes many new 
mitigation measures in the Puget Sound and Strait of Juan de Fuca 
Mitigation Area to further protect marine mammals, particularly 
Southern Resident killer whales. The Assessment of Mitigation Measures 
for NWTT Study Area section describes mitigation that is new to this 
final rule, and distinguishes between new mitigation that is a 
continuation of the Navy's voluntary Phase II mitigation, and new 
measures that were not implemented by the Navy in NWTT Phase II. See 
that section and Table 50 for all other mitigation measures.
    New mitigation in the Puget Sound and Strait of Juan de Fuca 
Mitigation Area is designed to help avoid any potential impacts from 
training and testing on Southern Resident killer whales in NWTT Inland 
Waters. With implementation of these new mitigation measures, we do not 
anticipate any take of Southern Resident killer whales in NWTT Inland 
Waters due to NWTT training and testing activities. Based on seasonal 
density data, Southern Resident killer whale occurrence is either not 
anticipated or is expected to be infrequent at Naval Sea Systems 
Command testing sites and in the locations where pierside maintenance 
and testing are designated to occur. Additionally, given the sheltered, 
calm waters, there is an increased likelihood that any Southern 
Resident killer whales or gray whales in these areas would be observed 
by Navy Lookouts, as described in Section 5.3.2.1 (Active Sonar) of the 
2020 NWTT FSEIS/OEIS.
    New mitigation in this mitigation area will reduce the types of 
active sonar activities and the active sonar source levels when 
practical, and therefore the overall amount of active sonar (i.e., 
number of hours) conducted in the mitigation area, and the overall 
potential for marine mammal exposure, while allowing the Navy to 
successfully accomplish events that require the use of active sonar in 
designated locations. Additionally, new mitigation will effectively 
reduce the locations, charge sizes, and overall annual number of 
explosive detonations in the mitigation area, which will avoid or 
reduce potential overlap of explosive activities within Southern 
Resident killer whale and gray whale habitat to the maximum extent 
practical. New mitigation will also help avoid any impacts from 
explosives and non-explosive practice munitions on marine mammals 
throughout NWTT Inland Waters.

Availability for Subsistence Uses

    The nature of subsistence activities by Alaskan Natives in the NWTT 
Study Area are discussed in detail below, in the Subsistence Harvest of 
Marine Mammals section of this final rule. As noted in that section, 
testing activities in the Western Behm Canal are the only activities 
within the NWTT Study Area that have the potential to affect 
subsistence uses of marine mammals. The Navy will notify the following 
Alaskan Native communities of the issuance of Notices to Mariners of 
Navy operations that involve restricting access in the Western Behm 
Canal at least 72 hours in advance: Central Council of the Tlingit and 
Haida Indian Tribes, Ketchikan Indian Corporation, Organized Village of 
Saxman, and Metlakatla Indian Community, Annette Island Reserve. These 
notifications will minimize potential impacts on subsistence hunters.

Mitigation Conclusions

    NMFS has carefully evaluated the mitigation measures--many of which 
were developed with NMFS' input during the previous phases of Navy 
training and testing authorizations but several of which are new since 
implementation of the 2015 to 2020 regulations or new since publication 
of the proposed rule (and addressing some of the information or 
recommendations received during the public comment period). NMFS has 
also considered a broad range of other measures (e.g., the measures 
considered but eliminated in the 2020 NWTT FSEIS/OEIS, which reflect 
other comments that have arisen via NMFS or public input in past years) 
in the context of ensuring that NMFS prescribes the means of effecting 
the least practicable adverse impact on the affected marine mammal 
species or stocks and their habitat and on the availability of the 
species or stocks for subsistence uses. Our evaluation of potential 
measures included consideration of the following factors in relation to 
one another: The manner in which, and the degree to which, the 
successful implementation of the mitigation measures is expected to 
reduce the likelihood and/or magnitude of adverse impacts to marine 
mammal species or stocks and their habitat; the manner in which, and 
the degree to which, the successful implementation of the mitigation 
measures is expected to reduce the likelihood and/or magnitude of 
adverse impacts on subsistence uses; the proven or likely efficacy of 
the measures; and the practicability of the measures for applicant 
implementation, including (for measures to address adverse impacts to 
marine mammal species or stocks and their habitat) consideration of 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.
    Based on our evaluation of the Navy's proposed measures, as well as 
other measures considered by the Navy and NMFS, NMFS has determined 
that the mitigation measures included in this final rule are the 
appropriate means of effecting the least practicable adverse impact on 
marine mammal species or stocks and their habitat, paying particular 
attention to rookeries, mating grounds, and areas of similar

[[Page 72420]]

significance, and considering specifically personnel safety, 
practicality of implementation, and impact on the effectiveness of the 
military readiness activity, and on the availability of the species and 
stocks for subsistence uses. Additionally, an adaptive management 
provision ensures that mitigation is regularly assessed and provides a 
mechanism to improve the mitigation, based on the factors above, 
through modification as appropriate. Thus, NMFS concludes that the 
mitigation measures outlined in this final rule satisfy the statutory 
standard and that any adverse impacts that remain cannot be practicably 
further mitigated.

Monitoring

    Section 101(a)(5)(A) of the MMPA states that in order to authorize 
incidental take for an activity, NMFS must set forth requirements 
pertaining to the monitoring and reporting of such taking. The MMPA 
implementing regulations at 50 CFR 216.104(a)(13) indicate that 
requests for incidental take authorizations must include the suggested 
means of accomplishing the necessary monitoring and reporting that will 
result in increased knowledge of the species and of the level of taking 
or impacts on populations of marine mammals that are expected to be 
present.
    Although the Navy has been conducting research and monitoring in 
the NWTT Study Area for over 20 years, it developed a formal marine 
species monitoring program in support of the MMPA and ESA 
authorizations in 2009. This robust program has resulted in hundreds of 
technical reports and publications on marine mammals that have informed 
Navy and NMFS analyses in environmental planning documents, MMPA rules, 
and ESA Biological Opinions. The reports are made available to the 
public on the Navy's marine species monitoring website 
(www.navymarinespeciesmonitoring.us) and the data on the Ocean 
Biogeographic Information System Spatial Ecological Analysis of 
Megavertebrate Populations (OBIS-SEAMAP) site (http://seamap.env.duke.edu/) and the Animal Telemetry Network (https://atn.ioos.us/).
    The Navy will continue collecting monitoring data to inform our 
understanding of the occurrence of marine mammals in the NWTT Study 
Area; the likely exposure of marine mammals to stressors of concern in 
the NWTT Study Area; the response of marine mammals to exposures to 
stressors; the consequences of a particular marine mammal response to 
their individual fitness and, ultimately, populations; and the 
effectiveness of implemented mitigation measures. Taken together, 
mitigation and monitoring comprise the Navy's integrated approach for 
reducing environmental impacts from the specified activities. The 
Navy's overall monitoring approach seeks to leverage and build on 
existing research efforts whenever possible.
    As agreed upon between the Navy and NMFS, the monitoring measures 
presented here, as well as the mitigation measures described above, 
focus on the protection and management of potentially affected marine 
mammals. A well-designed monitoring program can provide important 
feedback for validating assumptions made in analyses and allow for 
adaptive management of marine resources.

Integrated Comprehensive Monitoring Program (ICMP)

    The Navy's ICMP is intended to coordinate marine species monitoring 
efforts across all regions and to allocate the most appropriate level 
and type of effort for each range complex based on a set of 
standardized objectives, and in acknowledgement of regional expertise 
and resource availability. The ICMP is designed to be flexible, 
scalable, and adaptable through the adaptive management and strategic 
planning processes to periodically assess progress and reevaluate 
objectives. This process includes conducting an annual adaptive 
management review meeting, at which the Navy and NMFS jointly consider 
the prior-year goals, monitoring results, and related scientific 
advances to determine if monitoring plan modifications are warranted to 
more effectively address program goals. Although the ICMP does not 
specify actual monitoring field work or individual projects, it does 
establish a matrix of goals and objectives that have been developed in 
coordination with NMFS. As the ICMP is implemented through the 
Strategic Planning Process (see the section below), detailed and 
specific studies that support the Navy's and NMFS' top-level monitoring 
goals will continue to be developed. In essence, the ICMP directs that 
monitoring activities relating to the effects of Navy training and 
testing activities on marine species should be designed to contribute 
towards one or more of the following top-level goals:
     An increase in the understanding of the likely occurrence 
of marine mammals and/or ESA-listed marine species in the vicinity of 
the action (i.e., presence, abundance, distribution, and density of 
species);
     An increase in the understanding of the nature, scope, or 
context of the likely exposure of marine mammals and/or ESA-listed 
species to any of the potential stressors associated with the action 
(e.g., sound, explosive detonation, or military expended materials), 
through better understanding of one or more of the following: (1) The 
action and the environment in which it occurs (e.g., sound-source 
characterization, propagation, and ambient noise levels), (2) the 
affected species (e.g., life history or dive patterns), (3) the likely 
co-occurrence of marine mammals and/or ESA-listed marine species with 
the action (in whole or part), and (4) the likely biological or 
behavioral context of exposure to the stressor for the marine mammal 
and/or ESA-listed marine species (e.g., age class of exposed animals or 
known pupping, calving, or feeding areas);
     An increase in the understanding of how individual marine 
mammals or ESA-listed marine species respond (behaviorally or 
physiologically) to the specific stressors associated with the action 
(in specific contexts, where possible, e.g., at what distance or 
received level);
     An increase in the understanding of how anticipated 
individual responses, to individual stressors or anticipated 
combinations of stressors, may impact either (1) the long-term fitness 
and survival of an individual; or (2) the population, species, or stock 
(e.g., through impacts on annual rates of recruitment or survival);
     An increase in the understanding of the effectiveness of 
mitigation and monitoring measures;
     A better understanding and record of the manner in which 
the Navy complies with the incidental take regulations and LOAs and the 
ESA Incidental Take Statement;
     An increase in the probability of detecting marine mammals 
(through improved technology or methods), both specifically within the 
mitigation zones (thus allowing for more effective implementation of 
the mitigation) and in general, to better achieve the above goals; and
     Ensuring that adverse impact of activities remains at the 
least practicable level.

Strategic Planning Process for Marine Species Monitoring

    The Navy also developed the Strategic Planning Process for Marine 
Species Monitoring, which establishes the guidelines and processes 
necessary to

[[Page 72421]]

develop, evaluate, and fund individual projects based on objective 
scientific study questions. The process uses an underlying framework 
designed around intermediate scientific objectives and a conceptual 
framework incorporating a progression of knowledge spanning occurrence, 
exposure, response, and consequence. The Strategic Planning Process for 
Marine Species Monitoring is used to set overarching intermediate 
scientific objectives; develop individual monitoring project concepts; 
identify potential species of interest at a regional scale; evaluate, 
prioritize, and select specific monitoring projects to fund or continue 
supporting for a given fiscal year; execute and manage selected 
monitoring projects; and report and evaluate progress and results. This 
process addresses relative investments to different range complexes 
based on goals across all range complexes, and monitoring leverages 
multiple techniques for data acquisition and analysis whenever 
possible. The Strategic Planning Process for Marine Species Monitoring 
is also available online (http://www.navymarinespeciesmonitoring.us/).

Past and Current Monitoring in the NWTT Study Area

    The monitoring program has undergone significant changes since the 
first rule was issued for the NWTT Study Area in 2010, which highlights 
the monitoring program's evolution through the process of adaptive 
management. The monitoring program developed for the first cycle of 
environmental compliance documents (e.g., U.S. Department of the Navy, 
2008a, 2008b) utilized effort-based compliance metrics that were 
somewhat limiting. Through adaptive management discussions, the Navy 
designed and conducted monitoring studies according to scientific 
objectives, thereby eliminating basing requirements upon metrics of 
level-of-effort. Furthermore, refinements of scientific objectives have 
continued through the latest authorization cycle.
    Progress has also been made on the conceptual framework categories 
from the Scientific Advisory Group for Navy Marine Species Monitoring 
(U.S. Department of the Navy, 2011), ranging from occurrence of 
animals, to their exposure, response, and population consequences. The 
Navy continues to manage the Atlantic and Pacific program as a whole, 
with monitoring in each range complex taking a slightly different but 
complementary approach. The Navy has continued to use the approach of 
layering multiple simultaneous components in many of the range 
complexes to leverage an increase in return of the progress toward 
answering scientific monitoring questions. This includes in the NWTT 
Study Area, for example, (a) satellite tagging of blue whales, fin 
whales, humpback whales, and Southern Resident killer whales; (b) 
analysis of existing passive acoustic monitoring datasets; and (c) 
line-transect aerial surveys for marine mammals in Puget Sound, 
Washington.
    Numerous publications, dissertations, and conference presentations 
have resulted from research conducted under the marine species 
monitoring program (https://www.navymarinespeciesmonitoring.us/reading-room/publications/), resulting in a significant contribution to the 
body of marine mammal science. Publications on occurrence, 
distribution, and density have fed the modeling input, and publications 
on exposure and response have informed Navy and NMFS analysis of 
behavioral response and consideration of mitigation measures.
    Furthermore, collaboration between the monitoring program and the 
Navy's research and development (e.g., the Office of Naval Research) 
and demonstration-validation (e.g., Living Marine Resources) programs 
has been strengthened, leading to research tools and products that have 
already transitioned to the monitoring program. These include Marine 
Mammal Monitoring on Ranges (M3R), controlled exposure experiment 
behavioral response studies (CEE BRS), acoustic sea glider surveys, and 
global positioning system-enabled satellite tags. Recent progress has 
been made with better integration with monitoring across all Navy at-
sea study areas, including study areas in the Pacific and the Atlantic 
Oceans, and various other testing ranges. Publications from the Living 
Marine Resources and Office of Naval Research programs have also 
resulted in significant contributions to information on hearing ranges 
and acoustic criteria used in effects modeling, exposure, and response, 
as well as in developing tools to assess biological significance (e.g., 
population-level consequences).
    NMFS and the Navy also consider data collected during procedural 
mitigations as monitoring. Data are collected by shipboard personnel on 
hours spent training, hours of observation, hours of sonar, and marine 
mammals observed within the mitigation zones when mitigations are 
implemented. These data are provided to NMFS in both classified and 
unclassified annual exercise reports, which will continue under this 
rule.
    NMFS has received multiple years' worth of annual exercise and 
monitoring reports addressing active sonar use and explosive 
detonations within the NWTT Study Area and other Navy range complexes. 
The data and information contained in these reports have been 
considered in developing mitigation and monitoring measures for the 
training and testing activities within the NWTT Study Area. The Navy's 
annual exercise and monitoring reports may be viewed at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities and https://www.navymarinespeciesmonitoring.us/reporting/.
    The Navy's marine species monitoring program typically supports 
several monitoring projects in the NWTT Study Area at any given time. 
Additional details on the scientific objectives for each project can be 
found at https://www.navymarinespeciesmonitoring.us/regions/pacific/current-projects/. Projects can be either major multi-year efforts, or 
one to two-year special studies. The emphasis on species-specific 
monitoring in the Pacific Northwest is directed towards collecting and 
analyzing tagging data related to the occurrence of blue whales, fin 
whales, humpback whales, and Southern Resident killer whales. In 2017, 
researchers deployed 28 tags on blue whales and one tag on a fin whale 
(Mate et al., 2017, 2018a). Humpback whales have been tagged with 
satellite tags, and biopsy samples have been collected (Mate et al., 
2017, 2018b, 2019, 2020). Location information on Southern Resident 
killer whales was provided via satellite tag data and acoustic 
detections (Emmons et al., 2019; Hanson et al., 2018; Riera et al., 
2019). Also, distribution of Chinook salmon (a key prey species of 
Southern Resident killer whales) in coastal waters from Alaska to 
Northern California was studied (Shelton et al., 2018).
    Specific monitoring under the 2015-2020 regulations included the 
following projects:
     QRS Unmanned Acoustic Glider;
     PAM for Marine Mammals in the NWTRC;
     Modeling the Offshore Distribution of Southern Resident 
Killer Whales in the Pacific Northwest;
     Marine Mammal Density Surveys in the Pacific Northwest 
(Inland Puget Sound);
     Blue and Fin Whale Tagging and Genetics; Tagging and 
Behavioral Monitoring of Sea Lions in the Pacific Northwest in 
Proximity to Navy Facilities;

[[Page 72422]]

     Harbor Seal Density Estimation; Humpback Whale Tagging in 
Support of Marine Mammal Monitoring Across Multiple Navy Training Areas 
in the Pacific Ocean;
     Modeling the Offshore Distribution of Chinook Salmon in 
the Pacific Northwest;
     Characterizing the Distribution of ESA-Listed Salmonids in 
the Pacific Northwest;
     Guadalupe Fur Seal Satellite Tracking;
    Future monitoring efforts in the NWTT Study Area are anticipated to 
continue along the same objectives: determining the species and 
populations of marine mammals present and potentially exposed to Navy 
training and testing activities in the NWTT Study Area, through 
tagging, passive acoustic monitoring, refined modeling, photo 
identification, biopsies, and visual monitoring.
    Currently planned monitoring projects for the 2020-2027 rule are 
listed below. Monitoring projects are typically planned one year in 
advance; therefore, this list does not include all projects that will 
occur over the entire period of the rule.
     Offshore Distribution of Southern Resident Killer Whales 
in the Pacific Northwest (ongoing and planned through 2022)--Objectives 
include: (1) Identify and classify Southern Resident killer whale 
detections from acoustic recorders and satellite tag tracking; (2) 
Develop a model to estimate the seasonal and annual occurrence patterns 
of Southern Resident killer whales relative to offshore Navy training 
ranges; (3) Characterize occurrence of anthropogenic sounds in 
potential Southern Resident killer whale habitat; and (4) Develop state 
space habitat model for Southern Resident killer whale prey, based on 
fall Chinook salmon tagged and released from California to British 
Columbia between 1977 and 1990 to estimate seasonal distribution along 
the West Coast. Methods include: Passive acoustic monitoring, model 
development, visual survey, satellite tagging, and analysis of archived 
data.
     Characterizing the Distribution of ESA-Listed Salmonids in 
the Pacific Northwest (ongoing and planned through 2022)--Objectives 
include: To use a combination of acoustic and pop-up satellite tagging 
technology to provide critical information on spatial and temporal 
distribution of salmonids to inform salmon management, U.S. Navy 
training activities, and Southern Resident killer whale conservation. 
The study seeks to (1) determine the occurrence and timing of salmonids 
within the Navy training ranges; (2) describe the influence of 
environmental covariates on salmonid occurrence; and (3) describe the 
occurrence of salmonids in relation to Southern Resident killer whale 
distribution. Methods include: Acoustic telemetry (pinger tags) and 
pop-up satellite tagging.

Adaptive Management

    The regulations governing the take of marine mammals incidental to 
Navy training and testing activities in the NWTT Study Area contain an 
adaptive management component. Our understanding of the effects of Navy 
training and testing activities (e.g., acoustic and explosive 
stressors) on marine mammals continues to evolve, which makes the 
inclusion of an adaptive management component both valuable and 
necessary within the context of seven-year regulations.
    The reporting requirements associated with this rule are designed 
to provide NMFS with monitoring data from the previous year to allow 
NMFS to consider whether any changes to existing mitigation and 
monitoring requirements are appropriate. The use of adaptive management 
allows NMFS to consider new information from different sources to 
determine (with input from the Navy regarding practicability) on an 
annual or biennial basis if mitigation or monitoring measures should be 
modified (including additions or deletions). Mitigation measures could 
be modified if new data suggests that such modifications will have a 
reasonable likelihood of more effectively accomplishing the goals of 
the mitigation and monitoring and if the measures are practicable. If 
the modifications to the mitigation, monitoring, or reporting measures 
are substantial, NMFS will publish a notice of the planned LOAs in the 
Federal Register and solicit public comment.
    The following are some of the possible sources of applicable data 
to be considered through the adaptive management process: (1) Results 
from monitoring and exercise reports, as required by MMPA 
authorizations; (2) compiled results of Navy funded research and 
development studies; (3) results from specific stranding 
investigations; (4) results from general marine mammal and sound 
research; and (5) any information which reveals that marine mammals may 
have been taken in a manner, extent, or number not authorized by these 
regulations or subsequent LOAs. The results from monitoring reports and 
other studies may be viewed at https://www.navymarinespeciesmonitoring.us.

Reporting

    In order to issue incidental take authorization for an activity, 
section 101(a)(5)(A) of the MMPA states that NMFS must set forth 
requirements pertaining to the monitoring and reporting of such taking. 
Effective reporting is critical both to compliance as well as ensuring 
that the most value is obtained from the required monitoring. Reports 
from individual monitoring events, results of analyses, publications, 
and periodic progress reports for specific monitoring projects will be 
posted to the Navy's Marine Species Monitoring web portal: http://www.navymarinespeciesmonitoring.us.
    There were several different reporting requirements pursuant to the 
2015-2020 regulations. All of these reporting requirements will 
continue under this rule for the seven-year period.

Notification of Injured, Live Stranded, or Dead Marine Mammals

    The Navy will consult the Notification and Reporting Plan, which 
sets out notification, reporting, and other requirements when injured, 
live stranded, or dead marine mammals are detected. The Notification 
and Reporting Plan is available at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.

Annual NWTT Monitoring Report

    The Navy will submit an annual report to NMFS of the NWTT Study 
Area monitoring, which will be included in a Pacific-wide monitoring 
report including results specific to the NWTT Study Area, describing 
the implementation and results from the previous calendar year. Data 
collection methods will be standardized across Pacific Range Complexes 
including the MITT, HSTT, NWTT, and Gulf of Alaska (GOA) Study Areas to 
the best extent practicable, to allow for comparison in different 
geographic locations. The report must be submitted to the Director, 
Office of Protected Resources, NMFS, either within three months after 
the end of the calendar year, or within three months after the 
conclusion of the monitoring year, to be determined by the Adaptive 
Management process. NMFS will submit comments or questions on the draft 
monitoring report, if any, within three months of receipt. The report 
will be considered final after the Navy has addressed NMFS' comments, 
or three months after submittal of the draft if NMFS does not provide 
comments on the draft report. The report will describe progress of

[[Page 72423]]

knowledge made with respect to monitoring study questions across 
multiple Navy ranges associated with the ICMP. Similar study questions 
will be treated together so that progress on each topic is summarized 
across multiple Navy ranges. The report need not include analyses and 
content that does not provide direct assessment of cumulative progress 
on the monitoring plan study question. This will allow the Navy to 
provide a cohesive monitoring report covering multiple ranges (as per 
ICMP goals), rather than entirely separate reports for the MITT, HSTT, 
NWTT, and GOA Study Areas.

NWTT Annual Training Exercise Report and Annual Testing Activity Report

    Each year, the Navy will submit two preliminary reports (Quick Look 
Reports) to NMFS detailing the status of applicable sound sources 
within 21 days after the anniversary of the date of issuance of the 
LOAs. The Navy will also submit detailed reports (NWTT Annual Training 
Exercise and Annual Testing Activity Reports) to NMFS within three 
months after the one-year anniversary of the date of issuance of the 
LOAs. If desired, the Navy may elect to consolidate the NWTT Annual 
Training Exercise Report and the Annual Testing Activity Report with 
other exercise and activity reports from other range complexes in the 
Pacific Ocean for a single Pacific Training Exercise and Testing 
Activity Report. NMFS will submit comments or questions on the reports, 
if any, within one month of receipt. The reports will be considered 
final after the Navy has addressed NMFS' comments, or one month after 
submittal of the drafts if NMFS does not provide comments on the draft 
reports. The annual reports will contain a summary of all sound sources 
used (total hours or quantity of each bin of sonar or other non-
impulsive source; total annual number of each type of explosive; and 
total annual expended/detonated rounds (missiles, bombs, sonobuoys, 
etc.) for each explosive bin).
    Both reports will also contain both current year's sonar and 
explosive use data as well as cumulative sonar and explosive use 
quantity from previous years' reports. Additionally, if there were any 
changes to the sound source allowance in the reporting year, or 
cumulatively, the report will include a discussion of why the change 
was made and include analysis to support how the change did or did not 
affect the analysis in the 2020 NWTT FSEIS/OEIS and MMPA final rule. 
See the regulations below for more detail on the content of the annual 
report.
    Within the annual classified training exercise and testing activity 
reports, separate from the unclassified reports described above, the 
Navy will specifically include the following information:
     Total hours of authorized low-frequency, mid-frequency, 
and high-frequency active sonar (all bins, by bin) used during training 
and testing annually within the Olympic Coast National Marine 
Sanctuary; and
     Total hours of surface ship hull-mounted MF1 mid-frequency 
active sonar used in the following mitigation areas:
    1. Testing annually in three combined areas: 20 nmi from shore in 
the Marine Species Coastal Mitigation Area, the Juan de Fuca Eddy 
Marine Species Mitigation Area, and the Olympic Coast National Marine 
Sanctuary Mitigation Area.
    2. Training and testing from May 1 to November 30 within the 
Stonewall and Heceta Bank Humpback Whale Mitigation Area.
    3. Training and testing from July 1 to November 30 within the Point 
St. George Humpback Whale Mitigation Area.
    The final annual reports at the conclusion of the authorization 
period (year seven) will also serve as the comprehensive close-out 
report and include both the final year annual use compared to annual 
authorization as well as a cumulative seven-year annual use compared to 
seven-year authorization. NMFS must submit comments on the draft close-
out report, if any, within three months of receipt. The report will be 
considered final after the Navy has addressed NMFS' comments, or three 
months after the submittal of the draft if NMFS does not provide 
comments.
    Information included in the annual reports may be used to inform 
future adaptive management of activities within the NWTT Study Area.

Other Reporting and Coordination

    The Navy will continue to report and coordinate with NMFS for the 
following:
     Annual marine species monitoring technical review meetings 
(in-person or remote, as circumstances allow and agreed upon by NMFS 
and the Navy) that also include researchers and the Marine Mammal 
Commission (currently, every two years a joint Pacific-Atlantic meeting 
is held); and
     Annual Adaptive Management meetings (in-person or remote, 
as circumstances allow and agreed upon by NMFS and the Navy) that also 
include the Marine Mammal Commission (recently modified to occur in 
conjunction with the annual monitoring technical review meeting).

Analysis and Negligible Impact Determination

General Negligible Impact Analysis

Introduction
    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In considering 
how Level A harassment or Level B harassment (as presented in Tables 32 
and 33), factor into the negligible impact analysis, in addition to 
considering the number of estimated takes, NMFS considers other 
factors, such as the likely nature of any responses (e.g., intensity, 
duration) and the context of any responses (e.g., critical reproductive 
time or location, migration), as well as effects on habitat and the 
likely effectiveness of the mitigation. We also assess the number, 
intensity, and context of estimated takes by evaluating this 
information relative to population status. Consistent with the 1989 
preamble for NMFS' implementing regulations (54 FR 40338; September 29, 
1989), the impacts from other past and ongoing anthropogenic activities 
are incorporated into this analysis via their impacts on the 
environmental baseline (e.g., as reflected in the regulatory status of 
the species, population size, and growth rate where known).
    In the Estimated Take of Marine Mammals section, we identified the 
subset of potential effects that are expected to rise to the level of 
takes both annually and over the seven-year period covered by this 
rule, and then identified the maximum number of takes we believe could 
occur (mortality) or are reasonably expected to occur (harassment) 
based on the methods described. The impact that any given take will 
have on an individual, and ultimately the species or stock, is 
dependent on many case-specific factors that need to be considered in 
the negligible impact analysis (e.g., the context of behavioral 
exposures such as duration or intensity of a disturbance, the health of 
impacted animals, the status of a species that incurs fitness-

[[Page 72424]]

level impacts to individuals, etc.). For this rule we evaluated the 
likely impacts of the enumerated maximum number of harassment takes 
that are reasonably expected to occur, and are authorized, in the 
context of the specific circumstances surrounding these predicted 
takes. We also specifically assessed serious injury or mortality 
(hereafter referred to as M/SI) takes that could occur, as well as 
considering the traits and statuses of the affected species and stocks. 
Last, we collectively evaluated this information, as well as other more 
taxa-specific information and mitigation measure effectiveness, in 
group-specific assessments that support our negligible impact 
conclusions for each stock or species. Because all of the Navy's 
specified activities will occur within the ranges of the marine mammal 
stocks identified in the rule, all negligible impact analyses and 
determinations are at the stock level (i.e., additional species-level 
determinations are not needed).
    The specified activities reflect representative levels of training 
and testing activities. The Description of the Specified Activities 
section describes annual activities. There may be some flexibility in 
the exact number of hours, items, or detonations that may vary from 
year to year, but take totals will not exceed the maximum annual totals 
and seven-year totals indicated in Tables 32 and 33. We base our 
analysis and negligible impact determination on the maximum number of 
takes that are reasonably expected to occur and are authorized, 
although, as stated before, the number of takes are only a part of the 
analysis, which includes extensive qualitative consideration of other 
contextual factors that influence the degree of impact of the takes on 
the affected individuals. To avoid repetition, we provide some general 
analysis in this General Negligible Impact Analysis section that 
applies to all the species listed in Tables 32 and 33, given that some 
of the anticipated effects of the Navy's training and testing 
activities on marine mammals are expected to be relatively similar in 
nature. Then, in the Group and Species-Specific Analyses section, we 
subdivide into discussions of Mysticetes, Odontocetes, and pinnipeds, 
as there are broad life history traits that support an overarching 
discussion of some factors considered within the analysis for those 
groups (e.g., high-level differences in feeding strategies). Last, we 
break our analysis into species (and/or stocks), or groups of species 
(and the associated stocks) where relevant similarities exist, to 
provide more specific information related to the anticipated effects on 
individuals of a specific stock or where there is information about the 
status or structure of any species or stock that would lead to a 
differing assessment of the effects on the species or stock. Organizing 
our analysis by grouping species or stocks that share common traits or 
that will respond similarly to effects of the Navy's activities and 
then providing species- or stock-specific information allows us to 
avoid duplication while assuring that we have analyzed the effects of 
the specified activities on each affected species or stock.
Harassment
    The Navy's harassment take request is based on a model that 
includes a quantitative assessment of procedural mitigation, which NMFS 
reviewed and concurs appropriately predicts the maximum amount of 
harassment that is likely to occur. The model calculates sound energy 
propagation from sonar, other active acoustic sources, and explosives 
during naval activities; the sound or impulse received by animat 
dosimeters representing marine mammals distributed in the area around 
the modeled activity; and whether the sound or impulse energy received 
by a marine mammal exceeds the thresholds for effects. Assumptions in 
the Navy model intentionally err on the side of overestimation when 
there are unknowns. Naval activities are modeled as though they would 
occur regardless of proximity to marine mammals, meaning that no 
mitigation is considered (e.g., no power down or shut down) and without 
any avoidance of the activity by the animal. The final step of the 
quantitative analysis of acoustic effects, which occurs after the 
modeling, is to consider the implementation of mitigation and the 
possibility that marine mammals would avoid continued or repeated sound 
exposures. NMFS provided input to, independently reviewed, and 
concurred with the Navy on this process and the Navy's analysis, which 
is described in detail in Section 6 of the Navy's rulemaking/LOA 
application, was used to quantify harassment takes for this rule.
    Generally speaking, the Navy and NMFS anticipate more severe 
effects from takes resulting from exposure to higher received levels 
(though this is in no way a strictly linear relationship for behavioral 
effects throughout species, individuals, or circumstances) and less 
severe effects from takes resulting from exposure to lower received 
levels. However, there is also growing evidence of the importance of 
distance in predicting marine mammal behavioral response to sound--
i.e., sounds of a similar level emanating from a more distant source 
have been shown to be less likely to evoke a response of equal 
magnitude (DeRuiter 2012, Falcone et al., 2017). The estimated number 
of takes by Level A harassment and Level B harassment does not equate 
to the number of individual animals the Navy expects to harass (which 
is lower), but rather to the instances of take (i.e., exposures above 
the Level A harassment and Level B harassment threshold) that are 
anticipated to occur annually and over the seven-year period. These 
instances may represent either brief exposures (seconds or minutes) or, 
in some cases, longer durations of exposure within a day. Some 
individuals may experience multiple instances of take (i.e., on 
multiple days) over the course of a year, which means that the number 
of individuals taken is smaller than the total estimated takes. 
Generally speaking, the higher the number of takes as compared to the 
population abundance, the more repeated takes of individuals are 
likely, and the higher the actual percentage of individuals in the 
population that are likely taken at least once in a year. We look at 
this comparative metric to give us a relative sense of where a larger 
portion of a species or stock is being taken by Navy activities, where 
there is a higher likelihood that the same individuals are being taken 
on multiple days, and where that number of days might be higher or more 
likely sequential. Where the number of instances of take is 100 percent 
or less of the abundance and there is no information to specifically 
suggest that a small subset of animals will be repeatedly taken over a 
high number of sequential days, the overall magnitude is generally 
considered low, as it could on one extreme mean that every individual 
taken will be taken on no more than one day annually (a very minimal 
impact) or, more likely, that some smaller portion of individuals are 
taken on one day annually, some are taken on a few not likely 
sequential days annually, and some are not taken at all.
    In the ocean, the Navy's use of sonar and other active acoustic 
sources is often transient and is unlikely to repeatedly expose the 
same individual animals within a short period, for example within one 
specific exercise. However, for some individuals of some species or 
stocks repeated exposures across different activities could occur over 
the year, especially where events occur in generally the same area with 
more resident species (e.g., pinnipeds in

[[Page 72425]]

inland waters). In short, for some species or stocks we expect that the 
total anticipated takes represent exposures of a smaller number of 
individuals of which some will be exposed multiple times, but based on 
the nature of the Navy activities and the movement patterns of marine 
mammals, it is unlikely that individuals from most stocks (with the 
exception of one stock of harbor seals) will be taken over more than a 
few non-sequential days and, as described elsewhere, the nature of the 
majority of the exposures is expected to be of a less severe nature.
Physiological Stress Response
    Some of the lower level physiological stress responses (e.g., 
orientation or startle response, change in respiration, change in heart 
rate) discussed in the proposed rule would likely co-occur with the 
predicted harassments, although these responses are more difficult to 
detect and fewer data exist relating these responses to specific 
received levels of sound. Takes by Level B harassment, then, may have a 
stress-related physiological component as well; however, we would not 
expect the Navy's generally short-term, intermittent, and (typically in 
the case of sonar) transitory activities to create conditions of long-
term continuous noise leading to long-term physiological stress 
responses in marine mammals that could affect reproduction or survival.
Behavioral Response
    The estimates calculated using the BRF do not differentiate between 
the different types of behavioral responses that rise to the level of 
take by Level B harassment. As described in the Navy's application, the 
Navy identified (with NMFS' input) the types of behaviors that would be 
considered a take: Moderate behavioral responses as characterized in 
Southall et al. (2007) (e.g., altered migration paths or dive profiles; 
interrupted nursing, breeding, or feeding; or avoidance) that also 
would be expected to continue for the duration of an exposure. The Navy 
then compiled the available data indicating at what received levels and 
distances those responses have occurred, and used the indicated 
literature to build biphasic behavioral response curves and cutoff 
distances that are used to predict how many instances of Level B 
harassment by behavioral disturbance occur in a day. Take estimates 
alone do not provide information regarding the potential fitness or 
other biological consequences of the reactions on the affected 
individuals. We therefore consider the available activity-specific, 
environmental, and species-specific information to determine the likely 
nature of the modeled behavioral responses and the potential fitness 
consequences for affected individuals.
    Use of sonar and other transducers would typically be transient and 
temporary. The majority of acoustic effects to individual animals from 
sonar and other active sound sources during training and testing 
activities would be primarily from ASW events. Unlike other Navy 
training and testing Study Areas, no major training exercises (MTEs) 
are planned in the NWTT Study Area. In the range of potential 
behavioral effects that might expect to be part of a response that 
qualifies as an instance of Level B harassment by behavioral 
disturbance (which by nature of the way it is modeled/counted, occurs 
within one day), the less severe end might include exposure to 
comparatively lower levels of a sound, at a detectably greater distance 
from the animal, for a few or several minutes. A less severe exposure 
of this nature could result in a behavioral response such as avoiding 
an area that an animal would otherwise have chosen to move through or 
feed in for some amount of time or breaking off one or a few feeding 
bouts. More severe effects could occur if an animal gets close enough 
to the source to receive a comparatively higher level, is exposed 
continuously to one source for a longer time, or is exposed 
intermittently to different sources throughout a day. Such effects 
might result in an animal having a more severe flight response and 
leaving a larger area for a day or more or potentially losing feeding 
opportunities for a day. However, such severe behavioral effects are 
expected to occur infrequently.
    To help assess this, for sonar (LFAS/MFAS/HFAS) used in the NWTT 
Study Area, the Navy provided information estimating the percentage of 
animals that may be taken by Level B harassment under each BRF that 
would occur within 6-dB increments (percentages discussed below in the 
Group and Species-Specific Analyses section). As mentioned above, all 
else being equal, an animal's exposure to a higher received level is 
more likely to result in a behavioral response that is more likely to 
lead to adverse effects, which could more likely accumulate to impacts 
on reproductive success or survivorship of the animal, but other 
contextual factors (such as distance) are also important. The majority 
of takes by Level B harassment are expected to be in the form of milder 
responses (i.e., lower-level exposures that still rise to the level of 
take, but would likely be less severe in the range of responses that 
qualify as take) of a generally shorter duration. We anticipate more 
severe effects from takes when animals are exposed to higher received 
levels of sound or at closer proximity to the source. However, 
depending on the context of an exposure (e.g., depth, distance, if an 
animal is engaged in important behavior such as feeding), a behavioral 
response can vary between species and individuals within a species. 
Specifically, given a range of behavioral responses that may be 
classified as Level B harassment, to the degree that higher received 
levels are expected to result in more severe behavioral responses, only 
a smaller percentage of the anticipated Level B harassment from Navy 
activities might necessarily be expected to potentially result in more 
severe responses (see the Group and Species-Specific Analyses section 
below for more detailed information). To fully understand the likely 
impacts of the predicted/authorized take on an individual (i.e., what 
is the likelihood or degree of fitness impacts), one must look closely 
at the available contextual information, such as the duration of likely 
exposures and the likely severity of the exposures (e.g., whether they 
will occur for a longer duration over sequential days or the 
comparative sound level that will be received). Ellison et al. (2012) 
and Moore and Barlow (2013), among others, emphasize the importance of 
context (e.g., behavioral state of the animals, distance from the sound 
source.) in evaluating behavioral responses of marine mammals to 
acoustic sources.
Diel Cycle
    Many animals perform vital functions, such as feeding, resting, 
traveling, and socializing on a diel cycle (24-hour cycle). Behavioral 
reactions to noise exposure, when taking place in a biologically 
important context, such as disruption of critical life functions, 
displacement, or avoidance of important habitat, are more likely to be 
significant if they last more than one day or recur on subsequent days 
(Southall et al., 2007) due to diel and lunar patterns in diving and 
foraging behaviors observed in many cetaceans, including beaked whales 
(Baird et al. 2008, Barlow et al. 2020, Henderson et al. 2016, Schorr 
et al. 2014). Henderson et al. (2016) found that ongoing smaller scale 
events had little to no impact on foraging dives for Blainville's 
beaked whale, while multi-day training events may decrease foraging 
behavior for Blainville's beaked whale (Manzano-Roth et al., 2016). 
Consequently, a behavioral response lasting less than one day and not 
recurring on subsequent days is not

[[Page 72426]]

considered severe unless it could directly affect reproduction or 
survival (Southall et al., 2007). Note that there is a difference 
between multiple-day substantive behavioral reactions and multiple-day 
anthropogenic activities. For example, just because an at-sea exercise 
lasts for multiple days does not necessarily mean that individual 
animals are either exposed to those exercises for multiple days or, 
further, exposed in a manner resulting in a sustained multiple day 
substantive behavioral response. Large multi-day Navy exercises such as 
ASW activities, typically include vessels that are continuously moving 
at speeds typically 10-15 kn, or higher, and likely cover large areas 
that are relatively far from shore (typically more than 3 nmi from 
shore) and in waters greater than 600 ft deep. Additionally marine 
mammals are moving as well, which would make it unlikely that the same 
animal could remain in the immediate vicinity of the ship for the 
entire duration of the exercise. Further, the Navy does not necessarily 
operate active sonar the entire time during an exercise. While it is 
certainly possible that these sorts of exercises could overlap with 
individual marine mammals multiple days in a row at levels above those 
anticipated to result in a take, because of the factors mentioned 
above, it is considered unlikely for the majority of takes. However, it 
is also worth noting that the Navy conducts many different types of 
noise-producing activities over the course of the year and it is likely 
that some marine mammals will be exposed to more than one and taken on 
multiple days, even if they are not sequential.
    Durations of Navy activities utilizing tactical sonar sources and 
explosives vary and are fully described in Appendix A (Navy Activity 
Descriptions) of the 2020 NWTT FSEIS/OEIS. Sonar used during ASW would 
impart the greatest amount of acoustic energy of any category of sonar 
and other transducers analyzed in the Navy's rulemaking/LOA application 
and include hull-mounted, towed, line array, sonobuoy, helicopter 
dipping, and torpedo sonars. Most ASW sonars are MFAS (1-10 kHz); 
however, some sources may use higher or lower frequencies. ASW training 
activities using hull mounted sonar planned for the NWTT Study Area 
generally last for only a few hours (see Table 3). Some ASW training 
and testing activities range from several hours, to days, to up to 3 
weeks for Pierside-Sonar Testing and Submarine Sonar Testing/
Maintenance (see Table 4). For these multi-day exercises there will 
typically be extended intervals of non-activity in between active sonar 
periods. Because of the need to train in a large variety of situations, 
the Navy does not typically conduct successive ASW exercises in the 
same locations. Given the average length of ASW exercises (times of 
sonar use) and typical vessel speed, combined with the fact that the 
majority of the cetaceans would not likely remain in proximity to the 
sound source, it is unlikely that an animal would be exposed to LFAS/
MFAS/HFAS at levels or durations likely to result in a substantive 
response that would then be carried on for more than one day or on 
successive days.
    Most planned explosive events are scheduled to occur over a short 
duration (1-8 hours); however Mine Countermeasure and Neutralization 
Testing would last 1-10 days (see Tables 3 and 4). The explosive 
component of these activities only lasts for minutes. Although 
explosive exercises may sometimes be conducted in the same general 
areas repeatedly, because of their short duration and the fact that 
they are in the open ocean and animals can easily move away, it is 
similarly unlikely that animals would be exposed for long, continuous 
amounts of time, or demonstrate sustained behavioral responses. All of 
these factors make it unlikely that individuals would be exposed to the 
exercise for extended periods or on consecutive days.
Assessing the Number of Individuals Taken and the Likelihood of 
Repeated Takes
    As described previously, Navy modeling uses the best available 
science to predict the instances of exposure above certain acoustic 
thresholds, which are equated, as appropriate, to harassment takes 
(and, for PTS, further corrected to account for mitigation and 
avoidance). As further noted, for active acoustics it is more 
challenging to parse out the number of individuals taken by Level B 
harassment and the number of times those individuals are taken from 
this larger number of instances. One method that NMFS uses to help 
better understand the overall scope of the impacts is to compare these 
total instances of take against the abundance of that species (or stock 
if applicable). For example, if there are 100 estimated harassment 
takes in a population of 100, one can assume either that every 
individual will be exposed above acoustic thresholds in no more than 
one day, or that some smaller number will be exposed in one day but a 
few of those individuals will be exposed multiple days within a year 
and a few not exposed at all. Where the instances of take exceed 100 
percent of the population (i.e., are over 100 percent), multiple takes 
of some individuals are predicted and expected to occur within a year. 
Generally speaking, the higher the number of takes as compared to the 
population abundance, the more multiple takes of individuals are 
likely, and the higher the actual percentage of individuals in the 
population that are likely taken at least once in a year. We look at 
this comparative metric to give us a relative sense of where a larger 
portion of a species or stock is being taken by Navy activities and 
where there is a higher likelihood that the same individuals are being 
taken across multiple days and where that number of days might be 
higher. It also provides a relative picture of the scale of impacts to 
each species.
    In the ocean, unlike a modeling simulation with static animals, the 
use of sonar and other active acoustic sources is often transient, and 
is unlikely to repeatedly expose the same individual animals within a 
short period, for example within one specific exercise. However, some 
repeated exposures across different activities could occur over the 
year with more resident species (e.g., pinnipeds in inland waters). In 
short, we expect that the total anticipated takes represent exposures 
of a smaller number of individuals of which some could be exposed 
multiple times, but based on the nature of the Navy's activities and 
the movement patterns of marine mammals, it is unlikely that any 
particular subset would be taken over more than a few non-sequential 
days (with the exception of three harbor seal stocks discussed in the 
species-specific analyses).
    When comparing the number of takes to the population abundance, 
which can be helpful in estimating both the proportion of the 
population affected by takes and the number of days over which some 
individuals may be taken, it is important to choose an appropriate 
population estimate against which to make the comparison. The SARs, 
where available, provide the official population estimate for a given 
species or stock in U.S. waters in a given year (and are typically 
based solely on the most recent survey data). When the stock is known 
to range well outside of U.S. EEZ boundaries, population estimates 
based on surveys conducted only within the U.S. EEZ are known to be 
underestimates. The information used to estimate take includes the best 
available survey abundance data to model density layers. Accordingly, 
in calculating the percentage of takes

[[Page 72427]]

versus abundance for each species or stock in order to assist in 
understanding both the percentage of the species or stock affected, as 
well as how many days across a year individuals could be taken, we use 
the data most appropriate for the situation. For all species and stocks 
except for a few stocks of harbor seals for which SAR data are 
unavailable and Navy abundance surveys of the inland areas of the NWTT 
Study Area are used, the most recent NMFS SARs are used to calculate 
the proportion of a population affected by takes.
    The stock abundance estimates in NMFS' SARs are typically generated 
from the most recent shipboard and/or aerial surveys conducted. In some 
cases, NMFS' abundance estimates show substantial year-to-year 
variability. However, for highly migratory species (e.g., large whales) 
or those whose geographic distribution extends well beyond the 
boundaries of the NWTT Study Area (e.g., populations with distribution 
along the entire eastern Pacific Ocean rather than just the NWTT Study 
Area), comparisons to the SAR are appropriate. Many of the stocks 
present in the NWTT Study Area have ranges significantly larger than 
the NWTT Study Area and that abundance is captured by the SAR. A good 
descriptive example is migrating large whales, which traverse the NWTT 
Study Area for several days to weeks on their migrations. Therefore, at 
any one time there may be a stable number of animals, but over the 
course of the entire year the entire population may pass through the 
NWTT Study Area. Therefore, comparing the estimated takes to an 
abundance, in this case the SAR abundance, which represents the total 
population, may be more appropriate than modeled abundances for only 
the NWTT Study Area.
Temporary Threshold Shift
    NMFS and the Navy have estimated that multiple species and stocks 
of marine mammals may sustain some level of TTS from active sonar. As 
discussed in the proposed rule in the Potential Effects of Specified 
Activities on Marine Mammals and their Habitat section, in general, TTS 
can last from a few minutes to days, be of varying degree, and occur 
across various frequency bandwidths, all of which determine the 
severity of the impacts on the affected individual, which can range 
from minor to more severe. Tables 52-57 indicate the number of takes by 
TTS that may be incurred by different species and stocks from exposure 
to active sonar and explosives. The TTS sustained by an animal is 
primarily classified by three characteristics:
    1. Frequency--Available data (of mid-frequency hearing specialists 
exposed to mid- or high-frequency sounds; Southall et al., 2007) 
suggest that most TTS occurs in the frequency range of the source up to 
one octave higher than the source (with the maximum TTS at \1/2\ octave 
above). The Navy's MF sources, which are the highest power and most 
numerous sources and the ones that cause the most take, utilize the 1-
10 kHz frequency band, which suggests that if TTS were to be induced by 
any of these MF sources it would be in a frequency band somewhere 
between approximately 2 and 20 kHz, which is in the range of 
communication calls for many odontocetes, but below the range of the 
echolocation signals used for foraging. There are fewer hours of HF 
source use and the sounds would attenuate more quickly, plus they have 
lower source levels, but if an animal were to incur TTS from these 
sources, it would cover a higher frequency range (sources are between 
10 and 100 kHz, which means that TTS could range up to 200 kHz), which 
could overlap with the range in which some odontocetes communicate or 
echolocate. However, HF systems are typically used less frequently and 
for shorter time periods than surface ship and aircraft MF systems, so 
TTS from these sources is unlikely. There are fewer LF sources and the 
majority are used in the more readily mitigated testing environment, 
and TTS from LF sources would most likely occur below 2 kHz, which is 
in the range where many mysticetes communicate and also where other 
non-communication auditory cues are located (waves, snapping shrimp, 
fish prey). Also of note, the majority of sonar sources from which TTS 
may be incurred occupy a narrow frequency band, which means that the 
TTS incurred would also be across a narrower band (i.e., not affecting 
the majority of an animal's hearing range). This frequency provides 
information about the cues to which a marine mammal may be temporarily 
less sensitive, but not the degree or duration of sensitivity loss. TTS 
from explosives would be broadband.
    2. Degree of the shift (i.e., by how many dB the sensitivity of the 
hearing is reduced)--Generally, both the degree of TTS and the duration 
of TTS will be greater if the marine mammal is exposed to a higher 
level of energy (which would occur when the peak dB level is higher or 
the duration is longer). The threshold for the onset of TTS was 
discussed previously in this rule. An animal would have to approach 
closer to the source or remain in the vicinity of the sound source 
appreciably longer to increase the received SEL, which would be 
difficult considering the Lookouts and the nominal speed of an active 
sonar vessel (10-15 kn) and the relative motion between the sonar 
vessel and the animal. In the TTS studies discussed in the Potential 
Effects of Specified Activities on Marine Mammals and their Habitat 
section of the proposed rule, some using exposures of almost an hour in 
duration or up to 217 SEL, most of the TTS induced was 15 dB or less, 
though Finneran et al. (2007) induced 43 dB of TTS with a 64-second 
exposure to a 20 kHz source. However, since any hull-mounted sonar, 
such as the SQS-53, engaged in anti-submarine warfare training would be 
moving at between 10 and 15 knots and nominally pinging every 50 
seconds, the vessel will have traveled a minimum distance of 
approximately 257 m during the time between those pings, and, 
therefore, incurring those levels of TTS is highly unlikely. A scenario 
could occur where an animal does not leave the vicinity of a ship or 
travels a course parallel to the ship, however, the close distances 
required make TTS exposure unlikely. For a Navy vessel moving at a 
nominal 10 knots, it is unlikely a marine mammal could maintain speed 
parallel to the ship and receive adequate energy over successive pings 
to suffer TTS.
    In short, given the anticipated duration and levels of sound 
exposure, we would not expect marine mammals to incur more than 
relatively low levels of TTS (i.e., single digits of sensitivity loss). 
To add context to this degree of TTS, individual marine mammals may 
regularly experience variations of 6 dB differences in hearing 
sensitivity across time (Finneran et al., 2000, 2002; Schlundt et al., 
2000).
    3. Duration of TTS (recovery time)--In the TTS laboratory studies 
(as discussed in the Potential Effects of Specified Activities on 
Marine Mammals and their Habitat section of the proposed rule), some 
using exposures of almost an hour in duration or up to 217 SEL, almost 
all individuals recovered within 1 day (or less, often in minutes), 
although in one study (Finneran et al., 2007), recovery took 4 days.
    Based on the range of degree and duration of TTS reportedly induced 
by exposures to non-pulse sounds of energy higher than that to which 
free-swimming marine mammals in the field are likely to be exposed 
during LFAS/MFAS/HFAS training and testing exercises in the NWTT Study 
Area, it is unlikely that marine mammals would ever sustain a TTS from 
MFAS that

[[Page 72428]]

alters their sensitivity by more than 20 dB for more than a few hours--
and any incident of TTS would likely be far less severe due to the 
short duration of the majority of the events and the speed of a typical 
vessel, especially given the fact that the higher power sources 
resulting in TTS are predominantly intermittent, which have been shown 
to result in shorter durations of TTS. Also, for the same reasons 
discussed in the Analysis and Negligible Impact Determination--Diel 
Cycle section, and because of the short distance within which animals 
would need to approach the sound source, it is unlikely that animals 
would be exposed to the levels necessary to induce TTS in subsequent 
time periods such that their recovery is impeded. Additionally, though 
the frequency range of TTS that marine mammals might sustain would 
overlap with some of the frequency ranges of their vocalization types, 
the frequency range of TTS from MFAS would not usually span the entire 
frequency range of one vocalization type, much less span all types of 
vocalizations or other critical auditory cues for any given species.
    Tables 52-57 indicate the maximum number of incidental takes by TTS 
for each species or stock that are likely to result from the Navy's 
activities. As a general point, the majority of these TTS takes are the 
result of exposure to hull-mounted MFAS (MF narrower band sources), 
with fewer from explosives (broad-band lower frequency sources), and 
even fewer from LFAS or HFAS sources (narrower band). As described 
above, we expect the majority of these takes to be in the form of mild 
(single-digit), short-term (minutes to hours), narrower band (only 
affecting a portion of the animal's hearing range) TTS. This means that 
for one to several times per year, for several minutes to maybe a few 
hours (high end) each, a taken individual will have slightly diminished 
hearing sensitivity (slightly more than natural variation, but nowhere 
near total deafness). More often than not, such an exposure would occur 
within a narrower mid- to higher frequency band that may overlap part 
(but not all) of a communication, echolocation, or predator range, but 
sometimes across a lower or broader bandwidth. The significance of TTS 
is also related to the auditory cues that are germane within the time 
period that the animal incurs the TTS. For example, if an odontocete 
has TTS at echolocation frequencies, but incurs it at night when it is 
resting and not feeding, it is not impactful. In short, the expected 
results of any one of these small number of mild TTS occurrences could 
be that (1) it does not overlap signals that are pertinent to that 
animal in the given time period, (2) it overlaps parts of signals that 
are important to the animal, but not in a manner that impairs 
interpretation, or (3) it reduces detectability of an important signal 
to a small degree for a short amount of time--in which case the animal 
may be aware and be able to compensate (but there may be slight 
energetic cost), or the animal may have some reduced opportunities 
(e.g., to detect prey) or reduced capabilities to react with maximum 
effectiveness (e.g., to detect a predator or navigate optimally). 
However, given the small number of times that any individual might 
incur TTS, the low degree of TTS and the short anticipated duration, 
and the low likelihood that one of these instances would occur in a 
time period in which the specific TTS overlapped the entirety of a 
critical signal, it is unlikely that TTS of the nature expected to 
result from the Navy activities would result in behavioral changes or 
other impacts that would impact any individual's (of any hearing 
sensitivity) reproduction or survival.
Auditory Masking or Communication Impairment
    The ultimate potential impacts of masking on an individual (if it 
were to occur) are similar to those discussed for TTS, but an important 
difference is that masking only occurs during the time of the signal, 
versus TTS, which continues beyond the duration of the signal. 
Fundamentally, masking is referred to as a chronic effect because one 
of the key potential harmful components of masking is its duration--the 
fact that an animal would have reduced ability to hear or interpret 
critical cues becomes much more likely to cause a problem the longer it 
is occurring. Also inherent in the concept of masking is the fact that 
the potential for the effect is only present during the times that the 
animal and the source are in close enough proximity for the effect to 
occur (and further, this time period would need to coincide with a time 
that the animal was utilizing sounds at the masked frequency). As our 
analysis has indicated, because of the relative movement of vessels and 
the sound sources primarily involved in this rule, we do not expect the 
exposures with the potential for masking to be of a long duration. 
Masking is fundamentally more of a concern at lower frequencies, 
because low frequency signals propagate significantly further than 
higher frequencies and because they are more likely to overlap both the 
narrower LF calls of mysticetes, as well as many non-communication cues 
such as fish and invertebrate prey, and geologic sounds that inform 
navigation. Masking is also more of a concern from continuous sources 
(versus intermittent sonar signals) where there is no quiet time 
between pulses within which auditory signals can be detected and 
interpreted. For these reasons, dense aggregations of, and long 
exposure to, continuous LF activity are much more of a concern for 
masking, whereas comparatively short-term exposure to the predominantly 
intermittent pulses of often narrow frequency range MFAS or HFAS, or 
explosions are not expected to result in a meaningful amount of 
masking. While the Navy occasionally uses LF and more continuous 
sources, it is not in the contemporaneous aggregate amounts that would 
accrue to a masking concern. Specifically, the nature of the activities 
and sound sources used by the Navy do not support the likelihood of a 
level of masking accruing that would have the potential to affect 
reproductive success or survival. Additional detail is provided below.
    Standard hull-mounted MFAS typically pings every 50 seconds. Some 
hull-mounted anti-submarine sonars can also be used in an object 
detection mode known as ``Kingfisher'' mode (e.g., used on vessels when 
transiting to and from port) where pulse length is shorter but pings 
are much closer together in both time and space since the vessel goes 
slower when operating in this mode. Kingfisher mode is typically 
operated for relatively shorter durations. For the majority of other 
sources, the pulse length is significantly shorter than hull-mounted 
active sonar, on the order of several microseconds to tens of 
milliseconds. Some of the vocalizations that many marine mammals make 
are less than one second long, so, for example with hull-mounted sonar, 
there would be a 1 in 50 chance (and only if the source was in close 
enough proximity for the sound to exceed the signal that is being 
detected) that a single vocalization might be masked by a ping. 
However, when vocalizations (or series of vocalizations) are longer 
than the one-second pulse of hull-mounted sonar, or when the pulses are 
only several microseconds long, the majority of most animals' 
vocalizations would not be masked.
    Most ASW sonars and countermeasures use MF frequencies and a few 
use LF and HF frequencies. Most of these sonar signals are limited in 
the temporal, frequency, and spatial domains. The duration of most 
individual sounds is short, lasting up to a few seconds each. A few 
systems operate with higher duty cycles or nearly continuously, but 
they typically

[[Page 72429]]

use lower power, which means that an animal would have to be closer, or 
in the vicinity for a longer time, to be masked to the same degree as 
by a higher level source. Nevertheless, masking could occasionally 
occur at closer ranges to these high-duty cycle and continuous active 
sonar systems, but as described previously, it would be expected to be 
of a short duration when the source and animal are in close proximity. 
While data are limited on behavioral responses of marine mammals to 
continuously active sonars, mysticete species are known to be able to 
habituate to novel and continuous sounds (Nowacek et al., 2004), 
suggesting that they are likely to have similar responses to high-duty 
cycle sonars. Furthermore, most of these systems are hull-mounted on 
surface ships and ships are moving at least 10 kn, and it is unlikely 
that the ship and the marine mammal would continue to move in the same 
direction with the marine mammal subjected to the same exposure due to 
that movement. Most ASW activities are geographically dispersed and 
last for only a few hours, often with intermittent sonar use even 
within this period. Most ASW sonars also have a narrow frequency band 
(typically less than one-third octave). These factors reduce the 
likelihood of sources causing significant masking. HF signals (above 10 
kHz) attenuate more rapidly in the water due to absorption than do 
lower frequency signals, thus producing only a very small zone of 
potential masking. If masking or communication impairment were to occur 
briefly, it would more likely be in the frequency range of MFAS (the 
more powerful source), which overlaps with some odontocete 
vocalizations (but few mysticete vocalizations); however, it would 
likely not mask the entirety of any particular vocalization, 
communication series, or other critical auditory cue, because the 
signal length, frequency, and duty cycle of the MFAS/HFAS signal does 
not perfectly resemble the characteristics of any single marine mammal 
species' vocalizations.
    Other sources used in Navy training and testing that are not 
explicitly addressed above, many of either higher frequencies (meaning 
that the sounds generated attenuate even closer to the source) or lower 
amounts of operation, are similarly not expected to result in masking. 
For the reasons described here, any limited masking that could 
potentially occur would be minor and short-term.
    In conclusion, masking is more likely to occur in the presence of 
broadband, relatively continuous noise sources such as from vessels, 
however, the duration of temporal and spatial overlap with any 
individual animal and the spatially separated sources that the Navy 
uses are not expected to result in more than short-term, low impact 
masking that will not affect reproduction or survival.
PTS From Sonar Acoustic Sources and Explosives and Tissue Damage From 
Explosives
    Tables 52 through 57 indicate the number of individuals of each 
species or stock for which Level A harassment in the form of PTS 
resulting from exposure to active sonar and/or explosives is estimated 
to occur. The number of individuals to potentially incur PTS annually 
(from sonar and explosives) for each species/stock ranges from 0 to 180 
(the 180 is for the Inland Washington stock of harbor porpoise), but is 
more typically 0 or 1. As described previously, no species/stocks have 
the potential to incur tissue damage from sonar or explosives.
    Data suggest that many marine mammals would deliberately avoid 
exposing themselves to the received levels of active sonar necessary to 
induce injury by moving away from or at least modifying their path to 
avoid a close approach. Additionally, in the unlikely event that an 
animal approaches the sonar-emitting vessel at a close distance, NMFS 
has determined that the mitigation measures (i.e., shutdown/powerdown 
zones for active sonar) would typically ensure that animals would not 
be exposed to injurious levels of sound. As discussed previously, the 
Navy utilizes both aerial (when available) and passive acoustic 
monitoring (during ASW exercises, passive acoustic detections are used 
as a cue for Lookouts' visual observations when passive acoustic assets 
are already participating in an activity) in addition to Lookouts on 
vessels to detect marine mammals for mitigation implementation. As 
discussed previously, these Level A harassment take numbers represent 
the maximum number of instances in which marine mammals would be 
reasonably expected to incur PTS, and we have analyzed them 
accordingly.
    If a marine mammal is able to approach a surface vessel within the 
distance necessary to incur PTS in spite of the mitigation measures, 
the likely speed of the vessel (nominally 10-15 kn) and relative motion 
of the vessel would make it very difficult for the animal to remain in 
range long enough to accumulate enough energy to result in more than a 
mild case of PTS. As discussed previously in relation to TTS, the 
likely consequences to the health of an individual that incurs PTS can 
range from mild to more serious dependent upon the degree of PTS and 
the frequency band it is in. The majority of any PTS incurred as a 
result of exposure to Navy sources would be expected to be in the 2-20 
kHz range (resulting from the most powerful hull-mounted sonar) and 
could overlap a small portion of the communication frequency range of 
many odontocetes, whereas other marine mammal groups have communication 
calls at lower frequencies. Because of the broadband nature of 
explosives, PTS incurred from exposure to explosives would occur over a 
lower, but wider, frequency range. For all but harbor porpoises, annual 
PTS take resulting from exposure to explosives is 1-5 per species or 
stock. For harbor porpoises, a fair portion of the takes by PTS result 
from explosive exposure. However, harbor porpoises are high frequency 
specialists and minor hearing loss at lower frequencies is expected to 
be less impactful than at higher frequencies because it is less likely 
to overlap or interfere with the sounds produced by harbor porpoises 
for communication or echolocation. Regardless of the frequency band, 
the more important point in this case is that any PTS accrued as a 
result of exposure to Navy activities would be expected to be of a 
small amount (single digits). Permanent loss of some degree of hearing 
is a normal occurrence for older animals, and many animals are able to 
compensate for the shift, both in old age or at younger ages as the 
result of stressor exposure. While a small loss of hearing sensitivity 
may include some degree of energetic costs for compensating or may mean 
some small loss of opportunities or detection capabilities, at the 
expected scale it would be unlikely to impact behaviors, opportunities, 
or detection capabilities to a degree that would interfere with 
reproductive success or survival.
    The Navy implements mitigation measures (described in the 
Mitigation Measures section) during explosive activities, including 
delaying detonations when a marine mammal is observed in the mitigation 
zone. Nearly all explosive events will occur during daylight hours to 
improve the sightability of marine mammals and thereby improve 
mitigation effectiveness. Observing for marine mammals during the 
explosive activities will include visual and passive acoustic detection 
methods (when they are available and part of the activity) before the 
activity begins, in order to cover the mitigation zones that can range 
from 500 yd (457 m) to 2,500 yd (2,286 m)

[[Page 72430]]

depending on the source (e.g., explosive sonobuoy, explosive torpedo, 
explosive bombs; see Tables 38-44). For all of these reasons, the 
mitigation measures associated with explosives are expected to be 
effective in preventing tissue damage to any potentially affected 
species or stocks, and no species or stocks are anticipated to incur 
tissue damage during the period of the rule.
Serious Injury and Mortality
    NMFS is authorizing a very small number of serious injuries or 
mortalities that could occur in the event of a ship strike. We note 
here that the takes from potential ship strikes enumerated below could 
result in non-serious injury, but their worst potential outcome 
(mortality) is analyzed for the purposes of the negligible impact 
determination.
    In addition, we discuss here the connection, and differences, 
between the legal mechanisms for authorizing incidental take under 
section 101(a)(5) for activities such as the Navy's testing and 
training in the NWTT Study Area, and for authorizing incidental take 
from commercial fisheries. In 1988, Congress amended the MMPA's 
provisions for addressing incidental take of marine mammals in 
commercial fishing operations. Congress directed NMFS to develop and 
recommend a new long-term regime to govern such incidental taking (see 
MMC, 1994). The need to develop a system suited to the unique 
circumstances of commercial fishing operations led NMFS to suggest a 
new conceptual means and associated regulatory framework. That concept, 
PBR, and a system for developing plans containing regulatory and 
voluntary measures to reduce incidental take for fisheries that exceed 
PBR were incorporated as sections 117 and 118 in the 1994 amendments to 
the MMPA. In Conservation Council for Hawaii v. National Marine 
Fisheries Service, 97 F. Supp. 3d 1210 (D. Haw. 2015), which concerned 
a challenge to NMFS' regulations and LOAs to the Navy for activities 
assessed in the 2013-2018 HSTT MMPA rulemaking, the Court ruled that 
NMFS' failure to consider PBR when evaluating lethal takes in the 
negligible impact analysis under section 101(a)(5)(A) violated the 
requirement to use the best available science.
    PBR is defined in section 3 of the MMPA as ``the maximum number of 
animals, not including natural mortalities, that may be removed from a 
marine mammal stock while allowing that stock to reach or maintain its 
optimum sustainable population'' (OSP) and, although not controlling, 
can be one measure considered among other factors when evaluating the 
effects of M/SI on a marine mammal species or stock during the section 
101(a)(5)(A) process. OSP is defined in section 3 of the MMPA as ``the 
number of animals which will result in the maximum productivity of the 
population or the species, keeping in mind the carrying capacity of the 
habitat and the health of the ecosystem of which they form a 
constituent element.'' Through section 2, an overarching goal of the 
statute is to ensure that each species or stock of marine mammal is 
maintained at or returned to its OSP.
    PBR values are calculated by NMFS as the level of annual removal 
from a stock that will allow that stock to equilibrate within OSP at 
least 95 percent of the time, and is the product of factors relating to 
the minimum population estimate of the stock (Nmin), the 
productivity rate of the stock at a small population size, and a 
recovery factor. Determination of appropriate values for these three 
elements incorporates significant precaution, such that application of 
the parameter to the management of marine mammal stocks may be 
reasonably certain to achieve the goals of the MMPA. For example, 
calculation of the minimum population estimate (Nmin) 
incorporates the level of precision and degree of variability 
associated with abundance information, while also providing reasonable 
assurance that the stock size is equal to or greater than the estimate 
(Barlow et al., 1995), typically by using the 20th percentile of a log-
normal distribution of the population estimate. In general, the three 
factors are developed on a stock-specific basis in consideration of one 
another in order to produce conservative PBR values that appropriately 
account for both imprecision that may be estimated, as well as 
potential bias stemming from lack of knowledge (Wade, 1998).
    Congress called for PBR to be applied within the management 
framework for commercial fishing incidental take under section 118 of 
the MMPA. As a result, PBR cannot be applied appropriately outside of 
the section 118 regulatory framework without consideration of how it 
applies within the section 118 framework, as well as how the other 
statutory management frameworks in the MMPA differ from the framework 
in section 118. PBR was not designed and is not used as an absolute 
threshold limiting commercial fisheries. Rather, it serves as a means 
to evaluate the relative impacts of those activities on marine mammal 
stocks. Even where commercial fishing is causing M/SI at levels that 
exceed PBR, the fishery is not suspended. When M/SI exceeds PBR in the 
commercial fishing context under section 118, NMFS may develop a take 
reduction plan, usually with the assistance of a take reduction team. 
The take reduction plan will include measures to reduce and/or minimize 
the taking of marine mammals by commercial fisheries to a level below 
the stock's PBR. That is, where the total annual human-caused M/SI 
exceeds PBR, NMFS is not required to halt fishing activities 
contributing to total M/SI but rather utilizes the take reduction 
process to further mitigate the effects of fishery activities via 
additional bycatch reduction measures. In other words, under section 
118 of the MMPA, PBR does not serve as a strict cap on the operation of 
commercial fisheries that may incidentally take marine mammals.
    Similarly, to the extent PBR may be relevant when considering the 
impacts of incidental take from activities other than commercial 
fisheries, using it as the sole reason to deny (or issue) incidental 
take authorization for those activities would be inconsistent with 
Congress's intent under section 101(a)(5), NMFS' long-standing 
regulatory definition of ``negligible impact,'' and the use of PBR 
under section 118. The standard for authorizing incidental take for 
activities other than commercial fisheries under section 101(a)(5) 
continues to be, among other things that are not related to PBR, 
whether the total taking will have a negligible impact on the species 
or stock. Nowhere does section 101(a)(5)(A) reference use of PBR to 
make the negligible impact finding or to authorize incidental take 
through multi-year regulations, nor does its companion provision at 
section 101(a)(5)(D) for authorizing non-lethal incidental take under 
the same negligible-impact standard. NMFS' MMPA implementing 
regulations state that take has a negligible impact when it does not 
``adversely affect the species or stock through effects on annual rates 
of recruitment or survival''--likewise without reference to PBR. When 
Congress amended the MMPA in 1994 to add section 118 for commercial 
fishing, it did not alter the standards for authorizing non-commercial 
fishing incidental take under section 101(a)(5), implicitly 
acknowledging that the negligible impact standard under section 
101(a)(5) is separate from the PBR metric under section 118. In fact, 
in 1994 Congress also amended section 101(a)(5)(E) (a separate 
provision governing commercial fishing incidental take for species 
listed under the ESA) to add compliance with the new section 118 but 
retained the standard of the

[[Page 72431]]

negligible impact finding under section 101(a)(5)(A) (and section 
101(a)(5)(D)), showing that Congress understood that the determination 
of negligible impact and the application of PBR may share certain 
features but are, in fact, different.
    Since the introduction of PBR in 1994, NMFS had used the concept 
almost entirely within the context of implementing sections 117 and 118 
and other commercial fisheries management-related provisions of the 
MMPA. Prior to the Court's ruling in Conservation Council for Hawaii v. 
National Marine Fisheries Service and consideration of PBR in a series 
of section 101(a)(5) rulemakings, there were a few examples where PBR 
had informed agency deliberations under other MMPA sections and 
programs, such as playing a role in the issuance of a few scientific 
research permits and subsistence takings. But as the Court found when 
reviewing examples of past PBR consideration in Georgia Aquarium v. 
Pritzker, 135 F. Supp. 3d 1280 (N.D. Ga. 2015), where NMFS had 
considered PBR outside the commercial fisheries context, ``it has 
treated PBR as only one `quantitative tool' and [has not used it] as 
the sole basis for its impact analyses.'' Further, the agency's 
thoughts regarding the appropriate role of PBR in relation to MMPA 
programs outside the commercial fishing context have evolved since the 
agency's early application of PBR to section 101(a)(5) decisions. 
Specifically, NMFS' denial of a request for incidental take 
authorization for the U.S. Coast Guard in 1996 seemingly was based on 
the potential for lethal take in relation to PBR and did not appear to 
consider other factors that might also have informed the potential for 
ship strike in relation to negligible impact (61 FR 54157; October 17, 
1996).
    The MMPA requires that PBR be estimated in SARs and that it be used 
in applications related to the management of take incidental to 
commercial fisheries (i.e., the take reduction planning process 
described in section 118 of the MMPA and the determination of whether a 
stock is ``strategic'' as defined in section 3), but nothing in the 
statute requires the application of PBR outside the management of 
commercial fisheries interactions with marine mammals. Nonetheless, 
NMFS recognizes that as a quantitative metric, PBR may be useful as a 
consideration when evaluating the impacts of other human-caused 
activities on marine mammal stocks. Outside the commercial fishing 
context, and in consideration of all known human-caused mortality, PBR 
can help inform the potential effects of M/SI requested to be 
authorized under section 101(a)(5)(A). As noted by NMFS and the U.S. 
Fish and Wildlife Service in our implementing regulations for the 1986 
amendments to the MMPA (54 FR 40341, September 29, 1989), the Services 
consider many factors, when available, in making a negligible impact 
determination, including, but not limited to, the status of the species 
or stock relative to OSP (if known); whether the recruitment rate for 
the species or stock is increasing, decreasing, stable, or unknown; the 
size and distribution of the population; and existing impacts and 
environmental conditions. In this multi-factor analysis, PBR can be a 
useful indicator for when, and to what extent, the agency should take 
an especially close look at the circumstances associated with the 
potential mortality, along with any other factors that could influence 
annual rates of recruitment or survival.
    When considering PBR during evaluation of effects of M/SI under 
section 101(a)(5)(A), we first calculate a metric for each species or 
stock that incorporates information regarding ongoing anthropogenic M/
SI from all sources into the PBR value (i.e., PBR minus the total 
annual anthropogenic mortality/serious injury estimate in the SAR), 
which is called ``residual PBR'' (Wood et al., 2012). We first focus 
our analysis on residual PBR because it incorporates anthropogenic 
mortality occurring from other sources. If the ongoing human-caused 
mortality from other sources does not exceed PBR, then residual PBR is 
a positive number, and we consider how the anticipated or potential 
incidental M/SI from the activities being evaluated compares to 
residual PBR using the framework in the following paragraph. If the 
ongoing anthropogenic mortality from other sources already exceeds PBR, 
then residual PBR is a negative number and we consider the M/SI from 
the activities being evaluated as described further below.
    When ongoing total anthropogenic mortality from the applicant's 
specified activities does not exceed PBR and residual PBR is a positive 
number, as a simplifying analytical tool we first consider whether the 
specified activities could cause incidental M/SI that is less than 10 
percent of residual PBR (the ``insignificance threshold,'' see below). 
If so, we consider M/SI from the specified activities to represent an 
insignificant incremental increase in ongoing anthropogenic M/SI for 
the marine mammal stock in question that alone (i.e., in the absence of 
any other take) will not adversely affect annual rates of recruitment 
and survival. As such, this amount of M/SI would not be expected to 
affect rates of recruitment or survival in a manner resulting in more 
than a negligible impact on the affected stock unless there are other 
factors that could affect reproduction or survival, such as Level A 
and/or Level B harassment, or other considerations such as information 
that illustrates uncertainty involved in the calculation of PBR for 
some stocks. In a few prior incidental take rulemakings, this threshold 
was identified as the ``significance threshold,'' but it is more 
accurately labeled an insignificance threshold, and so we use that 
terminology here, as we did in the AFTT final rule (83 FR 57076; 
November 14, 2018), and two-year rule extension (84 FR 70712; December 
23, 2019), as well as the HSTT final rule (83 FR 66846; December 27, 
2018) and two-year rule extension (85 FR 41780; July 10, 2020). 
Assuming that any additional incidental take by Level A or Level B 
harassment from the activities in question would not combine with the 
effects of the authorized M/SI to exceed the negligible impact level, 
the anticipated M/SI caused by the activities being evaluated would 
have a negligible impact on the species or stock. However, M/SI above 
the 10 percent insignificance threshold does not indicate that the M/SI 
associated with the specified activities is approaching a level that 
would necessarily exceed negligible impact. Rather, the 10 percent 
insignificance threshold is meant only to identify instances where 
additional analysis of the anticipated M/SI is not required because the 
negligible impact standard clearly will not be exceeded on that basis 
alone.
    Where the anticipated M/SI is near, at, or above residual PBR, 
consideration of other factors (positive or negative), including those 
outlined above, as well as mitigation is especially important to 
assessing whether the M/SI will have a negligible impact on the species 
or stock. PBR is a conservative metric and not sufficiently precise to 
serve as an absolute predictor of population effects upon which 
mortality caps would appropriately be based. For example, in some cases 
stock abundance (which is one of three key inputs into the PBR 
calculation) is underestimated because marine mammal survey data within 
the U.S. EEZ are used to calculate the abundance even when the stock 
range extends well beyond the U.S. EEZ. An underestimate of abundance 
could result in an underestimate of PBR. Alternatively, we sometimes 
may not

[[Page 72432]]

have complete M/SI data beyond the U.S. EEZ to compare to PBR, which 
could result in an overestimate of residual PBR. The accuracy and 
certainty around the data that feed any PBR calculation, such as the 
abundance estimates, must be carefully considered to evaluate whether 
the calculated PBR accurately reflects the circumstances of the 
particular stock. M/SI that exceeds residual PBR or PBR may still 
potentially be found to be negligible in light of other factors that 
offset concern, especially when robust mitigation and adaptive 
management provisions are included.
    In Conservation Council for Hawaii v. National Marine Fisheries 
Service, which involved the challenge to NMFS' issuance of LOAs to the 
Navy in 2013 for activities in the HSTT Study Area, the Court reached a 
different conclusion, stating, ``Because any mortality level that 
exceeds PBR will not allow the stock to reach or maintain its OSP, such 
a mortality level could not be said to have only a `negligible impact' 
on the stock.'' As described above, the Court's statement fundamentally 
misunderstands the two terms and incorrectly indicates that these 
concepts (PBR and ``negligible impact'') are directly connected, when 
in fact nowhere in the MMPA is it indicated that these two terms are 
equivalent.
    Specifically, PBR was designed as a tool for evaluating mortality 
and is defined as the number of animals that can be removed while 
``allowing that stock to reach or maintain its [OSP].'' OSP is defined 
as a population that falls within a range from the population level 
that is the largest supportable within the ecosystem to the population 
level that results in maximum net productivity, and thus is an 
aspirational management goal of the overall statute with no specific 
timeframe by which it should be met. PBR is designed to ensure minimal 
deviation from this overarching goal, with the formula for PBR 
typically ensuring that growth towards OSP is not reduced by more than 
10 percent (or equilibrates to OSP 95 percent of the time). Given that, 
as applied by NMFS, PBR certainly allows a stock to ``reach or maintain 
its [OSP]'' in a conservative and precautionary manner--and we can 
therefore clearly conclude that if PBR were not exceeded, there would 
not be adverse effects on the affected species or stocks. Nonetheless, 
it is equally clear that in some cases the time to reach this 
aspirational OSP level could be slowed by more than 10 percent (i.e., 
total human-caused mortality in excess of PBR could be allowed) without 
adversely affecting a species or stock through effects on its rates of 
recruitment or survival. Thus even in situations where the inputs to 
calculate PBR are thought to accurately represent factors such as the 
species' or stock's abundance or productivity rate, it is still 
possible for incidental take to have a negligible impact on the species 
or stock even where M/SI exceeds residual PBR or PBR.
    As noted above, in some cases the ongoing human-caused mortality 
from activities other than those being evaluated already exceeds PBR 
and, therefore, residual PBR is negative. In these cases (such as is 
specifically discussed for the CA/OR/WA stock of humpback whales 
below), any additional mortality, no matter how small, and no matter 
how small relative to the mortality caused by other human activities, 
would result in greater exceedance of PBR. PBR is helpful in informing 
the analysis of the effects of mortality on a species or stock because 
it is important from a biological perspective to be able to consider 
how the total mortality in a given year may affect the population. 
However, section 101(a)(5)(A) of the MMPA indicates that NMFS shall 
authorize the requested incidental take from a specified activity if we 
find that ``the total of such taking [i.e., from the specified 
activity] will have a negligible impact on such species or stock.'' In 
other words, the task under the statute is to evaluate the applicant's 
anticipated take in relation to their take's impact on the species or 
stock, not other entities' impacts on the species or stock. Neither the 
MMPA nor NMFS' implementing regulations call for consideration of other 
unrelated activities and their impacts on the species or stock. In 
fact, in response to public comments on the implementing regulations 
NMFS explained that such effects are not considered in making 
negligible impact findings under section 101(a)(5), although the extent 
to which a species or stock is being impacted by other anthropogenic 
activities is not ignored. Such effects are reflected in the baseline 
of existing impacts as reflected in the species' or stock's abundance, 
distribution, reproductive rate, and other biological indicators.
    NMFS guidance for commercial fisheries provides insight when 
evaluating the effects of an applicant's incidental take as compared to 
the incidental take caused by other entities. Parallel to section 
101(a)(5)(A), section 101(a)(5)(E) of the MMPA provides that NMFS shall 
allow the incidental take of ESA-listed endangered or threatened marine 
mammals by commercial fisheries if, among other things, the incidental 
M/SI from the commercial fisheries will have a negligible impact on the 
species or stock. As discussed earlier, the authorization of incidental 
take resulting from commercial fisheries and authorization for 
activities other than commercial fisheries are under two separate 
regulatory frameworks. However, when it amended the statute in 1994 to 
provide a separate incidental take authorization process for commercial 
fisheries, Congress kept the requirement of a negligible impact 
determination for this one category of species, thereby applying the 
standard to both programs. Therefore, while the structure and other 
standards of the two programs differ such that evaluation of negligible 
impact under one program may not be fully applicable to the other 
program, guidance on determining negligible impact for commercial 
fishing take authorizations can be informative when considering 
incidental take outside the commercial fishing context. In 1999, NMFS 
published criteria for making a negligible impact determination 
pursuant to section 101(a)(5)(E) of the MMPA in a notice of proposed 
permits for certain fisheries (64 FR 28800; May 27, 1999). Criterion 2 
stated if total human-related serious injuries and mortalities are 
greater than PBR, and fisheries-related mortality is less than 0.1 PBR, 
individual fisheries may be permitted if management measures are being 
taken to address non-fisheries-related serious injuries and 
mortalities. Those criteria further stated that when fisheries-related 
serious injury and mortality is less than 10 percent of the total, the 
appropriate management action is to address components that account for 
the major portion of the total. Criterion 2 addresses when total human-
caused mortality is exceeding PBR, but the activity being assessed is 
responsible for only a small portion of the mortality. The analytical 
framework we use here incorporates elements of the 1999 criteria 
developed for use under section 101(a)(5)(E), and because the 
negligible impact determination under section 101(a)(5)(A) focuses on 
the activity being evaluated, it is appropriate to utilize this 
parallel concept from the framework for section 101(a)(5)(E).
    Accordingly, we are using a similar criterion in our negligible 
impact analysis under section 101(a)(5)(A) to evaluate the relative 
role of an applicant's incidental take when other sources of take are 
causing PBR to be exceeded, but the take of the specified activity is 
comparatively small. Where this occurs, we may find that the impacts of 
the taking from the specified activity may (alone) be negligible even

[[Page 72433]]

when total human-caused mortality from all activities exceeds PBR if 
(in the context of a particular species or stock): The authorized 
mortality or serious injury would be less than or equal to 10 percent 
of PBR and management measures are being taken to address serious 
injuries and mortalities from the other activities (i.e., other than 
the specified activities covered by the incidental take authorization 
under consideration). In addition, we must also still determine that 
any impacts on the species or stock from other types of take (i.e., 
harassment) caused by the applicant do not combine with the impacts 
from mortality or serious injury addressed here to result in adverse 
effects on the species or stock through effects on annual rates of 
recruitment or survival.
    As discussed above, while PBR is useful in informing the evaluation 
of the effects of M/SI in section 101(a)(5)(A) determinations, it is 
just one consideration to be assessed in combination with other factors 
and is not determinative. For example, as explained above, the accuracy 
and certainty of the data used to calculate PBR for the species or 
stock must be considered. And we reiterate the considerations discussed 
above for why it is not appropriate to consider PBR an absolute cap in 
the application of this guidance. Accordingly, we use PBR as a trigger 
for concern while also considering other relevant factors to provide a 
reasonable and appropriate means of evaluating the effects of potential 
mortality on rates of recruitment and survival, while acknowledging 
that it is possible to exceed PBR (or exceed 10 percent of PBR in the 
case where other human-caused mortality is exceeding PBR but the 
specified activity being evaluated is an incremental contributor, as 
described in the last paragraph) by some small amount and still make a 
negligible impact determination under section 101(a)(5)(A).
    We note that on June 17, 2020 NMFS finalized new Criteria for 
Determining Negligible Impact under MMPA section 101(a)(5)(E). The 
guidance explicitly notes the differences in the negligible impact 
determinations required under section 101(a)(5)(E), as compared to 
sections 101(a)(5)(A) and 101(a)(5)(D), and specifies that the 
procedure in that document is limited to how the agency conducts 
negligible impact analyses for commercial fisheries under section 
101(a)(5)(E). In the proposed rule (and above), NMFS has described its 
method for considering PBR to evaluate the effects of potential 
mortality in the negligible impact analysis. NMFS has reviewed the 2020 
guidance and determined that our consideration of PBR in the evaluation 
of mortality as described above and in the proposed rule remains 
appropriate for use in the negligible impact analysis for the Navy's 
activities in the NWTT Study Area under section 101(a)(5)(A).
    Our evaluation of the M/SI for each of the species and stocks for 
which mortality or serious injury could occur follows. No M/SI are 
anticipated from the Navy's sonar activities or use of explosives.
    We first consider maximum potential incidental M/SI from the Navy 
and NMFS' ship strike analysis for the affected mysticetes and sperm 
whales (see Table 51; updated from the proposed rule) in consideration 
of NMFS' threshold for identifying insignificant M/SI take. By 
considering the maximum potential incidental M/SI in relation to PBR 
and ongoing sources of anthropogenic mortality, we begin our evaluation 
of whether the incremental addition of M/SI through the Navy's 
potential ship strikes may affect the species' or stock's annual rates 
of recruitment or survival. We also consider the interaction of those 
mortalities with incidental taking of that species or stock by 
harassment pursuant to the specified activity.
    Based on the methods discussed previously, NMFS believes that 
mortal takes of three large whales could occur over the course of the 
seven-year rule. Of the three total M/SI takes, the rule authorizes no 
more than two from any of the following species/stocks over the seven-
year period: Fin whale (which may come from either the Northeast 
Pacific or CA/OR/WA stock) and humpback whale (which may come from 
either the Central North Pacific or CA/OR/WA stock). Of the three total 
M/SI takes, the rule also authorizes no more than one mortality from 
any of the following species/stocks over the seven-year period: Sperm 
whale (CA/OR/WA stock), minke whale (CA/OR/WA stock), and gray whale 
(Eastern North Pacific stock). We do not anticipate, nor authorize, M/
SI takes from ship strikes for blue whale (Eastern North Pacific 
stock), minke whale (Alaska stock), or sei whale (Eastern North Pacific 
stock). This means an annual average of 0.14 whales from each species 
or stock where one mortality may occur and an annual average of 0.29 
whales from each species or stock where two mortalities may occur, as 
described in Table 51 (i.e., 1 or 2 takes over 7 years divided by 7 to 
get the annual number).

                                                    Table 51--Summary Information Related to Mortalities Requested for Ship Strike, 2020-2027
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                 Fisheries      Vessel                           Residual
                                                          Annual               interactions   collisions  Annual navy             PBR-PBR
                                                        authorized                (Y/N);        (Y/N);        HSTT                 minus                                          Recent UME (Y/
                                               Stock      take by     Total     annual rate  annual rate   authorized           annual  M/                                        N); number and
              Species (stock)                abundance    serious   annual  M/ of M/SI from    of M/SI    take  (2018-  PBR *     SI and              Stock trend * \4\             year (since
                                             (Nbest) *   injury or   SI * \2\    fisheries   from vessel   2025) \5\               HSTT                                                2007)
                                                         mortality             interactions    collision                        authorized
                                                            \1\                      *            *                              take \3\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Fin whale (Northeast Pacific).............       3,168        0.29        0.4          N; 0       Y; 0.4            0      5.1         4.7  [uarr]..............................               N
Fin whale (CA/OR/WA)......................       9,029        0.29    >= 43.5     Y; >= 0.5        Y; 43         0.29       81        37.2  [uarr]..............................               N
Humpback whale (Central North Pacific)....      10,103        0.29         25        Y; 9.5   \6\ Y; 3.9         0.29       83        57.7  [uarr]..............................               N
Humpback whale............................       2,900        0.29    >= 42.1    Y; >= 17.3        Y; 22         0.14     33.4        -8.8  Stable ([uarr] (historically).......               N
(CA/OR/WA)................................
Sperm whale (CA/OR/WA)....................       1,997        0.14        0.6        Y; 0.6         N; 0            0      2.5         1.8  Unknown.............................               N
Minke whale (CA/OR/WA)....................         636        0.14     >= 1.3     Y; >= 1.3         N; 0            0      3.5         2.2  Unknown.............................               N
Gray whale (Eastern North Pacific)........      26,960        0.14        139        Y; 9.6       Y; 0.8         0.29      801       661.6  [uarr]..............................    Y, 384, 2019
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
*Presented in the 2019 SARs or most recent SAR.
\1\This column represents the annual take by serious injury or mortality by vessel collision and was calculated by the number of mortalities authorized divided by seven years (the length of
  the rule and LOAs).
\2\This column represents the total number of incidents of M/SI that could potentially accrue to the specified species or stock. This number comes from the SAR, but deducts the takes accrued
  from either NMFS Science Center research activities or Navy strikes authorized for training and testing activities. No NMFS Science Center or Navy M/SI takes for these stocks are recorded in
  the SARs and no NMFS Science Center M/SI incidental takes have been authorized.
\3\This value represents the calculated PBR minus the average annual estimate of ongoing anthropogenic mortalities (i.e., total annual human-caused M/SI column and the annual authorized take
  from the HSTT column). This value represents the total PBR for the stock in the stock's entire range.
\4\See relevant SARs for more information regarding stock status and trends.
\5\ This column represents annual M/SI take authorized through NMFS' current HSTT regulations/LOAs (85 FR 41780). On July 10, 2020, NMFS effectively extended the current HSTT regulations by
  two years, replacing the five-year HSTT regulations with seven-year regulations. These regulations authorized the same number of M/SI for the same species/stocks, but over a seven-year
  period rather than a five-year period (resulting in slightly lower annual authorized take for each species/stock). See the 2020 HSTT final rule for more details (85 FR 41780, July 10, 2020).
\6\ This value represents average annual observed M/SI from ship strikes in Alaska (2.5) and Hawaii (1.4). For the purposes of analysis of potential ship strikes (see the Estimated Take of
  Marine Mammals section) we incorporated only Alaska ship strikes as only these ship strikes have the potential to overlap with the NWTT Study Area.


[[Page 72434]]

Stocks With M/SI Below the Insignificance Threshold

    As noted above, for a species or stock with incidental M/SI less 
than 10 percent of residual PBR, we consider M/SI from the specified 
activities to represent an insignificant incremental increase in 
ongoing anthropogenic M/SI that alone (i.e., in the absence of any 
other take and barring any other unusual circumstances) will clearly 
not adversely affect annual rates of recruitment and survival. In this 
case, as shown in Table 51, the following species or stocks have 
potential M/SI from ship strike authorized below their insignificance 
threshold: Fin whale (both the Northeast Pacific and CA/OR/WA stocks), 
humpback whale (Central North Pacific stock), sperm whale (CA/OR/WA 
stock), minke whale (CA/OR/WA stock), and gray whale (Eastern North 
Pacific stock). While the authorized M/SI of gray whales (Eastern North 
Pacific stock) is below the insignificance threshold, because of the 
recent UME, we further address how the authorized M/SI and the UME 
inform the negligible impact determination immediately below. For the 
other five stocks with authorized M/SI below the insignificance 
threshold, there are no other known factors, information, or unusual 
circumstances that indicate anticipated M/SI below the insignificance 
threshold could have adverse effects on annual rates of recruitment or 
survival and they are not discussed further. For the remaining one 
stock (CA/OR/WA stock of humpback whales) with potential M/SI above the 
insignificance threshold, how that M/SI compares to residual PBR, as 
well as additional factors, are discussed below as well.

Gray Whales (Eastern North Pacific stock)

    For this stock, PBR is currently set at 801. The total annual M/SI 
from other sources of anthropogenic mortality is estimated to be 139. 
In addition, 0.29 annual mortalities have been authorized for this same 
stock in the current incidental take regulations for Navy testing and 
training activities in the HSTT Study Area (85 FR 41780; July 10, 
2020). This yields a residual PBR of 661.6. The additional 0.29 annual 
mortalities that are authorized in this rule are well below the 
insignificance threshold (10 percent of residual PBR, in this case 
66.2). Nonetheless, since January 2019, gray whale strandings along the 
west coast of North America have been significantly higher than the 
previous 18-year average. Preliminary findings from necropsies have 
shown evidence of poor to thin body condition. The seasonal pattern of 
elevated strandings in the spring and summer months is similar to that 
of the previous gray whale UME in 1999-2000, and the current UME is 
continuing to follow a similar pattern with a decrease in strandings in 
late summer and fall. However, combined with other annual human-caused 
mortalities, and viewed through the PBR lens (for human-caused 
mortalities), total human-caused mortality (inclusive of the potential 
for additional UME deaths) would still fall well below residual PBR and 
the insignificance threshold. Because of the abundance, population 
trend (increasing, despite the UME in 1999-2000), and residual PBR 
(661.6) of this stock, this UME is not expected to have impacts on the 
population rate that, in combination with the effects of the authorized 
mortality, would affect annual rates of recruitment or survival.
Stocks with M/SI above the Insignificance Threshold
    The CA/OR/WA stock of humpback whales is the only stock with M/SI 
above the insignificance threshold. For this stock, PBR is currently 
set at 16.7 for U.S. waters and 33.4 for the stock's entire range. The 
total annual M/SI is estimated at greater than or equal to 42.1. 
Combined with 0.14 annual mortalities that have been authorized for 
this same stock in the current incidental take regulations for Navy 
testing and training activities in the HSTT Study Area (85 FR 41780; 
July 10, 2020), this yields a residual PBR of -8.8. NMFS is authorizing 
up to 2 M/SI takes over the seven-year duration of this rule, which is 
0.29 M/SI takes annually for the purposes of comparing to PBR and 
considering other possible effects on annual rates of recruitment and 
survival. This means that with the additional 0.29 M/SI annual takes 
authorized in this rule, residual PBR would be exceeded by 9.1.
    In the commercial fisheries setting for ESA-listed marine mammals 
(which can be informative for the non-fisheries incidental take 
setting, in that a negligible impact determination is required that is 
based on the assessment of take caused by the activity being analyzed), 
NMFS may find the impact of the authorized take from a specified 
activity to be negligible even if total human-caused mortality exceeds 
PBR, if the authorized mortality is less than 10 percent of PBR and 
management measures are being taken to address serious injuries and 
mortalities from the other activities causing mortality (i.e., other 
than the specified activities covered by the incidental take 
authorization under consideration). When those considerations are 
applied in the section 101(a)(5)(A) context here, the authorized lethal 
take (0.29 annually) of humpback whales from the CA/OR/WA stock is 
significantly less than 10 percent of PBR (in fact less than 1 percent 
of 33.4) and there are management measures in place to address M/SI 
from activities other than those the Navy is conducting (as discussed 
below).
    Based on identical simulations as those conducted to identify 
Recovery Factors for PBR in Wade et al. (1998), but where values less 
than 0.1 were investigated (P. Wade, pers. comm.), we predict that 
where the mortality from a specified activity does not exceed Nmin * 
\1/2\ Rmax * 0.013, the contemplated mortality for the specific 
activity will not delay the time to recovery by more than 1 percent. 
For this stock of humpback whales, Nmin * \1/2\ Rmax * 0.013 = 1.45 and 
the annual mortality authorized is 0.29 (i.e., less than 1.45). This 
means that the mortality authorized in this rule for NWTT activities 
will not delay the time to recovery to OSP by more than 1 percent.
    NMFS must also ensure that impacts by the applicant on the species 
or stock from other types of take (i.e., harassment) do not combine 
with the impacts from M/SI to adversely affect the species or stock via 
impacts on annual rates of recruitment or survival, which is discussed 
further below in the species- and stock-specific section.
    In August 2020, NMFS published 2019 SARs in which PBR is reported 
as 33.4 with the predicted average annual mortality greater than or 
equal to 42.1 (including 22 estimated from vessel collisions and 
greater than 17.3 observed fisheries interactions). While the observed 
M/SI from vessel strikes remains low at 2.2 per year, the 2018 and 2019 
SARs rely on a new method to estimate annual deaths by ship strike 
utilizing an encounter theory model that combined species distribution 
models of whale density, vessel traffic characteristics, and whale 
movement patterns obtained from satellite-tagged animals in the region 
to estimate encounters that would result in mortality (Rockwood et al., 
2017). The model predicts 22 annual mortalities of humpback whales from 
this stock from vessel strikes. The authors (Rockwood et al., 2017) do 
not suggest that ship strikes suddenly increased to 22. In fact, the 
model is not specific to a year, but rather offers a generalized 
prediction of ship strikes off the U.S. West Coast. Therefore, if the 
Rockwood et al. (2017) model is an accurate representation of vessel 
strike, then similar levels of ship

[[Page 72435]]

strike have been occurring in past years as well. Put another way, if 
the model is correct, for some number of years total human-caused 
mortality has been significantly underestimated, and PBR has been 
similarly exceeded by a notable amount, and yet the CA/OR/WA stock of 
humpback whales is considered stable nevertheless.
    The CA/OR/WA stock of humpback whales experienced a steady increase 
from the 1990s through approximately 2008, and more recent estimates 
through 2014 indicate a leveling off of the population size. This stock 
is comprised of the feeding groups of three DPSs. Two DPSs associated 
with this stock are listed under the ESA as either endangered (Central 
America DPS) or threatened (Mexico DPS), while the third (Hawaii DPS) 
is not listed. Humpback whales from the Hawaii DPS are anticipated to 
be rare in the NWTT Study Area with a probability of the DPS foraging 
in the waters of the Study Area of 1.6 percent (including summer areas 
of Oregon/California and Southern British Columbia/Washington from Wade 
(2017)). Humpback whales from the Mexico DPS and Central America DPS 
are anticipated to be more prevalent in the Study Area with 
probabilities of the DPSs foraging in the waters of the Study Area of 
31.7 and 100 percent, respectively (including summer areas of Oregon/
California and Southern British Columbia/Washington from Wade (2017)). 
As described in the final rule Identifying 14 DPSs of the Humpback 
Whale and Revision of Species-Wide Listing (81 FR 62260, September 8, 
2016), the Mexico DPS was initially proposed not to be listed as 
threatened or endangered, but the final decision was changed in 
consideration of a new abundance estimate using a new methodology that 
was more accurate (less bias from capture heterogeneity and lower 
coefficient of variation) and resulted in a lower abundance than was 
previously estimated. To be clear, the new abundance estimate did not 
indicate that the numbers had decreased, but rather, the more accurate 
new abundance estimate (3,264), derived from the same data but based on 
an integrated spatial multi-strata mark recapture model (Wade et al., 
2016), was simply notably lower than earlier estimates, which were 
6,000-7,000 from the SPLASH project (Calambokidis et al., 2008) or 
higher (Barlow et al., 2011). The updated abundance was still higher 
than 2,000, which is the Biological Review Team's (BRT) threshold 
between ``not likely to be at risk of extinction due to low abundance 
alone'' and ``increasing risk from factors associated with low 
abundance.'' Further, the BRT concluded that the DPS was unlikely to be 
declining because of the population growth throughout most of its 
feeding areas, in California/Oregon and the Gulf of Alaska, but they 
did not have evidence that the Mexico DPS was actually increasing in 
overall population size.
    As discussed earlier, we also take into consideration management 
measures in place to address M/SI caused by other activities. 
Commercial fisheries such as crab pot, gillnet, and prawn fisheries are 
a significant source of mortality and serious injury for humpback 
whales and other large whales and, unfortunately, have increased 
mortalities and serious injuries over recent years (Carretta et al., 
2019). However, the 2019 draft SAR notes that a recent increase in 
disentanglement efforts has resulted in an increase in the fraction of 
cases that are reported as non-serious injuries as a result of 
successful disentanglement. More importantly, since 2015, NMFS has 
engaged in a multi-stakeholder process in California (including 
California State resource managers, fishermen, non-governmental 
organizations (NGOs), and scientists) to identify and develop solutions 
and make recommendations to regulators and the fishing industry for 
reducing whale entanglements (see http://www.opc.ca.gov/whale-entanglement-working-group/), referred to as the Whale Entanglement 
Working Group. The Whale Entanglement Working Group has made 
significant progress since 2015 and is tackling the problem from 
multiple angles, including:
     Development of Fact Sheets and Best Practices (BMPs) for 
specific Fisheries issues (e.g., California Dungeness Crab Fishing BMPs 
and the 2018-2019 Best Fishing Practices Guide);
     A Risk Assessment and Mitigation Program (RAMP) to support 
the state of California in working collaboratively with experts 
(fishermen, researchers, NGOs, etc.) to identify and assess elevated 
levels of entanglement risk and determine the need for management 
options to reduce risk of entanglement; and
     Support of pilot studies to test new fisheries 
technologies to reduce take (e.g., exploring Ropeless Fishing 
Technologies for the California Dungeness Crab Fishery).
    The Working Group meets regularly, posts reports and annual 
recommendations, and makes all of their products and guidance documents 
readily accessible for the public (https://opc.ca.gov/risk-assessment-and-mitigation-program-ramp/).
    In early 2019, as a result of a litigation settlement agreement, 
the California Department of Fish and Wildlife (CDFW) closed the 
Dungeness crab fishery three months early for the year, which is 
expected to reduce the number of likely entanglements. The agreement 
also limits the fishery duration over the next couple of years and has 
different triggers to reduce or close it further. Further, pursuant to 
the settlement, CDFW is required to apply for a Section 10 Incidental 
Take Permit under the ESA to address protected species interactions 
with fishing gear and crab fishing gear (pots). Any request for such a 
permit must include a Conservation Plan that specifies, among other 
things, what steps the applicant will take to minimize and mitigate the 
impacts, and the funding that will be available to implement such 
steps. On May 15, 2020, CDFW submitted a draft Conservation Plan to 
NMFS and CDFW's development of this plan continues. The May 2020 draft 
plan may be viewed here: https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=179066&inline. Additional information about 
CDFWs planned application for an ITP can be accessed at the CDFW Whale 
Safe Fisheries web page (https://wildlife.ca.gov/Conservation/Marine/Whale-Safe-Fisheries). A critical element of CDFW's approach to 
reducing the risk of entanglement includes the implementation of RAMP 
regulations. These proposed regulations may be found at: https://wildlife.ca.gov/Notices/Regulations/RAMP.
    Regarding measures in place to reduce mortality from other sources, 
the Channel Islands NMS staff coordinates, collects, and monitors whale 
sightings in and around a Whale Advisory Zone and the Channel Islands 
NMS region, which is within the area of highest vessel strike mortality 
(90th percentile) for humpback whales on the U.S. West Coast (Rockwood 
et al., 2017). The seasonally established Whale Advisory Zone spans 
from Point Arguello to Dana Point, including the Traffic Separation 
Schemes in the Santa Barbara Channel and San Pedro Channel. Vessels 
transiting the area from June through November are recommended to 
exercise caution and voluntarily reduce speed to 10 kn or less for 
blue, humpback, and fin whales. Channel Island NMS observers collect 
information from aerial surveys conducted by NOAA, the U.S. Coast 
Guard, California Department of Fish and Game, and Navy chartered 
aircraft. Information on seasonal presence, movement, and general

[[Page 72436]]

distribution patterns of large whales is shared with mariners, NMFS' 
Office of Protected Resources, the U.S. Coast Guard, the California 
Department of Fish and Game, the Santa Barbara Museum of Natural 
History, the Marine Exchange of Southern California, and whale 
scientists. Although well south of the NWTT Study Area, reduced vessel 
strikes in this area benefit humpback whales throughout the stock's 
range. Real time and historical whale observation data collected from 
multiple sources can be viewed on the Point Blue Whale Database.
    More recently, similar efforts to reduce entanglement risk and 
severity have also been initiated in Oregon and Washington. Both Oregon 
and Washington are developing applications for ESA Incidental Take 
Permits for their commercial crab fisheries, and all three West Coast 
states regularly coordinate on their Conservation Plan proposals and 
schedules. Both states advocate similar best practices for their 
fishermen as California, and they are taking regulatory steps related 
to gear marking and pot limits. For example, they have recently 
implemented or proposed regulations intended to reduce entanglement 
risk or increase the identification of fishing gear entangling whales. 
Additional information about Oregon's efforts may be found at https://www.dfw.state.or.us/MRP/shellfish/commercial/crab/whale_entanglement.asp. A summary of WDFW whale entanglement risk 
reduction information may be found at: https://wdfw.wa.gov/sites/default/files/2020-01/5_whale_ent_in_coastal_crab_fishery_jan_2020_revised.pdf .
    In this case, 0.29 M/SI annually means the potential for two 
mortalities in one or two of the seven years and zero mortalities in 
five or six of those seven years. Therefore, the Navy will not be 
contributing to the total human-caused mortality at all in at least 
five of the seven, or 71.4 percent, of the years covered by this rule. 
That means that even if a humpback whale from the CA/OR/WA stock were 
to be struck, in at least five of the seven years there could be no 
effect on annual rates of recruitment or survival from Navy-caused M/
SI. Additionally, the loss of a male would have far less, if any, of an 
effect on population rates than the loss of a reproductive female (as 
males are known to mate with multiple females), and absent any 
information suggesting that one sex is more likely to be struck than 
another, we can reasonably assume that there is a 50 percent chance 
that the strikes authorized by this rule would be males, thereby 
further decreasing the likelihood of impacts on the population rate. In 
situations like this where potential M/SI is fractional, consideration 
must be given to the lessened impacts anticipated due to the absence of 
any M/SI in five or six of the years and due to the fact that strikes 
could be males.
    Lastly, we reiterate that PBR is a conservative metric and also not 
sufficiently precise to serve as an absolute predictor of population 
effects upon which mortality caps would appropriately be based. Wade et 
al. (1998), authors of the paper from which the current PBR equation is 
derived, note that ``Estimating incidental mortality in one year to be 
greater than the PBR calculated from a single abundance survey does not 
prove the mortality will lead to depletion; it identifies a population 
worthy of careful future monitoring and possibly indicates that 
mortality-mitigation efforts should be initiated.''
    The information included here illustrates that this humpback whale 
stock is currently stable, the potential (and authorized) mortality is 
well below 10 percent (0.87 percent) of PBR, and management actions are 
in place to minimize both fisheries interactions and ship strike from 
other vessel activity in one of the highest-risk areas for strikes. 
More specifically, although the total human-caused mortality exceeds 
PBR, the authorized mortality for the Navy's specified activities would 
incrementally contribute less than 1 percent of that and, further, 
given the fact that it would occur in only one or two of the seven 
years with a 50 percent chance of the take involving males (far less 
impactful to the population), the potential impacts on population rates 
are even less. Based on all of the considerations described above, 
including consideration of the fact that the authorized M/SI of 0.29 
will not delay the time to recovery by more than 1 percent, the 
potential lethal take from Navy activities, alone, are unlikely to 
adversely affect the CA/OR/WA stock of humpback whales through effects 
on annual rates of recruitment or survival. Nonetheless, the fact that 
total human-caused mortality exceeds PBR necessitates close attention 
to the remainder of the impacts (i.e., harassment) on the CA/OR/WA 
stock of humpback whales from the Navy's activities to ensure that the 
total authorized takes will have a negligible impact on the species and 
stock. Therefore, this information will be considered in combination 
with our assessment of the impacts of authorized harassment takes in 
the Group and Species-Specific Analyses section that follows.

Group and Species-Specific Analyses

    In this section, we build on the general analysis that applies to 
all marine mammals in the NWTT Study Area from the previous section, 
and include first information and analysis that applies to mysticetes 
or, separately, odontocetes, or pinnipeds, and then within those three 
sections, more specific information that applies to smaller groups, 
where applicable, and the affected species or stocks. The specific 
authorized take numbers are also included in the analyses below, and so 
here we provide some additional context and discussion regarding how we 
consider the authorized take numbers in those analyses.
    The maximum amount and type of incidental take by harassment of 
marine mammals reasonably likely to occur from exposures to sonar and 
other active acoustic sources and explosions and therefore authorized 
during the seven-year training and testing period are shown in Tables 
32 and 33. The vast majority of predicted exposures (greater than 99 
percent) are expected to be Level B harassment (TTS and behavioral 
reactions) from acoustic and explosive sources during training and 
testing activities at relatively low received levels.
    In the discussions below, the estimated takes by Level B harassment 
represent instances of take, not the number of individuals taken (the 
much lower and less frequent Level A harassment takes are far more 
likely to be associated with separate individuals), and in some cases 
individuals may be taken more than one time. Below, we compare the 
total take numbers (including PTS, TTS, and behavioral disturbance) for 
species or stocks to their associated abundance estimates to evaluate 
the magnitude of impacts across the species or stock and to 
individuals. Generally, when an abundance percentage comparison is 
below 100, it suggests the following: (1) That not all of the 
individuals will be taken; (2) that, barring specific circumstances 
suggesting repeated takes of individuals (such as in circumstances 
where all activities resulting in take are focused in one area and time 
where the same individual marine mammals are known to congregate, such 
as pinnipeds at a haulout), the average or expected number of days for 
those individuals taken is one per year; and (3) that we would not 
expect any individuals to be taken more than a few times in a year, or 
for those days to be sequential. When it is more than 100 percent, it 
means there will definitely be some number of repeated takes of 
individuals. For

[[Page 72437]]

example, if the percentage is 300, the average would be each individual 
is taken on three days in a year if all were taken, but it is more 
likely that some number of individuals will be taken more than three 
times and some number of individuals fewer or not at all. While it is 
not possible to know the maximum number of days across which 
individuals of a stock might be taken, in acknowledgement of the fact 
that it is more than the average, for the purposes of this analysis, we 
assume a number approaching twice the average. For example, if the 
percentage of take compared to the abundance is 800, we estimate that 
some individuals might be taken as many as 16 times. Those comparisons 
are included in the sections below.
    To assist in understanding what this analysis means, we clarify a 
few issues related to estimated takes and the analysis here. An 
individual that incurs a PTS or TTS take may sometimes, for example, 
also be subject to behavioral disturbance at the same time. As 
described above in this section, the degree of PTS, and the degree and 
duration of TTS, expected to be incurred from the Navy's activities are 
not expected to impact marine mammals such that their reproduction or 
survival could be affected. Similarly, data do not suggest that a 
single instance in which an animal accrues PTS or TTS and is also 
subjected to behavioral disturbance would result in impacts to 
reproduction or survival. Alternately, we recognize that if an 
individual is subjected to behavioral disturbance repeatedly for a 
longer duration and on consecutive days, effects could accrue to the 
point that reproductive success is jeopardized, although those sorts of 
impacts are generally not expected to result from these activities. 
Accordingly, in analyzing the number of takes and the likelihood of 
repeated and sequential takes, we consider the total takes, not just 
the takes by Level B harassment by behavioral disturbance, so that 
individuals potentially exposed to both threshold shift and behavioral 
disturbance are appropriately considered. The number of Level A 
harassment takes by PTS are so low (and zero in most cases) compared to 
abundance numbers that it is considered highly unlikely that any 
individual would be taken at those levels more than once.
    Use of sonar and other transducers would typically be transient and 
temporary. The majority of acoustic effects to marine mammals from 
sonar and other active sound sources during testing and training 
activities would be primarily from ASW events. It is important to note 
that unlike other Navy Training and Testing Study Areas, there are no 
MTEs planned for the NWTT Study Area. On the less severe end, exposure 
to comparatively lower levels of sound at a detectably greater distance 
from the animal, for a few or several minutes, could result in a 
behavioral response such as avoiding an area that an animal would 
otherwise have moved through or fed in, or breaking off one or a few 
feeding bouts. More severe behavioral effects could occur when an 
animal gets close enough to the source to receive a comparatively 
higher level of sound, is exposed continuously to one source for a 
longer time, or is exposed intermittently to different sources 
throughout a day. Such effects might result in an animal having a more 
severe flight response and leaving a larger area for a day or more, or 
potentially losing feeding opportunities for a day. However, such 
severe behavioral effects are expected to occur infrequently.
    Occasional, milder behavioral reactions are unlikely to cause long-
term consequences for individual animals or populations, and even if 
some smaller subset of the takes are in the form of a longer (several 
hours or a day) and more severe response, if they are not expected to 
be repeated over sequential days, impacts to individual fitness are not 
anticipated. Nearly all studies and experts agree that infrequent 
exposures of a single day or less are unlikely to impact an 
individual's overall energy budget (Farmer et al., 2018; Harris et al., 
2017; King et al., 2015; NAS 2017; New et al., 2014; Southall et al., 
2007; Villegas-Amtmann et al., 2015).
    If impacts to individuals are of a magnitude or severity such that 
either repeated and sequential higher severity impacts occur (the 
probability of this goes up for an individual the higher total number 
of takes it has) or the total number of moderate to more severe impacts 
occurs across sequential days, then it becomes more likely that the 
aggregate effects could potentially interfere with feeding enough to 
reduce energy budgets in a manner that could impact reproductive 
success via longer cow-calf intervals, terminated pregnancies, or calf 
mortality. It is important to note that these impacts only accrue to 
females, which only comprise a portion of the population (typically 
approximately 50 percent). Based on energetic models, it takes 
energetic impacts of a significantly greater magnitude to cause the 
death of an adult marine mammal, and females will always terminate a 
pregnancy or stop lactating before allowing their health to 
deteriorate. Also, the death of an adult female has significantly more 
impact on population growth rates than reductions in reproductive 
success, while the death of an adult male has very little effect on 
population growth rates. However, as explained earlier, such severe 
impacts from the Navy's activities would be very infrequent and not 
likely to occur at all for most species and stocks. Even for the one 
stock of harbor seals where it is possible for a small number of 
females to experience reproductive effects, we explain below why there 
still will be no effect on rates of recruitment or survival.
    The analyses below in some cases address species collectively if 
they occupy the same functional hearing group (i.e., low, mid, and 
high-frequency cetaceans), share similar life history strategies, and/
or are known to behaviorally respond similarly to acoustic stressors. 
Because some of these groups or species share characteristics that 
inform the impact analysis similarly, it would be duplicative to repeat 
the same analysis for each species. In addition, similar species 
typically have the same hearing capabilities and behaviorally respond 
in the same manner.
    Thus, our analysis below considers the effects of the Navy's 
activities on each affected species or stock even where discussion is 
organized by functional hearing group and/or information is evaluated 
at the group level. Where there are meaningful differences between a 
species or stock that would further differentiate the analysis, they 
are either described within the section or the discussion for those 
species or stocks is included as a separate subsection. Specifically 
below, we first give broad descriptions of the mysticete, odontocete, 
and pinniped groups and then differentiate into further groups as 
appropriate.
Mysticetes
    This section builds on the broader discussion above and brings 
together the discussion of the different types and amounts of take that 
different species and stocks could potentially or will likely incur, 
the applicable mitigation, and the status of the species and stocks to 
support the negligible impact determinations for each species or stock. 
We have described (above in the General Negligible Impact Analysis 
section) the unlikelihood of any masking having effects that will 
impact the reproduction or survival of any of the individual marine 
mammals affected by the Navy's activities. We have also described in 
the Potential Effects of Specified Activities on Marine

[[Page 72438]]

Mammals and their Habitat section of the proposed rule that the 
specified activities would not have adverse or long-term impacts on 
marine mammal habitat, and therefore the unlikelihood of any habitat 
impacts affecting the reproduction or survival of any individual marine 
mammals affected by the Navy's activities. No new information has been 
received that affects this analysis and conclusion, although additional 
mitigation further reducing impacts to Mysticetes and their habitat has 
been added, as described in the Mitigation Measures section. For 
mysticetes, there is no predicted PTS from sonar or explosives and no 
predicted tissue damage from explosives for any species or stock. Much 
of the discussion below focuses on the behavioral effects and the 
mitigation measures that reduce the probability or severity of effects. 
Because there are species-specific and stock-specific considerations as 
well as M/SI take authorized for several stocks, at the end of the 
section we break out our findings on a species-specific and, for one 
species, stock-specific basis.
    In Table 52 below for mysticetes, we indicate for each species and 
stock the total annual numbers of take by mortality, Level A and Level 
B harassment, and a number indicating the instances of total take as a 
percentage of abundane.

  Table 52--Annual Estimated Takes by Level B Harassment, Level A Harassment, and Mortality for Mysticetes and Number Indicating the Instances of Total
                                                        Take as a Percentage of Species Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                 Instances of indicated types of incidental take  (not all takes
                                                   represent separate individuals, especially for disturbance)
                                               ------------------------------------------------------------------                           Instances of
                                                    Level B harassment        Level A harassment                                Abundance    total take
           Species                  Stock      -----------------------------------------------------              Total takes  (NMFS SARs)       as
                                                               TTS  (may                                                            *        percentage
                                                 Behavioral  also include                  Tissue     Mortality                             of abundance
                                                disturbance                    PTS         damage
                                                             disturbance)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Suborder Mysticeti (baleen whales)
                                                            Family Balaenopteridae (roquals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Blue whale...................  Eastern North              6             4            0            0            0           10        1,496            <1
                                Pacific.
Fin whale....................  Northeast                  1             1            0            0         0.29         2.29        3,168            <1
                                Pacific.
                               CA/OR/WA.......           91            44            0            0         0.29       135.29        9,029             2
Humpback whale...............  Central North             47            68            0            0         0.29       115.29       10,103             1
                                Pacific.
                               CA/OR/WA.......           40            53            0            0         0.29        93.29        2,900             3
Minke whale..................  Alaska.........            1             1            0            0            0            2      \1\ 389            <1
                               CA/OR/WA.......          111           191            0            0         0.14       302.14          636            48
Sei whale....................  Eastern North             33            50            0            0            0           83          519            16
                                Pacific.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Family Eschrichtiidae
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gray whale...................  Eastern North             28            15            0            0         0.14        43.14       26,960            <1
                                Pacific.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Presented in the 2019 SARs or most recent SAR.
\1\ The 2018 final SAR (most recent SAR) for the Alaska stock of minke whales reports the stock abundance as unknown because only a portion of the
  stock's range has been surveyed. To be conservative, for this stock we report the smallest estimated abundance produced during recent surveys.

    The majority of takes by harassment of mysticetes in the NWTT Study 
Area are caused by anti-submarine warfare (ASW) activities in the 
Offshore portion of the Study Area. Anti-submarine activities include 
sources from the MFAS bin (which includes hull-mounted sonar) because 
they are high level, narrowband sources in the 1-10 kHz range, which 
intersect what is estimated to be the most sensitive area of hearing 
for mysticetes. They also are used in a large portion of exercises (see 
Tables 3 and 4). Most of the takes (90 percent) from the MF1 bin in the 
NWTT Study Area would result from received levels between 160 and 178 
dB SPL, while another 9 percent would result from exposure between 178 
and 184 dB SPL. For the remaining active sonar bin types, the 
percentages are as follows: LF4 = 97 percent between 124 and 142 dB 
SPL, MF4 = 95 percent between 136 and 148 dB SPL, MF5 = 97 percent 
between 112 and 142 dB SPL, and HF4 = 91 percent between 100 and 154 dB 
SPL. For mysticetes, explosive training activities do not result in any 
take. Explosive testing activities result in a small number of takes by 
Level B harassment by behavioral disturbance (0-6 per stock) and TTS 
takes (0-2 per stock). Based on this information, the majority of the 
Level B harassment by behavioral disturbance is expected to be of 
moderate and sometimes lower severity and of a relatively shorter 
duration. As noted above, no PTS or tissue damage from training and 
testing activities is anticipated or authorized for any species or 
stock.
    Research and observations show that if mysticetes are exposed to 
sonar or other active acoustic sources they may react in a number of 
ways depending on the characteristics of the sound source, their 
experience with the sound source, and whether they are migrating or on 
seasonal feeding or breeding grounds. Behavioral reactions may include 
alerting, breaking off feeding dives and surfacing, diving or swimming 
away, or no response at all (DOD, 2017; Nowacek, 2007; Richardson, 
1995; Southall et al., 2007). Overall, mysticetes have been observed to 
be more reactive to acoustic disturbance when a noise source is located 
directly on their migration route. Mysticetes disturbed while migrating 
could pause their migration or route around the disturbance, while 
males en route to breeding grounds have been shown to be less 
responsive to disturbances. Although some may pause temporarily, they 
will resume migration shortly after the exposure ends. Animals 
disturbed while engaged in other activities such as feeding or 
reproductive behaviors may be more likely to ignore or tolerate the 
disturbance and continue their natural behavior patterns.
    Alternately, adult female mysticetes with calves may be more 
responsive to stressors. An increase in the disturbance level from 
noise-generating human activities (such as sonar or explosives) may 
increase the risk of mother-calf pair separation (reducing the time 
available for suckling) or require that louder contact calls are made 
which, in turn, increases the possibility of detection. In either case, 
increased ambient noise could have negative consequences for calf 
fitness (Cartwright and Sullivan 2009; Craig et al., 2014). However, 
given the low number of

[[Page 72439]]

predicted mysticete exposures and the absence of known calving areas, 
exposure of younger, more vulnerable calves is considered to be 
unlikely in the NWTT Study Area.
    As noted in the Potential Effects of Specified Activities on Marine 
Mammals and Their Habitat section of the proposed rule, while there are 
multiple examples from behavioral response studies of odontocetes 
ceasing their feeding dives when exposed to sonar pulses at certain 
levels, alternately, blue whales (mysticetes) were less likely to show 
a visible response to sonar exposures at certain levels when feeding 
than when traveling. However, Goldbogen et al. (2013) indicated some 
horizontal displacement of deep foraging blue whales in response to 
simulated MFAS. Southall et al. (2019b) observed that after exposure to 
simulated and operational mid-frequency active sonar, more than 50 
percent of blue whales in deep-diving states responded to the sonar, 
while no behavioral response was observed in shallow-feeding blue 
whales. Southall et al. (2019b) noted that the behavioral responses 
they observed were generally brief, of low to moderate severity, and 
highly dependent on exposure context (behavioral state, source-to-whale 
horizontal range, and prey availability). Most Level B harassment by 
behavioral disturbance of mysticetes is likely to be short-term and of 
low to sometimes moderate severity, with no anticipated effect on 
reproduction or survival.
    Richardson et al. (1995) noted that avoidance (temporary 
displacement of an individual from an area) reactions are the most 
obvious manifestations of disturbance in marine mammals. Avoidance is 
qualitatively different from the startle or flight response, but also 
differs in the magnitude of the response (i.e., directed movement, rate 
of travel, etc.). Oftentimes avoidance is temporary, and animals return 
to the area once the noise has ceased. Some mysticetes may avoid larger 
activities as they move through an area, although the Navy's activities 
do not typically use the same training locations day-after-day during 
multi-day activities, except periodically in instrumented ranges. 
Therefore, displaced animals could return quickly after a large 
activity is completed. In the ocean, the use of Navy sonar and other 
active acoustic sources is transient and is unlikely to expose the same 
population of animals repeatedly over a short period of time, 
especially given the broader-scale movements of mysticetes.
    The implementation of procedural mitigation and the sightability of 
mysticetes (especially given their large size) further reduces the 
potential for a significant behavioral reaction or a threshold shift to 
occur (i.e., shutdowns are expected to be successfully implemented), 
which is reflected in the amount and type of incidental take that is 
anticipated to occur and authorized.
    As noted previously, when an animal incurs a threshold shift, it 
occurs in the frequency from that of the source up to one octave above. 
This means that the vast majority of threshold shifts caused by Navy 
sonar sources will typically occur in the range of 2-20 kHz (from the 
1-10 kHz MF1 bin, though in a specific narrow band within this range as 
the sources are narrowband), and if resulting from hull-mounted sonar, 
will be in the range of 3.5-7 kHz. The majority of mysticete 
vocalizations occur in frequencies below 1 kHz, which means that TTS 
incurred by mysticetes will not interfere with conspecific 
communication. Additionally, many of the other critical sounds that 
serve as cues for navigation and prey (e.g., waves, fish, 
invertebrates) occur below a few kHz, which means that detection of 
these signals will not be inhibited by most threshold shift either. 
When we look in ocean areas where the Navy has been intensively 
training and testing with sonar and other active acoustic sources for 
decades, there is no data suggesting any long-term consequences to 
reproduction or survival rates of mysticetes from exposure to sonar and 
other active acoustic sources.
    All the mysticete species discussed in this section will benefit 
from the procedural mitigation measures described earlier in the 
Mitigation Measures section. Additionally, the Navy will limit 
activities and employ other measures in mitigation areas that will 
avoid or reduce impacts to mysticetes utilizing those areas. Where 
these mitigation areas are designed to mitigate impacts to particular 
species or stocks (gray whales and humpback whales), they are discussed 
in detail below. Below we compile and summarize the information that 
supports our determination that the Navy's activities will not 
adversely affect any species or stock through effects on annual rates 
of recruitment or survival for any of the affected mysticete stocks.
Blue Whale (Eastern North Pacific Stock)
    Blue whales are listed as endangered under the ESA throughout their 
range, but there is no ESA designated critical habitat or biologically 
important area identified for this species in the NWTT Study Area. The 
SAR identifies this stock as ``stable.'' We further note that this 
stock was originally listed under the ESA as a result of the impacts 
from commercial whaling, which is no longer affecting the species. Blue 
whales are anticipated to be present in summer and winter months and 
only in the Offshore Area of the Study Area. No mortality from either 
explosives or vessel strike and no Level A harassment is anticipated or 
authorized.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance is less than 1 percent. Given the range 
of blue whales, this information indicates that only a very small 
portion of individuals in the stock are likely impacted and repeated 
exposures of individuals are not anticipated (i.e., individuals are not 
expected to be taken on more than one day within a year). Regarding the 
severity of those individual takes by Level B harassment by behavioral 
disturbance, we have explained that the duration of any exposure is 
expected to be between minutes and hours (i.e., relatively short) and 
the received sound levels largely below 172 dB with a small portion up 
to 184 dB (i.e., of a moderate or sometimes lower level). Regarding the 
severity of TTS takes, we have explained that they are expected to be 
low-level, of short duration, and mostly not in a frequency band that 
would be expected to interfere with blue whale communication or other 
important low-frequency cues and that the associated lost opportunities 
and capabilities are not at a level that will impact reproduction or 
survival.
    Altogether, although the species is listed as endangered under the 
ESA, this population is stable, only a very small portion of the stock 
is anticipated to be impacted, and any individual blue whale is likely 
to be disturbed at a low-moderate level. No mortality and no Level A 
harassment is anticipated or authorized. The low magnitude and 
moderate-lower severity of harassment effects is not expected to result 
in impacts on the reproduction or survival of any individuals, let 
alone have impacts on annual rates of recruitment or survival. For 
these reasons, we have determined, in consideration of all of the 
effects of the Navy's activities combined, that the authorized take 
will have a negligible impact on the Eastern North Pacific stock of 
blue whales.
Fin Whale (Northeast Pacific Stock and California/Oregon/Washington 
Stock)
    Fin whales are listed as endangered under the ESA throughout their 
range,

[[Page 72440]]

but no ESA designated critical habitat or biologically important areas 
are identified for this species in the NWTT Study Area. The SAR 
identifies these stocks as ``increasing.'' NMFS is authorizing two 
mortalities of fin whales over the seven years covered by this rule, 
but because it is not possible to determine from which stock these 
potential takes would occur, that is 0.29 mortality annually for each 
stock. The addition of this 0.29 annual mortality still leaves the 
total annual human-caused mortality well under residual PBR (37.2 for 
the CA/OR/WA stock and 4.7 for the Northeast Pacific stock) and below 
the insignificance threshold for both stocks. No mortality from 
explosives and no Level A harassment is anticipated or authorized.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance is less than 1 percent for the Northeast 
Pacific stock and 1.5 percent for the CA/OR/WA stock. This information 
indicates that only a very small portion of individuals in each stock 
are likely impacted and repeated exposures of individuals are not 
anticipated (i.e., individuals are not expected to be taken on more 
than one day within a year). Regarding the severity of those individual 
takes by Level B harassment by behavioral disturbance, the duration of 
any exposure is expected to be between minutes and hours (i.e., 
relatively short) and the received sound levels largely below 172 dB 
with a small portion up to 184 dB (i.e., of a moderate or sometimes 
lower level). Regarding the severity of TTS takes, they are expected to 
be low-level, of short duration, and mostly not in a frequency band 
that would be expected to interfere with fin whale communication or 
other important low-frequency cues--and the associated lost 
opportunities and capabilities are not at a level that will impact 
reproduction or survival.
    Altogether, although the species is listed as endangered under the 
ESA, these populations are increasing, only a very small portion of 
each stock is anticipated to be impacted, and any individual fin whale 
is likely to be disturbed at a low-moderate level. No Level A 
harassment is anticipated or authorized. This low magnitude and 
moderate-lower severity of harassment effects is not expected to result 
in impacts on individual reproduction or survival for any individuals, 
nor are these harassment takes combined with the authorized mortality 
expected to adversely affect these stocks through impacts on annual 
rates of recruitment or survival. For these reasons, we have 
determined, in consideration of all of the effects of the Navy's 
activities combined, that the authorized take will have a negligible 
impact on both the Northeast Pacific and CA/OR/WA stocks of fin whales.
Humpback Whale (Central North Pacific Stock)
    The Central North Pacific stock of humpback whales consists of 
winter/spring humpback whale populations of the Hawaiian Islands which 
migrate primarily to foraging habitat in northern British Columbia/
Southeast Alaska, the Gulf of Alaska, and the Bering Sea/Aleutian 
Islands (Muto et al. 2019). Three Feeding Area biologically important 
areas for humpback whales overlap with the NWTT Study Area: Northern 
Washington Feeding Area for humpback whales (May-November); Stonewall 
and Heceta Bank Feeding Area for humpback whales (May-November); and 
Point St. George Feeding Area for humpback whales (July-November) 
(Calambokidis et al., 2015). The Marine Species Coastal, Olympic Coast 
National Marine Sanctuary, Stonewall and Heceta Bank Humpback Whale, 
and Point St. George Humpback Whale Mitigation Areas overlap with these 
important foraging areas. The Marine Species Coastal Mitigation Area 50 
nmi from shore zone includes the entirety of all three BIAs. The 
Stonewall and Heceta Bank Humpback Whale Mitigation Area includes the 
entire Stonewall and Heceta Bank Feeding Area for humpback whales. The 
Point St. George Humpback Whale Mitigation Area and the 20 nmi from 
shore zone in the Marine Species Coastal Mitigation Area both include 
the entire Point St. George Feeding Area for humpback whales. 
Additionally, the new Juan de Fuca Eddy Marine Species Coastal 
Mitigation area will also benefit humpback whale feeding. The full 
extent of the Juan de Fuca Eddy is not incorporated into the Northern 
Washington humpback whale biologically important feeding area because 
the development of biologically important areas was restricted to U.S. 
waters only. Therefore, the Northern Washington biologically important 
humpback whale feeding area extends northward to the boundary of the 
U.S. Exclusive Economic Zone (Calambokidis et al., 2015; Ferguson et 
al., 2015a; Ferguson et al., 2015b). However, humpback whale 
aggregations feed across this political boundary in the nutrient rich 
waters throughout the Juan de Fuca Eddy from May to November. 
Therefore, waters within the Juan de Fuca Eddy between the Northern 
Washington humpback whale biologically important area and the northern 
boundary of the NWTT Offshore Area are included in the Juan de Fuca 
Eddy Marine Species Mitigation Area. The mitigation measures 
implemented in each of these areas, including but not limited to, no 
MF1 MFAS use seasonally or limited MFAS use year round, no explosive 
training, and no explosive testing or restrictions on explosive testing 
(see details of all mitigation measures for each area in the Mitigation 
Measures section), will reduce the severity of impacts to humpback 
whales by reducing interference in feeding that could result in lost 
feeding opportunities or necessitate additional energy expenditure to 
find other good opportunities.
    The SAR identifies this stock as ``increasing'' and the associated 
Hawaii DPS is not listed as endangered or threatened under the ESA. No 
mortality from explosives and no Level A harassment is anticipated or 
authorized. NMFS is authorizing two mortalities of humpback whales over 
the seven years covered by this rule, but because it is not possible to 
determine from which stock these potential takes would occur, that is 
0.29 mortality annually for both this stock and the CA/OR/WA stock 
(discussed separately below). The addition of this 0.29 annual 
mortality still leaves the total annual human-caused mortality well 
under both the insignificance threshold and residual PBR (57.7).
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated instances of take 
compared to the abundance is 1 percent. This information and the far-
ranging nature of the stock structure indicates that only a very small 
portion of the stock is likely impacted and repeated exposures of 
individuals are not anticipated (i.e., individuals are not expected to 
be taken on more than one day within a year). Regarding the severity of 
those individual takes by Level B harassment by behavioral disturbance, 
we have explained that the duration of any exposure is expected to be 
between minutes and hours (i.e., relatively short) and the received 
sound levels largely below 172 dB with a small portion up to 184 dB 
(i.e., of a moderate or sometimes lower level). Regarding the severity 
of TTS takes, they are expected to be low-level, of short duration, and 
mostly not in a frequency band that would be expected to interfere with 
humpback whale communication or other important low-frequency cues, and 
that the associated lost

[[Page 72441]]

opportunities and capabilities are not at a level that will impact 
reproduction or survival.
    Altogether, this population is increasing and the associated DPS is 
not listed as endangered or threatened under the ESA. Only a very small 
portion of the stock is anticipated to be impacted and any individual 
humpback whale is likely to be disturbed at a low-moderate level. No 
Level A harassment is anticipated or authorized. This low magnitude and 
moderate-lower severity of harassment effects is not expected to result 
in impacts on individual reproduction or survival, nor are these 
harassment takes combined with the authorized mortality expected to 
adversely affect this stock through effects on annual rates of 
recruitment or survival. For these reasons, we have determined, in 
consideration of all of the effects of the Navy's activities combined, 
that the authorized take will have a negligible impact on the Central 
North Pacific stock of humpback whales.
Humpback Whale (California/Oregon/Washington Stock)
    The CA/OR/WA stock of humpback whales includes individuals from 
three ESA DPSs: Central America (endangered), Mexico (threatened), and 
Hawaii (not listed). There is no ESA-designated critical habitat for 
humpback whales, however NMFS has proposed to designate critical 
habitat for humpback whales (84 FR 54354; October 9, 2019). Three 
Feeding Area biologically important areas for humpback whales overlap 
with the NWTT Study Area: Northern Washington Feeding Area for humpback 
whales (May-November); Stonewall and Heceta Bank Feeding Area for 
humpback whales (May-November); and Point St. George Feeding Area for 
humpback whales (July-November) (Calambokidis et al., 2015). The Marine 
Species Coastal, Olympic Coast National Marine Sanctuary, Stonewall and 
Heceta Bank Humpback Whale, and Point St. George Humpback Whale 
Mitigation Areas overlap with these important foraging areas. The 
Marine Species Coastal Mitigation Area 50 nmi from shore zone includes 
the entirety of all three BIAs. The Stonewall and Heceta Bank Humpback 
Whale Mitigation Area includes the entire Stonewall and Heceta Bank 
Feeding Area for humpback whales. The Point St. George Humpback Whale 
Mitigation Area and the 20 nmi from shore zone in the Marine Species 
Coastal Mitigation Area both include the entire Point St. George 
Feeding Area for humpback whales. Additionally, the new Juan de Fuca 
Eddy Marine Species Coastal Mitigation area will also benefit humpback 
whale feeding. The full extent of the Juan de Fuca Eddy is not 
incorporated into the Northern Washington humpback whale biologically 
important feeding area because the development of biologically 
important areas was restricted to U.S. waters only. Therefore, the 
Northern Washington biologically important humpback whale feeding area 
extends northward to the boundary of the U.S. Exclusive Economic Zone 
(Calambokidis et al., 2015; Ferguson et al., 2015a; Ferguson et al., 
2015b). However, humpback whale aggregations feed across this political 
boundary in the nutrient rich waters throughout the Juan de Fuca Eddy 
from May to November. Therefore, waters within the Juan de Fuca Eddy 
between the Northern Washington humpback whale biologically important 
area and the northern boundary of the NWTT Offshore Area are included 
in the Juan de Fuca Eddy Marine Species Mitigation Area. The mitigation 
measures implemented in each of these areas, including but not limited 
to, no MF1 MFAS use seasonally or limited MFAS use year round, no 
explosive training, and no explosive testing or restrictions on 
explosive testing (see details of all mitigation measures for each area 
in the Mitigation Measures section), will reduce the severity of 
impacts to humpback whales by reducing interference in feeding that 
could result in lost feeding opportunities or necessitate additional 
energy expenditure to find other good opportunities.
    The SAR identifies this stock as stable (having shown a long-term 
increase from 1990 and then leveling off between 2008 and 2014). NMFS 
is authorizing two mortalities over the seven years covered by this 
rule, or 0.29 mortality annually. With the addition of this 0.29 annual 
mortality, the total annual human-caused mortality exceeds residual PBR 
by 9.1. However, as described in more detail in the Serious Injury or 
Mortality subsection, when total human-caused mortality exceeds PBR, we 
consider whether the incremental addition of a small amount of 
mortality from the specified activity may still result in a negligible 
impact, in part by identifying whether it is less than 10 percent of 
PBR, which is 3.3. In this case, the authorized mortality is well below 
10 percent of PBR (less than one percent, in fact) and management 
measures are in place to reduce mortality from other sources. More 
importantly, as described above in the Serious Injury or Mortality 
section, the authorized mortality of 0.29 will not delay the time to 
recovery by more than 1 percent. Given these factors, the incremental 
addition of two mortalities over the course of the seven-year Navy rule 
is not expected to, alone (i.e., in the absence of any other take and 
barring any other unusual circumstances), lead to adverse impacts on 
the stock through effects on annual rates of recruitment or survival. 
No mortality from explosives and no Level A harassment is anticipated 
or authorized.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance is 3 percent (Table 52). Given the range 
of humpback whales, this information suggests that only a small portion 
of individuals in the stock are likely impacted and repeated exposures 
of individuals are not anticipated (i.e., individuals are not expected 
to be taken on more than one day within a year). Regarding the severity 
of those individual takes by Level B harassment by behavioral 
disturbance, we have explained that the duration of any exposure is 
expected to be between minutes and hours (i.e., relatively short) and 
the received sound levels largely below 172 dB with a small portion up 
to 184 dB (i.e., of a moderate or sometimes lower level). Regarding the 
severity of TTS takes, they are expected to be low-level, of short 
duration, and mostly not in a frequency band that would be expected to 
interfere with humpback whale communication or other important low-
frequency cues. Therefore, the associated lost opportunities and 
capabilities are not at a level that will impact reproduction or 
survival.
    Altogether, this population is stable and even though two of the 
three associated DPSs are listed as endangered or threatened under the 
ESA, only a small portion of the stock is anticipated to be impacted, 
and any individual humpback whale is likely to be disturbed at a low-
moderate level. No Level A harassment is anticipated or authorized. 
This low magnitude and moderate-lower severity of harassment effects is 
not expected to result in impacts on the reproduction or survival of 
any individuals and, therefore, when combined with the authorized 
mortality (which our earlier analysis indicated will not, alone, have 
more than a negligible impact on this stock of humpback whales), is not 
expected to adversely affect this stock through impacts on annual rates 
of recruitment or survival. For these reasons, we have determined, in 
consideration of all of the effects of the Navy's activities

[[Page 72442]]

combined, that the authorized take will have a negligible impact on the 
CA/OR/WA stock of humpback whales.
Minke Whale (Alaska and California/Oregon/Washington Stocks)
    The status of these stocks is unknown and the species is not listed 
under the ESA. No biologically important areas have been identified for 
this species in the NWTT Study Area. NMFS is authorizing one mortality 
over the seven years covered by this rule, or 0.14 mortality annually, 
for the CA/OR/WA stock, and no mortality is anticipated or authorized 
for the Alaska stock. The addition of this 0.14 annual mortality still 
leaves the total annual human-caused mortality well under the residual 
PBR (2.2) and below the insignificance threshold. No mortality from 
explosives and no Level A harassment is anticipated or authorized for 
either stock.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance is less than 1 percent for the Alaska 
stock (based on, to be conservative, the smallest available provisional 
estimate in the SAR, which is derived from surveys that cover only a 
portion of the stock's range) and 47.5 percent for the CA/OR/WA stock. 
Given the range of minke whales, this information indicates that only a 
very small portion of individuals in the Alaska stock are likely to be 
impacted and repeated exposures of individuals are not anticipated 
(i.e., individuals are not expected to be taken on more than one day 
within a year). For the CA/OR/WA stock, fewer than half of the 
individuals in the stock will likely be taken, with those individuals 
disturbed on likely one, but not more than a few non-sequential days 
within a year. Regarding the severity of those individual takes by 
Level B harassment by behavioral disturbance, we have explained that 
the duration of any exposure is expected to be between minutes and 
hours (i.e., relatively short) and the received sound levels largely 
below 172 dB with a small portion up to 184 dB (i.e., of a moderate or 
sometimes lower level). Regarding the severity of TTS takes, they are 
expected to be low-level, of short duration, and mostly not in a 
frequency band that would be expected to interfere with minke whale 
communication or other important low-frequency cues--and the associated 
lost opportunities and capabilities are not at a level that will impact 
reproduction or survival.
    Altogether, although the status of the stocks is unknown, the 
species is not listed under the ESA as endangered or threatened, only a 
smaller portion of these stocks is anticipated to be impacted, and any 
individual minke whale is likely to be disturbed at a low-moderate 
level. No Level A harassment is anticipated or authorized. This low 
magnitude and moderate-lower severity of harassment effects is not 
expected to result in impacts on individual reproduction or survival 
for either stock, nor are these harassment takes combined with the 
authorized mortality expected to adversely affect the CA/OR/WA stock 
through effects on annual rates of recruitment or survival. For these 
reasons, we have determined, in consideration of all of the effects of 
the Navy's activities combined, that the authorized take will have a 
negligible impact on the Alaska and CA/OR/WA stocks of minke whales.
Sei Whale (Eastern North Pacific Stock)
    The status of this stock is unknown, however sei whales are listed 
as endangered under the ESA throughout their range. There is no ESA 
designated critical habitat or biologically important areas identified 
for this species in the NWTT Study Area. No mortality from either 
explosives or vessel strikes and no Level A harassment is anticipated 
or authorized.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance is 16 percent (Table 52). This 
information and the large range of sei whales suggests that only a 
small portion of individuals in the stock are likely impacted and 
repeated exposures of individuals are not anticipated (i.e., 
individuals are not expected to be taken on more than one day within a 
year). Regarding the severity of those individual takes by Level B 
harassment by behavioral disturbance, we have explained that the 
duration of any exposure is expected to be between minutes and hours 
(i.e., relatively short) and the received sound levels largely below 
172 dB with a small portion up to 184 dB (i.e., of a moderate or 
sometimes lower level). Regarding the severity of TTS takes, they are 
expected to be low-level, of short duration, and mostly not in a 
frequency band that would be expected to interfere with sei whale 
communication or other important low-frequency cues. Therefore the 
associated lost opportunities and capabilities are not at a level that 
will impact reproduction or survival.
    Altogether, the status of the stock is unknown and the species is 
listed as endangered, but only a small portion of the stock is 
anticipated to be impacted and any individual sei whale is likely to be 
disturbed at a low-moderate level. No mortality and no Level A 
harassment is anticipated or authorized. This low magnitude and 
moderate-lower severity of harassment effects is not expected to result 
in impacts on the reproduction or survival of any individuals, let 
alone have impacts on annual rates of recruitment or survival. 
Therefore, the total take will not adversely affect this stock through 
impacts on annual rates of recruitment or survival. For these reasons, 
we have determined, in consideration of all of the effects of the 
Navy's activities combined, that the authorized take will have a 
negligible impact on the Eastern North Pacific stock of sei whales.
Gray Whale (Eastern North Pacific Stock)
    The SAR identifies this stock as ``increasing'' and the associated 
DPS is not listed under the ESA. The NWTT Study Area overlaps with the 
offshore Northwest Feeding Area for gray whales and the Northern Puget 
Sound Feeding Area for gray whales, both identified as biologically 
important areas. In addition, a portion of the Northwest coast of 
Washington, approximately from Pacific Beach (WA) and extending north 
to the Strait of Juan de Fuca, overlaps with the gray whale migration 
corridor biologically important areas (Northbound and Southbound). The 
Marine Species Coastal, Olympic Coast National Marine Sanctuary, 
Stonewall and Heceta Bank Humpback Whale, Point St. George Humpback 
Whale, Puget Sound and Strait of Juan de Fuca, and Northern Puget Sound 
Gray Whale Mitigation Areas overlap with these important foraging and 
migration areas. The Marine Species Coastal Mitigation Area (all 
distances--50 nmi, 20 nmi, and 12 nmi from shore) include the entire 
offshore Northwest Feeding Area for gray whales as well as the 
Northbound Phase A, Northbound Phase B, and Southbound gray whale 
migration corridor BIAs. The Olympic Coast National Marine Sanctuary 
Mitigation Area overlaps with each of these BIAs by 96-100 percent. The 
Stonewall and Heceta Bank Humpback Whale Mitigation Area and the Point 
St. George Humpback Whale Mitigation Area overlap minimally with the 
gray whale potential presence migration BIA (5 percent overlap or 
less). The Puget Sound and Strait of Juan de Fuca Mitigation Area and 
the Northern Puget Sound Gray Whale Mitigation Area both include the 
entire Northern Puget Sound Feeding Area for gray whales. The 
mitigation measures implemented

[[Page 72443]]

in each of these areas, including but not limited to, no MF1 MFAS use 
seasonally or limited MFAS use year round, no explosive training, and 
no explosive testing or restrictions on explosive testing (see details 
of all mitigation measures for each area in the Mitigation Measures 
section), will reduce the severity of impacts to gray whales by 
reducing interference in feeding and migration that could result in 
lost feeding opportunities or necessitate additional energy expenditure 
to find other good foraging opportunities or move migration routes.
    NMFS is authorizing one mortality over the seven years covered by 
this rule, or 0.14 mortality annually. The addition of this 0.14 annual 
mortality still leaves the total annual human-caused mortality well 
under both the insignificance threshold and residual PBR (661.6). No 
mortality from explosives and no Level A harassment is anticipated or 
authorized.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance is less than 1 percent. This information 
indicates that only a very small portion of individuals in the stock 
are likely to be impacted and repeated exposures of individuals are not 
anticipated (i.e., individuals are not expected to be taken on more 
than one day within a year). Regarding the severity of those individual 
takes by Level B harassment by behavioral disturbance, we have 
explained that the duration of any exposure is expected to be between 
minutes and hours (i.e., relatively short) and the received sound 
levels largely below 172 dB with a small portion up to 184 dB (i.e., of 
a moderate or sometimes lower level). Regarding the severity of TTS 
takes, they are expected to be low-level, of short duration, and mostly 
not in a frequency band that would be expected to interfere with gray 
whale communication or other important low-frequency cues and that the 
associated lost opportunities and capabilities are not at a level that 
will impact reproduction or survival.
    Altogether, while we have considered the impacts of the gray whale 
UME, this population of gray whales is not endangered or threatened 
under the ESA and the stock is increasing. No Level A harassment is 
anticipated or authorized. Only a very small portion of the stock is 
anticipated to be impacted by Level B harassment and any individual 
gray whale is likely to be disturbed at a low-moderate level. This low 
magnitude and moderate-lower severity of harassment effects is not 
expected to result in impacts to reproduction or survival for any 
individuals, nor are these harassment takes combined with the 
authorized mortality of one whale over the seven-year period expected 
to adversely affect this stock through impacts on annual rates of 
recruitment or survival. For these reasons, we have determined, in 
consideration of all of the effects of the Navy's activities combined, 
that the authorized take will have a negligible impact on the Eastern 
North Pacific stock of gray whales.
Odontocetes
    This section builds on the broader discussion above and brings 
together the discussion of the different types and amounts of take that 
different species and stocks could potentially or will likely incur, 
the applicable mitigation, and the status of the species and stock to 
support the negligible impact determinations for each species or stock. 
We have described (above in the General Negligible Impact Analysis 
section) the unlikelihood of any masking having effects that will 
impact the reproduction or survival of any of the individual marine 
mammals affected by the Navy's activities. We have also described in 
the Potential Effects of Specified Activities on Marine Mammals and 
their Habitat section of the proposed rule that the specified 
activities would not have adverse or long-term impacts on marine mammal 
habitat, and therefore the unlikelihood of any habitat impacts 
affecting the reproduction or survival of any individual marine mammals 
affected by the Navy's activities. No new information has been received 
that affects this analysis and conclusion, although mitigation measures 
have been added that will further reduce impacts to Southern Resident 
killer whales, other odontocetes, and their habitat. For odontocetes, 
there is no anticipated M/SI or tissue damage from sonar or explosives 
for any species or stock. Here, we include information that applies to 
all of the odontocete species, which are then further divided and 
discussed in more detail in the following subsections: Sperm whales, 
dwarf sperm whales, and pygmy sperm whales; beaked whales; dolphins and 
small whales; and porpoises. These subsections include more specific 
information about the groups, as well as conclusions for each species 
or stock represented.
    The majority of takes by harassment of odontocetes in the NWTT 
Study Area are caused by sources from the MFAS bin (which includes 
hull-mounted sonar) because they are high level, typically narrowband 
sources at a frequency (in the 1-10 kHz range) that overlaps a more 
sensitive portion (though not the most sensitive) of the MF hearing 
range and they are used in a large portion of exercises (see Tables 3 
and 4). For odontocetes other than beaked whales and porpoises (for 
which these percentages are indicated separately in those sections), 
most of the takes (96 percent) from the MF1 bin in the NWTT Study Area 
would result from received levels between 160 and 172 dB SPL. For the 
remaining active sonar bin types, the percentages are as follows: LF4 = 
99 percent between 124 and 154 dB SPL, MF4 = 99 percent between 136 and 
166 dB SPL, MF5 = 98 percent between 112 and 148 dB SPL, and HF4 = 95 
percent between 100 and 160 dB SPL. Based on this information, the 
majority of the takes by Level B harassment by behavioral disturbance 
are expected to be low to sometimes moderate in nature, but still of a 
generally shorter duration.
    For all odontocetes, takes from explosives (Level B harassment by 
behavioral disturbance, TTS, or PTS) comprise a very small fraction 
(and low number) of those caused by exposure to active sonar. For the 
following odontocetes, zero takes from explosives are expected to 
occur: Common bottlenose dolphins, killer whales, short-beaked common 
dolphins, short-finned pilot whales, the Alaska stock of Dall's 
porpoises, Southeast Alaska stock of harbor porpoises, sperm whales, 
Baird's beaked whale, Cuvier's beaked whale, and Mesoplodon species. 
For Level B harassment by behavioral disturbance from explosives, with 
the exception of porpoises, one take is anticipated for the remaining 
species/stocks. For the CA/OR/WA stock of Dall's porpoise and the 
remaining three harbor porpoise stocks, 1-91 takes by Level B 
harassment by behavioral disturbance from explosives are anticipated. 
Similarly the instances of TTS and PTS expected to occur from 
explosives for all remaining species/stocks, with the exception of 
porpoises, are anticipated to be low (1-3 for TTS and 1 for PTS). 
Because of the lower TTS and PTS thresholds for HF odontocetes, for the 
CA/OR/WA stock of Dall's porpoise and the remaining three harbor 
porpoise stocks, TTS takes range from 61-214 and PTS takes range from 
27-86.
    Because the majority of harassment takes of odontocetes result from 
the sources in the MFAS bin, the vast majority of threshold shift would 
occur upon receipt of a single frequency within the 1-10 kHz range and, 
therefore, the vast majority of threshold shift caused by Navy sonar 
sources

[[Page 72444]]

would be at a single frequency within the range of 2-20 kHz. The 
frequency range within which any of the anticipated narrowband 
threshold shift would occur would fall directly within the range of 
most odontocete vocalizations (2-20 kHz). For example, the most 
commonly used hull-mounted sonar has a frequency around 3.5 kHz, and 
any associated threshold shift would be expected to be at around 7 kHz. 
However, odontocete vocalizations typically span a much wider range 
than this, and alternately, threshold shift from active sonar will 
often be in a narrower band (reflecting the narrower band source that 
caused it), which means that TTS incurred by odontocetes would 
typically only interfere with communication within a portion of their 
range (if it occurred during a time when communication with 
conspecifics was occurring) and, as discussed earlier, it would only be 
expected to be of a short duration and relatively small degree. 
Odontocete echolocation occurs predominantly at frequencies 
significantly higher than 20 kHz, though there may be some small 
overlap at the lower part of their echolocating range for some species, 
which means that there is little likelihood that threshold shift, 
either temporary or permanent, would interfere with feeding behaviors. 
Many of the other critical sounds that serve as cues for navigation and 
prey (e.g., waves, fish, invertebrates) occur below a few kHz, which 
means that detection of these signals will not be inhibited by most 
threshold shift either. The low number of takes by threshold shift that 
might be incurred by individuals exposed to explosives would likely be 
lower frequency (5 kHz or less) and spanning a wider frequency range, 
which could slightly lower an individual's sensitivity to navigational 
or prey cues, or a small portion of communication calls, for several 
minutes to hours (if temporary) or permanently. There is no reason to 
think that any of the individual odontocetes taken by TTS would incur 
these types of takes over more than one day, or over a few days at 
most, and therefore they are unlikely to incur impacts on reproduction 
or survival. The number of PTS takes from these sources are very low, 
and while spanning a wider frequency band, are still expected to be of 
a low degree (i.e., low amount of hearing sensitivity loss) and 
unlikely to affect reproduction or survival.
    The range of potential behavioral effects of sound exposure on 
marine mammals generally, and odontocetes specifically, has been 
discussed in detail previously. There are behavioral patterns that 
differentiate the likely impacts on odontocetes as compared to 
mysticetes. First, odontocetes echolocate to find prey, which means 
that they actively send out sounds to detect their prey. While there 
are many strategies for hunting, one common pattern, especially for 
deeper diving species, is many repeated deep dives within a bout, and 
multiple bouts within a day, to find and catch prey. As discussed 
above, studies demonstrate that odontocetes may cease their foraging 
dives in response to sound exposure. If enough foraging interruptions 
occur over multiple sequential days, and the individual either does not 
take in the necessary food, or must exert significant effort to find 
necessary food elsewhere, energy budget deficits can occur that could 
potentially result in impacts to reproductive success, such as 
increased cow/calf intervals (the time between successive calving). 
Second, while many mysticetes rely on seasonal migratory patterns that 
position them in a geographic location at a specific time of the year 
to take advantage of ephemeral large abundances of prey (i.e., 
invertebrates or small fish, which they eat by the thousands), 
odontocetes forage more homogeneously on one fish or squid at a time. 
Therefore, if odontocetes are interrupted while feeding, it is often 
possible to find more prey relatively nearby.
    All the Odontocete species discussed in this section will benefit 
from the procedural mitigation measures described earlier in the 
Mitigation Measures section. Additionally, the Navy will limit 
activities and employ other measures in mitigation areas that will 
avoid or reduce impacts to Odonticetes utilizing those areas, as 
discussed in more detail below.
Sperm Whale, Dwarf Sperm Whale, and Pygmy Sperm Whale
    This section builds on the broader odontocete discussion above and 
brings together the discussion of the different types and amounts of 
take that different species and stocks could potentially or will likely 
incur, any additional applicable mitigation, and the status of the 
species and stocks to support the negligible impact determinations for 
each species or stock. For sperm whales, there is no predicted PTS from 
sonar or explosives and no predicted tissue damage from explosives. For 
dwarf sperm whales and pygmy sperm whales (described as Kogia species 
for the reasons explained below) no mortality or tissue damage from 
sonar or explosives is anticipated or authorized and only one PTS take 
is predicted.
    In Table 53 below for sperm whales and Kogia species, we indicate 
the total annual numbers of take by mortality, Level A and Level B 
harassment, and a number indicating the instances of total take as a 
percentage of abundance.

Table 53--Annual Estimated Takes by Level B Harassment, Level A Harassment, and Mortality for Sperm Whales and Kogia spp. (Dwarf Sperm Whales, and Pygmy
                Sperm Whales) in the NWTT Study Area and Number Indicating the Instances of Total Take as a Percentage of Stock Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                 Instances of indicated types of incidental take  (not all takes
                                                   represent separate individuals, especially for disturbance)
                                               ------------------------------------------------------------------                             Instances
                                                    Level B harassment        Level A harassment                                Abundance     of total
           Species                  Stock      -----------------------------------------------------              Total takes  (NMFS SARs)     take as
                                                               TTS (may                               Mortality                     *        percentage
                                                 Behavioral  also include      PTS         Tissue                                           of abundance
                                                disturbance  disturbance)                  damage
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          Suborder Odontoceti (toothed whales)
                                                            Family Physeteridae (sperm whale)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale*.................  CA/OR/WA.......          834             5            0            0         0.14          839        1,997            42
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Family Kogiidae (sperm whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Kogia Species................  CA/OR/WA.......          365           517            2            0            0          884        4,111            22
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Presented in the 2019 SARs or most recent SAR.
Note: As indicated in Table 32 and Table 33, the Kogia Spp. take estimates were updated to reflect clarifications due to rounding errors in the proposed
  rule.


[[Page 72445]]

    As discussed above, the majority of takes by Level B harassment by 
behavioral disturbance of odontocetes, and thereby sperm whales and 
Kogia species, is expected to be in the form of low to occasionally 
moderate severity of a generally shorter duration. As discussed earlier 
in this section, we anticipate more severe effects from takes when 
animals are exposed to higher received levels or for longer durations. 
Occasional milder Level B harassment by behavioral disturbance, as is 
expected here, is unlikely to cause long-term consequences for either 
individual animals or populations, even if some smaller subset of the 
takes are in the form of a longer (several hours or a day) and more 
moderate response.
    We note that Kogia species (dwarf and pygmy sperm whales), as HF-
sensitive species, have a lower PTS threshold than all other groups and 
therefore are generally likely to experience larger amounts of TTS and 
PTS, and NMFS accordingly has evaluated and authorized higher numbers. 
Also, however, regarding PTS from sonar exposure, Kogia whales are 
still likely to avoid sound levels that would cause higher levels of 
TTS (greater than 20 dB) or PTS. Therefore, even though the number of 
TTS takes are higher than for other odontocetes, any PTS is expected to 
be at a lower level and for all of the reasons described above, TTS and 
PTS are not expected to impact reproduction or survival of any 
individual.
    Below we compile and summarize the information that supports our 
determination that the Navy's activities will not adversely affect 
sperm whales and pygmy and dwarf sperm whales through effects on annual 
rates of recruitment or survival.
Sperm Whale (California/Oregon/Washington Stock)
    The SAR identifies the CA/OR/WA stock of sperm whales as ``stable'' 
although the species is listed as endangered under the ESA. No critical 
habitat has been designated for sperm whales under the ESA and no 
biologically important areas have been identified for sperm whales in 
the NWTT Study Area. NMFS is authorizing one mortality for the CA/OR/WA 
stock of sperm whales over the seven years covered by this rule, or 
0.14 mortality annually. The addition of this 0.14 annual mortality 
still leaves the total human-caused mortality under residual PBR (1.8) 
and below the insignificance threshold. No mortality from explosives 
and no Level A harassment is anticipated or authorized.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance is 42 percent for sperm whales. Given 
the range of this stock (which extends the entire length of the U.S. 
West Coast, as well as beyond the U.S. EEZ boundary), this information 
indicates that notably fewer than half the individuals in the stock are 
likely to be taken annually and with those individuals disturbed on 
likely one, but not more than a few non-sequential days within a year. 
Additionally, while interrupted feeding bouts are a known response and 
concern for odontocetes, we also know that there are often viable 
alternative habitat options in the relative vicinity. Regarding the 
severity of those individual takes by Level B harassment by behavioral 
disturbance, we have explained that the duration of any exposure is 
expected to be between minutes and hours (i.e., relatively short) and 
the received sound levels largely below 172 dB (i.e., of a lower, to 
occasionally moderate, level and less likely to evoke a severe 
response). Regarding the severity of TTS takes, they are expected to be 
low-level, of short duration, and mostly not in a frequency band that 
would be expected to interfere with sperm whale communication or other 
important low-frequency cues. Therefore, the associated lost 
opportunities and capabilities are not at a level that will impact 
reproduction or survival.
    Altogether, this population is stable (even though the species is 
listed under the ESA), only a portion (notably less than half) of the 
stock is anticipated to be impacted, and any individual sperm whale is 
likely to be disturbed at a low-moderate level. No Level A harassment 
is anticipated or authorized. This low magnitude and low-moderate 
severity of harassment effects is not expected to result in impacts on 
the reproduction or survival for any individuals, nor are these 
harassment takes combined with the authorized mortality expected to 
adversely affect this stock through impacts on annual rates of 
recruitment or survival. For these reasons, we have determined, in 
consideration of all of the effects of the Navy's activities combined, 
that the authorized take will have a negligible impact on the CA/OR/WA 
stock of sperm whales.
Kogia Species (California/Oregon/Washington Stocks)
    The status of the CA/OR/WA stocks of pygmy and dwarf sperm whales 
(Kogia species) is unknown and neither are listed under the ESA. No 
biologically important areas have been identified for Kogia species in 
the NWTT Study Area. No mortality or Level A harassment from tissue 
damage are anticipated or authorized, and two PTS Level A harassment 
takes are expected and authorized.
    Due to their pelagic distribution, small size, and cryptic 
behavior, pygmy sperm whales and dwarf sperm whales (Kogia species) are 
rarely sighted during at-sea surveys and are difficult to distinguish 
between when visually observed in the field. Many of the relatively few 
observations of Kogia species off the U.S. West Coast were not 
identified to species. All at-sea sightings of Kogia species have been 
identified as pygmy sperm whales or Kogia species generally. Stranded 
dwarf sperm and pygmy sperm whales have been found on the U.S. West 
Coast, however dwarf sperm whale strandings are rare. NMFS SARs suggest 
that the majority of Kogia sighted off the U.S. West Coast were likely 
pygmy sperm whales. As such, the stock estimate in the NMFS SAR for 
pygmy sperm whales is the estimate derived for all Kogia species in the 
region (Barlow, 2016), and no separate abundance estimate can be 
determined for dwarf sperm whales, though some low number likely reside 
in the U.S. EEZ. Due to the lack of an abundance estimate it is not 
possible to predict the amount of Level A and Level B harassment take 
of dwarf sperm whales and therefore take estimates are identified as 
Kogia whales (including both pygmy and dwarf sperm whales). We assume 
only a small portion of those takes are likely to be dwarf sperm whales 
as the available information indicates that the density and abundance 
in the U.S. EEZ is low.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance is 21 percent. Given the range of these 
stocks (which extends the entire length of the West Coast, as well as 
beyond the U.S. EEZ boundary), this information indicates that only a 
small portion of the individuals in the stocks are likely to be 
impacted and repeated exposures of individuals are not anticipated 
(i.e., individuals are not expected to be taken on more than one day 
within a year). Additionally, while interrupted feeding bouts are a 
known response and concern for odontocetes, we also know that there are 
often viable alternative habitat options in the relative vicinity. 
Regarding the severity of those individual takes by Level B harassment 
by behavioral disturbance, we have explained that the duration of any 
exposure is expected to be between minutes and hours (i.e., relatively 
short) and the received sound levels largely below 172 dB (i.e., of a 
lower, to

[[Page 72446]]

occasionally moderate, level and less likely to evoke a severe 
response). Regarding the severity of TTS takes, they are expected to be 
low-level, of short duration, and mostly not in a frequency band that 
would be expected to interfere with dwarf or pygmy sperm whale 
communication or other important low-frequency cues. Therefore, the 
associated lost opportunities and capabilities are not at a level that 
will impact reproduction or survival. A small permanent loss of hearing 
sensitivity (PTS) may include some degree of energetic costs for 
compensating or may mean some small loss of opportunities or detection 
capabilities, but at the expected degree the estimated two Level A 
harassment takes by PTS are unlikely to impact behaviors, 
opportunities, or detection capabilities to a degree that will 
interfere with reproductive success or survival of the affected 
individuals, let alone affect annual rates of recruitment or survival 
for the stock.
    Altogether, although the status of the stocks is unknown, these 
species are not listed under the ESA as endangered or threatened, only 
a small portion of these stocks are anticipated to be impacted, and any 
individual Kogia whale is likely to be disturbed at a low-moderate 
level. This low magnitude and low-moderate severity of harassment 
effects is not expected to result in impacts on the reproduction or 
survival of any individuals, let alone have impacts on annual rates of 
recruitment or survival. Two individuals could be taken by PTS annually 
of likely low severity, the impact of which also is not expected to 
affect reproduction or survival, alone or in combination with the 
authorized Level B harassment. For these reasons, we have determined, 
in consideration of all of the effects of the Navy's activities 
combined, that the authorized take will have a negligible impact on the 
CA/OR/WA stocks of Kogia whales.
Beaked Whales
    This section builds on the broader odontocete discussion above 
(i.e., that information applies to beaked whales as well), and brings 
together the discussion of the different types and amounts of take that 
different beaked whale species and stocks will likely incur, any 
additional applicable mitigation, and the status of the species and 
stocks to support the negligible impact determinations for each species 
or stock. For beaked whales, there is no anticipated Level A harassment 
by PTS or tissue damage from sonar or explosives, and no mortality is 
anticipated or authorized.
    In Table 54 below for beaked whales, we indicate the total annual 
numbers of take by mortality, Level A and Level B harassment, and a 
number indicating the instances of total take as a percentage of 
abundance.

Table 54--Annual Estimated Takes by Level B Harassment, Level A Harassment, and Mortality for Beaked Whales in the NWTT Study Area and Number Indicating
                                             the Instances of Total Take as a Percentage of Stock Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                 Instances of indicated types of incidental take  (not all takes
                                                   represent separate individuals, especially for disturbance)
                                               ------------------------------------------------------------------                             Instances
                                                    Level B harassment        Level A harassment                                Abundance     of total
           Species                  Stock      -----------------------------------------------------              Total takes  (NMFS SARs)     take as
                                                               TTS (may                               Mortality                     *        percentage
                                                 Behavioral  also include      PTS         Tissue                                           of abundance
                                                disturbance  disturbance)                  damage
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          Suborder Odontoceti (toothed whales)
                                                            Family Ziphiidae (beaked whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baird's beaked whale.........  CA/OR/WA.......          976             0            0            0            0          976        2,697            36
Cuvier's beaked whale........  CA/OR/WA.......        2,535             4            0            0            0        2,539        3,274            78
Mesoplodont beaked whales....  CA/OR/WA.......        1,119             3            0            0            0        1,122        3,044            37
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Presented in the 2019 SARs or most recent SAR.

    This first paragraph provides specific information that is in lieu 
of the parallel information provided for odontocetes as a whole. The 
majority of takes by harassment of beaked whales in the NWTT Study Area 
are caused by sources from the MFAS bin (which includes hull-mounted 
sonar) because they are high level narrowband sources that fall within 
the 1-10 kHz range, which overlap a more sensitive portion (though not 
the most sensitive) of the MF hearing range. Also, of the sources 
expected to result in take, they are used in a large portion of 
exercises (see Tables 3 and 4). Most of the takes (95 percent) from the 
MF1 bin in the NWTT Study Area would result from received levels 
between 142 and 160 dB SPL. For the remaining active sonar bin types, 
the percentages are as follows: LF4 = 99 percent between 118 and 148 dB 
SPL, MF4 = 97 percent between 124 and 148 dB SPL, MF5 = 99 percent 
between 100 and 148 dB SPL, and HF4 = 97 percent between 100 and 154 dB 
SPL. Given the levels they are exposed to and their sensitivity, some 
responses would be of a lower severity, but many would likely be 
considered moderate, but still of generally short duration.
    Research has shown that beaked whales are especially sensitive to 
the presence of human activity (Pirotta et al., 2012; Tyack et al., 
2011) and therefore have been assigned a lower harassment threshold, 
with lower received levels resulting in a higher percentage of 
individuals being harassed and a more distant distance cutoff (50 km 
for high source level, 25 km for moderate source level).
    Beaked whales have been documented to exhibit avoidance of human 
activity or respond to vessel presence (Pirotta et al., 2012). Beaked 
whales were observed to react negatively to survey vessels or low 
altitude aircraft by quick diving and other avoidance maneuvers, and 
none were observed to approach vessels (Wursig et al., 1998). It has 
been speculated for some time that beaked whales might have unusual 
sensitivities to sonar sound due to their likelihood of stranding in 
conjunction with MFAS use, although few definitive causal relationships 
between MFAS use and strandings have been documented (see Potential 
Effects of Specified Activities on Marine Mammals and their Habitat 
section in the proposed rule). However, as described in the Estimated 
Take of Marine Mammals section of this final rule and further addressed 
in the response to Comment 19, NMFS neither

[[Page 72447]]

anticipates nor authorizes the mortality of beaked whales (or other 
species or stocks) resulting from exposure to active sonar.
    Research and observations show that if beaked whales are exposed to 
sonar or other active acoustic sources, they may startle, break off 
feeding dives, and avoid the area of the sound source to levels of 157 
dB re: 1 [micro]Pa, or below (McCarthy et al., 2011). For example, 
after being exposed to 1-2 kHz upsweep naval sonar signals at a 
received SPL of 107 dB re 1 [mu]Pa, Northern bottlenose whales began 
moving in an unusually straight course, made a near 180[deg] turn away 
from the source, and performed the longest and deepest dive (94 min, 
2339 m) recorded for this species (Miller et al. 2015). Wensveen et al. 
(2019) also documented avoidance behaviors in Northern bottlenose 
whales exposed to 1-2 kHz tonal sonar signals with SPLs ranging between 
117-126 dB re: 1 [micro]Pa, including interrupted diving behaviors, 
elevated swim speeds, directed movements away from the sound source, 
and cessation of acoustic signals throughout exposure periods. Acoustic 
monitoring during actual sonar exercises revealed some beaked whales 
continuing to forage at levels up to 157 dB re: 1 [micro]Pa (Tyack et 
al., 2011). Stimpert et al. (2014) tagged a Baird's beaked whale, which 
was subsequently exposed to simulated MFAS. Changes in the animal's 
dive behavior and locomotion were observed when received level reached 
127 dB re: 1 [mu]Pa. However, Manzano-Roth et al. (2013) found that for 
beaked whale dives that continued to occur during MFAS activity, 
differences from normal dive profiles and click rates were not detected 
with estimated received levels up to 137 dB re: 1 [micro]Pa while the 
animals were at depth during their dives. In research done at the 
Navy's fixed tracking range in the Bahamas, animals were observed to 
leave the immediate area of the anti-submarine warfare training 
exercise (avoiding the sonar acoustic footprint at a distance where the 
received level was ``around 140 dB SPL'', according to Tyack et al. 
(2011)), but return within a few days after the event ended (Claridge 
and Durban, 2009; McCarthy et al., 2011; Moretti et al., 2009, 2010; 
Tyack et al., 2010, 2011). Joyce et al. (2019) found that Blainville's 
beaked whales moved up to 68 km away from an Atlantic Undersea Test and 
Evaluation Center site and reduced time spent on deep dives after the 
onset of mid-frequency active sonar exposure; whales did not return to 
the site until 2-4 days after the exercises ended. Changes in acoustic 
activity have also been documented. For example, Blainville's beaked 
whales showed decreased group vocal periods after biannual multi-day 
Navy training activities (Henderson et al.2016). Tyack et al. (2011) 
report that, in reaction to sonar playbacks, most beaked whales stopped 
echolocating, made long slow ascent to the surface, and moved away from 
the sound. A similar behavioral response study conducted in Southern 
California waters during the 2010-2011 field season found that Cuvier's 
beaked whales exposed to MFAS displayed behavior ranging from initial 
orientation changes to avoidance responses characterized by energetic 
fluking and swimming away from the source (DeRuiter et al., 2013b). 
However, the authors did not detect similar responses to incidental 
exposure to distant naval sonar exercises at comparable received 
levels, indicating that context of the exposures (e.g., source 
proximity, controlled source ramp-up) may have been a significant 
factor. The study itself found the results inconclusive and meriting 
further investigation. Falcone et al. (2017) however, documented that 
Cuvier's beaked whales had longer dives and surface durations after 
exposure to mid-frequency active sonar, with the longer surface 
intervals contributing to a longer interval between deep dives, a proxy 
for foraging disruption in this species. Cuvier's beaked whale 
responses suggested particular sensitivity to sound exposure consistent 
with results for Blainville's beaked whale.
    Populations of beaked whales and other odontocetes on the Bahamas 
and other Navy fixed ranges that have been operating for decades appear 
to be stable. Behavioral reactions (avoidance of the area of Navy 
activity) seem likely in most cases if beaked whales are exposed to 
anti-submarine sonar within a few tens of kilometers, especially for 
prolonged periods (a few hours or more) since this is one of the most 
sensitive marine mammal groups to anthropogenic sound of any species or 
group studied to date and research indicates beaked whales will leave 
an area where anthropogenic sound is present (De Ruiter et al., 2013; 
Manzano-Roth et al., 2013; Moretti et al., 2014; Tyack et al., 2011). 
Research involving tagged Cuvier's beaked whales in the SOCAL Range 
Complex reported on by Falcone and Schorr (2012, 2014) indicates year-
round prolonged use of the Navy's training and testing area by these 
beaked whales and has documented movements in excess of hundreds of 
kilometers by some of those animals. Given that some of these animals 
may routinely move hundreds of kilometers as part of their normal 
pattern, leaving an area where sonar or other anthropogenic sound is 
present may have little, if any, cost to such an animal. Photo 
identification studies in the SOCAL Range Complex, a Navy range that is 
utilized for training and testing, have identified approximately 100 
Cuvier's beaked whale individuals with 40 percent having been seen in 
one or more prior years, with re-sightings up to seven years apart 
(Falcone and Schorr, 2014). These results indicate long-term residency 
by individuals in an intensively used Navy training and testing area, 
which may also suggest a lack of long-term consequences as a result of 
exposure to Navy training and testing activities. More than eight years 
of passive acoustic monitoring on the Navy's instrumented range west of 
San Clemente Island documented no significant changes in annual and 
monthly beaked whale echolocation clicks, with the exception of 
repeated fall declines likely driven by natural beaked whale life 
history functions (DiMarzio et al., 2018). Finally, results from 
passive acoustic monitoring estimated that regional Cuvier's beaked 
whale densities were higher than indicated by NMFS' broad scale visual 
surveys for the U.S. West Coast (Hildebrand and McDonald, 2009).
    Below we compile and summarize the information that supports our 
determination that the Navy's activities will not adversely affect 
beaked whales through effects on annual rates of recruitment or 
survival.
Baird's and Cuvier's Beaked Whales and Mesoplodon Species
California/Oregon/Washington Stocks
    Baird's beaked whale, Cuvier's beaked whale, and the Mesoplodon 
species are not listed as endangered or threatened species under the 
ESA, and the CA/OR/WA stocks have been identified as ``stable,'' 
``decreasing,'' and ``increasing,'' respectively, in the SARs. No 
biologically important areas have been identified for beaked whales in 
the NWTT Study Area. No mortality or Level A harassment from sonar or 
explosives is expected or authorized.
    No methods are available to distinguish between the six species of 
Mesoplodon beaked whales from the CA/OR/WA stocks (Blainville's beaked 
whale (M. densirostris), Perrin's beaked whale (M. perrini), Lesser 
beaked whale (M. peruvianus), Stejneger's beaked whale (M. stejnegeri), 
Gingko-toothed beaked whale (M. gingkodens), and Hubbs' beaked whale 
(M. carlhubbsi)) when observed during at-sea surveys

[[Page 72448]]

(Carretta et al., 2019). Bycatch and stranding records from the region 
indicate that Hubb's beaked whale is the most commonly encountered 
(Carretta et al., 2008, Moore and Barlow, 2013). As indicated in the 
SAR, no species-specific abundance estimates are available, the 
abundance estimate includes all CA/OR/WA Mesoplodon species, and the 
six species/stocks are managed as one unit. Due to the lack of species-
specific abundance estimates it is not possible to predict the take of 
individual species for each stock and take estimates are identified as 
Mesoplodon species. Therefore our analysis considers these Mesoplodon 
species together.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance is 36 to 78 percent. This information 
indicates that potentially half or more (but no more than 78 percent) 
of the individuals in these stocks may be impacted, depending on the 
stock, though the more likely scenario is that a smaller portion than 
that would be taken, and a subset of them would be taken on a few days, 
with no indication that these days would be sequential. Regarding the 
severity of those individual takes by Level B harassment by behavioral 
disturbance, we have explained that the duration of any exposure is 
expected to be between minutes and hours (i.e., relatively short) and 
the received sound levels largely below 166 dB, though with beaked 
whales, which are considered somewhat more sensitive, this could mean 
that some individuals will leave preferred habitat for a day (i.e., 
moderate level takes). However, while interrupted feeding bouts are a 
known response and concern for odontocetes, we also know that there are 
often viable alternative habitat options nearby. Regarding the severity 
of TTS takes, they are expected to be low-level, of short duration, and 
mostly not in a frequency band that would be expected to interfere with 
beaked whale communication or other important low-frequency cues, and 
that the associated lost opportunities and capabilities are not at a 
level that will impact reproduction or survival. As mentioned earlier 
in the odontocete overview, we anticipate more severe effects from 
takes when animals are exposed to higher received levels or sequential 
days of impacts.
    Altogether, none of these species are listed as threatened or 
endangered under the ESA, only a portion of the stocks are anticipated 
to be impacted, and any individual beaked whale is likely to be 
disturbed at a moderate or sometimes low level. This low magnitude and 
moderate to lower severity of harassment effects is not expected to 
result in impacts on individual reproduction or survival, let alone 
annual rates of recruitment or survival. No mortality or Level A 
harassment is anticipated or authorized. For these reasons, we have 
determined, in consideration of all of the effects of the Navy's 
activities combined, that the authorized take will have a negligible 
impact on the CA/OR/WA stocks of beaked whales.
Dolphins and Small Whales
    This section builds on the broader odontocete discussion above and 
brings together the discussion of the different types and amounts of 
take that different dolphin and small whale species and stocks are 
likely to incur, any additional applicable mitigation, and the status 
of the species and stocks to support the negligible impact 
determinations for each species or stock. For all dolphin and small 
whale stocks discussed here, no mortality or tissue damage from sonar 
or explosives is anticipated or authorized. No PTS from sonar or 
explosives is predicted, except for the CA/OR/WA stocks of Northern 
right whale dolphin and Pacific white-sided dolphin, for which one 
Level A harassment by PTS from testing activities is predicted for each 
stock.
    In Table 55 below for dolphins and small whales, we indicate for 
each species and stock the total annual numbers of take by mortality, 
Level A harassment and Level B harassment, and a number indicating the 
instances of total take as a percentage of abundance.

   Table 55--Annual Estimated Takes by Level B Harassment, Level A Harassment, and Mortality for Dolphins and Small Whales in the NWTT Study Area and
                                    Number Indicating the Instances of Total Take as a Percentage of Stock Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                 Instances of indicated types of incidental take  (not all takes
                                                   represent separate individuals, especially for disturbance)
                                               ------------------------------------------------------------------                             Instances
                                                    Level B harassment        Level A harassment                                Abundance     of total
           Species                  Stock      -----------------------------------------------------              Total takes  (NMFS SARs)     take as
                                                               TTS (may                               Mortality                     *        percentage
                                                 Behavioral  also include      PTS         Tissue                                           of abundance
                                                disturbance  disturbance)                  damage
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Family Delphinidae (dolphins)
                                                            Family Ziphiidae (beaked whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Common bottlenose dolphin....  CA/OR/WA                   8             0            0            0            0            8        1,924            <1
                                Offshore.
Killer whale.................  Eastern North             34             0            0            0            0           34        2,347             1
                                Pacific Alaska
                                Resident.
                               West Coast               210            22            0            0            0          232          243            95
                                Transient.
                               Eastern North            152             5            0            0            0          157          300            52
                                Pacific
                                Offshore.
                               Eastern North             49             2            0            0            0           51           75            68
                                Pacific
                                Southern
                                Resident.
Northern right whale dolphin.  CA/OR/WA.......       20,671         1,029            1            0            0       21,701       26,556            82
Pacific white-sided dolphin..  North Pacific..          101             0            0            0            0          101       26,880            <1
                               CA/OR/WA.......       19,593         1,372            1            0            0       20,966       26,814            78
Risso's dolphin..............  CA/OR/WA.......        6,080           275            0            0            0        6,355        6,336           100
Short-beaked common dolphin..  CA/OR/WA.......        2,103            46            0            0            0        2,149      969,861            <1
Short-finned pilot whale.....  CA/OR/WA.......           87             1            0            0            0           88          836            11

[[Page 72449]]

 
Striped dolphin..............  CA/OR/WA.......          763            20            0            0            0          783       29,211             3
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Presented in the 2019 SARs or most recent SAR.

    As described above, the large majority of Level B harassment by 
behavioral disturbance to odontocetes, and thereby dolphins and small 
whales, from hull-mounted sonar (MFAS) in the NWTT Study Area would 
result from received levels between 160 and 172 dB SPL. Therefore, the 
majority of takes by Level B harassment for dolphins and small whales 
are expected to be in the form of low to occasionally moderate 
responses of a generally shorter duration. As mentioned earlier in this 
section, we anticipate more severe effects from takes when animals are 
exposed to higher received levels or for longer durations. Occasional 
milder occurrences of Level B harassment by behavioral disturbance, as 
is expected here, are unlikely to cause long-term consequences for 
individual animals or populations that have any effect on reproduction 
or survival.
    Research and observations show that if delphinids are exposed to 
sonar or other active acoustic sources they may react in a number of 
ways depending on their experience with the sound source and what 
activity they are engaged in at the time of the acoustic exposure. 
Delphinids may not react at all until the sound source is approaching 
within a few hundred meters to within a few kilometers depending on the 
environmental conditions and species. Some dolphin species (the more 
surface-dwelling taxa--typically those with ``dolphin'' in the common 
name, such as bottlenose dolphins, spotted dolphins, spinner dolphins, 
rough-toothed dolphins, etc., but not Risso's dolphin), especially 
those residing in more industrialized or busy areas, have demonstrated 
more tolerance for disturbance and loud sounds and many of these 
species are known to approach vessels to bow-ride. These species are 
often considered generally less sensitive to disturbance. Dolphins and 
small whales that reside in deeper waters and generally have fewer 
interactions with human activities are more likely to demonstrate more 
typical avoidance reactions and foraging interruptions as described 
above in the odontocete overview.
    Below we compile and summarize the information that supports our 
determination that the Navy's activities will not adversely affect 
dolphins and small whales through effects on annual rates of 
recruitment or survival.
Killer Whales (Eastern North Pacific Southern Resident Stock)
    The Eastern North Pacific Southern Resident stock (Southern 
Resident killer whale DPS) is listed as endangered under the ESA. ESA-
designated critical habitat for the Southern Resident killer whale DPS 
overlaps with the NWTT Study Area in the Strait of Juan de Fuca and 
Washington inland waters. No other biologically important areas for 
killer whales have been identified in the NWTT Study Area. The Eastern 
North Pacific Southern Resident stock is small (75 individuals) and has 
been decreasing in recent years. No mortality or Level A harassment is 
anticipated or authorized for the Eastern North Pacific Southern 
Resident stock of killer whales.
    The Marine Species Coastal, Olympic Coast National Marine 
Sanctuary, Stonewall and Heceta Bank Humpback Whale, Point St. George 
Humpback Whale, and Puget Sound and Strait of Juan de Fuca Mitigation 
Areas overlap with important Eastern North Pacific Southern Resident 
(Southern Resident DPS) killer whale foraging and migration habitat, as 
described in the proposed rule and this final rule. The mitigation 
measures implemented in each of these areas include, but are not 
limited to, no MF1 MFAS use seasonally or limited MFAS use year round, 
no explosive training or restrictions on explosive training, and no 
explosive testing or restrictions on explosive testing. For complete 
details on mitigation measures for each area, see Table 50 and 
discussion in the Mitigation Measures section of this rule. As stated 
in the Mitigation Areas section of this final rule, new mitigation in 
the Puget Sound and Strait of Juan de Fuca Mitigation Area is designed 
to help avoid any potential impacts from training and testing on 
Southern Resident killer whales in NWTT Inland Waters. With 
implementation of these new mitigation measures, we do not anticipate 
any take of Southern Resident killer whales in NWTT Inland Waters due 
to NWTT training and testing activities.
    Additionally, this final rule includes a new mitigation area, the 
Juan de Fuca Eddy Marine Species Mitigation Area, in which MF1 MFAS 
will be restricted and explosives prohibited. Waters within the Juan de 
Fuca Eddy Marine Species Mitigation Area (including areas off Cape 
Flattery) are important migration habitat for Eastern North Pacific 
Southern Resident killer whales as they transit between Inland Waters 
and the Offshore Area. In addition, Eastern North Pacific Southern 
Resident killer whales will benefit from the procedural mitigation 
measures described earlier in the Mitigation Measures section. All of 
these measures will reduce the severity of impacts to Eastern North 
Pacific Southern Resident (Southern Resident DPS) killer whales by 
reducing interference in feeding and migration that could result in 
lost feeding opportunities or necessitate additional energy expenditure 
to find other good foraging opportunities or migration routes. 
Altogether, the mitigation measures in this final rule result in a 
significant reduction in activities likely to disturb Eastern North 
Pacific Southern Resident killer whales across a large portion of their 
range within the NWTT Study Area, and especially within inland waters.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance for the Eastern North Pacific Southern 
Resident stock is 68 percent. This information indicates that 
potentially half or more of the individuals in this stock may be 
impacted, though the more likely scenario is that a smaller portion 
than

[[Page 72450]]

that will be taken, and a subset of them will be taken multiple days 
with no indication that these days will be sequential.
    Regarding the severity of those individual takes by Level B 
harassment by behavioral disturbance, we have explained that the 
duration of any exposure is expected to be between minutes and hours 
(i.e., relatively short) and the received sound levels largely below 
172 dB (i.e., of a lower, to occasionally moderate, level and less 
likely to evoke a severe response). Regarding the severity of TTS 
takes, they are expected to be low-level, of short duration, and mostly 
not in a frequency band that would be expected to interfere with killer 
whale communication or other important low-frequency cues. Therefore, 
the associated lost opportunities and capabilities are not at a level 
that will impact reproduction or survival.
    Altogether, the Eastern North Pacific Southern Resident killer 
whale stock is listed as endangered under the ESA. Only a portion of 
this killer whale stock is anticipated to be impacted, and any 
individual is likely to be disturbed at a low-moderate level, with 
those individuals likely not disturbed on more than a few non-
sequential days within a year. Even acknowledging the small and 
declining stock size of the Eastern North Pacific Southern Resident 
stock, this low magnitude and severity of harassment effects is 
unlikely to result in impacts on individual reproduction or survival, 
let alone have impacts on annual rates of recruitment or survival of 
the stock. No mortality or Level A harassment is anticipated or 
authorized for the stock. For these reasons, we have determined, in 
consideration of all of the effects of the Navy's activities combined, 
that the authorized take will have a negligible impact on the Eastern 
North Pacific Southern Resident killer whale stock.
Killer Whales (Eastern North Pacific Alaska Resident, West Coast 
Transient, and Eastern North Pacific Offshore Stocks)
    None of these killer whale stocks are listed under the ESA. No 
biologically important areas for killer whales have been identified in 
the NWTT Study Area, other than the Southern Resident ESA-designated 
critical habitat discussed above. The Eastern North Pacific Offshore 
stock is reported as ``stable,'' while the Eastern North Pacific Alaska 
Resident and West Coast Transient stocks have unknown population 
trends. No mortality or Level A harassment is anticipated or authorized 
for any of these stocks.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance ranges from 1 percent (Eastern North 
Pacific Alaska Resident) to 95 percent (West Coast Transient). This 
information indicates that only a very small portion of the Eastern 
North Pacific Alaska Resident stock is likely impacted and repeated 
exposures of individuals are not anticipated (i.e., individuals are not 
expected to be taken on more than one day within a year). This 
information also indicates that potentially half or more of the 
individuals in the other two stocks may be impacted, though the more 
likely scenario is that a smaller portion than that will be taken, and 
a subset of them will be taken multiple days with no indication that 
these days will be sequential.
    Regarding the severity of those individual takes by Level B 
harassment by behavioral disturbance, we have explained that the 
duration of any exposure is expected to be between minutes and hours 
(i.e., relatively short) and the received sound levels largely below 
172 dB (i.e., of a lower, to occasionally moderate, level and less 
likely to evoke a severe response). Regarding the severity of TTS 
takes, they are expected to be low-level, of short duration, and mostly 
not in a frequency band that would be expected to interfere with killer 
whale communication or other important low-frequency cues. Therefore, 
the associated lost opportunities and capabilities are not at a level 
that will impact reproduction or survival.
    Altogether, these killer whale stocks are not listed under the ESA. 
Only a portion of each killer whale stock is anticipated to be 
impacted, and any individual is likely to be disturbed at a low-
moderate level, with the taken individuals likely not disturbed on more 
than a few non-sequential days within a year. This low magnitude and 
severity of harassment effects is unlikely to result in impacts on 
individual reproduction or survival, let alone have impacts on annual 
rates of recruitment or survival of any of the stocks. No mortality or 
Level A harassment is anticipated or authorized for any of the stocks. 
For these reasons, we have determined, in consideration of all of the 
effects of the Navy's activities combined, that the authorized take 
will have a negligible impact on these killer whale stocks.
All Other Dolphin and Small Whale Stocks
    None of these stocks is listed under the ESA and their stock 
statuses are considered ``unknown,'' except for the CA/OR/WA stock of 
short-beaked common dolphin which is described as ``increasing.'' No 
biologically important areas for these stocks have been identified in 
the NWTT Study Area. No mortality or serious injury is anticipated or 
authorized. With the exception of one Level A harassment PTS take each 
for the CA/OR/WA stocks of Northern right whale dolphin and Pacific 
white-sided dolphin, no Level A harassment by PTS or tissue damage is 
expected or authorized for these stocks.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance ranges from less than 1 percent (North 
Pacific stock of Pacific white-sided dolphins, CA/OR/WA Offshore stock 
of common bottlenose dolphins, and CA/OR/WA stock of short-beaked 
common dolphins) to 100 percent (CA/OR/WA stock of Risso's dolphins). 
All stocks except for the CA/OR/WA stocks of Risso's dolphin, Pacific 
white-sided dolphin, and Northern right whale dolphin have estimated 
total instances of take compared to the abundances less than or equal 
to 11 percent. This information indicates that only a small portion of 
these stocks is likely impacted and repeated exposures of individuals 
are not anticipated. The CA/OR/WA stocks of Risso's dolphins, Pacific 
white-sided dolphin, and Northern right whale dolphin have estimated 
total instances of take compared to the abundances that range from 78 
to 100 percent. This information indicates that up to half or more of 
the individuals of these stocks could be impacted, though the more 
likely scenario is that a smaller portion than that will be taken, and 
a subset of them will be taken on a few days, with no indication that 
these days will be sequential.
    Regarding the severity of those individual takes by Level B 
harassment by behavioral disturbance, we have explained that the 
duration of any exposure is expected to be between minutes and hours 
(i.e., relatively short) and the received sound levels largely below 
172 dB (i.e., of a lower, to occasionally moderate, level and less 
likely to evoke a severe response). However, while interrupted feeding 
bouts are a known response and concern for odontocetes, we also know 
that there are often viable alternative habitat options nearby. 
Regarding the severity

[[Page 72451]]

of TTS takes, they are expected to be low-level, of short duration, and 
mostly not in a frequency band that would be expected to interfere with 
dolphin and small whale communication or other important low-frequency 
cues, and that the associated lost opportunities and capabilities are 
not at a level that will impact reproduction or survival. For these 
same reasons (low level and frequency band), while a small permanent 
loss of hearing sensitivity (PTS) may include some degree of energetic 
costs for compensating or may mean some small loss of opportunities or 
detection capabilities, at the expected scale the estimated one Level A 
harassment take by PTS for the CA/OR/WA stocks of Northern right whale 
dolphin and Pacific white-sided dolphin is unlikely to impact 
behaviors, opportunities, or detection capabilities to a degree that 
will interfere with reproductive success or survival of that 
individual. Thus the one Level A harassment take by PTS for these 
stocks is unlikely to affect rates of recruitment and survival for the 
stock.
    Altogether, though the status of these stocks is largely unknown, 
none of these stocks is listed under the ESA and any individual is 
likely to be disturbed at a low to occasionally moderate level, with 
the taken individuals likely exposed on one to a few days. This low 
magnitude and severity of harassment effects is not expected to result 
in impacts on individual reproduction or survival. One individual each 
from the CA/OR/WA stocks of Northern right whale dolphin and Pacific 
white-sided dolphin could be taken by PTS annually of likely low 
severity. A small permanent loss of hearing sensitivity (PTS) may 
include some degree of energetic costs for compensating or may mean 
some small loss of opportunities or detection capabilities, but at the 
expected scale the estimated Level A harassment takes by PTS for the 
CA/OR/WA stocks of Northern right whale dolphin and Pacific white-sided 
dolphin is unlikely to impact behaviors, opportunities, or detection 
capabilities to a degree that will interfere with reproductive success 
or survival of those individuals, let alone annual rates of recruitment 
or survival, either alone, or in combination with the authorized Level 
B harassment. No mortality is anticipated or authorized. For these 
reasons, we have determined, in consideration of all of the effects of 
the Navy's activities combined, that the authorized take will have a 
negligible impact on these stocks of small whales and dolphins.
Porpoises
    This section builds on the broader odontocete discussion above and 
brings together the discussion of the different types and amounts of 
take that different porpoise species or stocks will likely incur, any 
additional applicable mitigation, and the status of the species and 
stocks to support the negligible impact determinations for each species 
or stock. For porpoises, there is no anticipated M/SI or tissue damage 
from sonar or explosives for any species.
    In Table 56 below for porpoises, we indicate the total annual 
numbers of take by mortality, Level A harassment and Level B 
harassment, and a number indicating the instances of total take as a 
percentage of abundance.

Table 56--Annual Estimated Takes by Level B Harassment, Level A Harassment, and Mortality for Porpoises in the NWTT Study Area and Number Indicating the
                                               Instances of Total Take as a Percentage of Stock Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                 Instances of indicated types of incidental take  (not all takes
                                                   represent separate individuals, especially for disturbance)
                                               ------------------------------------------------------------------                             Instances
                                                    Level B harassment        Level A harassment                                Abundance     of total
           Species                  Stock      -----------------------------------------------------              Total takes  (NMFS SARs)     take as
                                                               TTS (may                               Mortality                     *        percentage
                                                 Behavioral  also include      PTS         Tissue                                           of abundance
                                                disturbance  disturbance)                  damage
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Family Phocoenidae (porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dall's porpoise..............  Alaska.........          179           459            0            0            0          638       83,400            <1
                               CA/OR/WA.......       13,407        20,290           98            0            0       33,795       25,750           131
Harbor porpoise..............  Southeast                 92            38            0            0            0          130        1,354            10
                                Alaska.
                               Nothern OR/WA         31,602        20,810          103            0            0       52,515       21,487           244
                                Coast.
                               Northern CA/           1,691           348           86            0            0        2,125       24,195             9
                                Southern OR.
                               Washington            15,146        14,397          180            0            0       29,723       11,233           265
                                Inland Waters.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Presented in the 2019 SARs or most recent SAR, including updates since publication of the proposed rule.

    The majority of takes by harassment of harbor porpoises in the NWTT 
Study Area are caused by sources from the MFAS bin (which includes 
hull-mounted sonar) because they are high level sources at a frequency 
(1-10 kHz) which overlaps a more sensitive portion (though not the most 
sensitive) of the HF hearing range, and of the sources expected to 
result in take, they are used in a large portion of exercises (see 
Tables 3 and 4). Most of the takes (90 percent) from the MF1 bin in the 
NWTT Study Area would result from received levels between 148 and 166 
dB SPL. For the remaining active sonar bin types, the percentages are 
as follows: LF4 = 99 percent between 124 and 142 dB SPL, MF4 = 97 
percent between 124 and 148 dB SPL, MF5 = 97 percent between 118 and 
142 dB SPL, and HF4 = 97 percent between 118 and 160 dB SPL. Given the 
levels they are exposed to and harbor porpoise sensitivity, some 
responses would be of a lower severity, but many would likely be 
considered moderate, but still of generally short duration.
    Harbor porpoises have been shown to be particularly sensitive to 
human activity (Tyack et al., 2011; Pirotta et al., 2012). The 
information currently available regarding harbor porpoises suggests a 
very low threshold level of response for both captive (Kastelein et 
al., 2000; Kastelein et al., 2005) and wild (Johnston, 2002) animals. 
Southall et al. (2007) concluded that harbor porpoises are likely 
sensitive to a wide range of anthropogenic sounds at low received 
levels (approximately 90 to 120 dB). Research and observations of 
harbor porpoises for other locations show that this species is wary of 
human activity and will display profound avoidance behavior for 
anthropogenic

[[Page 72452]]

sound sources in many situations at levels down to 120 dB re: 1 
[micro]Pa (Southall, 2007). Harbor porpoises routinely avoid and swim 
away from large motorized vessels (Barlow et al., 1988; Evans et al., 
1994; Palka and Hammond, 2001; Polacheck and Thorpe, 1990). Harbor 
porpoises may startle and temporarily leave the immediate area of the 
training or testing until after the event ends. Accordingly, harbor 
porpoises have been assigned a lower behavioral harassment threshold, 
i.e., a more distant distance cutoff (40 km for high source level, 20 
km for moderate source level) and, as a result, the number of harbor 
porpoise taken by Level B harassment by behavioral disturbance through 
exposure to LFAS/MFAS/HFAS in the NWTT Study Area is generally higher 
than the other species. As mentioned earlier in the odontocete 
overview, we anticipate more severe effects from takes when animals are 
exposed to higher received levels or sequential days of impacts; 
occasional low to moderate behavioral reactions are unlikely to affect 
reproduction or survival. Some takes by Level B harassment by 
behavioral disturbance could be in the form of a longer (several hours 
or a day) and more moderate response, but unless they are repeated over 
more than several sequential days, impacts to reproduction or survival 
are not anticipated.
    While harbor porpoises have been observed to be especially 
sensitive to human activity, the same types of responses have not been 
observed in Dall's porpoises. Dall's porpoises are typically notably 
longer than, and weigh more than twice as much as, harbor porpoises, 
making them generally less likely to be preyed upon and likely 
differentiating their behavioral repertoire somewhat from harbor 
porpoises. Further, they are typically seen in large groups and feeding 
aggregations, or exhibiting bow-riding behaviors, which is very 
different from the group dynamics observed in the more typically 
solitary, cryptic harbor porpoises, which are not often seen bow-
riding. For these reasons, Dall's porpoises are not treated as an 
especially sensitive species (versus harbor porpoises which have a 
lower behavioral harassment threshold and more distant cutoff) but, 
rather, are analyzed similarly to other odontocetes (with takes from 
the sonar bin in the NWTT Study Area resulting from the same received 
levels reported in the Odontocete section above). Therefore, the 
majority of Level B harassment by behavioral disturbance is expected to 
be in the form of milder responses compared to higher level exposures. 
As mentioned earlier in this section, we anticipate more severe effects 
from takes when animals are exposed to higher received levels.
    We note that both Dall's and harbor porpoises, as HF-sensitive 
species, have a lower PTS threshold than other groups and therefore are 
generally likely to experience larger amounts of TTS and PTS, and NMFS 
accordingly has evaluated and authorized higher numbers. Also, however, 
regarding PTS from sonar exposure, porpoises are still likely to avoid 
sound levels that would cause higher levels of TTS (greater than 20 dB) 
or PTS. Therefore, even though the number of TTS takes are higher than 
for other odontocetes, any PTS is expected to be at a lower level and 
for all of the reasons described above, TTS and PTS takes are not 
expected to impact reproduction or survival of any individual.
All Porpoise Stocks
    These Dall's and harbor porpoise stocks are not listed under the 
ESA and the status of these stocks is considered ``unknown.'' No 
biologically important areas have been identified for Dall's and harbor 
porpoises in the NWTT Study Area. However, a known important feeding 
area for harbor porpoises overlaps with the Stonewall and Heceta Bank 
Humpback Whale Mitigation Area. No MF1 MFAS or explosives will be used 
in this mitigation area from May 1--November 30, which will reduce the 
severity of impacts to harbor porpoises by reducing interference in 
feeding that could result in lost feeding opportunities or necessitate 
additional energy expenditure to find other good opportunities. No 
mortality or Level A harassment from tissue damage is expected or 
authorized for any of these stocks.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), the number of estimated total instances of 
take compared to the abundance ranges from less than 1 percent for the 
Alaska stock of Dall's porpoises to 265 percent for the Washington 
Inland Waters stock of harbor porpoises. The Alaska stock of Dall's 
porpoises, and the Southeast Alaska and Northern California/Southern 
Oregon stocks of harbor porpoises have estimated total instances of 
take compared to the abundances less than or equal to 10 percent. This 
information indicates that only a small portion of these stocks is 
likely impacted and repeated exposures of individuals are not 
anticipated (i.e., individuals are not expected to be disturbed on more 
than one day a year). The CA/OR/WA stock of Dall's porpoises and the 
Northern Washington/Oregon Coast and Washington Inland Waters stocks of 
harbor porpoises have estimated total instances of take compared to the 
abundances that range from 131 to 265 percent. This information 
indicates that likely half or more, and potentially the majority of the 
individuals of these stocks could be impacted, though the more likely 
scenario is that a smaller portion will be taken, and a subset of those 
will be taken on up to 5 or 6 days, with no indication that these days 
will be sequential. In the proposed rule, we stated that due to the 
potential number of repeated takes of some individuals it was possible 
that some small number of females could forego reproduction for a year. 
Since the proposed rule, we have reevaluated the estimated number of 
harassment takes, where the potential number of repeated takes annually 
is limited to 5 or 6 days with no indication of take on sequential 
days, and determined that foregone reproduction is unlikely to occur.
    Regarding the severity of those individual takes by Level B 
harassment by behavioral disturbance for harbor porpoises, we have 
explained that the duration of any exposure is expected to be between 
minutes and hours (i.e., relatively short) and the received sound 
levels largely below 166 dB, which for harbor porpoise (which have a 
lower threshold for Level B harassment by disturbance) would be 
considered a moderate level. Regarding the severity of those individual 
takes by Level B harassment by behavioral disturbance for Dall's 
porpoises, we have explained that the duration of any exposure is 
expected to be between minutes and hours (i.e., relatively short) and 
the received sound levels largely below 172 dB (i.e., of a lower, to 
occasionally moderate, level and less likely to evoke a severe 
response). Regarding the severity of TTS takes, they are expected to be 
low-moderate level, of short duration, and mostly not in a frequency 
band that would be expected to interfere with communication or other 
important low-frequency cues. The associated lost opportunities and 
capabilities are not at a level that will impact reproduction or 
survival.
    No Level A harassment by PTS is anticipated or authorized for the 
Southeast Alaska stock of harbor porpoise or the Alaska stock of Dall's 
porpoise. For the remaining porpoise stocks, for the same reasons 
explained above for TTS (low level and the likely frequency band), 
while a small permanent loss of hearing sensitivity

[[Page 72453]]

may include some degree of energetic costs for compensating or may mean 
some small loss of opportunities or detection capabilities, the 
estimated annual Level A harassment takes by PTS for these three stocks 
of harbor porpoises and one stock of Dall's porpoises (86 to 180) will 
be unlikely to impact behaviors, opportunities, or detection 
capabilities to a degree that will interfere with reproductive success 
or survival. In the proposed rule, we stated that due to the estimated 
number of PTS takes it was possible that some small number of females 
could incur a higher degree of PTS that could interfere with their 
successful reproduction and growth. Since the proposed rule, we have 
reevaluated the likelihood of PTS impacts of a higher degree and 
determined that they are unlikely to occur, given the anticipated 
avoidance of loud sounds at the distances and durations necessary to 
incur more severe PTS.
    Altogether, the status of the harbor porpoise stocks is unknown, 
however harbor porpoises are not listed as endangered or threatened 
under the ESA. Because harbor porpoises are particularly sensitive, it 
is likely that a fair number of the Level B harassment behavioral 
responses of individuals will be of a moderate nature. Additionally, as 
noted, some portion of the stocks may be taken repeatedly on up to 5 or 
6 non-sequential days within a year, however this is not anticipated to 
affect the stocks' annual rates of recruitment or survival. Some 
individuals (86 to 180) from the Northern Oregon/Washington Coast, 
Northern California/Southern Oregon, and Washington Inland Waters 
stocks of harbor porpoises could be taken by PTS annually of likely low 
severity. A small permanent loss of hearing sensitivity (PTS) may 
include some degree of energetic costs for compensating or may mean 
some small loss of opportunities or detection capabilities, but at the 
expected scale the estimated Level A harassment takes by PTS for these 
stocks is unlikely, alone or in combination with the Level B harassment 
take by behavioral disturbance, to impact behaviors, opportunities, or 
detection capabilities to a degree that will interfere with 
reproductive success or survival of any individuals, let alone annual 
rates of recruitment or survival. No mortality is anticipated or 
authorized. For these reasons, we have determined, in consideration of 
all of the effects of the Navy's activities combined, that the 
authorized take will have a negligible impact on all four stocks of 
harbor porpoises.
    Altogether, the status of the Dall's porpoise stocks is unknown, 
however Dall's porpoises are not listed as endangered or threatened 
under the ESA. Any individual Dall's porpoise is likely to be disturbed 
at a low-moderate level, with the taken individuals likely exposed on 
one to a few days. This low magnitude and low-moderate severity of 
Level B harassment effects is not expected to result in impacts on 
individual reproduction or survival, much less annual rates of 
recruitment or survival. Some individuals (98) from the CA/OR/WA stock 
of Dall's porpoises could be taken by PTS annually of likely low 
severity. A small permanent loss of hearing sensitivity (PTS) may 
include some degree of energetic costs for compensating or may mean 
some small loss of opportunities or detection capabilities, but at the 
expected scale the estimated Level A harassment takes by PTS for this 
stock are unlikely, alone or in combination with the Level B harassment 
take by behavioral disturbance, to impact behaviors, opportunities, or 
detection capabilities to a degree that will interfere with 
reproductive success or survival of any individuals, let alone annual 
rates of recruitment or survival. No mortality is anticipated or 
authorized. For these reasons, we have determined, in consideration of 
all of the effects of the Navy's activities combined, that the 
authorized take will have a negligible impact on these two stocks of 
Dall's porpoises.
Pinnipeds
    This section builds on the broader discussion above and brings 
together the discussion of the different types and amounts of take that 
different species and stocks of pinnipeds will likely incur, the 
applicable mitigation, and the status of the species and stocks to 
support the negligible impact determinations for each species or stock. 
We have described (above in the General Negligible Impact Analysis 
section) the unlikelihood of any masking having effects that will 
impact the reproduction or survival of any of the individual marine 
mammals affected by the Navy's activities. We have also described in 
the Potential Effects of Specified Activities on Marine Mammals and 
their Habitat section of the proposed rule that the specified 
activities would not have adverse or long-term impacts on marine mammal 
habitat, and therefore the unlikelihood of any habitat impacts 
affecting the reproduction or survival of any individual marine mammals 
affected by the Navy's activities. For pinnipeds, there is no mortality 
or serious injury and no Level A harassment from tissue damage from 
sonar or explosives anticipated or authorized for any species. Here, we 
include information that applies to all of the pinniped species and 
stocks.
    In Table 57 below for pinnipeds, we indicate the total annual 
numbers of take by mortality, Level A harassment and Level B 
harassment, and a number indicating the instances of total take as a 
percentage of abundance.
    This final rule reflects an updated abundance estimate for the 
Washington Northern Inland Waters stock, Hood Canal stock, and Southern 
Puget Sound stock of harbor seal. The Navy derived an in-water harbor 
seal abundance of 3,116 for Washington Northern Inland Waters by 
summing abundances for Admiralty Inlet (516), East Whidbey (1,926), and 
South Whidbey (674) from Smultea et al., (2017). Smultea et al. (2017) 
did not provide an abundance or correction factor for animals hauled 
out of the water in these locations. Therefore, the Navy utilized a 
correction factor of 1.53 (Huber et al., 2001), but it is important to 
note that this correction factor applies for counts of hauled-out 
animals (e.g., animals hauled out multiplied by the correction factor 
for animals in-water = total abundance). Therefore, the Navy applied a 
``reverse'' correction factor (3,116/0.53 = 5,879) to account for 
hauled-out animals. In addition, Smultea et al. (2017) did not survey 
the Strait of Juan de Fuca and San Juan Islands for harbor seals. 
However, NMFS includes the Strait and San Juan Islands as part of the 
WA Northern Inland Waters stock in the SAR. Thus, the abundance (13,775 
seals) calculated to estimate a density, based on haul-out counts by S. 
Jeffries in summer 2013 and 2014, is added to the Smultea et al. total 
abundance. Therefore, the total stock abundance estimate is equal to 
the sum of the in-water abundance plus the estimated abundance of 
hauled-out animals, plus the abundance for the Strait of Juan de Fuca 
and San Juan Islands, (3,116 + 5,879 + 13,775 = 22,770 total harbor 
seals in Washington Northern Inland Waters). NMFS concurs with this 
assessment and uses 22,770 as the abundance estimate for the Washington 
Northern Inland Waters stock of harbor seal in this final rule.
    Regarding the Hood Canal stock, Jefferson et al. (2017) estimates 
an in-water abundance of 2,009 harbor seals in the Hood Canal study 
region. The in-water abundance provided in Jefferson et al. (2017) did 
not provide an abundance or correction factor for animals hauled out of 
the water. Therefore, the Navy utilized a correction

[[Page 72454]]

factor of 1.53 (Huber et al., 2001), but, as explained above, this 
correction factor applies for counts of hauled-out animals (e.g., 
animals hauled out multiplied by the correction factor for animals in-
water = total abundance). Therefore, the Navy applied the same 
``reverse'' correction factor (2,009/0.53 = 3,791) to account for 
animals hauled out. Therefore, the total stock abundance estimate is 
equal to the sum of the in-water abundance plus the estimated abundance 
of hauled-out animals (2,009 + 3,791 = 5,800 total Hood Canal harbor 
seals). NMFS concurs with this assessment and uses 5,800 as the 
abundance estimate for the Hood Canal stock of harbor seal in this 
final rule.
    The Navy derived an in-water harbor seal abundance estimate of 
4,042 for the Southern Puget Sound stock by summing in-water abundances 
for Bainbridge (301), Seattle (252), Southern Puget Sound (2,905), and 
Vashon (584) included in Smultea et al. (2017). Smultea et al. (2017) 
did not provide an abundance or correction factor for animals hauled 
out of the water in these locations. Therefore, the Navy utilized the 
same correction factor of 1.53 (Huber et al., 2001). But as with the 
two stocks discussed above, the correction factor applies for counts of 
hauled-out animals (e.g., animals hauled out x the correction factor 
for animals in-water = total abundance). Therefore, the Navy applied 
the same ``reverse'' correction factor (4,042/0.53 = 7,626), to account 
for hauled-out animals. Therefore, the total stock abundance estimate 
is equal to the sum of the in-water abundance plus the estimated 
abundance of hauled-out animals (4,042 + 7,626 = 11,668 total harbor 
seals in WA Southern Puget Sound). NMFS concurs with this assessment 
and uses 11,668 as the abundance estimate for the Southern Puget Sound 
stock of harbor seal in this final rule.

Table 57--Annual Estimated Takes by Level B Harassment, Level A Harassment, and Mortality for Pinnipeds in the NWTT Study Area and Number Indicating the
                                               Instances of Total Take as a Percentage of Stock Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                 Instances of indicated types of incidental take  (not all takes
                                                   represent separate individuals, especially for disturbance)
                                               ------------------------------------------------------------------                             Instances
                                                    Level B harassment        Level A harassment                                Abundance     of total
           Species                  Stock      -----------------------------------------------------              Total takes  (NMFS SARs)     take as
                                                               TTS (may                               Mortality                     *        percentage
                                                 Behavioral  also include      PTS         Tissue                                           of abundance
                                                disturbance  disturbance)                  damage
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Suborder Pinnipedia
                                                       Family Phocidae (eared seals and sea lions)
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion..........  U.S............       23,756           342            1            0            0       24,099      257,606             9
Guadelupe fur seal...........  Mexico to              1,482            13            0            0            0        1,495       34,187             4
                                California.
Northern fur seal............  Eastern Pacific       11,462           130            0            0            0       11,592      620,660             2
                               California.....          231             1            0            0            0          232       14,050             2
Steller sea lion.............  Eastern U.S....        2,231             7            0            0            0        2,238       43,201             5
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Family Phocidae (true seals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor seal..................  Southeast              2,077           275            0            0            0        2,352       27,659             9
                                Alaska
                                (Clarence
                                Strait).
                               OR/WA Coast....          540           640            2            0            0        1,182       24,732             5
                               Washington               870           377            5            0            0        1,252   \1\ 22,770             5
                                Northern
                                Inland Waters.
                               Hood Canal.....       38,430        23,040            1            0            0       61,471    \1\ 5,800         1,060
                               Southern Puget         3,274         3,564            4            0            0        6,842   \1\ 11,668            59
                                Sound.
Northern Elephant seal.......  California.....        4,134           710            4            0            0        4,848      179,000             3
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Presented in the 2019 SARs or most recent SAR except where noted otherwise.
\1\ Recent survey data in the inland waters has not been incorporated into the SARs for these specific stocks, therefore we have used recent Navy
  abundance estimates for these stocks for the negligible impact analysis. These abundance estimates are described in detail in this section of the
  rule.

    As described above, the majority of takes by harassment of 
pinnipeds in the NWTT Study Area are caused by sources from the MFAS 
bin (which includes hull-mounted sonar) because they are high level 
sources at a frequency (1-10 kHz) which overlaps the most sensitive 
portion of the pinniped hearing range, and of the sources expected to 
result in take, they are used in a large portion of exercises (see 
Tables 3 and 4). Most of the takes (97 percent) from the MF1 bin in the 
NWTT Study Area would result from received levels between 166 and 178 
dB SPL. For the remaining active sonar bin types, the percentages are 
as follows: LF4 = 97 percent between 130 and 160 dB SPL, MF4 = 99 
percent between 142 and 172 dB SPL, MF5 = 97 percent between 130 and 
160 dB SPL, and HF4 = 99 percent between 100 and 172 dB SPL. Given the 
levels they are exposed to and pinniped sensitivity, most responses 
will be of a lower severity, with only occasional responses likely to 
be considered moderate, but still of generally short duration.
    As mentioned earlier in this section, we anticipate more severe 
effects from takes when animals are exposed to higher received levels. 
Occasional milder takes by Level B harassment by behavioral disturbance 
are unlikely to cause long-term consequences for individual animals or 
populations, especially when they are not expected to be repeated over 
multiple sequential days. For all pinnipeds, harassment takes from 
explosives (behavioral disturbance, TTS, or PTS if present) comprise a 
very small fraction of those caused by exposure to active sonar.
    Because the majority of harassment take of pinnipeds results from 
narrowband sources in the range of 1-10 kHz, the vast majority of 
threshold shift caused by Navy sonar sources will typically occur in 
the range of 2-20 kHz. This frequency range falls within the range of 
pinniped hearing, however, pinniped vocalizations typically span a 
somewhat lower range than this (<0.2 to 10 kHz) and threshold shift 
from active sonar will often be in a narrower band (reflecting the 
narrower band source that caused it), which means that TTS

[[Page 72455]]

incurred by pinnipeds will typically only interfere with communication 
within a portion of a pinniped's range (if it occurred during a time 
when communication with conspecifics was occurring). As discussed 
earlier, it would only be expected to be of a short duration and 
relatively small degree. Many of the other critical sounds that serve 
as cues for navigation and prey (e.g., waves, fish, invertebrates) 
occur below a few kHz, which means that detection of these signals will 
not be inhibited by most threshold shifts either. The very low number 
of takes by threshold shifts that might be incurred by individuals 
exposed to explosives will likely be lower frequency (5 kHz or less) 
and spanning a wider frequency range, which could slightly lower an 
individual's sensitivity to navigational or prey cues, or a small 
portion of communication calls, for several minutes to hours (if 
temporary) or permanently.
    Regarding behavioral disturbance, research and observations show 
that pinnipeds in the water may be tolerant of anthropogenic noise and 
activity (a review of behavioral reactions by pinnipeds to impulsive 
and non-impulsive noise can be found in Richardson et al. (1995) and 
Southall et al. (2007)). Available data, though limited, suggest that 
exposures between approximately 90 and 140 dB SPL do not appear to 
induce strong behavioral responses in pinnipeds exposed to non-pulse 
sounds in water (Costa et al., 2003; Jacobs and Terhune, 2002; 
Kastelein et al., 2006c). Based on the limited data on pinnipeds in the 
water exposed to multiple pulses (small explosives, impact pile 
driving, and seismic sources), exposures in the approximately 150 to 
180 dB SPL range generally have limited potential to induce avoidance 
behavior in pinnipeds (Blackwell et al., 2004; Harris et al., 2001; 
Miller et al., 2004). If pinnipeds are exposed to sonar or other active 
acoustic sources they may react in a number of ways depending on their 
experience with the sound source and what activity they are engaged in 
at the time of the acoustic exposure. Pinnipeds may not react at all 
until the sound source is approaching within a few hundred meters and 
then may alert, ignore the stimulus, change their behaviors, or avoid 
the immediate area by swimming away or diving. Effects on pinnipeds in 
the NWTT Study Area that are taken by Level B harassment, on the basis 
of reports in the literature as well as Navy monitoring from past 
activities, will likely be limited to reactions such as increased 
swimming speeds, increased surfacing time, or decreased foraging (if 
such activity were occurring). Most likely, individuals will simply 
move away from the sound source and be temporarily displaced from those 
areas, or not respond at all, both of which will have no effect on 
reproduction or survival of the individuals. In areas of repeated and 
frequent acoustic disturbance, some animals may habituate or learn to 
tolerate the new baseline or fluctuations in noise level. Habituation 
can occur when an animal's response to a stimulus wanes with repeated 
exposure, usually in the absence of unpleasant associated events 
(Wartzok et al., 2003). While some animals may not return to an area, 
or may begin using an area differently due to training and testing 
activities, most animals are expected to return to their usual 
locations and behavior. Given their documented tolerance of 
anthropogenic sound (Richardson et al., 1995 and Southall et al., 
2007), repeated exposures of individuals of any of these species to 
levels of sound that may cause Level B harassment are unlikely to 
result in permanent hearing impairment or to significantly disrupt 
(through direct disturbance or opportunities lost during TTS) foraging, 
resting, or reproductive behaviors in a manner that would reduce 
reproductive success or health. Thus, even repeated Level B harassment 
of some subset of individuals of an overall stock is unlikely to result 
in any significant realized decrease in fitness to those individuals 
that would result in any effect on rates of recruitment or survival for 
the stock as a whole.
    Of these stocks, only Guadalupe fur seals are listed under the ESA 
(as threatened), with the SAR indicating the stock is ``increasing.'' 
No critical habitat is designated under the ESA for the Guadalupe fur 
seal. The other stocks are not ESA-listed. There is an active UME for 
Guadalupe fur seals. Since 2015 there have been 400 strandings of 
Guadalupe fur seals (including live and dead seals). The California sea 
lion UME was recently closed as elevated strandings occurred from 2013-
2016. All of the other pinniped stocks are considered ``increasing,'' 
``stable,'' or ``unknown'' except for Northern fur seals (Eastern 
Pacific stock), which is considered to be ``declining.'' There are no 
known biologically important areas for any of the pinniped stocks. No 
mortality or Level A harassment from tissue damage is anticipated or 
authorized. All the pinniped species and stocks discussed in this 
section will benefit from the procedural mitigation measures described 
earlier in the Mitigation Measures section.
    Regarding the magnitude of takes by Level B harassment (TTS and 
behavioral disturbance), with the exception of the Hood Canal and 
Southern Puget Sound stocks of harbor seals, the number of estimated 
total instances of take compared to the abundance is 2-9 percent. Given 
this information and the ranges of these stocks (i.e., large ranges, 
but with individuals often staying in the vicinity of haulouts), only a 
small portion of individuals in the stock are likely impacted and 
repeated exposures of individuals are not anticipated (i.e., 
individuals are not expected to be taken on more than one day within a 
year). For the Southern Puget Sound stock of harbor seals, the number 
of estimated total instances of take compared to the abundance is 59 
percent. This information indicates that fewer than half of the 
individuals in this stock are likely impacted, with those individuals 
likely not disturbed on more than a few non-sequential days a year.
    For the Hood Canal stock of harbor seals, the number of estimated 
total instances of take compared to the abundance is 1,060 percent. 
This information indicates that all individuals of this stock could be 
impacted, though the more likely scenario is that some individuals may 
not be taken at all, some may be taken on 10 or fewer days per year, 
and some could be taken on more than 10 and up to 21 days a year. For 
those individuals taken on a higher number of days, some of those days 
may be sequential. Though the majority of impacts are expected to be of 
a lower to sometimes moderate severity, the repeated takes over some 
number of sequential days for some individuals in the Hood Canal stock 
of harbor seals makes it more likely that some small number of 
individuals could be interrupted during foraging in a manner and amount 
such that impacts to the energy budgets of females (from either losing 
feeding opportunities or expending considerable energy to find 
alternative feeding options) could cause them to forego reproduction 
for a year (energetic impacts to males are generally meaningless to 
population rates unless they cause death, and it takes extreme energy 
deficits beyond what would ever be likely to result from these 
activities to cause the death of an adult marine mammal). We note, 
though, that there is documented evidence of an increasing population 
for Hood Canal harbor seals, despite high levels of acoustic activity 
in their habitat, including pile driving, pierside sonar maintenance/
testing, and testing activities in Dabob Bay. This documented expansion 
includes, for

[[Page 72456]]

example, pupping on the Naval Base Kitsap Bangor waterfront in recent 
years. As noted previously, however, foregone reproduction (especially 
for only one year within seven, which is the maximum predicted because 
the small number anticipated in any one year makes the probability that 
any individual will be impacted in this way twice in seven years very 
low) has far less of an impact on population rates than mortality and 
the relatively small number of instances of foregone reproduction that 
could occur are not expected to adversely affect the stock through 
effects on annual rates of recruitment or survival. Regarding the 
severity of those individual takes by Level B harassment by behavioral 
disturbance for all pinniped stocks, we have explained that the 
duration of any exposure is expected to be between minutes and hours 
(i.e., relatively short) and the received sound levels largely below 
178 dB, which is considered a relatively low to occasionally moderate 
level for pinnipeds. However, as noted, for the Hood Canal stock of 
harbor seals, some of these takes could occur on some number of 
sequential days.
    Regarding the severity of TTS takes, they are expected to be low-
level, of short duration, and mostly not in a frequency band that would 
be expected to interfere with pinniped communication or other important 
low-frequency cues. Therefore, the associated lost opportunities and 
capabilities are not at a level that will impact reproduction or 
survival. For these same reasons (low level and frequency band), while 
a small permanent loss of hearing sensitivity may include some degree 
of energetic costs for compensating or may mean some small loss of 
opportunities or detection capabilities, the 1-5 estimated takes by 
Level A harassment by PTS for California sea lions, Northern elephant 
seals, and the Washington Northern Inland Waters, Hood Canal, OR/WA 
Coast, and Southern Puget Sound stocks of harbor seals is unlikely to 
impact behaviors, opportunities, or detection capabilities to a degree 
that will interfere with reproductive success or survival of any 
individuals.
    Altogether, all pinniped stocks are considered ``increasing,'' 
``stable,'' or ``unknown'' except for Northern fur seals (Eastern 
Pacific stock), which is considered ``declining'' but is not listed 
under the ESA. Only the Guadalupe fur seal is listed under the ESA, 
with a population that is considered increasing. No mortality for 
pinnipeds is anticipated or authorized. No more than five individuals 
from any pinniped stock are estimated to be taken by PTS, of likely low 
severity, annually. Additionally, no PTS is expected for Guadalupe fur 
seal, Northern fur seal, Steller sea lion, and the Southeast Alaska 
(Clarence Strait) stock of harbor seal. A small permanent loss of 
hearing sensitivity (PTS) may include some degree of energetic costs 
for compensating or may mean some small loss of opportunities or 
detection capabilities, but at the expected scale the estimated Level A 
harassment takes by PTS for these stocks are unlikely, alone or in 
combination with the Level B harassment take, to impact behaviors, 
opportunities, or detection capabilities to a degree that will 
interfere with reproductive success or survival of any individuals, let 
alone annual rates of recruitment or survival. For nearly all pinniped 
stocks (with the exception of the Hood Canal stock of harbor seals) 
only a portion of the stocks are anticipated to be taken by Level B 
harassment and any individual is likely to be disturbed at a low-
moderate level on no more than a few non-sequential days per year. Even 
considering the effects of the UME on the Guadalupe fur seal, this low 
magnitude and severity of harassment effects will not result in impacts 
on individual reproduction or survival, much less annual rates of 
recruitment or survival. For the Hood Canal stock of harbor seals, a 
fair portion of individuals will be taken by Level B harassment (at a 
moderate or sometimes low level) over a comparatively higher number of 
days within a year, and some smaller portion of those individuals may 
be taken on sequential days. However, we do not anticipate the 
relatively small number of individual harbor seals that might be taken 
over repeated days within the year in a manner that results in one year 
of foregone reproduction to adversely affect the stock through effects 
on rates of recruitment or survival, given the status of the stock. For 
these reasons, in consideration of all of the effects of the Navy's 
activities combined, we have determined that the authorized take will 
have a negligible impact on all stocks of pinnipeds.

Determination

    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the monitoring and mitigation 
measures, NMFS finds that the total marine mammal take from the 
specified activities will have a negligible impact on all affected 
marine mammal species or stocks.

Subsistence Harvest of Marine Mammals

    In order to issue an incidental take authorization, NMFS must find 
that the total estimated take will not have an ``unmitigable adverse 
impact'' on the availability of the affected marine mammal species or 
stocks for taking for subsistence uses by Alaskan Natives. NMFS has 
defined ``unmitigable adverse impact'' in 50 CFR 216.103 as an impact 
resulting from the specified activity: (1) That is likely to reduce the 
availability of the species to a level insufficient for a harvest to 
meet subsistence needs by: (i) Causing the marine mammals to abandon or 
avoid hunting areas; (ii) Directly displacing subsistence users; or 
(iii) Placing physical barriers between the marine mammals and the 
subsistence hunters; and (2) That cannot be sufficiently mitigated by 
other measures to increase the availability of marine mammals to allow 
subsistence needs to be met.
    When applicable, NMFS must prescribe means of effecting the least 
practicable adverse impact on the availability of the species or stocks 
for subsistence uses. As discussed in the Mitigation Measures section, 
evaluation of potential mitigation measures includes consideration of 
two primary factors: (1) The manner in which, and the degree to which, 
implementation of the potential measure(s) is expected to reduce 
adverse impacts on the availability of species or stocks for 
subsistence uses, and (2) the practicability of the measure(s) for 
applicant implementation.
    Subsistence harvest in Southeast Alaska is primarily focused on 
harbor seals, with occasional harvest of sea lions (Wolfe et al. 2013). 
To our knowledge, no whaling occurs in the NWTT Study Area. Testing 
activities in Western Behm Canal are the only activities within the 
NWTT Study Area that have the potential to overlap with subsistence 
uses of marine mammals.
    Four Alaskan Native communities are located in the Behm Canal area: 
Central Council of the Tlingit and Haida Indian Tribes, Ketchikan 
Indian Corporation, Organized Village of Saxman, and Metlakatla Indian 
Community, Annette Island Reserve.
    The Tlingit and Haida people retain a life that is strongly based 
on subsistence, including the use of harbor seals and sea lions for 
food and raw materials (Wolfe et al. 2013). Harbor seals are taken 
during all months; peak harvests occur during spring and during fall/
early winter. The lowest harvest occurs in the summer months (Wolfe et 
al. 2013). In most communities, hunters

[[Page 72457]]

use the waters and coastlines adjacent to their home to harvest seals, 
with travel ranging from 5 to 32.6 mi (8 to 52.5 km) (Davis 1999). 
While there is large overlap in the core use areas of the Ketchikan and 
Saxman communities, harvest of seals within Western Behm Canal is more 
common from the Ketchikan community (Davis 1999). Hunters from the 
Ketchikan community primarily take seals off Revillagigedo Island. They 
also harvest seals in areas north of Ketchikan into the northern mouth 
of Western Behm Canal near Betton Island (Davis, 1999). The Metlakatla 
Indian Community is located on Annette Island, in the Clarence Strait 
opposite of Ketchikan. NMFS is unaware of any harvest of harbor seals 
within Western Behm Canal from hunters in Metlakatla Indian Community.
    No information has been provided by these communities regarding how 
the Navy's activities may impact the availability of marine mammals for 
Alaskan Native subsistence uses. The Navy sent communications to the 
four tribes at both the regional and community level at multiple stages 
throughout the NWTT rulemaking and SEIS/OEIS processes, including an 
invitation to initiate government to government consultation. 
Additionally, the Installation Environmental Director for Naval Base 
Kitsap, who oversees natural resources management at the Navy's 
Southeast Alaska Acoustic Facility (SEAFAC), met with representatives 
from the Ketchikan Indian Corporation and the Organized Village of 
Saxman to discuss the Facility and its operations in March 2019. During 
this face to face meeting and tour of the facility, the Tribes did not 
raise concern regarding their ability to harvest marine mammals.
    In addition to these communications, the Navy followed up in April 
2020 with a specific request to the four communities for any concerns 
regarding potential impacts of the Navy's proposed activities in the 
Western Behm Canal on the availability of marine mammal species or 
stocks for Alaska Native subsistence use. The Navy again contacted the 
tribes in May 2020, following up on their request. To date, neither the 
Navy nor NMFS have received correspondence from Alaska Native groups 
regarding subsistence use, or any other concern with the MMPA 
rulemaking and authorizations.
    In Western Behm Canal, seals and sea lions are estimated to be 
taken by Level B harassment by behavioral disturbance and TTS only. 
Given the minor and temporary nature of the takes, and the temporary 
nature of the activity, we do not expect these impacts to cause the 
animals to avoid or abandon an area where subsistence harvest typically 
occurs.
    The Navy's testing area in Western Behm Canal includes five 
restricted areas (see Figure 2-4 in the Navy's rulemaking/LOA 
application); the largest, Area 5, spans the width of Western Behm 
Canal and encompasses Areas 1, 2, and 3. During operations, the Navy 
can close the restricted areas to all vessel traffic. Typically, such 
closures do not exceed 20 minutes. Public notifications (Notices to 
Mariners) announcing restricted access have been issued 10 times per 
year on average; about 8-12 events occur annually that require 
restrictions on vessel traffic to ensure that the Navy vessel (usually 
a submarine, which is out of the visual observation of small boat 
operators) has a clear sea space to navigate safely. Notices to 
Mariners usually extend for a period of four or five days, but 
limitations on vessel traffic typically last for 20 minutes and occur 
up to twice per hour. During these times, small vessels (30 ft or less) 
transiting through Western Behm Canal are required to stay within 1,000 
yd. of the shoreline, maintain a maximum speed of 5 knots, and be in 
radio contact with SEAFAC. The Navy uses the radio contact to ensure 
that all vessels comply with the navigation rules during these critical 
periods. On occasion, the engine of a transiting vessel may create 
noise that interferes with data collection during a test. When this 
occurs, SEAFAC may request that the vessel operator voluntarily turn 
off the engine during the period of data collection. Alternatively, 
SEAFAC may delay data collection until the vessel has cleared the area. 
When testing is not being conducted, vessel traffic is not restricted, 
but permanent restrictions on anchors, nets, towing, and dumping remain 
in force. Additional information on transiting the restricted areas in 
Western Behm Canal is provided in 33 CFR 334.1275 (Western Behm Canal, 
Ketchikan, Alaska, restricted areas).
    NMFS does not expect that these occasional 20-minute closures and 
associated restrictions will displace subsistence users, as the 
closures are limited, short term, and affect a limited portion of 
Western Behm Canal.
    The Notice to Mariners notifying government agencies and the public 
that the Navy will conduct operations and restrict access in Western 
Behm Canal will be provided at least 72 hours in advance to the Central 
Council of the Tlingit and Haida Indian Tribes, Ketchikan Indian 
Corporation, Organized Village of Saxman, and Metlakatla Indian 
Community, Annette Island Reserve, as well as the U.S. Coast Guard, 
Ketchikan Gateway Borough Planning Department, Harbor Master, Alaska 
Department of Fish and Game, KRBD radio, KTKN radio, and the Ketchikan 
Daily News.
    NMFS expects that subsistence harvest activities would most likely 
occur close to the shoreline along Betton Island, as well as some of 
the neighboring smaller islands (including Back Island), when receding 
tidal waters expose the shoreline, and animals haulout. There are no 
Navy activities that would create a physical barrier between 
subsistence users and marine mammals in nearshore areas. In the 
offshore area, the temporary presence of vessels (boats, submarines, 
etc.) and operational equipment needed to conduct the testing 
activities may block preferred navigational paths; however, the 
presence of vessels and equipment will be temporary, and easy to 
navigate around. Therefore, we do not expect the presence of these 
vessels and equipment to create a physical barrier between subsistence 
hunters and marine mammals.
    Further offshore within Western Behm Canal, the Navy has in-water 
structures which include two sites: the underway site and the static 
site, located in the five restricted areas discussed above. The 
underway site and static site are existing testing structures that are 
required for conducting testing operations. The in-water structures 
located at the underway site and static site are easy to navigate 
around, and we do not expect their presence to impact subsistence 
harvests.
    Overall, physical barriers associated with the Navy's activities 
will be limited to the temporary presence of additional vessels (boats, 
submarines, etc.) and other operational equipment needed to conduct the 
testing activities, including the reading of those vessels' acoustic 
signatures. Vessels will only be present temporarily and are easy to 
navigate around and avoid. Therefore, we do not expect the Navy's 
action to create a physical barrier that will limit the ability of 
subsistence harvest by Alaskan Natives.
    Based on NMFS having no information indicating that the Navy's 
activity in Western Behm Canal will affect Alaskan Native subsistence 
activities and the location and nature of the Navy's activity, NMFS has 
determined that the total taking of affected species or stocks will not 
have an unmitigable adverse impact on the availability of the species 
or stocks for taking for subsistence uses.

[[Page 72458]]

Classification

Endangered Species Act

    There are seven marine mammal species under NMFS jurisdiction that 
are listed as endangered or threatened under the ESA (16 U.S.C. 1531 et 
seq.) with confirmed or possible occurrence in the NWTT Study Area: 
blue whale, fin whale, humpback whale (Mexico and Central America 
DPSs), sei whale, sperm whale, killer whale (Southern Resident killer 
whale DPS), and Guadalupe fur seal. The Southern Resident killer whale 
has critical habitat designated under the ESA in the NWTT Study Area. 
On September 19, 2019, NMFS proposed to revise ESA-designated critical 
habitat for Southern Resident killer whales (84 FR 49214). In addition, 
on October 9, 2019, NMFS published a proposed rule to designate ESA 
critical habitat for the Central America, Mexico, and Western North 
Pacific DPSs of humpback whales (84 FR 54354). Neither ESA critical 
habitat rule has been finalized.
    The Navy consulted with NMFS pursuant to section 7 of the ESA for 
NWTT activities, and NMFS also consulted internally on the promulgation 
of this rule and the issuance of LOAs under section 101(a)(5)(A) of the 
MMPA. NMFS issued a biological opinion concluding that the promulgation 
of the rule and issuance of subsequent LOAs are not likely to 
jeopardize the continued existence of threatened and endangered species 
under NMFS' jurisdiction and are not likely to result in the 
destruction or adverse modification of designated or proposed critical 
habitat in the NWTT Study Area. The biological opinion is available at 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.

National Marine Sanctuaries Act

    Federal agency actions that are likely to injure sanctuary 
resources are subject to consultation with NOAA's Office of National 
Marine Sanctuaries (ONMS) under section 304(d) of the National Marine 
Sanctuaries Act (NMSA; 16 U.S.C. 1431 et seq.).
    On April 29, 2020, NMFS and the Navy jointly requested consultation 
with ONMS and submitted a Sanctuary Resource Statement (SRS), as the 
Navy concluded that their training and testing activities in the NWTT 
Study Area may incidentally expose sanctuary resources that reside 
within Olympic Coast National Marine Sanctuary (NMS) to sound and other 
environmental stressors, and NMFS concluded that proposed MMPA 
regulations and associated LOAs that would allow the Navy to 
incidentally take marine mammals include a subset of those impacts that 
could occur to NMS resources.
    After discussions with the ONMS, NMFS and the Navy submitted a 
revised SRS on July 8, 2020. ONMS reviewed the SRS, and on July 15, 
2020, ONMS found the SRS sufficient for the purposes of making an 
injury determination and developing recommended alternatives as 
required by the NMSA. On August 28, 2020, ONMS provided its injury 
determination and three recommended alternatives to minimize injury and 
to protect sanctuary resources. NMFS and the Navy submitted a joint 
response to the ONMS recommended alternatives. Consultation under the 
NMSA is now concluded.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must evaluate our proposed actions and alternatives with respect 
to potential impacts on the human environment. NMFS participated as a 
cooperating agency on the 2020 NWTT FSEIS/OEIS, which was published on 
September 18, 2020, and is available at https://nwtteis.com/. In 
accordance with 40 CFR 1506.3, NMFS independently reviewed and 
evaluated the 2020 NWTT FSEIS/OEIS and determined that it is adequate 
and sufficient to meet our responsibilities under NEPA for the issuance 
of this rule and associated LOAs. NOAA therefore, has adopted the 2020 
NWTT FSEIS/OEIS. NMFS has prepared a separate Record of Decision. NMFS' 
Record of Decision for adoption of the 2020 NWTT FSEIS/OEIS and 
issuance of this final rule and subsequent LOAs can be found at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.

Regulatory Flexibility Act

    The Office of Management and Budget has determined that this rule 
is not significant for purposes of Executive Order 12866.
    Pursuant to the Regulatory Flexibility Act (RFA; 5 U.S.C. 601 et 
seq.), the Chief Counsel for Regulation of the Department of Commerce 
has certified to the Chief Counsel for Advocacy of the Small Business 
Administration during the proposed rule stage that this action would 
not have a significant economic impact on a substantial number of small 
entities. The factual basis for the certification was published in the 
proposed rule and is not repeated here. No comments were received 
regarding this certification. As a result, a regulatory flexibility 
analysis was not required and none was prepared.

Waiver of Delay in Effective Date

    NMFS has determined that there is good cause under the 
Administrative Procedure Act (APA; 5 U.S.C. 553(d)(3)) to waive the 30-
day delay in the effective date of this final rule. No individual or 
entity other than the Navy is affected by the provisions of these 
regulations. The Navy has requested that this final rule take effect on 
or before November 9, 2020, to accommodate the Navy's LOAs that expire 
on November 8, 2020, so as to not cause a disruption in training and 
testing activities. The waiver of the 30-day delay of the effective 
date of the final rule will ensure that the MMPA final rule and LOAs 
are in place by the time the previous authorizations expire. Any delay 
in effectiveness of the final rule would result in either: (1) A 
suspension of planned naval training and testing, which would disrupt 
vital training and testing essential to national security; or (2) the 
Navy's procedural non-compliance with the MMPA (should the Navy conduct 
training and testing without LOAs), thereby resulting in the potential 
for unauthorized takes of marine mammals. Moreover, the Navy is ready 
to implement the regulations immediately. For these reasons, NMFS finds 
good cause to waive the 30-day delay in the effective date. In 
addition, the rule authorizes incidental take of marine mammals that 
would otherwise be prohibited under the statute. Therefore, by granting 
an exception to the Navy, the rule relieves restrictions under the 
MMPA, which provides a separate basis for waiving the 30-day effective 
date for the rule under section 553(d)(1) of the APA.

List of Subjects in 50 CFR Part 218

    Exports, Fish, Imports, Incidental take, Indians, Labeling, Marine 
mammals, Navy, Penalties, Reporting and recordkeeping requirements, 
Seafood, Sonar, Transportation.

    Dated: October 20, 2020.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.

    For reasons set forth in the preamble, 50 CFR part 218 is amended 
as follows:

[[Page 72459]]

PART 218--REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE 
MAMMALS

0
1. The authority citation for part 218 continues to read as follows:

    Authority: 16 U.S.C. 1361 et seq., unless otherwise noted.


0
2. Revise subpart O to part 218 to read as follows:
Subpart O--Taking and Importing Marine Mammals; U.S. Navy's Northwest 
Training and Testing (NWTT)
Sec.
218.140 Specified activity and geographical region.
218.141 Effective dates.
218.142 Permissible methods of taking.
218.143 Prohibitions.
218.144 Mitigation requirements.
218.145 Requirements for monitoring and reporting.
218.146 Letters of Authorization.
218.147 Renewals and modifications of Letters of Authorization.
218.148 [Reserved]

Subpart O--Taking and Importing Marine Mammals; U.S. Navy's 
Northwest Training and Testing (NWTT)


Sec.  218.140  Specified activity and geographical region.

    (a) Regulations in this subpart apply only to the U.S. Navy (Navy) 
for the taking of marine mammals that occurs in the area described in 
paragraph (b) of this section and that occurs incidental to the 
activities listed in paragraph (c) of this section.
    (b) The taking of marine mammals by the Navy under this subpart may 
be authorized in Letters of Authorization (LOAs) only if it occurs 
within the NWTT Study Area. The NWTT Study Area is composed of 
established maritime operating and warning areas in the eastern North 
Pacific Ocean region, including areas of the Strait of Juan de Fuca, 
Puget Sound, and Western Behm Canal in southeastern Alaska. The Study 
Area includes air and water space within and outside Washington state 
waters, and outside state waters of Oregon and Northern California. The 
eastern boundary of the Offshore Area portion of the Study Area is 12 
nautical miles (nmi) off the coastline for most of the Study Area 
starting south of W-237, including southern Washington, Oregon, and 
Northern California. The Offshore Area includes the ocean all the way 
to the coastline only along that part of the Washington coast that lies 
beneath the airspace of W-237 and the Olympic Military Operations Area. 
The Quinault Range Site is a defined area of sea space where training 
and testing is conducted. The Quinault Range Site coincides with the 
boundaries of W-237A and also includes a surf zone component. The surf 
zone component extends north to south 5 nmi along the eastern boundary 
of W-237A, extends approximately 3 nmi to shore along the mean lower 
low water line, and encompasses 1 mile (1.6 kilometers) of shoreline at 
Pacific Beach, Washington. The Study Area includes four existing range 
complexes and facilities: the Northwest Training Range Complex (NWTRC), 
the Keyport Range Complex, the Carr Inlet Operations Area, and the 
Southeast Alaska Acoustic Measurement Facility (SEAFAC). In addition to 
these range complexes, the Study Area also includes Navy pierside 
locations where sonar maintenance and testing occurs as part of 
overhaul, modernization, maintenance, and repair activities at Naval 
Base Kitsap, Bremerton; Naval Base Kitsap, Bangor; and Naval Station 
Everett.
    (c) The taking of marine mammals by the Navy is only authorized if 
it occurs incidental to the Navy conducting training and testing 
activities, including:
    (1) Anti-submarine warfare;
    (2) Mine warfare;
    (3) Surface warfare;
    (4) Unmanned systems;
    (5) Vessel evaluation; and
    (6) Other training and testing activities.


Sec.  218.141  Effective dates.

    Regulations in this subpart are effective from November 9, 2020, 
through November 8, 2027.


Sec.  218.142  Permissible methods of taking.

    (a) Under LOAs issued pursuant to Sec. Sec.  216.106 of this 
chapter and 218.146, the Holder of the LOAs (hereinafter ``Navy'') may 
incidentally, but not intentionally, take marine mammals within the 
area described in Sec.  218.140(b) by Level A harassment and Level B 
harassment associated with the use of active sonar and other acoustic 
sources and explosives, as well as serious injury or mortality 
associated with vessel strikes, provided the activity is in compliance 
with all terms, conditions, and requirements of this subpart and the 
applicable LOAs.
    (b) The incidental take of marine mammals by the activities listed 
in Sec.  218.140(c) is limited to the following species:

                        Table 1 to Paragraph (b)
------------------------------------------------------------------------
              Species                               Stock
------------------------------------------------------------------------
Blue whale........................  Eastern North Pacific.
Fin whale.........................  Northeast Pacific.
Fin whale.........................  California/Oregon/Washington.
Sei whale.........................  Eastern North Pacific.
Minke whale.......................  Alaska.
Minke whale.......................  California/Oregon/Washington.
Humpback whale....................  Central North Pacific.
Humpback whale....................  California/Oregon/Washington.
Gray whale........................  Eastern North Pacific.
Bottlenose dolphin................  California/Oregon/Washington
                                     Offshore.
Killer whale......................  Alaska Resident.
Killer whale......................  Eastern North Pacific Offshore.
Killer whale......................  West Coast Transient.
Killer whale......................  Southern Resident.
Northern right whale dolphin......  California/Oregon/Washington.
Pacific white-sided dolphin.......  North Pacific.
Pacific white-sided dolphin.......  California/Oregon/Washington.
Risso's dolphin...................  California/Oregon/Washington.
Short-beaked common dolphin.......  California/Oregon/Washington.
Short-finned pilot whale..........  California/Oregon/Washington.
Striped dolphin...................  California/Oregon/Washington.
Pygmy sperm whale.................  California/Oregon/Washington.
Dwarf sperm whale.................  California/Oregon/Washington.

[[Page 72460]]

 
Dall's porpoise...................  Alaska.
Dall's porpoise...................  California/Oregon/Washington.
Harbor porpoise...................  Southeast Alaska.
Harbor porpoise...................  Northern Oregon & Washington Coast.
Harbor porpoise...................  Northern California/Southern Oregon.
Harbor porpoise...................  Washington Inland Waters.
Sperm whale.......................  California/Oregon/Washington.
Baird's beaked whale..............  California/Oregon/Washington.
Cuvier's beaked whale.............  California/Oregon/Washington.
Mesoplodon species................  California/Oregon/Washington.
California sea lion...............  U.S. Stock.
Steller sea lion..................  Eastern U.S.
Guadalupe fur seal................  Mexico.
Northern fur seal.................  Eastern Pacific.
Northern fur seal.................  California.
Harbor seal.......................  Southeast Alaska--Clarence Strait.
Harbor seal.......................  Oregon & Washington Coastal.
Harbor seal.......................  Washington Northern Inland Waters.
Harbor seal.......................  Hood Canal.
Harbor seal.......................  Southern Puget Sound.
Northern elephant seal............  California.
------------------------------------------------------------------------

Sec.  218.143  Prohibitions.

    (a) Notwithstanding incidental takings contemplated in Sec.  
218.142(a) and authorized by LOAs issued under Sec. Sec.  216.106 of 
this chapter and 218.146, no person in connection with the activities 
listed in Sec.  218.140(c) may:
    (1) Violate, or fail to comply with, the terms, conditions, and 
requirements of this subpart or an LOA issued under Sec. Sec.  216.106 
of this chapter and 218.146;
    (2) Take any marine mammal not specified in Sec.  218.142(b);
    (3) Take any marine mammal specified in Sec.  218.142(b) in any 
manner other than as specified in the LOAs; or
    (4) Take a marine mammal specified in Sec.  218.142(b) if NMFS 
determines such taking results in more than a negligible impact on the 
species or stock of such marine mammal.
    (b) [Reserved]


Sec.  218.144  Mitigation requirements.

    (a) When conducting the activities identified in Sec.  218.140(c), 
the mitigation measures contained in any LOAs issued under Sec. Sec.  
216.106 of this chapter and 218.146 must be implemented. These 
mitigation measures include, but are not limited to:
    (1) Procedural mitigation. Procedural mitigation is mitigation that 
the Navy must implement whenever and wherever an applicable training or 
testing activity takes place within the NWTT Study Area for each 
applicable activity category or stressor category and includes acoustic 
stressors (i.e., active sonar, weapons firing noise), explosive 
stressors (i.e., sonobuoys, torpedoes, medium-caliber and large-caliber 
projectiles, missiles, bombs, Mine Countermeasure and Neutralization 
activities, mine neutralization involving Navy divers), and physical 
disturbance and strike stressors (i.e., vessel movement, towed in-water 
devices, small-, medium-, and large-caliber non-explosive practice 
munitions, non-explosive missiles, non-explosive bombs and mine 
shapes).
    (i) Environmental awareness and education. Appropriate Navy 
personnel (including civilian personnel) involved in mitigation and 
training or testing activity reporting under the specified activities 
will complete the environmental compliance training modules identified 
in their career path training plan, as specified in the LOAs.
    (ii) Active sonar. Active sonar includes low-frequency active 
sonar, mid-frequency active sonar, and high-frequency active sonar. For 
vessel-based active sonar activities, mitigation applies only to 
sources that are positively controlled and deployed from manned surface 
vessels (e.g., sonar sources towed from manned surface platforms). For 
aircraft-based active sonar activities, mitigation applies only to 
sources that are positively controlled and deployed from manned 
aircraft that do not operate at high altitudes (e.g., rotary-wing 
aircraft). Mitigation does not apply to active sonar sources deployed 
from unmanned aircraft or aircraft operating at high altitudes (e.g., 
maritime patrol aircraft).
    (A) Number of Lookouts and observation platform for hull-mounted 
sources. For hull-mounted sources, the Navy must have one Lookout for 
platforms with space or manning restrictions while underway (at the 
forward part of a small boat or ship) and platforms using active sonar 
while moored or at anchor (including pierside), and two Lookouts for 
platforms without space or manning restrictions while underway (at the 
forward part of the ship).
    (B) Number of Lookouts and observation platform for sources not 
hull-mounted. For sources that are not hull-mounted, the Navy must have 
one Lookout on the ship or aircraft conducting the activity.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., when maneuvering on station), Navy personnel must observe the 
mitigation zone for floating vegetation and marine mammals; if floating 
vegetation or a marine mammal is observed, Navy personnel must relocate 
or delay the start of active sonar transmission until the mitigation 
zone is clear of floating vegetation or until the conditions in 
paragraph (a)(1)(ii)(F) are met for marine mammals.
    (D) During activity for low-frequency active sonar at 200 decibels 
(dB) and hull-mounted mid-frequency active sonar. During the activity, 
for low-frequency active sonar at 200 dB and hull-mounted mid-frequency 
active sonar, Navy personnel must observe the following mitigation 
zones for marine mammals.
    (1) Powerdowns for marine mammals. Navy personnel must power down 
active sonar transmission by 6 dB if marine mammals are observed within 
1,000 yard (yd) of the sonar source; Navy personnel must power down an 
additional 4 dB (10 dB total) if marine mammals are observed within 500 
yd of the sonar source.

[[Page 72461]]

    (2) Shutdowns for marine mammals. Navy personnel must cease 
transmission if cetaceans are observed within 200 yd of the sonar 
source in any location in the Study Area; Navy personnel must cease 
transmission if pinnipeds in the NWTT Offshore Area or Western Behm 
Canal are observed within 200 yd of the sonar source and cease 
transmission if pinnipeds in NWTT Inland Waters are observed within 100 
yd of the sonar source (except if hauled out on, or in the water near, 
man-made structures and vessels).
    (E) During activity for low-frequency active sonar below 200 dB, 
mid-frequency active sonar not hull-mounted, and high-frequency sonar. 
During the activity, for low-frequency active sonar below 200 dB, mid-
frequency active sonar sources that are not hull-mounted, and high-
frequency sonar, Navy personnel must observe the following mitigation 
zones for marine mammals. Navy personnel must cease transmission if 
cetaceans are observed within 200 yd of the sonar source in any 
location in the Study Area. Navy personnel must cease transmission if 
pinnipeds in the NWTT Offshore Area or Western Behm Canal are observed 
within 200 yd of the sonar source. Navy personnel must cease 
transmission if pinnipeds in NWTT Inland Waters are observed within 100 
yd of the sonar source (except if hauled out on, or in the water near, 
man-made structures and vessels).
    (F) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
marine mammal to leave the mitigation zone prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing or powering up active sonar transmission) until one of the 
following conditions has been met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the sonar source;
    (3) Clear from additional sightings. The mitigation zone has been 
clear from any additional sightings for 10 minutes (min) for aircraft-
deployed sonar sources or 30 min for vessel-deployed sonar sources;
    (4) Sonar source transit. For mobile activities, the active sonar 
source has transited a distance equal to double that of the mitigation 
zone size beyond the location of the last sighting; or
    (5) Bow-riding dolphins. For activities using hull-mounted sonar, 
the Lookout concludes that dolphins are deliberately closing in on the 
ship to ride the ship's bow wave, and are therefore out of the main 
transmission axis of the sonar (and there are no other marine mammal 
sightings within the mitigation zone).
    (iii) Weapons firing noise. Weapons firing noise associated with 
large-caliber gunnery activities.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned on the ship conducting the firing. Depending on the 
activity, the Lookout could be the same as the one described for 
``Explosive medium-caliber and large-caliber projectiles'' or for 
``Small-, medium-, and large-caliber non-explosive practice munitions'' 
in paragraphs (a)(1)(vi)(A) and (a)(1)(xiii)(A) of this section.
    (B) Mitigation zone. Thirty degrees on either side of the firing 
line out to 70 yd from the muzzle of the weapon being fired.
    (C) Prior to activity. Prior to the initial start of the activity, 
Navy personnel must observe the mitigation zone for floating vegetation 
and marine mammals; if floating vegetation or a marine mammal is 
observed, Navy personnel must relocate or delay the start of weapons 
firing until the mitigation zone is clear of floating vegetation or 
until the conditions in paragraph (a)(1)(iii)(E) of this section are 
met for marine mammals.
    (D) During activity. During the activity, Navy personnel must 
observe the mitigation zone for marine mammals; if marine mammals are 
observed, Navy personnel must cease weapons firing.
    (E) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
marine mammal to leave the mitigation zone prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing weapons firing) until one of the following conditions has 
been met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the firing ship;
    (3) Clear from additional sightings. The mitigation zone has been 
clear from any additional sightings for 30 min; or
    (4) Firing ship transit. For mobile activities, the firing ship has 
transited a distance equal to double that of the mitigation zone size 
beyond the location of the last sighting.
    (iv) Explosive sonobuoys.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned in an aircraft or on a small boat. If additional 
platforms are participating in the activity, Navy personnel positioned 
in those assets (e.g., safety observers, evaluators) must support 
observing the mitigation zone for applicable biological resources, 
including marine mammals, while performing their regular duties.
    (B) Mitigation zone. 600 yd around an explosive sonobuoy.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., during deployment of a sonobuoy field, which typically lasts 20-
30 min), Navy personnel must conduct passive acoustic monitoring for 
marine mammals; personnel must use information from detections to 
assist visual observations. Navy personnel also must visually observe 
the mitigation zone for floating vegetation and marine mammals; if 
floating vegetation or a marine mammal is observed, Navy personnel must 
relocate or delay the start of sonobuoy or source/receiver pair 
detonations until the mitigation zone is clear of floating vegetation 
or until the conditions in paragraph (a)(1)(iv)(E) of this section are 
met for marine mammals.
    (D) During activity. During the activity, Navy personnel must 
observe the mitigation zone for marine mammals; if marine mammals are 
observed, Navy personnel must cease sonobuoy or source/receiver pair 
detonations.
    (E) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
marine mammal to leave the mitigation zone prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing detonations) until one of the following conditions has 
been met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the sonobuoy; or
    (3) Clear from additional sightings. The mitigation zone has been 
clear from any additional sightings for 10 min when the activity 
involves aircraft that have fuel constraints, or 30 min when the 
activity involves aircraft that are not typically fuel constrained.
    (F) After activity. After completion of the activity (e.g., prior 
to maneuvering off station), Navy personnel must, when practical (e.g., 
when platforms are not constrained by fuel restrictions or

[[Page 72462]]

mission-essential follow-on commitments), observe for marine mammals in 
the vicinity of where detonations occurred; if any injured or dead 
marine mammals are observed, Navy personnel must follow established 
incident reporting procedures. If additional platforms are supporting 
this activity (e.g., providing range clearance), Navy personnel on 
these assets must assist in the visual observation of the area where 
detonations occurred.
    (v) Explosive torpedoes.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned in an aircraft. If additional platforms are participating 
in the activity, Navy personnel positioned in those assets (e.g., 
safety observers, evaluators) must support observing the mitigation 
zone for applicable biological resources, including marine mammals, 
while performing their regular duties.
    (B) Mitigation zone. 2,100 yd around the intended impact location.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., during deployment of the target), Navy personnel must conduct 
passive acoustic monitoring for marine mammals; personnel must use the 
information from detections to assist visual observations. Navy 
personnel also must visually observe the mitigation zone for floating 
vegetation and marine mammals; if floating vegetation or a marine 
mammal is observed, Navy personnel must relocate or delay the start of 
firing until the mitigation zone is clear of floating vegetation or 
until the conditions in paragraph (a)(1)(v)(E) of this section are met 
for marine mammals.
    (D) During activity. During the activity, Navy personnel must 
observe the mitigation zone for marine mammals; if marine mammals are 
observed, Navy personnel must cease firing.
    (E) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
marine mammal to leave the mitigation zone prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing firing) until one of the following conditions has been 
met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the intended impact location; or
    (3) Clear from additional sightings. The mitigation zone has been 
clear from any additional sightings for 10 min when the activity 
involves aircraft that have fuel constraints, or 30 min when the 
activity involves aircraft that are not typically fuel constrained.
    (F) After activity. After completion of the activity (e.g., prior 
to maneuvering off station), Navy personnel must, when practical (e.g., 
when platforms are not constrained by fuel restrictions or mission-
essential follow-on commitments), observe for marine mammals in the 
vicinity of where detonations occurred; if any injured or dead marine 
mammals are observed, Navy personnel must follow established incident 
reporting procedures. If additional platforms are supporting this 
activity (e.g., providing range clearance), Navy personnel on these 
assets must assist in the visual observation of the area where 
detonations occurred.
    (vi) Explosive medium-caliber and large-caliber projectiles. 
Gunnery activities using explosive medium-caliber and large-caliber 
projectiles. Mitigation applies to activities using a surface target.
    (A) Number of Lookouts and observation platform. One Lookout must 
be on the vessel conducting the activity. For activities using 
explosive large-caliber projectiles, depending on the activity, the 
Lookout could be the same as the one described for ``Weapons firing 
noise'' in paragraph (a)(1)(iii)(A) of this section. If additional 
platforms are participating in the activity, Navy personnel positioned 
in those assets (e.g., safety observers, evaluators) must support 
observing the mitigation zone for applicable biological resources, 
including marine mammals, while performing their regular duties.
    (B) Mitigation zones. 600 yd around the intended impact location 
for explosive medium-caliber projectiles. 1,000 yd around the intended 
impact location for explosive large-caliber projectiles.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., when maneuvering on station), Navy personnel must observe the 
mitigation zone for floating vegetation and marine mammals; if floating 
vegetation or a marine mammal is observed, Navy personnel must relocate 
or delay the start of firing until the mitigation zone is clear of 
floating vegetation or until the conditions in paragraph (a)(1)(vi)(E) 
of this section are met for marine mammals.
    (D) During activity. During the activity, Navy personnel must 
observe the mitigation zone for marine mammals; if marine mammals are 
observed, Navy personnel must cease firing.
    (E) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
marine mammal to leave the mitigation zone prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing firing) until one of the following conditions has been 
met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the intended impact location;
    (3) Clear of additional sightings. The mitigation zone has been 
clear from any additional sightings for 30 min for vessel-based firing; 
or
    (4) Impact location transit. For activities using mobile targets, 
the intended impact location has transited a distance equal to double 
that of the mitigation zone size beyond the location of the last 
sighting.
    (F) After activity. After completion of the activity (e.g., prior 
to maneuvering off station), Navy personnel must, when practical (e.g., 
when platforms are not constrained by fuel restrictions or mission-
essential follow-on commitments), observe for marine mammals in the 
vicinity of where detonations occurred; if any injured or dead marine 
mammals are observed, Navy personnel must follow established incident 
reporting procedures. If additional platforms are supporting this 
activity (e.g., providing range clearance), Navy personnel on these 
assets must assist in the visual observation of the area where 
detonations occurred.
    (vii) Explosive missiles. Aircraft-deployed explosive missiles. 
Mitigation applies to activities using a surface target.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned in an aircraft. If additional platforms are participating 
in the activity, Navy personnel positioned in those assets (e.g., 
safety observers, evaluators) must support observing the mitigation 
zone for applicable biological resources, including marine mammals, 
while performing their regular duties.
    (B) Mitigation zone. 2,000 yd around the intended impact location.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., during a fly-over of the mitigation zone), Navy personnel must 
observe the mitigation zone for floating vegetation and marine mammals; 
if floating vegetation or a marine mammal is observed, Navy personnel 
must relocate or delay the

[[Page 72463]]

start of firing until the mitigation zone is clear of floating 
vegetation or until the conditions in paragraph (a)(1)(vii)(E) of this 
section are met for marine mammals.
    (D) During activity. During the activity, Navy personnel must 
observe the mitigation zone for marine mammals; if marine mammals are 
observed, Navy personnel must cease firing.
    (E) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
marine mammal to leave the mitigation zone prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing firing) until one of the following conditions has been 
met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the intended impact location; or
    (3) Clear of additional sightings. The mitigation zone has been 
clear from any additional sightings for 10 min when the activity 
involves aircraft that have fuel constraints, or 30 min when the 
activity involves aircraft that are not typically fuel constrained.
    (F) After activity. After completion of the activity (e.g., prior 
to maneuvering off station), Navy personnel must, when practical (e.g., 
when platforms are not constrained by fuel restrictions or mission-
essential follow-on commitments), observe for marine mammals in the 
vicinity of where detonations occurred; if any injured or dead marine 
mammals are observed, Navy personnel must follow established incident 
reporting procedures. If additional platforms are supporting this 
activity (e.g., providing range clearance), Navy personnel on these 
assets must assist in the visual observation of the area where 
detonations occurred.
    (viii) Explosive bombs.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned in an aircraft conducting the activity. If additional 
platforms are participating in the activity, Navy personnel positioned 
in those assets (e.g., safety observers, evaluators) must support 
observing the mitigation zone for applicable biological resources, 
including marine mammals, while performing their regular duties.
    (B) Mitigation zone. 2,500 yd around the intended target.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., when arriving on station), Navy personnel must observe the 
mitigation zone for floating vegetation and marine mammals; if floating 
vegetation or a marine mammals is observed, Navy personnel must 
relocate or delay the start of bomb deployment until the mitigation 
zone is clear of floating vegetation or until the conditions in 
paragraph (a)(1)(viii)(E) of this section are met for marine mammals.
    (D) During activity. During the activity (e.g., during target 
approach), Navy personnel must observe the mitigation zone for marine 
mammals; if marine mammals are observed, Navy personnel must cease bomb 
deployment.
    (E) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
marine mammal to leave the mitigation zone prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing bomb deployment) until one of the following conditions has 
been met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the intended target;
    (3) Clear from additional sightings. The mitigation zone has been 
clear from any additional sightings for 10 min; or
    (4) Intended target transit. For activities using mobile targets, 
the intended target has transited a distance equal to double that of 
the mitigation zone size beyond the location of the last sighting.
    (F) After activity. After completion of the activity (e.g., prior 
to maneuvering off station), Navy personnel must, when practical (e.g., 
when platforms are not constrained by fuel restrictions or mission-
essential follow-on commitments), observe for marine mammals in the 
vicinity of where detonations occurred; if any injured or dead marine 
mammals are observed, Navy personnel must follow established incident 
reporting procedures. If additional platforms are supporting this 
activity (e.g., providing range clearance), Navy personnel on these 
assets must assist in the visual observation of the area where 
detonations occurred.
    (ix) Explosive Mine Countermeasure and Neutralization activities.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned on a vessel or in an aircraft when implementing the 
smaller mitigation zone. Two Lookouts must be positioned (one in an 
aircraft and one on a small boat) when implementing the larger 
mitigation zone. If additional platforms are participating in the 
activity, Navy personnel positioned in those assets (e.g., safety 
observers, evaluators) must support observing the mitigation zone for 
applicable biological resources, including marine mammals, while 
performing their regular duties.
    (B) Mitigation zones. 600 yd around the detonation site for 
activities using <=5 lb net explosive weight. 2,100 yd around the 
detonation site for activities using >5-60 lb net explosive weight.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., when maneuvering on station; typically, 10 min when the activity 
involves aircraft that have fuel constraints, or 30 min when the 
activity involves aircraft that are not typically fuel constrained), 
Navy personnel must observe the mitigation zone for floating vegetation 
and marine mammals; if floating vegetation or a marine mammal is 
observed, Navy personnel must relocate or delay the start of 
detonations until the mitigation zone is clear of floating vegetation 
or until the conditions in paragraph (a)(1)(ix)(E) are met for marine 
mammals.
    (D) During activity. During the activity, Navy personnel must 
observe the mitigation zone for marine mammals; if marine mammals are 
observed, Navy personnel must cease detonations. Navy personnel must 
use the smallest practicable charge size for each activity. Navy 
personnel must conduct activities in daylight hours only and in 
Beaufort Sea state number 3 conditions or less.
    (E) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
marine mammal to leave the mitigation zone prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing detonations) until one of the following conditions has 
been met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the detonation site; or
    (3) Clear from additional sightings. The mitigation zone has been 
clear from any additional sightings for 10 min when the activity 
involves aircraft that have fuel constraints, or 30 min when the 
activity involves aircraft that are not typically fuel constrained.
    (F) After activity. After completion of the activity (typically 10 
min when the

[[Page 72464]]

activity involves aircraft that have fuel constraints, or 30 min when 
the activity involves aircraft that are not typically fuel 
constrained), Navy personnel must observe for marine mammals in the 
vicinity of where detonations occurred; if any injured or dead marine 
mammals are observed, Navy personnel must follow established incident 
reporting procedures. If additional platforms are supporting this 
activity (e.g., providing range clearance), Navy personnel on these 
assets must assist in the visual observation of the area where 
detonations occurred.
    (x) Explosive mine neutralization activities involving Navy divers.
    (A) Number of Lookouts and observation platform.
    (1) Lookouts on small boats. Two Lookouts on two small boats with 
one Lookout each, one of which must be a Navy biologist.
    (2) Divers. All divers placing the charges on mines must support 
the Lookouts while performing their regular duties and report 
applicable sightings to the lead Lookout, the supporting small boat, or 
the Range Safety Officer.
    (3) Additional platforms. If additional platforms are participating 
in the activity, Navy personnel positioned in those assets (e.g., 
safety observers, evaluators) must support observing the mitigation 
zone for applicable biological resources, including marine mammals, 
while performing their regular duties.
    (B) Mitigation zone. 500 yd around the detonation site during 
activities using > 0.5-2.5 lb net explosive weight.
    (C) Prior to activity. Prior to the initial start of the activity 
(starting 30 min before the first planned detonation), Navy personnel 
must observe the mitigation zone for floating vegetation and marine 
mammals; if floating vegetation or a marine mammal is observed, Navy 
personnel must relocate or delay the start of detonations until the 
mitigation zone is clear of floating vegetation or until the conditions 
in paragraph (a)(1)(x)(E) are met for marine mammals. A Navy biologist 
must serve as the lead Lookout and must make the final determination 
that the mitigation zone is clear of any floating vegetation or marine 
mammals, prior to the commencement of a detonation. The Navy biologist 
must maintain radio communication with the unit conducting the event 
and the other Lookout.
    (D) During activity. During the activity, Navy personnel must 
observe the mitigation zone for marine mammals; if marine mammals are 
observed, Navy personnel must cease detonations. To the maximum extent 
practicable depending on mission requirements, safety, and 
environmental conditions, Navy personnel must position boats near the 
midpoint of the mitigation zone radius (but outside of the detonation 
plume and human safety zone), must position themselves on opposite 
sides of the detonation location, and must travel in a circular pattern 
around the detonation location with one Lookout observing inward toward 
the detonation site and the other observing outward toward the 
perimeter of the mitigation zone. Navy personnel must only use 
positively controlled charges (i.e., no time-delay fuses). Navy 
personnel must use the smallest practicable charge size for each 
activity. All activities must be conducted in Beaufort sea state number 
2 conditions or better and must not be conducted in low visibility 
conditions.
    (E) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
animal to leave the mitigation zone prior to the initial start of the 
activity (by delaying the start to ensure the mitigation zone is clear 
for 30 min) or during the activity (by not recommencing detonations) 
until one of the following conditions has been met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the detonation site; or
    (3) Clear from additional sightings. The mitigation zone has been 
clear from any additional sightings for 30 min.
    (F) After activity. After each detonation and completion of an 
activity, the Navy must observe for marine mammals for 30 min in the 
vicinity of where detonations occurred and immediately downstream of 
the detonation location; if any injured or dead marine mammals are 
observed, Navy personnel must follow established incident reporting 
procedures. If additional platforms are supporting this activity (e.g., 
providing range clearance), Navy personnel on these assets must assist 
in the visual observation of the area where detonations occurred.
    (xi) Vessel movement. The mitigation will not be applied if: The 
vessel's safety is threatened; the vessel is restricted in its ability 
to maneuver (e.g., during launching and recovery of aircraft or landing 
craft, during towing activities, when mooring, and during Transit 
Protection Program exercises or other events involving escort vessels); 
the vessel is submerged or operated autonomously; or when impractical 
based on mission requirements (e.g., during test body retrieval by 
range craft).
    (A) Number of Lookouts and observation platform. One Lookout must 
be on the vessel that is underway.
    (B) Mitigation zones.
    (1) Whales. 500 yd around whales.
    (2) Marine mammals other than whales: Surface vessels. 200 yd 
around marine mammals other than whales (except bow-riding dolphins and 
pinnipeds hauled out on man-made navigational structures, port 
structures, and vessels) for surface vessels (which do not include 
small boats).
    (3) Marine mammals other than whales: Small boats. 100 yd around 
marine mammals other than whales (except bow-riding dolphins and 
pinnipeds hauled out on man-made navigational structures, port 
structures, and vessels) for small boats, such as range craft.
    (C) During activity. When underway, Navy personnel must observe the 
mitigation zone for marine mammals; if marine mammals are observed, 
Navy personnel must maneuver to maintain distance.
    (D) Incident reporting procedures. If a marine mammal vessel strike 
occurs, Navy personnel must follow the established incident reporting 
procedures.
    (xii) Towed in-water devices. Mitigation applies to devices that 
are towed from a manned surface platform or manned aircraft, or when a 
manned support craft is already participating in an activity involving 
in-water devices being towed by unmanned platforms. The mitigation will 
not be applied if the safety of the towing platform or in-water device 
is threatened.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned on a manned towing platform or support craft.
    (B) Mitigation zones.
    (1) Mitigation zone: In-water devices towed by aircraft or surface 
ships. 250 yd around marine mammals (except bow-riding dolphins and 
pinnipeds hauled out on man-made navigational structures, port 
structures, and vessels) for in-water devices towed by aircraft or 
surface ships.
    (2) Mitigation zone: In-water devices towed by small boats. 100 yd 
around marine mammals (except bow-riding dolphins and pinnipeds hauled 
out on man-made navigational structures, port structures, and vessels) 
for in-water devices towed by small boats, such as range craft.
    (C) During activity. During the activity (i.e., when towing an in-
water device), Navy personnel must observe the

[[Page 72465]]

mitigation zone for marine mammals; if marine mammals are observed, 
Navy personnel must maneuver to maintain distance.
    (xiii) Small-, medium-, and large-caliber non-explosive practice 
munitions. Gunnery activities using small-, medium-, and large-caliber 
non-explosive practice munitions. Mitigation applies to activities 
using a surface target.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned on the platform conducting the activity. Depending on the 
activity, the Lookout could be the same as the one described for 
``Weapons firing noise'' in paragraph (a)(1)(iii)(A) of this section.
    (B) Mitigation zone. 200 yd around the intended impact location.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., when maneuvering on station), Navy personnel must observe the 
mitigation zone for floating vegetation and marine mammals; if floating 
vegetation or a marine mammal is observed, Navy personnel must relocate 
or delay the start until the mitigation zone is clear of floating 
vegetation or until the conditions in paragraph (a)(1)(xiii)(E) are met 
for marine mammals.
    (D) During activity. During the activity, Navy personnel must 
observe the mitigation zone for marine mammals; if marine mammals are 
observed, Navy personnel must cease firing.
    (E) Commencement/recommencement conditions after marine mammal 
sighting before or during activity. Navy personnel must allow a sighted 
marine mammal to leave the mitigation zone prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing firing) until one of the following conditions has been 
met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the intended impact location;
    (3) Clear of additional sightings. The mitigation zone has been 
clear from any additional sightings for 10 min for aircraft-based 
firing or 30 min for vessel-based firing; or
    (4) Impact location transit. For activities using a mobile target, 
the intended impact location has transited a distance equal to double 
that of the mitigation zone size beyond the location of the last 
sighting.
    (xiv) Non-explosive missiles. Aircraft-deployed non-explosive 
missiles. Mitigation applies to activities using a surface target.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned in an aircraft.
    (B) Mitigation zone. 900 yd around the intended impact location.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., during a fly-over of the mitigation zone), Navy personnel must 
observe the mitigation zone for floating vegetation and marine mammals; 
if floating vegetation or a marine mammal is observed, Navy personnel 
must relocate or delay the start of firing until the mitigation zone is 
clear of floating vegetation or until the conditions in paragraph 
(a)(1)(xiv)(E) of this section are met for marine mammals.
    (D) During activity. During the activity, Navy personnel must 
observe the mitigation zone for marine mammals; if marine mammals are 
observed, Navy personnel must cease firing.
    (E) Commencement/recommencement conditions after marine mammal 
sighting prior to or during activity. Navy personnel must allow a 
sighted marine mammal to leave the mitigation zone prior to the initial 
start of the activity (by delaying the start) or during the activity 
(by not recommencing firing) until one of the following conditions has 
been met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the intended impact location; or
    (3) Clear from additional sightings. The mitigation zone has been 
clear from any additional sightings for 10 min when the activity 
involves aircraft that have fuel constraints, or 30 min when the 
activity involves aircraft that are not typically fuel constrained.
    (xv) Non-explosive bombs and mine shapes. Non-explosive bombs and 
non-explosive mine shapes during mine laying activities.
    (A) Number of Lookouts and observation platform. One Lookout must 
be positioned in an aircraft.
    (B) Mitigation zone. 1,000 yd around the intended target.
    (C) Prior to activity. Prior to the initial start of the activity 
(e.g., when arriving on station), Navy personnel must observe the 
mitigation zone for floating vegetation and marine mammals; if floating 
vegetation or a marine mammal is observed, Navy personnel must relocate 
or delay the start of bomb deployment or mine laying until the 
mitigation zone is clear of floating vegetation or until the conditions 
in paragraph (a)(1)(xv)(E) of this section are met for marine mammals.
    (D) During activity. During the activity (e.g., during approach of 
the target or intended minefield location), Navy personnel must observe 
the mitigation zone for marine mammals; if marine mammals are observed, 
Navy personnel must cease bomb deployment or mine laying.
    (E) Commencement/recommencement conditions after marine mammal 
sighting prior to or during activity. Navy personnel must allow a 
sighted marine mammal to leave the mitigation zone prior to the initial 
start of the activity (by delaying the start) or during the activity 
(by not recommencing bomb deployment or mine laying) until one of the 
following conditions has been met:
    (1) Observed exiting. The animal is observed exiting the mitigation 
zone;
    (2) Thought to have exited. The animal is thought to have exited 
the mitigation zone based on a determination of its course, speed, and 
movement relative to the intended target or minefield location;
    (3) Clear from additional sightings. The mitigation zone has been 
clear from any additional sightings for 10 min; or
    (4) Intended target transit. For activities using mobile targets, 
the intended target has transited a distance equal to double that of 
the mitigation zone size beyond the location of the last sighting.
    (2) Mitigation areas. In addition to procedural mitigation, Navy 
personnel must implement mitigation measures within mitigation areas to 
avoid or reduce potential impacts on marine mammals.
    (i) Marine Species Coastal Mitigation Area (year round unless 
specified as seasonal).
    (A) Within 50 nmi from shore in the Marine Species Coastal 
Mitigation Area.
    (1) Prohibited activities. The Navy must not conduct: Explosive 
training activities; explosive testing activities (with the exception 
of explosive Mine Countermeasure and Neutralization Testing 
activities); and non-explosive missile training activities.
    (2) Seasonal awareness notification messages. The Navy must issue 
annual seasonal awareness notification messages to alert Navy ships and 
aircraft to the possible presence of increased concentrations of 
Southern Resident killer whales from December 1 to June 30, humpback 
whales from May 1 to December 31, and gray whales from May 1 to 
November 30. For safe navigation

[[Page 72466]]

and to avoid interactions with large whales, the Navy must instruct 
vessels to remain vigilant to the presence of Southern Resident killer 
whales, humpback whales, and gray whales that may be vulnerable to 
vessel strikes or potential impacts from training and testing 
activities. Platforms must use the information from the awareness 
notification messages to assist their visual observation of applicable 
mitigation zones during training and testing activities and to aid in 
the implementation of procedural mitigation.
    (B) Within 20 nmi from shore in the Marine Species Coastal 
Mitigation Area.
    (1) Surface ship hull-mounted MF1 mid-frequency active sonar. The 
Navy must not conduct more than a total of 33 hours of surface ship 
hull-mounted MF1 mid-frequency active sonar during testing annually 
within 20 nmi from shore in the Marine Species Coastal Mitigation Area, 
in the Juan de Fuca Eddy Marine Species Mitigation Area, and in the 
Olympic Coast National Marine Sanctuary Mitigation Area combined.
    (2) Mine Countermeasure and Neutralization Testing from July 1 to 
September 30. To the maximum extent practical, the Navy must conduct 
explosive Mine Countermeasure and Neutralization Testing from July 1 to 
September 30 when operating within 20 nmi from shore.
    (3) Mine Countermeasure and Neutralization Testing from October 1 
to June 30. From October 1 to June 30, the Navy must not conduct more 
than one explosive Mine Countermeasure and Neutralization Testing 
event, not to exceed the use of 20 explosives from bin E4 and 3 
explosives from bin E7 annually, and not to exceed the use of 60 
explosives from bin E4 and 9 explosives from bin E7 over the seven-year 
period of the rule.
    (4) Large-caliber gunnery training activities and non-explosive 
bombing training. The Navy must not conduct non-explosive large-caliber 
gunnery training activities and non-explosive bombing training 
activities.
    (C) Within 12 nmi from shore in the Marine Species Coastal 
Mitigation Area.
    (1) Anti-submarine warfare tracking exercise--helicopter,--maritime 
patrol aircraft,--ship, or--submarine training and anti-submarine 
warfare torpedo exercise--submarine training. The Navy must not conduct 
Anti-Submarine Warfare Tracking Exercise--Helicopter,--Maritime Patrol 
Aircraft,--Ship, or--Submarine training activities (which involve the 
use of mid-frequency or high-frequency active sonar) or non-explosive 
Anti-Submarine Warfare Torpedo Exercise--Submarine training activities 
(which involve the use of mid-frequency or high-frequency active 
sonar).
    (2) Unmanned Underwater Vehicle Training. The Navy must not conduct 
more than one Unmanned Underwater Vehicle Training event within 12 nmi 
from shore at the Quinault Range Site. In addition, Unmanned Underwater 
Vehicle Training events within 12 nmi from shore at the Quinault Range 
Site must be cancelled or moved to another training location if 
Southern Resident killer whales are detected at the planned training 
location during the event planning process, or immediately prior to the 
event, as applicable.
    (3) Explosive use during Mine Countermeasure and Neutralization 
testing. During explosive Mine Countermeasure and Neutralization 
Testing, the Navy must not use explosives in bin E7 closer than 6 nmi 
from shore in the Quinault Range Site.
    (4) Non-explosive small- and medium-caliber gunnery training. The 
Navy must not conduct non-explosive small- and medium-caliber gunnery 
training activities.
    (D) National security exception. Should national security require 
that the Navy cannot comply with the restrictions in paragraphs 
(a)(2)(i)(A)(1); (a)(2)(i)(B); or (a)(2)(i)(C) of this section, Navy 
personnel must obtain permission from the appropriate designated 
Command authority prior to commencement of the activity. Navy personnel 
must provide NMFS with advance notification and include information 
about the event in its annual activity reports to NMFS.
    (ii) Olympic Coast National Marine Sanctuary Mitigation Area (year-
round).
    (A) Surface ship hull-mounted MF1 mid-frequency active sonar during 
training. The Navy must not conduct more than 32 hours of surface ship 
hull-mounted MF1 mid-frequency active sonar during training annually.
    (B) Non-explosive bombing training. The Navy must not conduct non-
explosive bombing training activities.
    (C) Surface ship hull-mounted MF1 mid-frequency active sonar during 
testing. The Navy must not conduct more than a total of 33 hours of 
surface ship hull-mounted MF1 mid-frequency active sonar during testing 
annually within 20 nmi from shore in the Marine Species Coastal 
Mitigation Area, in the Juan de Fuca Eddy Marine Species Mitigation 
Area, and in the Olympic Coast National Marine Sanctuary Mitigation 
Area combined.
    (D) Explosive Mine Countermeasure and Neutralization testing. The 
Navy must not conduct explosive Mine Countermeasure and Neutralization 
Testing activities.
    (E) National security exception. Should national security require 
that the Navy cannot comply with the restrictions in paragraphs 
(a)(2)(ii)(A), (B), (C), or (D) of this section, Navy personnel must 
obtain permission from the appropriate designated Command authority 
prior to commencement of the activity. Navy personnel must provide NMFS 
with advance notification and include information about the event in 
its annual activity reports to NMFS.
    (iii) Juan de Fuca Eddy Marine Species Mitigation Area (year-
round).
    (A) Surface ship hull-mounted MF1 mid-frequency active sonar during 
testing. The Navy must not conduct more than a total of 33 hours of 
surface ship hull-mounted MF1 mid-frequency active sonar during testing 
annually within 20 nmi from shore in the Marine Species Coastal 
Mitigation Area, in the Juan de Fuca Eddy Marine Species Mitigation 
Area, and in the Olympic Coast National Marine Sanctuary Mitigation 
Area combined.
    (B) Explosive Mine Countermeasure and Neutralization testing. The 
Navy must not conduct explosive Mine Countermeasure and Neutralization 
Testing activities.
    (C) National security exception. Should national security require 
that the Navy cannot comply with the restrictions in paragraphs 
(a)(2)(iii)(A) or (B) of this section, Navy personnel must obtain 
permission from the appropriate designated Command authority prior to 
commencement of the activity. Navy personnel must provide NMFS with 
advance notification and include information about the event in its 
annual activity reports to NMFS.
    (iv) Stonewall and Heceta Bank Humpback Whale Mitigation Area (May 
1-November 30).
    (A) Surface ship hull-mounted MF1 mid-frequency active sonar. The 
Navy must not use surface ship hull-mounted MF1 mid-frequency active 
sonar during training and testing from May 1 to November 30.
    (B) Explosive Mine Countermeasure and Neutralization testing. The 
Navy must not conduct explosive Mine Countermeasure and Neutralization 
testing from May 1 to November 30.
    (C) National security exception. Should national security require 
that the Navy cannot comply with the restrictions in paragraphs 
(a)(2)(iv)(A) or (B) of this section, Navy personnel must obtain 
permission from the appropriate designated Command authority prior to 
commencement of the activity. Navy personnel must provide NMFS with 
advance notification and include

[[Page 72467]]

information about the event in its annual activity reports to NMFS.
    (v) Point St. George Humpback Whale Mitigation Area (July 1-
November 30).
    (A) Surface ship hull-mounted MF1 mid-frequency active sonar. The 
Navy must not use surface ship hull-mounted MF1 mid-frequency active 
sonar during training or testing from July 1 to November 30.
    (B) Explosive Mine Countermeasure and Neutralization testing. The 
Navy must not conduct explosive Mine Countermeasure and Neutralization 
Testing from July 1 to November 30.
    (C) National security exception. Should national security require 
that the Navy cannot comply with the restrictions in paragraphs 
(a)(2)(v)(A) or (B) of this section, Navy personnel must obtain 
permission from the appropriate designated Command authority prior to 
commencement of the activity. Navy personnel must provide NMFS with 
advance notification and include information about the event in its 
annual activity reports to NMFS.
    (vi) Northern Puget Sound Gray Whale Mitigation Area (March 1-May 
31).
    (A) Civilian port defense--homeland security anti-terrorism/force 
protection exercises. The Navy must not conduct Civilian Port Defense-
Homeland Security Anti-Terrorism/Force Protection Exercises from March 
1 to May 31.
    (B) National security exception. Should national security require 
that the Navy cannot comply with the restrictions in paragraph 
(a)(2)(vi)(A) of this section, Navy personnel must obtain permission 
from the appropriate designated Command authority prior to commencement 
of the activity. Navy personnel must provide NMFS with advance 
notification and include information about the event in its annual 
activity reports to NMFS.
    (vii) Puget Sound and Strait of Juan de Fuca Mitigation Area (year-
round unless specified as seasonal).
    (A) Active sonar use. The Navy must not use low-frequency, mid-
frequency, or high-frequency active sonar during training or testing 
within the Puget Sound and Strait of Juan de Fuca Mitigation Area, 
unless a required element (i.e., a criterion necessary for the success 
of the event) necessitates that the activity be conducted in NWTT 
Inland Waters during:
    (1) Unmanned underwater vehicle training.
    (2) Civilian port defense--homeland security anti-terrorism/force 
protection exercises.
    (3) Activities conducted by Naval Sea Systems Command at designated 
locations.
    (4) Pierside sonar maintenance or testing at designated locations.
    (B) Active sonar source levels. The Navy must use the lowest active 
sonar source levels practical to successfully accomplish each event. 
Naval units must obtain permission from the appropriate designated 
Command authority prior to commencing pierside maintenance or testing 
with hull-mounted mid-frequency active sonar.
    (C) Unmanned underwater vehicle training. The Navy must not conduct 
more than one Unmanned Underwater Vehicle Training activity annually at 
the Navy 3 OPAREA, Navy 7 OPAREA, and Manchester Fuel Depot (i.e., a 
maximum of one event at each location).
    (D) Use of explosives--(1) Explosives during testing. The Navy must 
not use explosives during testing.
    (2) Explosives during training. The Navy must not use explosives 
during training except at the Hood Canal EOD Range and Crescent Harbor 
EOD Range during explosive mine neutralization activities involving the 
use of Navy divers.
    (3) Explosives in bin E4 or above. The Navy must not use explosives 
in bin E4 (>2.5-5 lb. net explosive weight) or above, and must instead 
use explosives in bin E0 (< 0.1 lb. net explosive weight) or bin E3 
(>0.5-2.5 lb. net explosive weight).
    (4) Explosives in bin E3 during February, March, and April at the 
Hood Canal EOD Range. During February, March, and April at the Hood 
Canal EOD Range, the Navy must not use explosives in bin E3 (>0.5-2.5 
lb. net explosive weight), and must instead use explosives in bin E0 (< 
0.1 lb. net explosive weight).
    (5) Explosives in bin E3 during August, September, and October at 
the Hood Canal EOD Range. During August, September, and October at the 
Hood Canal EOD Range, the Navy must not use explosives in bin E3 (>0.5-
2.5 lb. net explosive weight) and must instead use explosives in bin E0 
(< 0.1 lb. net explosive weight) to the maximum extent practical unless 
necessitated by mission requirements.
    (6) Explosives at the Crescent Harbor EOD Range. At the Crescent 
Harbor EOD Range, the Navy must conduct explosive activities at least 
1,000 m from the closest point of land.
    (E) Non-explosive live fire events. The Navy must not conduct non-
explosive live fire events in the mitigation area (except firing blank 
weapons), including gunnery exercises, missile exercises, torpedo 
exercises, bombing exercises, and Kinetic Energy Weapon Testing.
    (F) Coordination with Navy biologists. Navy event planners must 
coordinate with Navy biologists during the event planning process prior 
to conducting the activities listed in paragraphs (a)(2)(vii)(F)(1), 
(2), (3), and (4) of this section. Navy biologists must work with NMFS 
and must initiate communication with the appropriate marine mammal 
detection networks to determine the likelihood of applicable marine 
mammal species presence in the planned training location. Navy 
biologists must notify event planners of the likelihood of species 
presence. To the maximum extent practical, Navy planners must use this 
information when planning specific details of the event (e.g., timing, 
location, duration) to avoid planning activities in locations or 
seasons where species presence is expected. The Navy must ensure 
environmental awareness of event participants. Environmental awareness 
will help alert participating crews to the possible presence of 
applicable species in the training location. Lookouts must use the 
information to assist visual observation of applicable mitigation zones 
and to aid in the implementation of procedural mitigation. Unmanned 
Underwater Vehicle Training events at the Navy 3 OPAREA, Manchester 
Fuel Depot, Crescent Harbor Explosive Ordnance Disposal Range, and Navy 
7 OPAREA must be cancelled or moved to another training location if the 
presence of Southern Resident killer whales is reported through 
available monitoring networks during the event planning process, or 
immediately prior to the event, as applicable.
    (1) Unmanned underwater vehicle training. Unmanned Underwater 
Vehicle Training at the Navy 3 OPAREA, Manchester Fuel Depot, Crescent 
Harbor Explosive Ordnance Disposal Range, and Navy 7 OPAREA (for 
Southern Resident killer whales);
    (2) Civilian port defense--homeland security anti-terrorism/force 
protection exercises. Civilian Port Defense--Homeland Security Anti-
Terrorism/Force Protection Exercises (for Southern Resident killer 
whales and gray whales);
    (3) Explosive mine neutralization activities involving the use of 
Navy divers. Explosive mine neutralization activities involving the use 
of Navy divers (for Southern Resident killer whales); and
    (4) Small boat attack exercises. Small Boat Attack Exercises, which 
involve firing blank small-caliber weapons (for Southern Resident 
killer whales and gray whales).

[[Page 72468]]

    (G) Seasonal awareness notification messages. The Navy must issue 
annual seasonal awareness notification messages to alert Navy ships and 
aircraft operating within the Puget Sound and Strait of Juan de Fuca 
Mitigation Area to the possible presence of concentrations of Southern 
Resident killer whales from July 1 to November 30 in Puget Sound and 
the Strait of Juan de Fuca, and concentrations of gray whales from 
March 1 to May 31 in the Strait of Juan de Fuca and northern Puget 
Sound. For safe navigation and to avoid interactions with large whales, 
the Navy must instruct vessels to remain vigilant to the presence of 
Southern Resident killer whales and gray whales that may be vulnerable 
to vessel strikes or potential impacts from training and testing 
activities. Platforms must use the information from the awareness 
notification messages to assist their visual observation of applicable 
mitigation zones during training and testing activities and to aid in 
the implementation of procedural mitigation.
    (H) National security exception. Should national security require 
that the Navy cannot comply with the restrictions in paragraphs 
(a)(2)(vii)(A), (B), (C), (D), or (E) of this section, Navy personnel 
must obtain permission from the appropriate designated Command 
authority prior to commencement of the activity. Navy personnel must 
provide NMFS with advance notification and include information about 
the event in its annual activity reports to NMFS.
    (3) Availability for Subsistence Use. The Navy must notify the 
following Alaskan Native communities of the issuance of Notices to 
Mariners of Navy operations that involve restricting access in the 
Western Behm Canal at least 72 hours in advance: Central Council of the 
Tlingit and Haida Indian Tribes, Ketchikan Indian Corporation, 
Organized Village of Saxman, and Metlakatla Indian Community, Annette 
Island Reserve.
    (b) [Reserved]


Sec.  218.145  Requirements for monitoring and reporting.

    (a) Notification of take. Navy personnel must notify NMFS 
immediately (or as soon as operational security considerations allow) 
if the specified activity identified in Sec.  218.140 is thought to 
have resulted in the mortality or serious injury of any marine mammals, 
or in any Level A harassment or Level B harassment of marine mammals 
not identified in this subpart.
    (b) Monitoring and reporting under the LOAs. The Navy must conduct 
all monitoring and reporting required under the LOAs, including abiding 
by the U.S. Navy's Marine Species Monitoring Program. Details on 
program goals, objectives, project selection process, and current 
projects are available at www.navymarinespeciesmonitoring.us.
    (c) Notification of injured, live stranded, or dead marine mammals. 
The Navy must consult the Notification and Reporting Plan, which sets 
out notification, reporting, and other requirements when dead, injured, 
or live stranded marine mammals are detected. The Notification and 
Reporting Plan is available at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.
    (d) Annual NWTT Study Area marine species monitoring report. The 
Navy must submit an annual report of the NWTT Study Area monitoring, 
which will be included in a Pacific-wide monitoring report including 
results specific to the NWTT Study Area, describing the implementation 
and results from the previous calendar year. Data collection methods 
must be standardized across Pacific Range Complexes including the 
Mariana Islands Training and Testing (MITT), Hawaii-Southern California 
Training and Testing (HSTT), NWTT, and Gulf of Alaska (GOA) Study Areas 
to allow for comparison in different geographic locations. The report 
must be submitted to the Director, Office of Protected Resources, NMFS, 
either within three months after the end of the calendar year, or 
within three months after the conclusion of the monitoring year, to be 
determined by the adaptive management process. NMFS will submit 
comments or questions on the report, if any, within three months of 
receipt. The report will be considered final after the Navy has 
addressed NMFS' comments, or three months after submittal of the draft 
if NMFS does not provide comments on the draft report. This report will 
describe progress of knowledge made with respect to intermediate 
scientific objectives within the NWTT Study Area associated with the 
Integrated Comprehensive Monitoring Program (ICMP). Similar study 
questions must be treated together so that progress on each topic can 
be summarized across all Navy ranges. The report need not include 
analyses and content that does not provide direct assessment of 
cumulative progress on the monitoring plan study questions. This will 
continue to allow the Navy to provide a cohesive monitoring report 
covering multiple ranges (as per ICMP goals), rather than entirely 
separate reports for the NWTT, HSTT, GOA, and MITT Study Areas.
    (e) NWTT Annual Training Exercise Report and Annual Testing 
Activity Report. Each year, the Navy must submit two preliminary 
reports (Quick Look Reports) detailing the status of applicable sound 
sources within 21 days after the anniversary of the date of issuance of 
each LOA to the Director, Office of Protected Resources, NMFS. The Navy 
must also submit detailed reports (NWTT Annual Training Exercise Report 
and Annual Testing Activity Report) to the Director, Office of 
Protected Resources, NMFS, within three months after the one-year 
anniversary of the date of issuance of the LOAs. NMFS will submit 
comments or questions on the reports, if any, within one month of 
receipt. The reports will be considered final after the Navy has 
addressed NMFS' comments, or one month after submittal of the draft if 
NMFS does not provide comments on the draft reports. The NWTT Annual 
Training Exercise Report and Annual Testing Activity Report can be 
consolidated with other exercise and activity reports from other range 
complexes in the Pacific Ocean for a single Pacific Training Exercise 
and Testing Activity Report, if desired. The annual reports must 
contain a summary of all sound sources used (total hours or quantity of 
each bin of sonar or other non-impulsive source; total annual number of 
each type of explosive; and total annual expended/detonated rounds 
(missiles, bombs, sonobuoys, etc.) for each explosive bin). The annual 
reports will also contain both the current year's sonar and explosive 
use data as well as cumulative sonar and explosive use quantity from 
previous years' reports. Additionally, if there were any changes to the 
sound source allowance in a given year, or cumulatively, the report 
must include a discussion of why the change was made and include 
analysis to support how the change did or did not affect the analysis 
in the 2020 NWTT FSEIS/OEIS and MMPA final rule. The annual report must 
also include details regarding specific requirements associated with 
the mitigation areas listed in Sec.  218.144(a)(2). The final annual/
close-out report at the conclusion of the authorization period (year 
seven) will serve as the comprehensive close-out report and include 
both the final year annual incidental take compared to annual 
authorized incidental take as well as cumulative seven-year incidental 
take compared to seven-year authorized incidental take. The Annual 
Training Exercise Report and Annual

[[Page 72469]]

Testing Activity Report must include the following information.
    (1) Summary of sources used. This section of the report must 
include the following information summarized from the authorized sound 
sources used in all training and testing events:
    (i) Sonar and other transducers. Total annual hours or quantity 
(per the LOA) of each bin of sonar or other transducers, and
    (ii) Explosives. Total annual expended/detonated ordinance 
(missiles, bombs, sonobuoys, etc.) for each explosive bin.
    (2) [Reserved]
    (f) Annual classified reports. Within the annual classified 
training exercise and testing activity reports, separate from the 
unclassified reports described in paragraphs (a) through (e) of this 
section, the Navy must specifically include the information described 
in paragraphs (f)(1) and (2) of this section.
    (1) Olympic Coast National Marine Sanctuary Mitigation Area. Total 
hours of authorized low-frequency, mid-frequency, and high-frequency 
active sonar (all bins, by bin) used during training and testing 
annually within the Olympic Coast National Marine Sanctuary Mitigation 
Area; and
    (2) Surface ship hull-mounted MF1 mid-frequency active sonar. Total 
hours of surface ship hull-mounted MF1 mid-frequency active sonar used 
in the following mitigation areas:
    (i) Testing annually in three combined areas. Testing annually 
within 20 nmi from shore in the Marine Species Coastal Mitigation Area, 
the Juan de Fuca Eddy Marine Species Mitigation Area, and the Olympic 
Coast National Marine Sanctuary Mitigation Area combined;
    (ii) Stonewall and Heceta Bank Humpback Whale Mitigation Area. 
Training and testing from May 1 to November 30 within the Stonewall and 
Heceta Bank Humpback Whale Mitigation Area; and
    (iii) Point St. George Humpback Whale Mitigation Area. Training and 
testing from July 1 to November 30 within the Point St. George Humpback 
Whale Mitigation Area.
    (g) Final close-out report. The final (year seven) draft annual/
close-out report must be submitted within three months after the 
expiration of this subpart to the Director, Office of Protected 
Resources, NMFS. NMFS will submit comments on the draft close-out 
report, if any, within three months of receipt. The report will be 
considered final after the Navy has addressed NMFS' comments, or three 
months after submittal of the draft if NMFS does not provide comments.


Sec.  218.146  Letters of Authorization.

    (a) To incidentally take marine mammals pursuant to the regulations 
in this subpart, the Navy must apply for and obtain LOAs in accordance 
with Sec.  216.106 of this chapter.
    (b) An LOA, unless suspended or revoked, may be effective for a 
period of time not to exceed the expiration date of this subpart.
    (c) If an LOA expires prior to the expiration date of this subpart, 
the Navy may apply for and obtain a renewal of the LOA.
    (d) In the event of projected changes to the activity or to 
mitigation, monitoring, or reporting (excluding changes made pursuant 
to the adaptive management provision of Sec.  218.147(c)(1)) required 
by an LOA issued under this subpart, the Navy must apply for and obtain 
a modification of the LOA as described in Sec.  218.147.
    (e) Each LOA will set forth:
    (1) Permissible methods of incidental taking;
    (2) Geographic areas for incidental taking;
    (3) Means of effecting the least practicable adverse impact (i.e., 
mitigation) on the species and stocks of marine mammals and their 
habitat; and
    (4) Requirements for monitoring and reporting.
    (f) Issuance of the LOA(s) must be based on a determination that 
the level of taking is consistent with the findings made for the total 
taking allowable under the regulations in this subpart.
    (g) Notice of issuance or denial of the LOA(s) will be published in 
the Federal Register within 30 days of a determination.


Sec.  218.147  Renewals and modifications of Letters of Authorization.

    (a) An LOA issued under Sec. Sec.  216.106 of this chapter and 
218.146 for the activity identified in Sec.  218.140(c) may be renewed 
or modified upon request by the applicant, provided that:
    (1) The planned specified activity and mitigation, monitoring, and 
reporting measures, as well as the anticipated impacts, are the same as 
those described and analyzed for the regulations in this subpart 
(excluding changes made pursuant to the adaptive management provision 
in paragraph (c)(1) of this section); and
    (2) NMFS determines that the mitigation, monitoring, and reporting 
measures required by the previous LOAs were implemented.
    (b) For LOA modification or renewal requests by the applicant that 
include changes to the activity or to the mitigation, monitoring, or 
reporting measures (excluding changes made pursuant to the adaptive 
management provision in paragraph (c)(1) of this section) that do not 
change the findings made for the regulations or result in no more than 
a minor change in the total estimated number of takes (or distribution 
by species or stock or years), NMFS may publish a notice of planned LOA 
in the Federal Register, including the associated analysis of the 
change, and solicit public comment before issuing the LOA.
    (c) An LOA issued under Sec. Sec.  216.106 of this chapter and 
218.146 may be modified by NMFS under the following circumstances:
    (1) After consulting with the Navy regarding the practicability of 
the modifications, NMFS may modify (including adding or removing 
measures) the existing mitigation, monitoring, or reporting measures if 
doing so creates a reasonable likelihood of more effectively 
accomplishing the goals of the mitigation and monitoring, as part of an 
adaptive management process.
    (i) Possible sources of data that could contribute to the decision 
to modify the mitigation, monitoring, or reporting measures in an LOA 
include:
    (A) Results from the Navy's monitoring report and annual exercise 
reports from the previous year(s);
    (B) Results from other marine mammal and/or sound research or 
studies; or
    (C) Any information that reveals marine mammals may have been taken 
in a manner, extent, or number not authorized by this subpart or 
subsequent LOAs.
    (ii) If, through adaptive management, the modifications to the 
mitigation, monitoring, or reporting measures are substantial, NMFS 
will publish a notice of planned LOA in the Federal Register and 
solicit public comment.
    (2) If NMFS determines that an emergency exists that poses a 
significant risk to the well-being of the species or stocks of marine 
mammals specified in LOAs issued pursuant to Sec. Sec.  216.106 of this 
chapter and 218.146, an LOA may be modified without prior notice or 
opportunity for public comment. Notice would be published in the 
Federal Register within 30 days of the action.


Sec.  218.148  [Reserved]

[FR Doc. 2020-23757 Filed 11-5-20; 8:45 am]
BILLING CODE 3510-22-P