[Federal Register Volume 83, Number 247 (Thursday, December 27, 2018)]
[Rules and Regulations]
[Pages 66846-67031]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-27342]
[[Page 66845]]
Vol. 83
Thursday,
No. 247
December 27, 2018
Part II
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 Hawaii-Southern
California Training and Testing Study Area; Final Rule
Federal Register / Vol. 83 , No. 247 / Thursday, December 27, 2018 /
Rules and Regulations
[[Page 66846]]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
50 CFR Part 218
[Docket No. 170918908-8999-02]
RIN 0648-BH29
Taking and Importing Marine Mammals; Taking Marine Mammals
Incidental to the U.S. Navy Training and Testing Activities in the
Hawaii-Southern California Training and Testing 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 Hawaii-Southern California Training
and Testing (HSTT) Study Area over the course of five years beginning
in December 2018. 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 or stocks and their
habitat, and establish requirements pertaining to the monitoring and
reporting of such taking.
DATES: Effective from December 21, 2018 through December 20, 2023.
ADDRESSES: A copy of the Navy's application and supporting documents,
as well as a list of the references cited in this document, 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 call
the contact listed below (see FOR FURTHER INFORMATION CONTACT).
FOR FURTHER INFORMATION CONTACT: Stephanie Egger, Office of Protected
Resources, National Marine Fisheries Service, 1315 East-West Highway,
Silver Spring, MD 20910, (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.), establish a framework for authorizing the take of
marine mammals incidental to the Navy's training and testing activities
(categorized as military readiness activities) from the use of sonar
and other transducers, in-water detonations, air guns, impact pile
driving/vibratory extraction, and potential vessel strikes based on
Navy movement throughout the HSTT Study Area. The HSTT Study Area (see
Figure 1.1-1 of the Navy's rulemaking/LOA application) is comprised of
established operating and warning areas across the north-central
Pacific Ocean, from the mean high tide line in Southern California west
to Hawaii and the International Date Line. The Study Area includes the
at-sea areas of three existing range complexes (the Hawaii Range
Complex, the Southern California (SOCAL) Range Complex, and the Silver
Strand Training Complex), and overlaps a portion of the Point Mugu Sea
Range (PMSR). Also included in the Study Area are Navy pierside
locations in Hawaii and Southern California, Pearl Harbor, San Diego
Bay, and the transit corridor \1\ on the high seas where sonar training
and testing may occur.
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\1\ Vessel transit corridors are the routes typically used by
Navy assets to traverse from one area to another. The route depicted
in Figure 1-1 of the Navy's rulemaking/LOA application is the
shortest route between Hawaii and Southern California, making it the
quickest and most fuel efficient. The depicted vessel transit
corridor is notional and may not represent the actual routes used by
ships and submarines transiting from Southern California to Hawaii
and back. Actual routes navigated are based on a number of factors
including, but not limited to, weather, training, and operational
requirements.
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We received an application from the Navy requesting five-year
regulations and authorizations to incidentally take individuals of
multiple species and stocks of marine mammals (``Navy's rulemaking/LOA
application'' or ``Navy's application''). Take is anticipated to occur
by Level A 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
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:
[ssquf] The use of defined powerdown and shutdown zones (based
on activity);
[ssquf] Measures to reduce or eliminate the likelihood of ship
strikes;
[ssquf] Activity limitations in certain areas and times that are
biologically important (i.e., for foraging, migration, reproduction)
for marine mammals;
[ssquf] Implementation of a Notification and Reporting Plan (for
dead, live stranded, or marine mammals struck by a vessel); and
[ssquf] 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
Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.)
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 a 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
stock(s), will not have an unmitigable adverse impact on the
availability of the species or stock(s) for subsistence uses (where
relevant), and if the permissible methods of taking, other means of
effecting the least practicable adverse impact on the species or stocks
and their habitat, and requirements pertaining to monitoring and
reporting of such takings are set forth. The MMPA states that the term
``take'' means to harass, hunt, capture, kill or attempt to harass,
hunt, capture, or kill any marine mammal.
[[Page 66847]]
The National Defense Authorization Act of 2004 (2004 NDAA) (Pub. L.
108-136) amended section 101(a)(5) of the MMPA to remove the ``small
numbers'' and ``specified geographical region'' provisions indicated
above for ``military readiness activities'' and amended the definition
of ``harassment'' as it applies to military readiness activities, along
with certain research activities. The definitions of all applicable
MMPA statutory terms cited above are included in the relevant sections
below.
More recently, the John S. McCain National Defense Authorization
Act for Fiscal Year 2019 (2019 NDAA) (Pub. L. 115-232) amended the MMPA
to allow incidental take rules for military readiness activities to be
issued for up to seven years. That recent amendment of the MMPA does
not affect this final rule, however, because both the Navy's
application and NMFS' proposed incidental take rule preceded passage of
the 2019 NDAA and contemplated authorization for five years.
Summary and Background of Request
On September 13, 2017, NMFS received an application from the Navy
for authorization to take marine mammals by Level A and B harassment
incidental to training and testing activities (categorized as military
readiness activities) from the use of sonar and other transducers, in-
water detonations, air guns, and impact pile driving/vibratory
extraction in the HSTT Study Area. In addition, the Navy requested
incidental take authorization by serious injury or mortality for a
combined ten takes of two marine mammal species from explosives and for
up to three takes of large whales from vessel strikes over the five-
year period. On October 13, 2017, the Navy sent an amendment to its
application and the application was found to be adequate and complete.
On October 20, 2017 (82 FR 48801), we published a notice of receipt of
application (NOR) in the Federal Register, requesting comments and
information related to the Navy's request for 30 days. On June 26,
2018, we published a notice of the proposed rulemaking (83 FR 29872)
and requested comments and information related to the Navy's request
for 45 days. Comments received during the NOR and the proposed
rulemaking comment periods are addressed in this final rule. See
further details addressing comments received in the Comments and
Responses section.
On September 10, 2018, and October 26, 2018, Navy provided NMFS
with memoranda revising the estimated takes by serious injury or
mortality included in the Navy's rulemaking/LOA application for ship
strike. The Navy's request for takes by serious injury or mortality of
three large whales over the course of five years remains unchanged.
However, specifically, after further analysis and discussion with NMFS,
the Navy modified their request for takes from particular stocks in the
following ways:
Humpback whales (California, Oregon, Washington (CA/OR/
WA) stock):
[cir] Reduced request for take from two to one individual.
[cir] Removed the authorization request for individuals that
also are part of the Central America Distinct Population Segment
(DPS) recognized under the Endangered Species Act (ESA). Both the
Central America DPS and Mexico DPS overlap with the CA/OR/WA stock,
but from this stock, only a humpback whale from the Mexico DPS is
expected to be taken by serious injury or mortality. These
individuals, that are part of both the CA/OR/WA stock and the Mexico
DPS, will be referred to as ``humpback whales (CA/OR/WA stock,
Mexico DPS)'' henceforth.
Sperm whale (Hawaii or CA/OR/WA stock):
[cir] Original authorization request for take was for two total
from any stock; reduced request for take to one individual.
[cir] Removed request for individuals from the CA/OR/WA stock,
i.e., only an individual from the Hawaii stock is requested.
Bryde's whale (Eastern Tropical Pacific stock or Hawaii
stock)--Reduced request for take from one individual to zero.
Minke whale (Hawaii stock)--Reduced request for take
from one individual to zero.
Sei whale (Hawaii stock and Eastern North Pacific
stock)--Reduced request for take from one individual to zero.
NMFS concurs that it is reasonably likely that these lethal takes
could occur. The information and assessment that supports this change
is included in the Estimated Take of Marine Mammals section.
The Navy requested two five-year LOAs, one for training activities
and one for testing activities to be conducted within the HSTT Study
Area. The HSTT Study Area (see Figure 1.1-1 of the Navy's rulemaking/
LOA application) is comprised of established operating and warning
areas across the north-central Pacific Ocean, from the mean high tide
line in Southern California west to Hawaii and the International Date
Line. The Study Area includes the at-sea areas of three existing range
complexes (the Hawaii Range Complex, the SOCAL Range Complex, and the
Silver Strand Training Complex), and overlaps a portion of the PMSR.
Also included in the Study Area are Navy pierside locations in Hawaii
and Southern California, Pearl Harbor, San Diego Bay, and the transit
corridor on the high seas where sonar training and testing may occur.
The following types of training and testing, which are classified
as military readiness activities pursuant to the MMPA, as amended by
the 2004 NDAA, would be covered under the regulations and associated
LOAs: Amphibious warfare (in-water detonations), anti-submarine warfare
(sonar and other transducers, in-water detonations), surface warfare
(in-water detonations), mine warfare (sonar and other transducers, in-
water detonations), and other warfare activities (sonar and other
transducers, pile driving, air guns). Also, ship strike by Navy vessels
is addressed and covered, as appropriate.
This will be NMFS' third in a series of rulemakings for testing and
training activities in the HSTT Study Area. Hawaii and Southern
California were separate in the initial rulemaking period, and the
first two rules were effective from January 5, 2009, through January 5,
2014 (74 FR 1456; January 12, 2009), and January 14, 2009, through
January 14, 2014 (74 FR 3882; January 21, 2009), respectively. The
rulemaking for the second five-year period, which combined Hawaii and
Southern California, was in effect from December 24, 2013, through
December 24, 2018 (78 FR 78106; December 24, 2013), as modified by the
terms of a stipulated settlement agreement and order issued by the
United States District Court for the District of Hawaii on September
14, 2015. The new regulations described here will be valid for five
years, from December 21, 2018, though December 20, 2023.
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. 5062), which ensures the readiness
of the naval forces of the United States. The Navy executes this
responsibility 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
activities.
The Navy plans to conduct training and testing activities within
the HSTT Study Area. The Navy has been conducting similar military
readiness activities in the HSTT Study Area since the 1940s. The tempo
and types of training and testing activities have fluctuated because of
the introduction of new technologies, the evolving nature of
international events, advances in warfighting doctrine and procedures,
and changes in force structure
[[Page 66848]]
(organization of ships, weapons, and personnel). Such developments
influenced the frequency, duration, intensity, and location of required
training and testing activities, but the basic nature of sonar and
explosive events conducted in the HSTT Study Area has remained the
same.
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 would
occur for a five-year period following the expiration of the current
MMPA authorization for the HSTT Study Area, which expires on December
24, 2018.
Description of the Specified Activity
Additional detail regarding the specified activity was provided in
our Federal Register notice of proposed rulemaking (83 FR 29872; June
26, 2018); please see that notice of proposed rulemaking or the Navy's
application for more information. Since the proposed rule, NMFS and the
Navy have reached agreement on additional mitigation measures which are
summarized below and discussed in greater detail in the Mitigation
Measures section of this rule.
The Navy will implement pre- and post-event observation of the
mitigation zone for all in-water explosive event mitigation measures in
the HSTT Study Area. The Navy expanded their mitigation areas to
include the sections of the Santa Monica Bay to Long Beach and San
Nicolas Island biologically important areas (BIAs) that overlap the
HSTT Study Area. These areas are referred to as the Santa Monica/Long
Beach and San Nicolas Island Mitigation Areas and explosive use is
limited in these areas as described in the Mitigation Measures section.
Further, the Navy will limit surface ship sonar such that it will not
exceed 200 hours from June through October cumulatively within the San
Diego Arc, San Nicolas Island, and Santa Monica/Long Beach, Mitigation
Areas. The Navy will also add a year-round limitation on explosives to
the 4-Islands Region Mitigation Area, which includes a portion of the
false killer whale (Main Hawaiian Island insular stock) BIA north of
Maui and Molokai in the HSTT Study Area. The Navy has agreed to issue
notification messages to increase operator awareness of the presence of
marine mammals. The Navy will review WhaleWatch, a program coordinated
by NMFS' West Coast Region as an additional information source to
inform the drafting of the seasonal awareness message to alert vessels
in the area to the possible presence of concentrations of large whales,
including blue, gray, and fin whales in SOCAL.
In coordination with NMFS, the Navy has also revised its estimate
of and request for serious injury or mortality takes of large whales
from ship strikes, as described immediately above in the Summary and
Background of Request section. The detailed rationale for this change
is provided in the Estimated Take of Marine Mammals section.
Overview of Training and Testing Activities
The Navy routinely trains and tests in the HSTT Study Area in
preparation for national defense missions. Training and testing
activities covered in these regulations are summarized below.
Primary Mission Areas
The Navy categorizes its activities into functional warfare areas
called primary mission areas. These activities generally fall into the
following seven primary mission areas: Air warfare; amphibious warfare;
anti-submarine warfare (ASW); electronic warfare; expeditionary
warfare; mine warfare (MIW); and surface warfare (SUW). Most activities
addressed in the HSTT FEIS/OEIS are categorized under one of the
primary mission areas; the testing community has three additional
categories of activities for vessel evaluation, unmanned systems, and
acoustic and oceanographic science and technology. Activities that do
not fall within one of these areas are listed as ``other activities.''
Each warfare community (surface, subsurface, aviation, and special
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.
The Navy describes and analyzes the impacts of its training and
testing activities within the HSTT FEIS/OEIS and the Navy's rulemaking/
LOA application (documents available at www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities). In its assessment, the Navy concluded
that sonar and other transducers, in-water detonations, air guns, and
pile driving/removal were the stressors that would result in impacts on
marine mammals that could rise to the level of harassment (and serious
injury or mortality by explosives or by vessel strike) as defined under
the MMPA. Therefore, the 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. In
terms of Navy's primary warfare areas, this includes:
[ssquf] Amphibious warfare (in-water detonations);
[ssquf] ASW (sonar and other transducers, in-water detonations);
[ssquf] SUW (in-water detonations);
[ssquf] MIW (sonar and other transducers, in-water detonations);
and
[ssquf] Other warfare activities (sonar and other transducers,
impact pile driving/vibratory removal, air guns).
Overview of Major Training Exercises and Other Exercises Within the
HSTT Study Area
A major training exercise (MTE) is comprised of several ``unit
level'' range exercises conducted by several units operating together
while commanded and controlled by a single Commander. These exercises
typically employ an exercise scenario developed to train and evaluate
the strike group in naval tactical tasks. In an MTE, most of the
activities being directed and coordinated by the Commander are
identical in nature to the activities conducted during individual,
crew, and smaller unit level training events. In an MTE, however, these
disparate training tasks are conducted in concert, rather than in
isolation.
Some integrated or coordinated ASW exercises are similar in that
they are comprised of several unit level exercises but are generally on
a smaller scale than an MTE, are shorter in duration, use fewer assets,
and use fewer hours of hull-mounted sonar per exercise. For the purpose
of analysis, three key factors are used to identify and group major,
integrated, and coordinated exercises including the scale of the
exercise, duration of the exercise, and amount of hull-mounted sonar
hours modeled/used for the exercise. NMFS considered the effects of all
training exercises, not just these major, integrated, and coordinated
training exercises in these regulations. Additional detail regarding
the training activities was provided in our Federal Register notice of
proposed rulemaking (83 FR 29872; June 26, 2018); please see that
notice of proposed rulemaking or the Navy's application for more
information.
Overview of Testing Activities Within the HSTT Study Area
The Navy's research and acquisition community engages in a broad
spectrum
[[Page 66849]]
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 (e.g., missiles, radar, and sonar) and platforms (e.g., surface
ships, submarines, and aircraft); and acquisition of systems and
platforms to support Navy missions and give a technological edge over
adversaries. The individual commands within the research and
acquisition community included in the Navy's rulemaking/LOA application
are the Naval Air Systems Command, the Naval Sea Systems Command, the
Office of Naval Research, and the Space and Naval Warfare Systems
Command. Additional detail regarding the testing activities was
provided in our Federal Register notice of proposed rulemaking (83 FR
29872; June 26, 2018); please see that notice of proposed rulemaking or
the Navy's application for more information.
Dates and Duration
The specified activities may occur at any time during the five-year
period of validity of the regulations. Planned number and duration of
training and testing activities are shown in the Planned Activities
section (Tables 4 through 7).
Specific Geographic Area
The Navy's HSTT Study Area extends from the north-central Pacific
Ocean, from the mean high tide line in Southern California west to
Hawaii and the International Date Line, including the Hawaii and
Southern California (SOCAL) Range Complexes, as well as the Silver
Strand Training Complex and overlapping a small portion of the Point
Mugu Sea Range (PMSR). Please refer to Figure 1-1 of the Navy's
rulemaking/LOA application for a map of the HSTT Study Area, Figures 2-
1 to 2-4 for the Hawaii Operating Area (where the majority of training
and testing activities occur within the Hawaii Range Complex), Figures
2-5 to 2-7 for the SOCAL Range Complex, and Figure 2-8 for the Silver
Strand Training Complex.
Description of Acoustic and Explosive 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 Navy's rulemaking/LOA application describes
specific components that could act as stressors by having direct or
indirect impacts on the environment. The following subsections describe
the acoustic and explosive stressors for biological resources within
the HSTT Study Area. Because of the complexity of analyzing sound
propagation in the ocean environment, the Navy relies on acoustic
models in its environmental analyses that consider sound source
characteristics and varying ocean conditions across the HSTT Study
Area. Stressor/resource interactions that were determined to have de
minimus or no impacts (i.e., vessel, aircraft, or weapons noise) were
not carried forward for analysis in the Navy's rulemaking/LOA
application. NMFS reviewed the Navy's analysis and conclusions and
finds them complete and supportable.
Acoustic Stressors
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, to sound waves),
and air guns, as well as incidental sources of broadband sound produced
as a byproduct of impact pile driving and vibratory extraction.
Explosives also produce broadband sound but are analyzed separately
from other acoustic sources due to their unique characteristics. 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 sonars, other transducers, air guns, 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 pile driving, vessel or aircraft transits, weapons
firing, and bow shocks.
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 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, safely navigate, 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.
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 sonar used to find and track
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 (>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 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 (83 FR 29872; June 26, 2018); 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. 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, as follows:
[ssquf] 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;
[ssquf] Sound pressure level (SPL) of the non-impulsive source;
[[Page 66850]]
[cir] Greater than 160 decibels (dB) re 1 micro Pascal ([mu]Pa),
but less than 180 dB re 1 [mu]Pa;
[cir] Equal to 180 dB re 1 [mu]Pa and up to 200 dB re 1 [mu]Pa;
[cir] Greater than 200 dB re 1 [mu]Pa;
[ssquf] 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 HSTT Study Area are shown in Table 1
below. While general parameters or source characteristics are shown in
the table, actual source parameters are classified.
Table 1--Sonar and Transducers Quantitatively Analyzed in the HSTT Study
Area
------------------------------------------------------------------------
Source class category Bin Description
------------------------------------------------------------------------
Low-Frequency (LF): Sources LF3 LF sources greater
that produce signals less than LF4 than 200 dB.
1 kHz. LF sources equal to
180 dB and up to 200
dB.
LF5 LF sources less than
180 dB.
LF6 LF sources greater
than 200 dB with long
pulse lengths.
Mid-Frequency (MF): Tactical MF1 Hull-mounted surface
and non-tactical sources that ship sonars (e.g., AN/
produce signals between 1-10 SQS-53C and AN/SQS-
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-13).
MF5 Active acoustic
sonobuoys (e.g.,
DICASS).
MF6 Active underwater
sound signal devices
(e.g., MK84).
MF8 Active sources
(greater than 200 dB)
not otherwise binned.
MF9 Active 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%.
MF12 Towed array surface
ship sonars with an
active duty cycle
greater than 80%.
MF13 MF sonar sources.
High-Frequency (HF): Tactical HF1 Hull-mounted submarine
and non-tactical sources that HF2 sonars (e.g., AN/BQQ-
produce signals between 10-100 10).
kHz. HF Marine Mammal
Monitoring System.
HF3 Other hull-mounted
submarine sonars
(classified).
HF4 Mine detection,
classification, and
neutralization sonar
(e.g., AQS-20).
HF5 Active sources
(greater than 200 dB)
not otherwise binned.
HF6 Active sources (equal
to 180 dB and up to
200 dB) not otherwise
binned.
HF7 Active sources
(greater than 160 dB,
but less than 180 dB)
not otherwise binned.
HF8 Hull-mounted surface
ship sonars (e.g., AN/
SQS-61).
Anti-Submarine Warfare (ASW): ASW1 MF systems operating
Tactical sources (e.g., active ASW2 above 200 dB.
sonobuoys and acoustic counter- ASW3 MF Multistatic Active
measures systems) used during Coherent sonobuoy
ASW training and testing (e.g., AN/SSQ-125).
activities. MF towed active
acoustic
countermeasure
systems (e.g., AN/SLQ-
25).
ASW4 MF expendable active
acoustic device
countermeasures
(e.g., MK 3).
ASW5 MF sonobuoys with high
duty cycles.
Torpedoes (TORP): Source TORP1 Lightweight torpedo
classes associated with the (e.g., MK 46, MK 54,
active acoustic signals or Anti-Torpedo
produced by torpedoes. Torpedo).
TORP2 Heavyweight torpedo
(e.g., MK 48).
TORP3 Heavyweight torpedo
(e.g., MK 48).
Forward Looking Sonar (FLS): FLS2 HF sources with short
Forward or upward looking pulse lengths, narrow
object avoidance sonars used beam widths, and
for ship navigation and safety. focused beam
patterns.
FLS3 VHF sources with short
pulse lengths, narrow
beam widths, and
focused beam
patterns.
Acoustic Modems (M): Systems M3 MF acoustic modems
used to transmit data through (greater than 190
the water. dB).
Swimmer Detection Sonars (SD): SD1-SD2 HF and VHF sources
Systems used to detect divers with short pulse
and submerged swimmers. lengths, used for the
detection of swimmers
and other objects for
the purpose of port
security.
Synthetic Aperture Sonars SAS1 MF SAS systems.
(SAS): Sonars in which active SAS2 HF SAS systems.
acoustic signals are post- SAS3 VHF SAS systems.
processed to form high-
resolution images of the
seafloor.
SAS4 MF to HF broadband
mine countermeasure
sonar.
Broadband Sound Sources (BB): BB4 LF to MF oceanographic
Sonar systems with large BB7 source.
frequency spectra, used for LF oceanographic
various purposes. source.
BB9 MF optoacoustic
source.
------------------------------------------------------------------------
Notes: ASW: Antisubmarine Warfare; BB: Broadband Sound Sources; FLS:
Forward Looking Sonar; HF: High-Frequency; LF: Low-Frequency; M:
Acoustic Modems; MF: Mid-Frequency; SAS: Synthetic Aperture Sonars;
SD: Swimmer Detection Sonars; TORP: Torpedoes; VHF: Very High-
Frequency.
[[Page 66851]]
Air Guns
Small air guns with capacities up to 60 cubic inches (in\3\) would
be used during testing activities in various offshore areas of the
Southern California Range Complex and in the Hawaii Range Complex.
Generated impulses would have short durations, typically a few hundred
milliseconds, with dominant frequencies below 1 kHz. The root mean
square (SPL rms) and peak pressure (SPL peak) at a distance 1 meter (m)
from the air gun would be approximately 215 dB re 1 [mu]Pa and 227 dB
re 1 [mu]Pa, respectively, if operated at the full capacity of 60
in\3\.
Pile Driving/Extraction
Impact pile driving and vibratory pile removal would occur during
construction of an Elevated Causeway System (ELCAS), a temporary pier
that allows the offloading of ships in areas without a permanent port.
The source levels of the noise produced by impact pile driving and
vibratory pile removal from an actual ELCAS impact pile driving and
vibratory removal are shown in Table 2.
Table 2--Elevated Causeway System Pile Driving and Removal Underwater Sound Levels in the HSTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Pile size and type Method Average sound levels at 10 m
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
24-in. Steel Pipe Pile................... Impact \1\................. 192 dB re 1 [micro]Pa SPL rms, 182 dB re 1 [micro]Pa\2\s SEL (single strike).
24-in. Steel Pipe Pile................... Vibratory \2\.............. 146 dB re 1 [micro]Pa SPL rms, 145 dB re 1 [micro]Pa\2\s SEL (per second of duration).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Illingworth and Rodkin (2016), \2\ Illingworth and Rodkin (2015).
Notes: in = inch, SEL = Sound Exposure Level, SPL = Sound Pressure Level, rms = root mean squared, dB re 1 [micro]Pa = decibels referenced to 1 micropascal.
The size of the pier and number of piles used in an ELCAS event is
approximately 1,520 ft long, requiring 119 supporting piles.
Construction of the ELCAS would involve intermittent impact pile
driving over approximately 20 days. Crews work 24 hours (hrs) a day and
would drive approximately 6 piles in that period. Each pile takes about
15 minutes to drive with time taken between piles to reposition the
driver. When training events that use the ELCAS are complete, the
structure would be removed using vibratory methods over approximately
10 days. Crews would remove about 12 piles per 24-hour period, each
taking about 6 minutes to remove.
Explosive Stressors
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
Appendix A (Navy Activity Descriptions) of the HSTT FEIS/OEIS.
Additional detail regarding explosive stressors was provided in our
Federal Register notice of proposed rulemaking (83 FR 29872; June 26,
2018); please see that notice of proposed rulemaking or the Navy's
application for more information.
Explosive detonations during training and testing activities are
associated with high-explosive munitions, including, but not limited
to, bombs, missiles, rockets, 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 at the water's surface. Explosive detonations associated
with torpedoes and explosive sonobuoys would occur in the water column;
mines and demolition charges would be detonated in the water column or
on the ocean bottom. Most detonations would occur in waters greater
than 200 ft in depth, and greater than 3 nautical miles (Nmi) from
shore, although most mine warfare, demolition, and some testing
detonations would occur in shallow water close to shore. Those that
occur close to shore are typically conducted on designated ranges.
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. Explosives detonated in water are binned by net
explosive weight. The bins of explosives that are for use in the HSTT
Study Area are shown in Table 3 below.
Table 3--Explosives Analyzed in the HSTT Study Area
------------------------------------------------------------------------
Net explosive Example explosive
Bin weight \1\ (lb) source
------------------------------------------------------------------------
E1.............................. 0.1-0.25.......... Medium-caliber
projectile.
E2.............................. >0.25-0.5......... Medium-caliber
projectile.
E3.............................. >0.5-2.5.......... Large-caliber
projectile.
E4.............................. >2.5-5............ Mine
neutralization
charge.
E5.............................. >5-10............. 5-inch projectile.
E6.............................. >10-20............ Hellfire missile.
E7.............................. >20-60............ Demo block/shaped
charge.
E8.............................. >60-100........... Light-weight
torpedo.
E9.............................. >100-250.......... 500 lb. bomb.
E10............................. >250-500.......... Harpoon missile.
E11............................. >500-650.......... 650 lb. mine.
E12............................. >650-1,000........ 2,000 lb. bomb.
E13 \2\......................... >1,000-1,740...... Multiple Mat Weave
charges.
------------------------------------------------------------------------
\1\ Net Explosive Weight refers to the equivalent amount of TNT.
\2\ E13 is not modeled for protected species impacts in water because
most energy is lost into the air or to the bottom substrate due to
detonation in very shallow water. In addition, activities are confined
to small coves without regular marine mammal occurrence. These are not
single charges, but multiple smaller charges detonated simultaneously
or within a short time period.
[[Page 66852]]
Explosive Fragments
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. In
contrast, 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 far exceed the zone where fragments could
injure or kill an animal, the thresholds 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 HSTT 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 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 movements is provided in the
Planned Activities section. Additional detail on vessel strike was
provided in our Federal Register notice of proposed rulemaking (83 FR
29872; June 26, 2018); please see that notice of proposed rulemaking or
the Navy's application for more information. Additionally, as
referenced above and described in more detail in the Estimated Take of
Marine Mammals section, on September 10, 2018, and October 26, 2018,
the Navy provided additional information withdrawing and reducing
certain species from their request for serious injury or mortality
takes from vessel strike with explanation supporting the Navy's change
in requested take.
Planned Activities
Planned Training Activities
The training activities that the Navy plans to conduct in the HSTT
Study Area are summarized in Table 4. The table is organized according
to primary mission areas and includes the activity name, associated
stressors applicable to these regulations, description of the activity,
sound source bin, the number of planned activities, and the locations
of those activities in the HSTT Study Area. For further information
regarding the primary platform used (e.g., ship or aircraft type) see
Appendix A (Navy Activity Descriptions) of the HSTT FEIS/OEIS.
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Planned Testing Activities
Testing activities covered in these regulations are described in
Table 5 through Table 8.
Naval Air Systems Command
Table 5 summarizes the planned testing activities for the Naval Air
Systems Command analyzed within the HSTT Study Area.
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Naval Sea Systems Command
Table 6 summarizes the planned testing activities for the Naval Sea
Systems Command analyzed within the HSTT Study Area.
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Office of Naval Research
Table 7 summarizes the planned testing activities for the Office of
Naval Research analyzed within the HSTT Study Area.
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Space and Naval Warfare Systems Command
Table 8 summarizes the planned testing activities for the Space and
Naval Warfare Systems Command analyzed within the HSTT Study Area.
[[Page 66866]]
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Summary of Acoustic and Explosive Sources Analyzed for Training and
Testing
Table 9 through Table 12 show the acoustic source classes and
numbers, explosive source bins and numbers, air gun sources, and pile
driving and removal activities associated with Navy training and
testing activities in the HSTT Study Area that were analyzed in this
rule. Table 9 shows the acoustic source classes (i.e., LF, MF, and HF)
that could occur in any year under the Planned Activities for training
and testing activities. Under the Planned Activities, acoustic source
class use would vary annually, consistent with the number of annual
activities summarized above. The five-year total for the Planned
Activities takes into account that annual variability.
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Table 10 shows the number of air gun shots planned in the HSTT
Study Area for training and testing activities.
Table 10--Training and Testing Air Gun Sources Quantitatively Analyzed in the HSTT Study Area
----------------------------------------------------------------------------------------------------------------
Training Testing
Source class category Bin Unit \1\ -------------------------------------------------------
Annual 5-Year total Annual 5-Year total
----------------------------------------------------------------------------------------------------------------
Air Guns (AG): Small AG C 0 0 844 4,220
underwater air guns........
----------------------------------------------------------------------------------------------------------------
\1\ C = count. One count (C) of AG is equivalent to 100 air gun firings.
Table 11 summarizes the impact pile driving and vibratory pile
removal activities that would occur during a 24-hour period. Annually,
for impact pile driving, the Navy will drive 119 piles, two times a
year for a total of 238 piles. Over the five-year period of the rule,
the Navy will drive a total of 1,190 piles by impact pile driving.
Annually, for vibratory pile extraction, the Navy will extract 119
piles, two times a year for a total of 238 piles. Over the five-year
period of the rule, the Navy will extract a total of 1,190 piles by
vibratory pile extraction.
Table 11--Summary of Pile Driving and Removal Activities per 24-Hour Period in the HSTT Study Area
----------------------------------------------------------------------------------------------------------------
Total
estimated time
Method Piles per 24- Time per pile of noise per
hour period minutes 24-hour period
minutes
----------------------------------------------------------------------------------------------------------------
Pile Driving (Impact)........................................... 6 15 90
Pile Removal (Vibratory)........................................ 12 6 72
----------------------------------------------------------------------------------------------------------------
[[Page 66871]]
Table 12 shows the number of in-water explosives that could be used
in any year under the Planned Activities for training and testing
activities. Under the Planned Activities, bin use would vary annually,
consistent with the number of annual activities summarized above. The
five-year total for the Planned Activities takes into account that
annual variability.
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Vessel Movement
Vessels used as part of the Planned Activities include ships,
submarines, unmanned vessels, and boats ranging in size from small, 22
ft (7 m) rigid hull inflatable boats to aircraft carriers with lengths
up to 1,092 ft (333 m). The average speed of large Navy ships ranges
between 10 and 15 knots and submarines generally operate at speeds in
the range of 8-13 knots, while a few specialized vessels can travel at
faster speeds. Small craft (for purposes of this analysis, less than 18
m in length) have much more variable speeds (0-50+ knots (kn),
dependent on the activity), but generally range from 10 to 14 kn. From
unpublished Navy data, average median speed for large Navy ships in the
HSTT Study Area from 2011-2015 varied from 5-10 kn with variations by
ship class and location (i.e., slower
[[Page 66872]]
speeds close to the coast). While these speeds for large and small
craft are representative of most events, some vessels need to
temporarily operate outside of these parameters.
The number of Navy vessels used in the HSTT Study Area varies based
on military training and testing requirements, deployment schedules,
annual budgets, and other dynamic factors. Most training and testing
activities involve the use of vessels. These activities could be widely
dispersed throughout the HSTT Study Area, but would be typically
conducted near naval ports, piers, and range areas. Navy vessel traffic
would especially be concentrated near San Diego, California and Pearl
Harbor, Hawaii. There is no seasonal differentiation in Navy vessel use
because of continual operational requirements from Combatant
Commanders. The majority of large vessel traffic occurs between the
installations and the OPAREAs. Support craft would be more concentrated
in the coastal waters in the areas of naval installations, ports, and
ranges. Activities involving vessel movements occur intermittently and
are variable in duration, ranging from a few hours up to weeks.
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 a real-world situation 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 additional benefits to
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
activities, and has included them in the environmental analysis.
Additional details on standard operating procedures were provided in
our Federal Register notice of proposed rulemaking (83 FR 29872; June
26, 2018); please see that notice of proposed rulemaking or the Navy's
application for more information.
Duration and Location
Training and testing activities would be conducted under this
authorization in the HSTT Study Area throughout the years. The HSTT
Study Area (see Figure 1.1-1 of the Navy's rulemaking/LOA application)
is comprised of established operating and warning areas across the
north-central Pacific Ocean, from the mean high tide line in Southern
California west to Hawaii and the International Date Line. The Study
Area includes the at-sea areas of three existing range complexes (the
Hawaii Range Complex, the SOCAL Range Complex, and the Silver Strand
Training Complex), and overlaps a portion of the PMSR. Also included in
the Study Area are Navy pierside locations in Hawaii and Southern
California, Pearl Harbor, San Diego Bay, and the transit corridor \2\
on the high seas where sonar training and testing may occur.
---------------------------------------------------------------------------
\2\ Vessel transit corridors are the routes typically used by
Navy assets to traverse from one area to another. The route depicted
in Figure 1-1 of the Navy's rulemaking/LOA application is the
shortest route between Hawaii and Southern California, making it the
quickest and most fuel efficient. The depicted vessel transit
corridor is notional and may not represent the actual routes used by
ships and submarines transiting from Southern California to Hawaii
and back. Actual routes navigated are based on a number of factors
including, but not limited to, weather, training, and operational
requirements.
---------------------------------------------------------------------------
A Navy range complex consists of geographic areas that encompass a
water component (above and below the surface) and airspace, and may
encompass a land component where training and testing of military
platforms, tactics, munitions, explosives, and electronic warfare
systems occur. Range complexes include OPAREAs and special use
airspace, which may be further divided to provide better control of the
area and events being conducted for safety reasons. Please refer to the
regional maps provided in the Navy's rulemaking/LOA application
(Figures 2-1 through 2-8) for additional detail of the range complexes
and testing ranges. Additional detail on range complexes and testing
ranges was provided in our Federal Register notice of proposed
rulemaking (83 FR 29872; June 26, 2018); please see that notice of
proposed rulemaking or the Navy's application for more information.
Comments and Responses
We published a notice of proposed regulations in the Federal
Register on June 26, 2018 (83 FR 29872), with a 45-day comment period.
In that notice of proposed rulemaking, we requested public input on the
requests for authorization described therein, our analyses, and the
proposed authorizations, and requested that interested persons submit
relevant information, suggestions, and comments. During the 45-day
comment period, we received 22 comment letters in total. Of this total,
two submissions were from other Federal agencies, two letters were from
organizations or individuals acting in an official capacity (e.g., non-
governmental organizations (NGOs)) and 18 submissions were from private
citizens. NMFS has reviewed all public comments received on the
proposed rule and issuance of the LOAs. All relevant comments and our
responses are described below. We provide no response to specific
comments that addressed species or statutes not relevant to our
proposed actions under section 101(a)(5)(A) of the MMPA (e.g., comments
related to sea turtles). We organize our comment responses by major
categories.
General Comments
The majority of the 18 comment letters from private citizens
expressed general opposition toward the Navy's proposed training and
testing activities and requested that NMFS not issue the LOAs, but
without providing information relevant to NMFS' decisions. These
comments appear to indicate a lack of understanding of the MMPA's
requirement that NMFS ``shall issue'' requested authorizations when
certain findings (see the Background section) can be made; therefore,
these comments were not considered further. The remaining comments are
addressed below.
Impact Analysis
General
Comment 1: A commenter recommended that the Navy provide NMFS with
an acoustics analysis that addresses noise impacts on land, from the
air, and underwater. Full environmental analysis of the noise would
examine a suite of metrics appropriate to the array of resources
impacted. The impacts should discuss potential effects on wildlife,
visitors, and other noise-sensitive receivers.
The commenter also recommended that the Navy consider the following
as it plans to conduct activities in the HSTT Study Area:
Use appropriate metrics to assess potential
environmental impacts on land and water.
Determine natural ambient acoustic conditions as a
baseline for analysis.
Assess effects from cumulative noise output,
incorporating noise generated from other anthropogenic sources.
Determine distance at which noise will attenuate to
natural levels.
Assess effects that these noise levels would have on
terrestrial wildlife, marine wildlife, and visitors.
Appropriate and effective mitigation measures should be
developed and used to reduce vessel strike (e.g., timing activities
to avoid migration, and searching for marine
[[Page 66873]]
mammals before and during activities and taking avoidance measures).
Response: NMFS refers the commenter to the HSTT FEIS/OEIS which
conducts an assessment of all of the activities which comprise the
proposed action and their impacts (including cumulative impacts) to
relevant resources. The Navy is not required to do ambient noise
monitoring or assess impacts to wildlife other than marine mammals or
to visitors/tourists. The mitigation measures in the rule include
procedural measures to minimize strike (avoiding whales by 500 yards,
etc.), mitigation areas to minimize strike in biologically important
areas, and Awareness Notification Message areas wherein all vessels are
alerted to stay vigilant to the presence of large whales.
Density Estimates
Comment 2. A commenter commented that 30 iterations or Monte Carlo
simulations is low for general bootstrapping methods used in those
models but understands that increasing the number of iterations in turn
increases the computational time needed to run the models. Accordingly,
the commenter suggested that the Navy consider increasing the
iterations from 30 to at least 200 for activities that have yet to be
modeled for upcoming MMPA rulemakings for Navy testing and training
activities.
Response: In areas where there are four season, 30 iterations are
used in NAEMO which results in a total of 120 iterations per year for
each event. However, in areas where only two seasons, warm and cold,
the number of iterations per season is increased to 60 so that 120
iterations per year are maintained. Navy reached this number of
iterations by running two iterations of a scenario and calculating the
mean of exposures, then running a third iteration and calculating the
running mean of exposures, then a fourth iteration and so on. This is
done until the running mean becomes stable. Through this approach, it
was determined 120 iterations was sufficient to converge to a
statistically valid answer and provides a reasonable uniformity of
exposure predictions for most species and areas. There are a few
exceptions for species with sparsely populated distributions or highly
variable distributions. In these cases, the running mean may not
flatten out (or become stable); however, there were so few exposures in
these cases that while the mean may fluctuate, the overall number of
exposures did not result in significant differences in the totals. In
total, the number of simulations conducted for HSTT Phase III exceeded
six million simulations and produced hundreds of terabytes of data.
Increasing the number of iterations, based on the discussion above,
would not result in a significant change in the results, but would
incur a significant increase in resources (e.g., computational and
storage requirements). This would divert these resources from
conducting other more consequential analysis without providing for
meaningfully improved data. The Navy has communicated that it is
continually looking at ways to improve NAEMO and reduce data and
computational requirements. As technologies and computational
efficiencies improve, Navy will evaluate these advances and incorporate
them where appropriate. NMFS has reviewed the Navy's approach and
concurs that it is technically sound and reflects the best available
science.
Comment 3: A commenter had concerns regarding the Navy's pinniped
density estimates. Given that a single density was provided for the
respective areas and pinnipeds were assumed to occur at sea as
individual animals, uncertainty does not appear to have been
incorporated in the Navy's animat modeling for pinnipeds. The Navy
primarily used sightings or abundance data, assuming certain correction
factors, divided by an area to estimate pinniped densities. Many, if
not all, of the abundance estimates had associated measures of
uncertainty (i.e., coefficients of variation (CV), standard deviation
(SD), or standard error (SE)). Therefore, the commenter recommended
that NMFS require the Navy to specify whether and how it incorporated
uncertainty in the pinniped density estimates into its animat modeling
and if it did not, require the Navy to use measures of uncertainty
inherent in the abundance data (i.e., CV, SD, SE) similar to the
methods used for cetaceans.
Response: As noted in the cited 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, 2017a), the Navy did not apply statistical uncertainty
outside the survey boundaries into non-surveyed areas, since it deemed
application of statistical uncertainty would not be meaningful or
appropriate. We note that there are no measures of uncertainty (i.e.,
no CV, SD, or SE) provided in NMFS Pacific Stock Assessment Report
(SAR) Appendix 3 (Carretta et al., 2017) associated with the abundance
data for any of the pinniped species present in Southern California or
for monk seals in Hawaii. Although some measures of uncertainty are
presented in some citations within the SAR and in other relevant
publications for some survey findings, it is not appropriate for the
Navy to attempt to derive summations of total uncertainty for an
abundance when the authors of the cited studies and the SAR have not.
For additional information regarding use of pinniped density data, see
the cited U.S. Navy Marine Species Density Database Phase III for the
Hawaii-Southern California Training and Testing Study Area Section 11
(U.S. Department of the Navy, 2017b). As a result of the lack of
published applicable measures of uncertainty for pinnipeds, the Navy
did not incorporate measures of uncertainty into the pinniped density
estimates. NMFS independently reviewed the methods and densities used
by the Navy and concur that they are appropriate and reflect the best
available science.
Comment 4: A commenter had concerns regarding the various areas,
abundance estimates, and correction factors that the Navy used for
pinnipeds. The commenter referenced a lot of information in the context
of both what the Navy used and what they could have used instead and
summarizes the discussion with seven recommendations.
For harbor seals, the area was based on the NMFS SOCAL stratum
(extending to the extent of the U.S. exclusive economic zone (EEZ), 370
km from the coast) for its vessel-based surveys (i.e., Barlow 2010) and
the Navy applied the density estimates from the coast to 80-km
offshore. The commenter believes that this approach is inappropriate
and that the Navy should use the area of occurrence to estimate the
densities for harbor seals. For harbor seals, the Navy assumed that 22
percent of the stock occurred in SOCAL, citing Department of the Navy
(2015). The commenter had two concerns with this approach. First, one
has to go to Department of the Navy (2015) to determine the original
source of the information (Lowry et al., 2008; see the commenter's
February 20, 2014, letter on this matter). Second, Lowry et al. (2008)
indicated that 23.3 percent of the harbor seal population occurred in
SOCAL, not 22 percent as used by the Navy. Therefore, the commenter
recommended that, at the very least, NMFS require the Navy to revise
the pinniped density estimates using the extent of the coastal range
(e.g., from shore to 80 km offshore) of harbor seals as the applicable
area, 23.3 percent of the California abundance estimate based on Lowry
et al. (2008), and an at-sea correction factor of 65 percent based on
[[Page 66874]]
Harvey and Goley (2011) for both seasons.
For Monk seals the area was based on the areas within the 200-m
isobaths in both the Main and Northwest Hawaiian Islands (MHI and NWHI,
respectively) and areas beyond the 200-m isobaths in the U.S. EEZ. The
commenter asserted that some of the abundances used were not based on
best available science. The Navy noted that its monk seal abundance was
less than that reported by Baker et al. (2016), but that those more
recent data were not available when the Navy's modeling process began.
The Baker et al. (2016) data have been available for almost two years
and should have been incorporated accordingly, particularly since the
data would yield greater densities and the species is endangered. For
monk seals, the commenter recommended using the 2015 monk seal
abundance estimate from Baker et al. (2016) and an at-sea correction
factor of 63 percent for the MHI based on Baker et al. (2016) and 69
percent for the NWHI based on Harting et al. (2017).
For the northern fur seals, the area was based on the NMFS SOCAL
stratum (extending to the extent of the U.S. EEZ, 370 km from the
coast) for its vessel-based surveys (i.e., Barlow 2010). For elephant
seals, California sea lions, and Guadalupe fur seals, the area was
based on the Navy SOCAL modeling area. The commenter had concerns that
these areas are not based on the biology or ecology of these species.
The commenter recommended using the same representative area for
elephant seals, northern fur seals, Guadalupe fur seals, and California
sea lions. The commenter recommended using an increasing trend of 3.8
percent annually for the last 15 years for elephant seals as part of
the California population and at least 31,000 as representative of the
Mexico population based on Lowry et al. (2014). Additionally, the
commenter recommended using an at-sea correction factor of 44 percent
for the cold season and 48 percent for the warm season for California
sea lions based on Lowry and Forney (2005).
Finally, the commenter recommended that NMFS require the Navy to
(1) specify the assumptions made and the underlying data that were used
for the at-sea correction factors for Guadalupe and northern fur seals
and (2) consult with experts in academia and at the NMFS Science
Centers to develop more refined pinniped density estimates that account
for pinniped movements, distribution, at-sea correction factors, and
density gradients associated with proximity to haul-out sites or
rookeries.
Response: The Navy provided additional clarification regarding the
referenced concerns about areas, abundance estimates, and correction
factors that were used for pinnipeds. We 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. Different methods may be supportable in different
situations, and, further, there may be more than one acceptable method
to estimate take in a particular situation. Accordingly, while NMFS
always ensures that the 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. We note the following in
further support of the analysis: 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 and, further, would not change NMFS'
determinations for pinnipeds. In addition, we note that (1) many of the
specific recommendations that the commenter makes are largely minor in
nature: ``44 not 47 percent,'' ``63 not 61 percent,'' ``23.3 not 22
percent'' or ``area being approximately 13 percent larger;'' and (2)
even where the recommendation is somewhat larger in scale, given the
ranges 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 recruitment or survival
of any of these stocks, or the negligible impact determination. Below,
we address the Commenters 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.
For harbor seals--Based on the results from satellite tracking of
harbor seals at Monterey, California and the documented dive depths
(Eguchi and Harvey, 2005), the extent of the range for harbor seals in
the HSTT Study Area used by the Navy (a 50 nmi buffer around all known
haul-out sites; approximately 93 km) is more appropriate than the
suggested 80 km offshore suggested by commenter.
The comment is incorrect in its claim that the Navy did not use the
best available science. Regarding the appropriate percentage of the
California Current Ecosystem abundance to assign to the HSTT Study
Area, the 22 percent that the Navy used is based on the most recent of
the two years provided in Lowry et al. (2008) rather than the mean of
two years, which is one valid approach. Additionally, since
approximately 74 percent of the harbor seal population in the Channel
Islands (Lowry et al., 2017) is present outside and to the north of the
HSTT Study Area, it is a reasonable assumption that the 22 percent used
already provides a conservative overestimate and that it would not be
appropriate to apply a higher percentage of the overall population for
distribution into the Navy's modeling areas.
Again the comment is incorrect in its claim that the correction
factors applied to population estimates were either unsubstantiated or
incorrect. Regarding the commenter's recommended use of an at-sea
correction factor of 65 percent for both seasons based on Harvey and
Goley (2011), that correction factor was specifically meant to apply to
the single molting season when harbor seals are traditionally surveyed
(see discussion in Lowry et al., 2017). Additionally, the authors of
that study provided a correction factor (CF = 2.86; 35 percent) for
Southern California but left open the appropriateness of that factor
given the limited data available at the time. For these reasons, having
separate correction factors for each of the seasons is more appropriate
as detailed in Section 11.1.5 (Phoca vitulina, Pacific harbor seal) of
the U.S. Navy Marine Species Density Database Phase III for the Hawaii-
Southern California Training and Testing Study Area (U.S. Department of
the Navy, 2017b).
For monk seals, as detailed in Section 11.1.4 (Neomonachus
schauinslandi, Hawaiian monk seal) of the U.S. Navy Marine Species
Density Database Phase III for the Hawaii-Southern California Training
and Testing Study Area (U.S. Department of the Navy, 2017b), the Navy
consulted with the researchers and subject matter experts at the
Pacific Science Center and the Monk Seal Recovery Team regarding the
abundance estimates, at sea correction factors, and distribution for
monk seals in the Hawaiian Islands during development
[[Page 66875]]
of the HSTT FEIS/OEIS throughout 2015 and the Summer of 2016. The Navy
incorporated the results of those consultations, including unpublished
data, into the analysis of monk seals. Additional details in this
regard to monk seal distributions and population trends as reflected by
the abundance in the Hawaiian Islands are presented in the FEIS/OEIS in
Section 3.7.2.2.9.2 (Habitat and Geographic Range) and Section
3.7.2.2.9.3 (Population Trends). The Navy has indicated that it has
continued ongoing communications with researchers at the Pacific
Islands Science Center and elsewhere, has accounted for the findings in
the citations noted by the commenter (Baker et al., 2016; Harting et
al., 2017) as well as information in forthcoming publications provided
ahead of publication via those researchers (cited as in preparation),
and specifically asked for and received concurrence from subject matter
experts regarding specific findings presented in the HSTT FEIS/OEIS
regarding monk seals. The Navy also considered (subsequent to
publication of the HSTT FEIS) the new Main Hawaiian Islands haulout
correction factor presented in the publication by Wilson et al. (2017,
which would be inconsistent with the use of the Baker et al. (2016)
correction factors suggested by the commenter), and the Harting et al.
(2017) correction factor, and has considered the new abundance numbers
presented in the 2016 Stock Assessment Report, which first became
available in January 2018. It is the Navy's assessment that a revision
of the monk seal at-sea density would only result in small changes to
the predicted effects and certainly would not change the conclusions
presented in the HSTT FEIS/OEIS regarding impact on the population or
the impact on the species. The Navy has communicated that it assumes
that as part of the ongoing regulatory discussions with NMFS, changes
to estimates of effects can be best dealt with in the next rulemaking
given Wilson et al. (2017) has now also provided a totally new haulout
correction factor for the Main Hawaiian Islands that was not considered
in Baker et al. (2016), Harting et al. (2017), or the 2016 SAR.
For northern fur seals, elephant seals, California sea lions, and
Guadalupe fur seals, the Navy consulted with various subject matter
experts regarding the abundances and distributions used in the HSTT
FEIS/OEIS analyses for these species and based on those consultations
and the literature available, the Navy and NMFS believe that the
findings presented in the HSTT FEIS/OEIS and supporting technical
reports provide the most accurate assessments available for these
species. Given the demonstrated differences in the at-sea distributions
of elephant seals, northern fur seals, Guadalupe fur seals, and
California sea lions (Gearin et al., 2017; Lowry et al., 2014; Lowry,et
al., 2017; Norris, 2017; Norris,et al., 2015; Robinson et al., 2012;
University of California Santa Cruz and National Marine Fisheries
Service, 2016), it would not be appropriate to use the same
representative area for distributions of these species' population
abundances. For example, California sea lions forage predominantly
within 20 nautical miles from shore (Lowry and Forney, 2005), while tag
data shows that many elephant seals (Robinson et al., 2012) and
Guadalupe fur seals (Norris, 2017) seasonally forage in deep waters of
the Pacific well outside the boundaries of the HSTT Study Area.
For northern elephant seals (Mirounga angustirostris, Northern
elephant seal), as detailed in Section 11.1.3 of the technical report
titled U.S. Navy Marine Species Density Database Phase III for the
Hawaii-Southern California Training and Testing Study Area (U.S.
Department of the Navy, 2017e), hereafter referred to as the Density
Technical Report, the Navy considered a number of factors in the
development of the data for this species, including the fact that not
all of the elephant seal population is likely to occur exclusively
within the Southern California portion of the HSTT Study Area. Given
that the three main rookeries considered in this analysis are located
at the northern boundary of the HSTT Study Area and that elephant seals
migrate northward after the breeding season, the Navy, in consultation
with subject matter experts, believes the current abundance used in the
analysis is based on the best available science and represents a
conservative overestimate of the number of elephant seals likely to be
affected by Navy activities in the HSTT Study Area.
For California sea lions, the citation (Lowry and Forney, 2005)
used as the basis for this recommendation specifically addressed the
use of the Central and Northern California at-sea correction factor
elsewhere, with the authors stating; ``In particular, [use of the
Central and Northern California at-sea correction factor] would not be
appropriate for regions where sea lions reproduce, such as in the
Southern California Bight (SCB) and in Mexico, . . .'' Given the waters
of the Southern California Bight and off Mexico overlap the HSTT Study
Area and since the authors of the cited study specifically recommended
not using the correction factor in the manner the commenter suggested,
the Navy does not believe use of that correction factor for the HSTT
Study Area would be appropriate. NMFS concurs with this approach
For Guadalupe fur seal--Additional detail regarding the data used
for the analysis of Guadalupe fur seals has been added to the HSTT
Final EIS/OEIS Section 3.7.2.2.8 (Arctocephalus townsendi, Guadalupe
Fur Seal). The Navy had integrated the latest (September 2017)
unpublished data for Guadalupe fur seals from researchers in the United
States and Mexico into the at-sea correction factor and density
distribution of the species used in the modeling, but consultations
with experts in academia and at the NMFS Science Centers and their
recommendations had not been finalized before release of the Draft EIS/
OEIS. Subsequently, the Navy did not consider this revision of the text
critical for the final NEPA document since the new data did not provide
any significant change to the conclusions reached regarding the
Guadalupe fur seal population. In fact, the data indicates an increase
in the population and expansion of their range concurrent with decades
of ongoing Navy training and testing in the SOCAL range complex.
For Northern Fur Seal--As presented in Section 11.1.2 (Callorhinus
ursinus, Northern fur seal) of the Navy's Density Technical Report
(U.S. Department of the Navy, 2017b), the correction factor percentages
for northern fur seals potentially at sea were derived from the
published literature as cited (Antonelis, Stewart, & Perryman, 1990;
Ream, Sterling, & Loughlin, 2005; Roppel, 1984).
For future EISs, the Navy explained that it did and will continue
to consult with authors of the papers relevant to the analyses as well
as other experts in academia and at the NMFS Science Centers during the
development of the Navy's analyses. During the development of the HSTT
EIS/OEIS and as late as September 2017, the Navy had ongoing
communications with various subject matter experts and specifically
discussed pinniped movements, the distribution of populations within
the study area to support the analyses, the pinniped haulout or at-sea
correction factors, and the appropriateness of density gradients
associated with proximity to haul-out sites or rookeries. As shown in
the references cited, the personal communications with researchers have
been made part of the public record, although many other
[[Page 66876]]
informal discussions with colleagues have also assisted in the Navy's
approach to the analyses presented.
The Navy acknowledges that there have been previous comments
provided by this commenter on other Navy range complex documents
regarding the use of satellite tag movement and location data to derive
at-sea pinniped density data, and the Navy asserts that previous
responses to those comments remain valid. Additionally, the commenter
has noted that the ``. . . Commenter continues to believe that data
regarding movements and dispersion of tagged pinnipeds could yield
better approximations of densities than the methods the Navy currently
uses.'' The Navy acknowledges that in comments to previous Navy EIS/
OEIS analyses, the commenter has recommended this untried approach;
responses to those previous comments have been provided. The Navy also
notes that there have been papers suggesting the future application of
Bayesian or Markov chain techniques for use in habitat modeling (e.g.,
Redfern et al., 2006) and overcoming the bias introduced by
interpretation of population habitat use based on non-randomized
tagging locations (e.g., Whitehead & Jonsen, 2013). However, the use of
satellite tag location data in a Bayesian approach to derive cetacean
or pinniped densities at sea has yet to be accepted, implemented, or
even introduced in the scientific literature.
This issue was in fact recently discussed as part of the Density
Modeling Workshop associated with the October 2017 Society for Marine
Mammalogy conference. The consensus of the marine mammal scientists
present was that while pinniped tag data could provide a good test
case, it realistically was unlikely to be a focus of the near-term
research. The working group determined that a focused technical group
should be established to specifically discuss pinnipeds and data
available for density surface modelling in the future. It was also
discussed at the Density Modeling Workshop in October 2018. The Navy
has convened a pinniped working group and NMFS ASFSC is sponsoring a
demonstration project to use haulout and telemetry data from seals in
Alaska to determine the viability of such an approach.
Therefore, consistent with previous assessments and based on recent
discussions with subject matter experts in academia, the NMFS Science
Centers, and the National Marine Mammal Laboratory, and given there is
no currently established methodology for implementing the approach
suggested by the commenter, the Navy believes that attempting to create
and apply a new density derivation method at this point would introduce
additional levels of uncertainty into density estimations.
For these reasons, the Navy and NMFS will not provide density
estimates based on pinniped tracking data. Publications reporting on
satellite tag location data have been and will continue to be used to
aid in the understanding of pinniped distributions and density
calculations as referenced in the FEIS/OEIS and the U.S. Navy Marine
Species Density Database Phase III for the Hawaii-Southern California
Training and Testing Study Area (U.S. Department of the Navy, 2017b).
The Navy has communicated that it will continue, as it has in the past,
to refine pinniped density and distributions using telemetry data and
evolving new techniques (such as passive acoustic survey data) in
development of the Navy's analyses. As noted above, NMFS has reviewed
the Navy's methods and concurs that they are appropriate and reflect
the best available science.
Comment 5: A commenter recommended that NMFS require the Navy to
(1) specify what modeling method and underlying assumptions, including
any relevant source spectra and assumed animal swim speeds and turnover
rates, were used to estimate the ranges to PTS and TTS for impact and
vibratory pile-driving activities, (2) accumulate the energy for the
entire day of proposed activities to determine the ranges to PTS and
TTS for impact and vibratory pile-driving activities, and (3) clarify
why the PTS and TTS ranges were estimated to be the same for LF and HF
cetaceans during impact pile driving.
Response: As explained in Section 3.7.3.1.4.1 of the HSTT FEIS/
OEIS, the Navy measured values for source levels and transmission loss
from pile driving of the Elevated Causeway System, the only pile
driving activity included in the Specified Activity. The Navy reviewed
the source levels and how the spectrum was used to calculate the range
to effects; NMFS supports the use of these measured values. These
recorded source waveforms were weighted using the auditory weighting
functions. Low-frequency and high-frequency cetaceans have similar
ranges for impact pile driving since low-frequency cetaceans would be
relatively more sensitive to the low-frequency sound which is below
high-frequency cetaceans' best range of hearing. Neither the NMFS user
spreadsheet nor NAEMO were required for calculations. An area density
model was developed in MS Excel which calculated zones of influence
(ZOI) to thresholds of interest (e.g., behavioral response) based on
durations of pile driving and the aforementioned measured and weighted
source level values. The resulting area was then multiplied by density
of each marine mammal species that could occur within the vicinity.
This produced an estimated number of animals that could be impacted per
pile, per day, and overall during the entire activity for both the
impact pile driving and vibratory removal phases. NOAA HQ scientists
involved in the acoustic criteria development reviewed the manner in
which the Navy applied the frequency weighting and calculated all
values and concurred with the approach.
Regarding the appropriateness of accumulating energy for the entire
day, based on the best available science regarding animal reaction to
sound, selecting a reasonable SEL calculation period is necessary to
more accurately reflect the time period an animal would likely be
exposed to the sound. The Navy factored both mitigation effectiveness
and animal avoidance of higher sound levels into the impact pile
driving analysis. For impact pile driving, the mitigation zone extends
beyond the average ranges to PTS for all hearing groups; therefore,
mitigation will help prevent or reduce the potential for exposure to
PTS. The impact pile driving mitigation zone also extends beyond or
into a portion of the average ranges to TTS; therefore, mitigation will
help prevent or reduce the potential for exposure to all TTS or some
higher levels of TTS, depending on the hearing group. Mitigation
effectiveness and animal avoidance of higher sound levels were both
factored into the impact pile driving analysis as most marine mammals
should be able to easily move away from the expanding ensonified zone
of TTS/PTS within 60 seconds, especially considering the soft start
procedure, or avoid the zone altogether if they are outside of the
immediate area upon startup. Marine mammals are likely to leave the
immediate area of pile driving and extraction activities and be less
likely to return as activities persist. However, some ``naive'' animals
may enter the area during the short period of time when pile driving
and extraction equipment is being re-positioned between piles.
Therefore, an animal ``refresh rate'' of 10 percent was selected. This
means that 10 percent of the single pile ZOI was added for each
consecutive pile within a given 24-hour period to generate the daily
ZOI per effect category. These daily ZOIs were then multiplied by the
number of days of pile driving and pile extraction and
[[Page 66877]]
then summed to generate a total ZOI per effect category (i.e.,
behavioral response, TTS, PTS). The small size of the mitigation zone
and its close proximity to the observation platform will result in a
high likelihood that Lookouts would be able to detect marine mammals
throughout the mitigation zone.
PTS/TTS Thresholds
Comment 6: A commenter supported the weighting functions and
associated thresholds as stipulated in Finneran (2016), which are the
same as those used for Navy Phase III activities, but points to
additional recent studies that provide additional behavioral audiograms
(e.g., Branstetter et al. 2017; Kastelein et al. 2017b) and information
on TTS (e.g., Kastelein et al. 2017a, 2017c). However, they commented
that the Navy should provide a discussion of whether those new data
corroborate the current weighting functions and associated thresholds.
Response: The NMFS Revised Technical Guidance for Assessing the
Effects of Anthropogenic Sound on Marine Mammal Hearing (NMFS 2018)
(Acoustic Technical Guidance), which was used in the assessment of
effects for this action, compiled, interpreted, and synthesized the
best available scientific information for noise-induced hearing effects
for marine mammals to derive updated thresholds for assessing the
impacts of noise on marine mammal hearing, including the articles that
the commenter referenced that were published subsequent to the
publication of the first version of 2016 Acoustic Technical Guidance.
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).
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. Thus far, no new information has been published or
otherwise conveyed that would fundamentally change the assessment of
impacts or conclusions of this rule.
Comment 7: Commenters commented that the criteria that the agency
has produced to estimate temporary threshold shift (TTS) and permanent
threshold shift (PTS) in marine mammals are erroneous and non-
conservative. Commenters cited multiple purported issues with NMFS'
Acoustic Technical Guidance, such as pseudo-replication and
inconsistent treatment of data, broad extrapolation from a small number
of individuals, and disregarding ``non-linear accumulation of
uncertainty.'' Commenters suggested that NMFS not rely exclusively on
its auditory guidance for determining Level A harassment take, but
should at a minimum retain the historical 180-dB rms Level A harassment
threshold as a ``conservative upper bound'' or conduct a ``sensitivity
analysis'' to ``understand the potential magnitude'' of the supposed
errors.
Response: NMFS disagrees with this characterization of the Acoustic
Technical Guidance and the associated recommendation. The Acoustic
Technical Guidance is a compilation, interpretation, and synthesis of
the scientific literature that provides the best scientific information
regarding the effects of anthropogenic sound on marine mammals'
hearing. The technical guidance was classified as a Highly Influential
Scientific Assessment and, as such, underwent three independent peer
reviews, at three different stages in its development, including a
follow-up to one of the peer reviews, prior to its dissemination by
NMFS. In addition, there were three separate public comment periods,
during which time we received and responded to similar comments on the
guidance (81 FR 51694), which we cross-reference here, and more recent
public and interagency review under Executive Order 13795. This review
process was scientifically rigorous and ensured that the Guidance
represents the best scientific data available.
The Acoustic Technical Guidance updates the historical 180 dB rms
injury threshold, which was based on professional judgement (i.e., no
data were available on the effects of noise on marine mammal hearing at
the time this original threshold was derived). NMFS disagrees with any
suggestion that the use of the Acoustic Technical Guidance provides
erroneous results. The 180-dB rms threshold is plainly outdated, as the
best available science indicates that rms SPL is not even an
appropriate metric by which to gauge potential auditory injury (whereas
the scientific debate regarding behavioral harassment thresholds is not
about the proper metric but rather the proper level or levels and how
these may vary in different contexts).
Multiple studies from humans, terrestrial mammals, and marine
mammals have demonstrated less 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 pseudo-replication 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 behavioral temporary threshold shift studies,
behaviorally derived data are only available for two mid-frequency
cetacean species (bottlenose dolphin, beluga) and two phocids (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. 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
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
[[Page 66878]]
much a sound level needs to be above 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.
Behavioral Harassment Thresholds
Comment 8: Commenters commented on what it asserts is NMFS' failure
to set proper thresholds for behavioral impacts. Referencing the
biphasic function that assumes an unmediated dose response relationship
at higher received levels and a context-influenced response at lower
received levels that NMFS uses to quantify behavioral harassment from
sonar, Commenters commented that resulting functions depend on some
inappropriate assumptions that tend to significantly underestimate
effects. Commenters expressed concern that every data point that
informs the agency's pinniped function, and nearly two-thirds of the
data points informing the odontocete function (30/49), are derived from
a captive animal study. Additionally, Commenters asserted that the risk
functions do not incorporate (nor does NMFS apparently consider) a
number of relevant studies on wild marine mammals. Commenters stated
that it is not clear from the proposed rule, or from the Navy's recent
technical report on acoustic ``criteria and thresholds,'' on which
NMFS' approach in the rule is based, exactly how each of the studies
that NMFS employed was applied in the analysis, or how the functions
were fitted to the data, but the available evidence on behavioral
response raises concerns that the functions are not conservative for
some species. Commenters recommended NMFS make additional technical
information available, including from any expert elicitation and peer
review, so that the public can fully comment.
Response: The Criteria and Thresholds for U.S. Navy Acoustic and
Explosive Impacts to Marine Mammals and Sea Turtles Technical Report
(U.S. Department of the Navy, 2017) details how the Navy's proposed
method, which was determined appropriate and adopted by NMFS, accounted
for the differences in captive and wild animals in the development of
the behavioral response functions. The Navy used the best available
science, which has been reviewed by external scientists and approved by
NMFS, in the analysis. The Navy and NMFS have utilized all available
data that relate known or estimable received levels to observations of
individual or group behavior as a result of sonar exposure (which is
needed to inform the behavioral response function) for the development
of updated thresholds. Limiting the data to the small number of field
studies that include these necessary data would not provide enough data
with which to develop the new risk functions. In addition, NMFS agrees
with the assumptions made by the Navy, including the fact that captive
animals may be less sensitive, in that 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 agency 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. As new science
is published, NMFS and the Navy continue to evaluate the information.
The thresholds have been rigorously vetted among scientists and within
the Navy community 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.
These new and future papers provide additional information, and the
Navy has already begun to consult them for updates to the thresholds 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 HSTT FEIS/OEIS or this rule. To be included in the
behavioral response function, data sets need 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.
As noted, the derivation of the behavioral response functions is
provided in the 2017 technical report titled Criteria and Thresholds
for U.S. Navy Acoustic and Explosive Effects Analysis (Phase III). The
appendices to this report detail the specific data points used to
generate the behavioral response functions. Data points come from
published data that is readily available and cited within the technical
report.
Comment 9: Commenters stated concerns with the use of distance
``cut-offs'' in the behavioral harassment thresholds, and one commenter
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.
Response: The consideration of proximity (cut-off distances) was
part of the criteria developed in consultation between the Navy and
NMFS, is appropriate based on the best available science which shows
that marine mammal responses to sound vary based on both sound level
and distance, and was applied within the Navy's acoustic effects model.
The derivation of the behavioral response functions 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 is not available
for a given species group) were reviewed to find the farthest distance
to which significant behavioral reactions were observed. 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 of
impact and potential take under military readiness for the actions
analyzed within the HSTT FEIS/OEIS and included in these regulations.
NMFS has independently assessed the Navy's behavioral harassment
thresholds and believes that they appropriately apply the best
available science and it is not necessary to recalculate take
estimates.
The commenter also specifically expressed concern that distance
``cut-offs'' alleviate some of the exposures that would otherwise have
been counted if the received level alone were considered. It is unclear
why the commenter finds this inherently inappropriate, as this is what
the data show. As noted previously, there are
[[Page 66879]]
multiple studies illustrating that in situations where one would expect
a behavioral harassment 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 10: Regarding cut-off distances, Commenters noted that
dipping sonar appears to be a significant predictor of deep-dive rates
in beaked whales on Southern California Anti-submarine Warfare Range
(SOAR), 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. Importantly, these effects
were observed at substantially greater distances (e.g., 30 or more km)
from dipping sonar than would otherwise be expected given the systems'
source levels and the beaked whale response thresholds developed from
research on hull-mounted sonar. Commenters suggested that the analysis,
and associated cut-off distances, do not properly consider the impacts
of dipping sonar.
Response: The Navy relied upon the best science that was available
to develop the behavioral response functions in consultation with NMFS.
The Navy's 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.
The referenced article (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 proposed rule was published would
significantly change the assessment of impacts or conclusions in the
HSTT FEIS/OEIS or in this rulemaking. Nonetheless, the new information
and data presented in the new article were recently thoroughly reviewed
by the Navy and will be quantitatively incorporated into future
behavioral response functions, as appropriate for data available at the
time that new functions are needed to inform new analyses.
Furthermore, ongoing Navy funded 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 eight
years of monitoring (DiMarzio et al., 2018). From visual surveys in the
area since 2006 there have been repeated sightings of: The same
individual beaked whale, beaked whale mother-calf pairs, and beaked
whale mother-calf pairs with mothers on their second calf (Schorr et
al., 2018). Satellite tracking studies of beaked whale documented high
site fidelity to this area (Schorr et al., 2018).''
Comment 11: Regarding the behavioral thresholds for explosives,
Commenters recommended that NMFS estimate and ultimately authorize
behavior takes of marine mammals during all explosive activities,
including those that involve single detonations.
Response: 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), and
NMFS has applied the general rule a commenter referenced to single
explosives for years, i.e., that marine mammals are unlikely to respond
to a single instantaneous detonation in a manner that would rise to the
level of a take. Neither NMFS nor the Navy are aware of evidence to
support the assertion that animals will have significant behavioral
reactions (i.e., those that would rise to the level of a take) to
temporally and spatially isolated explosions. The Navy has been
monitoring detonations since the 1990s and has not observed these types
of reactions. TTS and all other higher order impacts are assessed for
all training and testing events that involve the use of explosives or
explosive ordnance.
Further, to clarify, the current take estimate framework does not
preclude the consideration of animals being behaviorally disturbed
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 behaviorally harassed and those potential impacts are considered in
the negligible impact determination.
All of the Navy's monitoring projects, reports, and publications
are available on the marine species monitoring web page (https://www.navymarinespeciesmonitoring.us/). NMFS will continue to review
applicable monitoring and science data and consider modifying these
criteria when and if new information suggests it is appropriate.
Mortality and injury thresholds for explosions
Comment 12: A commenter recommended that NMFS require the Navy to
(1) explain why the constants and exponents for onset mortality and
onset slight lung injury thresholds for Phase III have been amended,
(2) ensure that the modified equations are correct, and (3) specify any
additional assumptions that were made.
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). It is our understanding that the
constants and exponents for onset mortality and onset slight lung
injury were amended by the Navy since Phase II to better account for
the best available science. Specifically, the equations were modified
in 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.
Comment 13: A commenter commented that the Navy only used the onset
mortality and onset slight lung injury criteria to determine the range
to effects, while it used the 50 percent mortality and 50 percent
slight lung injury criteria to estimate the numbers of marine mammal
takes. The commenter believes that this approach is inconsistent with
the manner in which the Navy estimated the numbers of takes for PTS,
TTS, and behavior for explosive activities. All of those takes have
been and continue to be based on onset, not 50-percent values. The
commenter commented on circumstances of the deaths of multiple common
dolphins during one of the Navy's underwater detonation events in March
2011 (Danil and St. Leger, 2011)
[[Page 66880]]
and indicated that the Navy's mitigation measures are not fully
effective, especially for explosive activities. The commenter believes
it would be more prudent for the Navy to estimate injuries and
mortalities based on onset rather than a 50-percent incidence of
occurrence. The Navy did indicate that it is reasonable to assume for
its impact analysis--thus its take estimation process--that extensive
lung hemorrhage is a level of injury that would result in mortality for
a wild animal (Department of the Navy 2017a). Thus, the commenter
comments that it is unclear why the Navy did not follow through with
that premise. The commenter recommends that NMFS use onset mortality,
onset slight lung injury, and onset GI tract injury thresholds to
estimate both the numbers of marine mammal takes and the respective
ranges to effect.
Response: Based on an extensive review of the incident referred to
by the commenter, in coordination with NMFS the Navy revised and
updated the mitigation for these types of events. There have been no
further incidents since these mitigation changes were instituted in
2011.
The Navy used the range to one percent risk of mortality and injury
(referred to as ``onset'' in the Draft EIS/OEIS) to inform the
development of mitigation zones for explosives. In all cases, the
mitigation zones for explosives extend beyond the range to one percent
risk of non-auditory injury, even for a small animal (representative
mass = 5 kg). In the FEIS/OEIS, the Navy has clarified that the
``onset'' non-auditory injury and mortality criteria are actually one
percent risk criteria.
Over-predicting impacts, which would occur with the use of one
percent non-auditory injury risk criteria in the quantitative analysis,
would not afford extra protection to any animal. The Navy, in
coordination with NMFS, has determined that the 50 percent incidence of
occurrence is a reasonable representation of a potential effect and
appropriate for take estimation.
Although the commenter implies that the Navy did not use extensive
lung hemorrhage as indicative of mortality, that statement is
incorrect. Extensive lung hemorrhage is assumed to result in mortality,
and the explosive mortality criteria are based on extensive lung injury
data See the 2017 technical report titled Criteria and Thresholds for
U.S. Navy Acoustic and Explosive Effects Analysis (Phase III).
Range to Effects
Comment 14: One commenter noted that regarding TTS, the ranges to
effect provided in Table 25 of the Federal Register notice of proposed
rulemaking and Table 6-4 of the LOA application appear to be incorrect.
The ranges for LF cetaceans should increase with increasing sonar
emission time. Therefore, the commenter recommended that NMFS determine
what the appropriate ranges to TTS for bin LF5 should be and amend the
ranges for the various functional hearing groups in the tables
accordingly.
Response: The error in the table has been fixed; specifically, the
ranges for MF cetaceans have been revised. Note that the distances are
shorter than initially provided in the proposed rule, indicating that
the impacts of exposure to this bin are fewer than initially implied by
the table. Regardless, the error was only associated with the
information presented in this table; there was no associated error in
any distances used in the take estimation, and both the take estimates
and our findings remain the same.
Mitigation and Avoidance Calculations
Comment 15: Commenters cited concerns that there was not enough
information by which to evaluate the Navy's post-modeling calculations
to account for mitigation and avoidance and imply that Level A takes
and mortality takes may be underestimated. A commenter recommended that
NMFS (1) authorize 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 and (2) use
those numbers, in addition to the revised Level B harassment takes, to
inform its negligible impact determination analyses.
Response: The consideration of marine mammal avoidance and
mitigation effectiveness is integral to 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; additional
information on the mitigation analysis also has been included in the
final rule.
Sound levels diminish quickly below levels that could cause PTS.
Studies have shown that all animals observed avoid areas well beyond
these zones; therefore, the vast majority of animals are likely to
avoid sound levels that could cause injury to their ear. As discussed
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, animats in the Navy's acoustic effects
model do not move horizontally or ``react'' to sound in any way. The
current best available science based on a growing body of behavioral
response research shows that 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.
Specifically, behavioral response literature, including the recent
3S and SOCAL BRS studies, indicate that the 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. 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.
As discussed 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, 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 Level A take 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.
[[Page 66881]]
Last, 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 very clearly explains in
detail how species sightability, the Lookout's ability to observe the
range to PTS (for sonar and other transducers) and mortality (for
explosives), 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 the ability for
sound sources to be positively controlled (powered down) are considered
in the post-modeling calculation to account for mitigation and
avoidance. It is not necessary to view the many tables of numbers
generated in the assessment to evaluate the method.
Comment 16: A commenter stated in regards to the method in which
the Navy's post-model calculation considers avoidance specifically
(i.e., assuming animals present beyond the range of PTS for the first
few pings will be able to avoid it and incur only TTS, which results in
a 95 percent reduction in the number of estimated PTS takes predicted
by the model), given that sound sources are moving, it may not be until
later in an exercise that the animal is close enough to experience PTS,
and it is those few close pings that contribute to the potential to
experience PTS. An animal being beyond the PTS zone initially has no
bearing on whether it will come within close range later during an
exercise since both sources and animals are moving. In addition, Navy
vessels may move faster than the ability of the animals to evacuate the
area. The Navy should have been able to query the dosimeters of the
animats to verify whether its 5-percent assumption was valid.
Commenters are concerned that this method underestimates the number of
PTS takes.
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. 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.'' In regard to the
comment about vessels moving faster than animals' ability to get out of
the way, as discussed in the Navy's 2018 technical report titled
Quantitative Analysis for Estimating Acoustic and Explosive Impacts to
Marine Mammals and Sea Turtles, 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. Querying the dosimeters of the
animats would not produce useful information since, as discussed
previously, the animats do not move in the horizontal and are not
programmed to ``react'' to sound or any other stimulus. The commenter
references comments that they have previously submitted on the Navy's
Gulf of Alaska incidental take regulations and we refer the commenter
to NMFS' responses, which were included in the Federal Register
document announcing the issuance of the final regulations (82 FR 19572,
April 27, 2017).
Underestimated Beaked Whale Injury and Mortality
Comment 17: A commenter commented that the Navy and NMFS both
underestimate take for Cuvier's beaked whales because they are
extremely sensitive to sonar. A new study of Cuvier's beaked whales in
Southern California exposed to mid and high-power sonar confirmed that
they modify their diving behavior up to 100-km away (Falcone et al.,
2017). The commenter asserted that this science disproves NMFS'
assumption that beaked whales will find suitable habitat nearby within
their small range. This modified diving behavior, which was
particularly strong when exposed to mid-power sonar, indicates
disruption of feeding. Accordingly, impacts on Cuvier's beaked whales
could include interference with essential behaviors that will have more
than a negligible impact on this species. In addition, Lookouts and
shutdowns do not protect Cuvier's beaked whales from Navy sonar because
this is a deep-diving species that is difficult to see from ships.
Response: Takes of Cuvier's beaked whales are not underestimated.
The behavioral harassment threshold for beaked whales has two
components, both of which consider the sensitivity of beaked whales.
First, the biphasic behavioral harassment function for beaked whales,
which is based on data on beaked whale responses, has a significantly
lower mid-point than other groups and also reflects a significantly
higher probability of ``take'' at lower levels (e.g., close to 15
percent at 120 dB). Additionally, the distance cut-off used for beaked
whales is farther than for any other group (50 km, for both the MF1 and
MF4 bins, acknowledging the fact that the unpredictability of dipping
sonar likely results in takes at greater distances than other more
predictable sources of similar levels). Regarding the referenced
article, the commenter is selectively citing only part of it. The
study, which compiles information from multiple studies, found that
shallow dives were predicted to increase in duration as the distance to
both high-and mid-power MFAS sources decreased, beginning at
approximately 100 km away and, specifically, the differences only
varied from approximately 20 minutes without MFAS to about 24 minutes
with MFAS at the closest distance (i.e., the dive time varied from 20
to 24 minutes over the distance of 100 km away to the closest distance
measured). Further, the same article predicted that deep dive duration
(which is more directly associated with feeding and linked to potential
energetic effects) was predicted to increase with proximity to mid-
power MFAS from approximately 60 minutes to approximately 90 minutes
beginning at around 40 km (10 dives). There were four deep dives
exposed high-power MFAS within 20 km, the distance at which deep dive
durations increased with the lower power source types. Other responses
to MFAS included deep dives that were shorter than typical and
shallower, and instances where there were no observed responses at
closer distances. The threshold for Level B harassment is higher than
just ``any measurable response'' and NMFS and the Navy worked closely
together to identify behavioral response functions and distance cut-
offs that reflect the best available science to identify when
[[Page 66882]]
marine mammal behavioral patterns will be disrupted to a point where
they are abandoned or significantly altered. Further, the take estimate
is in no way based on an assumption that beaked whales will always be
sighted by Lookouts--and adjustment to account for Lookout
effectiveness considers the variable detectability of different stocks.
In this rule, both the take estimate and the negligible impact analysis
appropriately consider the sensitivity of, and scale of impacts to (we
address impacts to feeding and energetics), Cuvier's (and all) beaked
whales.
Comment 18: A commenter commented that NMFS is underestimating
serious injury and mortality for beaked whales. A commenter noted the
statement in the proposed rule that because a causal relationship
between Navy MFAS use and beaked whale strandings has not been
established in all instances, and that, in some cases, sonar was
considered to be only one of several factors that, in aggregate, may
have contributed to the stranding event, NMFS does ``not expect
strandings, serious injury, or mortality of beaked whales to occur as a
result of training activities.'' (83 FR at 30007). The commenter
asserted that this opinion is inconsistent with best available science
and does not take into account the fact that the leading explanation
for the mechanism of sonar-related injuries--that whales suffer from
bubble growth in organs that is similar to decompression sickness, or
``the bends'' in human divers--has now been supported by numerous
papers. At the same time, the commenter argued that NMFS fails to
seriously acknowledge that sonar can seriously injure or kill marine
mammals at distances well beyond those established for permanent
hearing loss (83 FR 29916) and dismisses the risk of stranding and
other mortality events (83 FR 30007) based on the argument that such
effects can transpire only under the same set of circumstances that
occurred during known sonar-related events--an assumption that is
arbitrary and capricious. In conclusion, a commenter argued that none
of NMFS' assumptions regarding the expected lack of serious injury and
mortality for beaked whales are supported by the record, and all lead
to an underestimation of impacts.
Response: A commenter's characterization of NMFS' analysis is
incorrect. NMFS does not disregard the fact that it is possible for
naval activities using hull-mounted tactical sonar to contribute to the
death of marine mammals in certain circumstances (that are not present
in the HSTT Study Area) via strandings resulting from behaviorally
mediated physiological impacts or other gas-related injuries. 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 strandings in the
proposed rule. As noted, 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 HSTT Study Area and during the
specified activities (and which the Navy takes care across the world
not to operate under without additional monitoring). There have been no
documented beaked whale mortalities from Navy activities within the
HSTT Study Area. Further, none of the beaked whale strandings causally
associated with Navy sonar stranding are in the Pacific. For these
reasons, NMFS does not anticipate that the Navy's HSTT training or
testing activities will result in beaked whale marine mammal
strandings, and none are authorized. Furthermore, ongoing Navy funded
beaked whale monitoring at a heavily used training and testing area in
SOCAL has not documented mortality or habitat abandonment by beaked
whales. Passive acoustic detections of beaked whales have not
significantly changed over eight years of monitoring (DiMarzio et al.,
2018). From visual surveys in the area since 2006 there have been
repeated sightings of: the same individual beaked whale, beaked whale
mother-calf pairs, and beaked whale mother-calf pairs with mothers on
their second calf (Schorr et al., 2018). Satellite tracking studies of
beaked whale documented high site fidelity to this area even though the
study area is located in one of the most used Navy areas in the Pacific
(Schorr et al., 2018).
Ship Strike
Comment 19: A commenter commented that the Navy's current approach
to determine the risk of a direct vessel collision with marine mammals
is flawed and fails to account for the likelihood that ship strikes
since 2009 were unintentionally underreported. The commenters noted
that vessel collisions are generally underreported in part because they
can be difficult to detect, especially for large vessels and that the
distribution, being based on reported strikes, does not account for
this problem. Additionally, the commenter asserted that the Navy's
analysis does not address the potential for increased strike risk of
non-Navy vessels as a consequence of acoustic disturbance. For example,
some types of anthropogenic noise have been shown to induce near-
surfacing behavior in right whales, increasing the risk of ship-
strike--by not only the source vessel but potentially by third-party
vessels in the area--at relatively moderate levels of exposure (Nowacek
et al., 2004). An analysis based on reported strikes by Navy vessels
per se does not account for this additional risk. In assessing ship-
strike risk, the Navy should include offsets to account for potentially
undetected and unreported collisions.
Response: While NMFS agrees that broadly speaking the number of
total ship strikes may be underestimated due to incomplete information
from other sectors (shipping, etc.), NMFS is confident that whales
struck by Navy vessels are detected and reported, and Navy strikes are
the numbers used in NMFS' analysis to support the authorized number of
strikes. Navy ships have multiple Lookouts, including on the forward
part of the ship that can visually detect a hit whale (which has
occasionally occurred), in the unlikely event ship personnel do not
feel the strike. The 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.
Accordingly, NMFS is confident that the information used to support the
analysis is accurate and complete.
There is no evidence that Navy training and testing activities (or
other acoustic activities) increase the risk of nearby non-Navy vessels
(or other nearby Navy vessels not involved in the referenced training
or testing) striking marine mammals. More whales are struck by non-Navy
vessels off California in areas outside of the HSTT Study Area such as
approaches to Los Angeles and San Francisco.
Mitigation and Monitoring
Least Practicable Adverse Impact Determination
Comment 20: A commenter commented that deaths of, or serious
injuries to marine mammals that occur pursuant to activities conducted
under an incidental take authorization, while
[[Page 66883]]
perhaps negligible to the overall health and productivity of the
species or stock and of little consequence at that level, nevertheless
are clearly adverse to the individuals involved and results in some
quantifiable (though negligible) adverse impact on the population; it
reduces the population to some degree. Under the least practicable
adverse impact requirement, and more generally under the purposes and
policies of the MMPA, the commenter asserted that Congress embraced a
policy to minimize, whenever practicable, the risk of killing or
seriously injuring a marine mammal incidental to an activity subject to
section 101(a)(5)(A), including providing measures in an authorization
to eliminate or reduce the likelihood of lethal taking. The commenter
recommended that NMFS address this point explicitly in its analysis and
clarify whether it agrees that the incidental serious injury or death
of a marine mammal always should be considered an adverse impact for
purposes of applying the least practicable adverse impact standard.
Response: NMFS disagrees that it is necessary or helpful to
explicitly address the point the commenter raises in the general
description of the least practicable adverse impact standard. The
discussion of this standard already notes that there can be population-
level impacts that fall below the ``negligible'' standard, but that are
still appropriate to mitigate under the least practicable adverse
impact standard. It is always NMFS' practice to mitigate mortality to
the greatest degree possible, as death is the impact that is most
easily linked to reducing the probability of adverse impacts to
populations. However, we cannot agree that one mortality will always
decrease any population in a quantifiable or meaningful way. For
example, for very large populations, one mortality may fall well within
typical known annual variation and not have any effect on population
rates. Further, we do not understand the problem that the commenter's
recommendation is attempting to fix. Applicants generally do not
express reluctance to mitigate mortality, and we believe that
modifications of this nature would confuse the issue.
Comment 21: A commenter recommended that NMFS address the habitat
component of the least practicable adverse impact provision in greater
detail. It asserted that NMFS' discussion of critical habitat, marine
sanctuaries, and BIAs in the proposed rule is not integrated with the
discussion of the least practicable adverse impact standard. It would
seem that, under the least practicable adverse impact provision,
adverse impacts on important habitat should be avoided whenever
practicable. Therefore, to the extent that activities would be allowed
to proceed in these areas, NMFS should explain why it is not
practicable to constrain them further.
Response: 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 identified 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., calving areas in Hawaii, feeding areas
SOCAL). In addition to being delineated based on physical features that
drive habitat function (e.g., bathymetric features, among others for
some BIAs), the high densities and concentration of certain important
behaviors (e.g., feeding) 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.
Comment 22: 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. In this regard, the commenter
asserted that it seems as though the proposed ``effectiveness''
criterion more appropriately fits as an element of practicability and
should be addressed under that prong of the analysis. In other words, a
measure not expected to be effective should not be considered a
practicable means of reducing impacts.
Response: In the Mitigation Measures section, NMFS has explained in
detail our interpretation of the least practicable adverse impact
standard, the rationale for our interpretation, and our approach for
implementing our interpretation. The ability of a measure to reduce
effects on marine mammals is entirely related to its ``effectiveness''
as a measure, whereas the effectiveness of a measure is not connected
to its practicability. The commenter provides no support for its
argument, and NMFS has not implemented the Commission's suggestion.
Comment 23: A commenter recommended that NMFS recast its
conclusions to provide sufficient detail as to why additional measures
either are not needed (i.e., there are no remaining adverse impacts) or
would not be practicable to implement. The commenter states that the
most concerning element of NMFS' implementation of the least
practicable adverse impact standard is its suggestion that the
mitigation measures proposed by the Navy will ``sufficiently reduce
impacts on the affected mammal species and stocks and their habitats''
(83 FR 11045). That phrase suggests that NMFS is applying a ``good-
enough'' standard to the Navy's activities. Under the statutory
criteria, however, those proposed measures are ``sufficient'' only if
they have either (1) eliminated all adverse impacts on marine mammal
species and stocks and their habitat or (2) if adverse impacts remain,
it is impracticable to reduce them further.
Response: The statement that the commenter references does not
indicate that NMFS applies a ``good-enough'' standard to determining
least practicable adverse impact. Rather, it indicates that the
mitigation measures are sufficient to meet the statutory legal
standard. In addition, as NMFS has explained in our description of the
least practicable adverse impact standard, NMFS does not view the
necessary analysis through the yes/no lens that the commenter seeks to
prescribe. Rather, NMFS' least practicable adverse impact analysis
considers both the reduction of adverse effects and their
practicability. Further, since the proposed rule was published, the
Navy and NMFS have evaluated additional measures in the context of both
their practicability and their ability to further reduce impacts to
marine mammals and have determined that the addition of several
measures (see Mitigation Measures) is appropriate. Regardless, beyond
these new additional measures, where the Navy's HSTT activities are
concerned, the Navy has indicated that further procedural or area
mitigation of any kind (beyond that prescribed in this final rule)
would be entirely impracticable. NMFS has reviewed documentation and
analysis provided by the Navy explaining how and why specific
procedural and geographic based mitigation measures impact
practicability, and NMFS concurs with these assessments and has
determined that the mitigation measures outlined in the final rule
satisfy the statutory standard and that any adverse
[[Page 66884]]
impacts that remain are unable to be further mitigated.
Comment 24: A commenter recommended that any ``formal
interpretation'' of the least practicable adverse impact standard by
NMFS be issued in a stand-alone, generally applicable rulemaking (e.g.,
in amendments to 50 CFR 216.103 or 216.105) or in a separate policy
directive, rather than in the preambles to individual proposed rules.
Response: We appreciate the commenter's recommendation and may
consider the recommended approaches in the future. We note, however,
that providing relevant explanations in a proposed incidental take rule
is an effective and efficient way to provide information to the reader
and solicit focused input from the public, and ultimately affords the
same opportunities for public comment as a stand-alone rulemaking
would. NMFS has provided similar explanations of the least practicable
adverse impact standard in other recent section 101(a)(5)(A) rules,
including: U.S. Navy Operations of Surveillance Towed Array Sensor
System Low Frequency Active (SURTASS LFA) Sonar; Geophysical Surveys
Related to Oil and Gas Activities in the Gulf of Mexico; and the final
rule for U.S. Navy Training and Testing Activities in the Atlantic
Fleet Study Area.
Comment 25: A commenter cited two judicial decisions and commented
that the ``least practicable adverse impact'' standard has not been
met. A 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. A 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. A commenter argues 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: it
``cannot just parrot what the Navy says.''
Response: NMFS disagrees with much of what a commenter asserts.
When a suggested or recommended mitigation measure is impracticable,
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 this rule. First, the type of mitigation required varies 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. Examples of NMFS' analysis on this issue appear throughout the
rule. For instance, while it was not practicable for the Navy to
include a mitigation area for the Tanner-Cortes blue whale BIA, the
Navy did agree to expand mitigation protection to all of the other blue
whale BIAs in the SOCAL region. Additionally, while the Navy cannot
alleviate all training in the mitigation areas that protect small
resident odontocete populations in Hawaii, has further expanded the
protections in those areas such that it does not use explosives or MFAS
in the areas (MF1 bin in both areas, MF4 bin in the Hawaii Island
area). Nonetheless, NMFS agrees 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, and concur with
those aspects of the Navy's analysis with which NMFS agrees. A
commenter seems 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 HSTT Study Area. Discussion regarding specific
recommendations for mitigation measures provided by a commenter on the
proposed rule are discussed separately.
Procedural Mitigation Effectiveness and Recommendations
Comment 26: A commenter commented that the Navy's proposed
mitigation zones are similar to the zones previously used during Phase
II activities and are intended, based on the Phase III HSTT DEIS/OEIS,
to avoid the potential for marine mammals to be exposed to levels of
sound that could result in injury (i.e., PTS). However, the commenter
believed that Phase III proposed mitigation zones would not protect
various functional hearing groups from PTS. For example, the mitigation
zone for an explosive sonobuoy is 549 m but the mean PTS zones range
from 2,113-3,682 m for HF. Similarly, the mitigation zone for an
explosive torpedo is 1,920 m but the mean PTS zones range from 7,635-
10,062 m for HF, 1,969-4,315 m for LF, and 3,053-3,311 for PW. The
appropriateness of such zones is further complicated by platforms
firing munitions (e.g., for missiles and rockets) at targets that are
28 to 139 km away from the firing platform. An aircraft would clear the
target area well before it positions itself at the launch location and
launches the missile or rocket. Ships, on the other hand, do not clear
the target area before launching the missile or rocket. In either case,
marine mammals could be present in the target area unbeknownst to the
Navy at the time of the launch.
Response: NMFS is aware that some mitigation zones do not fully
cover the area in which an animal from a certain hearing group may
incur PTS. For this small subset of circumstances, NMFS discussed
potential enlargement of the mitigation zones with the Navy, but
concurred with the Navy's assessment that further enlargement would be
impracticable. Specifically, the Navy explained that explosive
mitigation zones, as discussed in Chapter 5 (Mitigation) of the HSTT
FEIS/OEIS, any additional increases in mitigation zone size (beyond
what is depicted for each explosive activity), or additional
observation requirements would be impracticable to implement due to
implications for safety, sustainability, the Navy's ability to meet
Title 10 requirements to successfully accomplish military readiness
objectives, and the Navy's ability to conduct testing associated with
required acquisition milestones or as required on an as-needed basis to
meet operational requirements. Additionally, Navy Senior Leadership has
approved and determined that the mitigation detailed in Chapter 5
(Mitigation) of the HSTT FEIS/OEIS provides the greatest extent of
protection that is practicable to implement. The absence of mitigation
to avoid all Level A harassment in some of these circumstances has been
analyzed, however, and the Navy is authorized for any of these Level A
harassment takes that may occur.
[[Page 66885]]
Comment 27: One commenter made several comments regarding visual
and acoustic detection as related to mitigating impacts that can cause
injury. The commenter noted that the Navy indicated in the HSTT DEIS/
OEIS that Lookouts would not be 100 percent effective at detecting all
species of marine mammals for every activity because of 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). The Navy has been collaborating with researchers
at the University of St. Andrews to study Navy Lookout effectiveness
and the commenter anticipates that the Lookout effectiveness study will
be very informative once completed, but notes that in the interim, the
preliminary data do provide an adequate basis for taking a
precautionary approach. The commenter believed that rather than simply
reducing the size of the mitigation zones it plans to monitor, the Navy
should supplement its visual monitoring efforts with other monitoring
measures including passive acoustic monitoring.
The commenter suggested that sonobuoys could be deployed with the
target in the various target areas prior to the activity. This approach
would allow the Navy to better determine whether the target area is
clear and remains clear until the munition is launched.
Although the Navy indicated that it was continuing to improve its
capabilities for using range instrumentation to aid in the passive
acoustic detection of marine mammals, it also stated that it didn't
have the capability or resources to monitor instrumented ranges in real
time for the purpose of mitigation. That capability clearly exists.
While available resources could be a limiting factor, the commenter
notes that personnel who monitor the hydrophones on the operational
side do have the ability to monitor for marine mammals as well. The
commenter has supported the use of the instrumented ranges to fulfill
mitigation implementation for quite some time (see the commenter's most
recent November 13, 2017 letter) and contends that localizing certain
species (or genera) provides more effective mitigation than localizing
none at all.
The commenter recommended that NMFS require the Navy to use passive
and active acoustic monitoring, whenever practicable, to supplement
visual monitoring during the implementation of its mitigation measures
for all activities that have the potential to cause injury or mortality
beyond those explosive activities for which passive acoustic monitoring
already was proposed, including those activities that would occur on
the SCORE and PMRF ranges.
Response: For explosive mitigation zones, any additional increases
in mitigation zone size (beyond what is depicted for each explosive
activity) or observation requirements would be impracticable to
implement due to implications for safety, sustainability, and the
Navy's ability to meet Title 10 requirements to successfully accomplish
military readiness objectives. We do note, however, that since the
proposed rule, the Navy has committed to implementing pre-event
observations for all in-water explosives events (including some that
were not previously monitored) and to using additional platforms if
available in the vicinity of the detonation area to help with this
monitoring.
As discussed in the comment, 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). For other explosive events, there are no platforms
participating that have passive acoustic monitoring capabilities.
Adding a passive acoustic monitoring capability (either by adding a
passive acoustic monitoring device 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 HSTT FEIS/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. Additionally, diverting platforms that have passive
acoustic monitoring platforms 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 realtime mitigation,
the commenter is correct that the Navy 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. However, as discussed above, 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. A more detailed
discussion of the limitations for on range passive acoustic detection
as real-time mitigation is provided in Comment 34 and is impracticable
for the Navy. The Navy's instrumented ranges were not developed for the
purpose of mitigation. For example, beaked whales produce highly
directed echolocation clicks that are difficult to simultaneously
detect on multiple hydrophones within the instrumented range at PMRF;
therefore, there is a high probability that a vocalizing animal would
be assigned a false location on the range (i.e., the Navy would not be
able to verify its presence in a mitigation zone). 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 would not be 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 HSTT FEIS/OEIS.
Comment 28: The commenter recommended that NMFS require the Navy to
conduct additional pre-activity overflights before conducting any
activities involving detonations barring any safety issues (e.g., low
fuel), as well as post-activity monitoring for activities involving
medium- and large caliber projectiles, missiles, rockets, and bombs.
Response: The Navy has agreed to implement pre-event observation
mitigation, as well as post-event observation, for all in-water
explosive event mitigation measures. 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.
Comment 29: One commenter recommended that the Navy implement
larger shutdown zones.
Response: The Navy mitigation zones represent the maximum surface
area the Navy can effectively observe based on the platform involved,
number of personnel that will be involved, and the number and type of
assets and resources available. As mitigation zone sizes increase, the
potential for observing marine mammals and thus reducing impacts
decreases, because the number of observers can't increase although the
area to observe increases. For instance, if a mitigation zone increases
from 1,000 to 2,000 yd., the area that must be observed increases five-
fold. NMFS has
[[Page 66886]]
analyzed the Navy's required mitigation and found that it will effect
the least practicable adverse impact. The Navy's mitigation measures
consider both the need to reduce potential impacts and the ability to
provide effective observations throughout a given mitigation zone. To
implement these mitigation zones, Navy Lookouts are trained to use a
combination of unaided eye and optics as they search the surface around
a vessel. In addition, there are other Navy personnel on a given bridge
watch (in addition to designated Lookouts), who are also constantly
watching the water for safety of navigation and marine mammals. Takes
that cannot be mitigated are analyzed and authorized provided the
necessary findings can be made.
Comment 30: Commenters commented that NMFS should cap the maximum
level of activities each year.
Response: The commenters offers no rationale for why a cap is
needed and nor do they suggest what an appropriate cap might be. The
Navy is responsible under Title 10 for conducting the needed amount of
testing and training to maintain military readiness, which is what they
have proposed and NMFS has analyzed. Further, the MMPA states that NMFS
shall issue MMPA authorizations if the necessary findings can be made,
as they have been here. Importantly, as described in the Mitigation
Areas section, the Navy will limit activities (active sonar, explosive
use, MTE exercises, etc.) to varying degrees in multiple areas that are
important to sensitive species or for critical behaviors in order to
minimize impacts that are more likely to lead to adverse effects on
rates of recruitment or survival.
Comment 31: A commenter suggested the Navy could improve observer
effectiveness through the use of NMFS-certified marine mammal
observers.
Response: The Navy currently requires at least one qualified
Lookout on watch at all times a vessel is underway. In addition, on
surface ships with hull-mounted sonars during sonar events, the number
increases with two additional Lookouts on the forward portion of the
vessel (i.e., total of three Lookouts). Furthermore, unlike civilian
commercial ships, there are additional bridge watch standers on Navy
ships viewing the water during all activities. The Navy's Marine
Species Awareness training that all bridge watchstanders including
Lookouts take has been reviewed and approved by NMFS. This training is
conducted annually and prior to MTEs. Note, Navy visual monitoring from
Lookouts and bridge watchstanders as well as unit-based passive
acoustic detection is used when available and appropriate.
As we understand from the Navy, mandating NMFS-certified marine
mammal observers on all ships would require setting up and
administering a certification program, providing security clearance for
certified people, ensuring that all platforms are furnished with these
individuals, and housing these people on ships for extended times from
weeks to months. This would be an extreme logistic burden on realistic
training. The requirement for additional non-Navy observers would
provide little additional benefit, especially at the near ship
mitigation ranges for mid-frequency active sonars on surface ships
(<1,000 yds), nor be significantly better than the current system
developed by the Navy in consultation with NMFS.
The purpose of Navy Lookouts is to provide sighting information for
other boats and vessels in the area, in-water debris, and other safety
of navigation functions. During active sonar use, additional personnel
are assigned for the duration of the sonar event. In addition, the
other Navy personnel on a given bridge watch along with designated
Lookouts are also constantly watching the water for safety of
navigation and marine mammals.
Navy training and testing activities often occur simultaneously and
in various regions throughout the HSTT Study Area, with underway time
that could last for days or multiple weeks at a time. The pool of
certified marine mammal observers across the U.S. West Coast is rather
limited, with many already engaged in regional NMFS survey efforts.
Relative to the number of dedicated MMOs that would be required to
implement this condition, as of July 2018, there are approximately 22
sonar-equipped Navy ships (i.e., surface ships with hull-mounted active
sonars) stationed in San Diego. Six additional vessels from the Pacific
Northwest also transit to Southern California for training (28 ships
times 2 observers per watch times 2 watches per day = minimum of 112
observers).
Senior Navy commands in the Pacific continuously reemphasize the
importance of Lookout responsibilities to all ships. Further, the Navy
has an ongoing study in which certified Navy civilian scientist
observers embark periodically on Navy ships in support of a comparative
Lookout effectiveness study. Results from this study will be used to
make recommendations for further improvements to Lookout training.
Additionally, we note that the necessity to include trained NMFS-
approved PSOs on Navy vessels, while adding little or no additional
protective or data-gathering value, would be very expensive and those
costs would need to be offset--most likely through reductions in the
budget for Navy monitoring, through which invaluable data is gathered.
Comment 32: Commenters commented that NMFS should consider
increasing the exclusion zone to the 120 dB isopleth because some
animals are sensitive to sonar at low levels of exposure.
Response: First, it is important to note that the Commenters are
suggesting that NMFS require mitigation that would eliminate all take,
which is not what the applicable standard requires. Rather, NMFS is
required to put in place measures that effect the ``least practicable
adverse impact.'' Separately, NMFS acknowledges that some marine
mammals may respond to sound at 120 dB in some circumstances; however,
based on the best available data, only a subset of those exposed at
that low level respond in a manner that would be considered harassment
under the MMPA. NMFS and the Navy have quantified those individuals of
certain stocks where appropriate, analyzed the impacts, and authorized
them where needed. Further, NMFS and the Navy have identified exclusion
zone sizes that are best suited to minimize impacts to marine mammal
species and stocks and their habitat while also being practicable (see
Mitigation section).
Comment 33: A commenter commented that NMFS should impose a 10-kn
ship speed in biologically important areas and critical habitat for
marine mammals to reduce vessel strikes. One commenter also
specifically referenced this measure in regard to humpback whales and
blue whales.
Response: This issue also is addressed elsewhere in the Comments
and Responses section for specific mitigation areas. However, 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 Navy ships at higher speeds and
the presence of effective Lookouts, any further reduction in speed
would reduce the already low probability of ship strike little, if any.
The Navy is unable to impose a 10-kn ship speed limit because it would
not be practical to implement and would impact the effectiveness of
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
[[Page 66887]]
typically use the lowest speed practical given individual mission
needs. NMFS has reviewed the Navy's analysis of these additional
restrictions and the impacts they would have on military readiness and
concurs with the Navy's assessment that they are impracticable.
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 Southern California, with no whales
struck by the Navy from 2010-2018. Current Navy Standard Operating
Procedures and mitigations require a minimum of at least one Lookout on
duty while underway (in addition to bridge watch personnel) and, so
long as safety of navigation is maintained, to keep 500 yards away from
large whales and 200 yards away from other marine mammals (except for
bow-riding dolphins and pinnipeds hauled out on shore or structures).
Furthermore, there is no Navy ship strike of a marine mammal on record
in SOCAL that has occurred in the coastal area (~40 Nmi from shore),
which is where speed restrictions are most requested. Finally, the most
recent model estimate of the potential for civilian ship strike risk to
blue, humpback, and fin whales off the coast of California found the
highest risk near San Francisco and Long Beach associated with
commercial ship routes to and from those ports (Rockwood et al., 2018).
There was no indication of a similar high risk to these species off San
Diego, where the HSTT Study Area occurs.
Previously, the Navy commissioned a vessel density and speed report
based on an analysis of Navy ship traffic in the HSTT Study Area
between 2011 and 2015. Median speed of all Navy vessels within the HSTT
Study Area is typically already low, with median speeds between 5 and
12 knots. Further, the presence and transits of commercial and
recreational vessels, annually numbering in the thousands, poses a more
significant risk to large whales than the presence of Navy vessels. The
HSTT FEIS/OEIS Chapter 3 (Affected Environment and Environmental
Consequences) Section 3.7.3.4.1 (Impacts from Vessels and In-Water
Devices) and Appendix K, Section K.4.1.6.2 (San Diego (Arc) Blue Whale
Feeding Area Mitigation Considerations), explain the important
differences between most Navy vessels and their operation and
commercial ships that make Navy vessels much less likely to strike a
whale.
When developing Phase III mitigation measures, the Navy analyzed
the potential for implementing additional types of mitigation, such as
vessel speed restrictions within the HSTT Study Area. The Navy
determined that based on how the training and testing activities will
be conducted within the HSTT 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 HSTT
FEIS/OEIS.
Comment 34: Commenters commented that NMFS should improve detection
of marine mammals with restrictions on low-visibility activities and
alternative detection such as thermal or acoustic methods.
Response: The Navy has compiled information related to the
effectiveness of certain equipment to detect marine mammals in the
context of their activities, as well as the practicality and effect on
mission effectiveness of using various equipment. NMFS has reviewed
this evaluation and concurs with the characterization and the
conclusions below.
Low visibility--Anti-submarine warfare training involving the use
of mid-frequency active sonar typically involves the periodic use of
active sonar to develop the ``tactical picture,'' or an understanding
of the battle space (e.g., area searched or unsearched, presence of
false contacts, and an understanding of the water conditions).
Developing the tactical picture can take several hours or days, and
typically occurs over vast waters with varying environmental and
oceanographic conditions. Training during both high visibility (e.g.,
daylight, favorable weather conditions) and low visibility (e.g.,
nighttime, inclement weather conditions) is vital because sonar
operators must be able to understand the environmental differences
between day and night and varying weather conditions and how they
affect sound propagation and the detection capabilities of sonar.
Temperature layers move up and down in the water column and ambient
noise levels can vary significantly between night and day, affecting
sound propagation and how sonar systems are operated. Reducing or
securing power in low-visibility conditions as a mitigation would
affect a commander's ability to develop the tactical picture and would
prevent sonar operators from training in realistic conditions. Further,
during integrated training multiple vessels and aircraft may
participate in an exercise using different dimensions of warfare
simultaneously (e.g., submarine warfare, surface warfare, air warfare,
etc.). If one of these training elements were adversely impacted (e.g.,
if sonar training reflecting military operations were not possible),
the training value of other integrated elements would also be degraded.
Additionally, failure to test such systems in realistic military
operational scenarios increases the likelihood these systems could fail
during military operations, thus unacceptably placing Sailors' lives
and the Nation's security at risk. Some systems have a nighttime
testing requirement; therefore, these tests cannot occur only in
daylight hours. Reducing or securing power in low visibility conditions
would decrease the Navy's ability to determine whether systems are
operationally effective, suitable, survivable, and safe for their
intended use by the fleet even in reduced visibility or difficult
weather conditions.
Thermal detection--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. 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. 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 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. 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
[[Page 66888]]
between a surfaced marine mammal (i.e., the body or blow of a whale)
and the environment (i.e., the water and air). Although thermal
detection may be reliable in some applications and environments, the
current technologies are limited by their: (1) Low sensor resolution
and a narrow fields of view, (2) reduced performance in certain
environmental conditions, (3) inability to detect certain animal
characteristics and behaviors, and (4) high cost and uncertain long
term reliability.
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 such
as 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.
One example of trying to use existing DoD thermal system is being
proposed by the U.S. Air Force. The Air Force agreed to attempt to use
specialized U.S. Air Force aircraft with military thermal detection
systems for marine mammal detection and mitigation during a limited at-
sea testing event. It should be noted, however, these systems are
specifically designed for and integrated into a small number of U.S.
Air Force aircraft and cannot be added or effectively transferred
universally to Navy aircraft. The effectiveness remains unknown in
using a standard DoD thermal system 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 positive, etc.)
Finally, current DoD thermal sensors are not always optimized for
marine mammal detections verse 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 marine mammal detection
have not been sufficiently studied both in terms of their effectiveness
within the environmental conditions found in the HSTT Study Area and
their compatibility with Navy training and testing (i.e., polar waters
vs. temperate waters). 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 Study Area. Furthermore, thermal detection systems are
designed to detect marine mammals and do not have the capability to
detect other resources for which the Navy is required to implement
mitigation, including sea turtles. Focusing on thermal detection
systems could also provide a distraction from and compromise to the
Navy's ability to implement its established observation and mitigation
requirements. The mitigation measures discussed in Chapter 5
(Mitigation), Section 5.3 (Procedural Mitigation to be Implemented) of
the HSTT FEIS/OEIS 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.
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, follow-on efforts and testing are planned for 2018-2019. The
Office of Naval Research Marine Mammals and Biology program funded a
project (2013-2018) to test the thermal limits of infrared-based
automatic whale detection technology. This project is 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.
The Office of Naval Research Marine Mammals and Biology program is
currently funding an ongoing project (2013-2018) that is testing the
thermal limits of infrared based automatic whale detection technology
(Principal Investigators: Olaf Boebel and Daniel Zitterbart). This
project is focused on (1) capturing whale spouts at two different
locations featuring subtropical and tropical water temperatures; (2)
optimizing detector/classifier performance on the collected data; and
(3) testing system performance by comparing system detections with
concurrent visual observations. In addition, Defense Advanced Research
Projects Agency (DARPA) has funded six initial studies to test and
evaluate current technologies and algorithms to automatically detect
marine mammals (IR thermal detection being one of the technologies) on
an unmanned surface vehicle. Based on the outcome of these initial
studies, follow-on efforts and testing are planned for 2018-2019.
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
[[Page 66889]]
detection studies and any associated practicability assessments at the
annual adaptive management meetings.
Passive Acoustic Monitoring--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). For other explosive events, there are no platforms
participating that have passive acoustic monitoring capabilities.
Adding a passive acoustic monitoring capability (either by adding a
passive acoustic monitoring device 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 Chapter 5
(Mitigation), Section 5.5.3 (Active and Passive Acoustic Monitoring
Devices) of the HSTT FEIS/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. Additionally, diverting
platforms that have passive acoustic monitoring platforms would impact
their ability to meet their Title 10 requirements and reduce the
service life of those systems.
The use of real-time passive acoustic monitoring (PAM) for
mitigation at the Southern California Anti-submarine Warfare Range
(SOAR) exceeds the capability of current technology. The Navy has a
significant research investment in the Marine Mammal Monitoring on Navy
Ranges (M3R) system at three ocean locations including SOAR. However,
this system was designed and intended to support marine mammal research
for select species, and not as a mitigation tool. Marine mammal PAM
using instrumented hydrophones is still under development and while it
has produced meaningful results for marine species monitoring,
abundance estimation, and research, it was not developed for nor is it
appropriate for real-time mitigation. The ability to detect, classify,
and develop an estimated position (and the associated area of
uncertainty) differs across species, behavioral context, animal
location vs. receiver geometry, source level, etc. Based on current
capabilities, and given adequate time, vocalizing animals within an
indeterminate radius around a particular hydrophone are detected, but
obtaining an estimated position for all individual animals passing
through a predetermined area is not assured. Detecting vocalizations on
a hydrophone does not determine whether vocalizing individuals would be
within the established mitigation zone in the timeframes required for
mitigation. Since detection ranges are generally larger than current
mitigation zones for many activities, this would unnecessarily delay
events due to uncertainty in the animal's location and put at risk
event realism.
Furthermore, PAM at SOAR does not account for animals not
vocalizing. For instance, there have been many documented occurrences
during PAM verification testing at SOAR of small boats on the water
coming across marine mammals such as baleen whales that were not
vocalizing and therefore not detected by the range hydrophones. Animals
must vocalize to be detected by PAM; the lack of detections on a
hydrophone may give the false impression that the area is clear of
marine mammals. The lack of vocalization detections is not a direct
measure of the absence of marine mammals. If an event were to be moved
based upon low-confidence localizations, it may inadvertently be moved
to an area where non-vocalizing animals of undetermined species are
present.
To develop an estimated position for an individual, it must be
vocalizing and its vocalizations must be detected on at least three
hydrophones. The hydrophones must have the required bandwidth, and
dynamic range to capture the signal. In addition, calls must be
sufficiently loud so as to provide the required signal to noise ratio
on the surrounding hydrophones. Typically, small odontocetes echolocate
with a directed beam that makes detection of the call on multiple
hydrophones difficult. Developing an estimated position of selected
species requires the presence of whistles which may or may not be
produced depending on the behavioral state. Beaked whales at SOAR
vocalize only during deep foraging dives which occur at a rate of
approximately 10 per day. They produce highly directed echolocation
clicks that are difficult to simultaneously detect on multiple
hydrophones. Current real-time systems cannot follow individuals and at
best produce sparse positions with multiple false locations. The
position estimation process must occur in an area with hydrophones
spaced to allow the detection of the same echolocation click on at
least three hydrophones. Typically, a spacing of less than 4 km in
water depths of approximately 2 km is preferred. In the absence of
detection, the analyst can only determine with confidence if a group of
beaked whales is somewhere within 6 km of a hydrophone. Beaked whales
produce stereotypic click trains during deep (<500 m) foraging dives.
The presence of a vocalizing group can be readily detected by an
analyst by examining the click structure and repetition rate. However,
estimating position is possible only if the same train of clicks is
detected on multiple hydrophones which is often precluded by the
animal's narrow beam pattern. Currently, this is not an automated
routine.
In summary, the analytical and technical capabilities required to
use PAM such as M3R at SOAR as a required mitigation tool are not
sufficiently robust to rely upon due to limitations with near real-time
classification and determining estimated positions. The level of
uncertainty as to a species presence or absence and location are too
high to provide the accuracy required for real-time mitigation. As
discussed in Chapter 5 (Mitigation) of the HSTT FEIS/OEIS, existing
Navy visual mitigation procedures and measures, when performed by
individual units at-sea, still remain the most practical means of
protection for marine species.
Comment 35: Commenters commented that NMFS should add mitigation
for other marine mammal stressors such as dipping sonar, pile driving,
and multiple exposures near homeports.
Response: The Navy implements a 200-yd shutdown for dipping sonar
and a 100-yd exclusion zone for pile-driving. It is unclear what the
commenter means by adding mitigation for ``multiple exposures'' near
homeports, and therefore no explanation can be provided.
Mitigation Areas
Introduction
The Navy included a comprehensive proposal of mitigation measures
in their initial application that included procedural mitigations that
reduce the likelihood of mortality, injury, hearing impairment, and
more severe behavioral responses for most species. The Navy also
included time/area mitigation that further protects areas where
important behaviors are conducted and/or sensitive species congregate,
which reduces the likelihood of takes that are likely to impact
reproduction or survival (as described in the Mitigation Measures
section of the final rule and the Navy's application). 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
proposal
[[Page 66890]]
and 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 necessary for NMFS to consider whether there are additional
practicable measures that could also contribute to the reduction of
adverse effects on the species or stocks through effects on annual
rates of recruitment or survival. In the case of the Navy's HSTT
application, we worked with the Navy prior to the publication of the
proposed rule and ultimately the Navy agreed to increase geographic
mitigation areas adjacent to the island of Hawaii to more fully
encompass specific biologically important areas and the Alenuihaha
Channel and to limit additional anti-submarine warfare mid-frequency
active sonar (ASW) source bins (MF4) within some geographic mitigation
areas.
During the public comment period on the proposed rule, NMFS
received numerous recommendations for the Navy to implement additional
mitigation measures, both procedural and time/area limitations.
Extensive discussion of the recommended mitigation measures in the
context of the factors considered in the least practicable adverse
impact analysis (considered in the Mitigation Measures section of the
final rule and described below), as well as considerations of alternate
iterations or portions of the recommended measures considered to better
address practicability concerns, resulted in the addition of several
procedural mitigations and expansion of multiple time/area mitigations
(see the Mitigation Measures section in the final rule). These
additional areas reflect, for example, concerns about blue whales in
SOCAL and small resident odontocete populations in Hawaii (which
resulted in expanded time/area mitigation), focus on areas where
important behaviors and habitat are found (e.g., in BIAs), and
enhancement of the Navy's ability to detect and reduce injury and
mortality (which resulted in expanded monitoring before and after
explosive events). Through extensive discussion, NMFS and the Navy
worked to identify and prioritize additional mitigation measures that
are likely to reduce impacts on marine mammal species or stocks and
their habitat and are also possible for the Navy to implement.
Following the publication of the 2013 HSTT MMPA incidental take
rule, the Navy (and NMFS) were sued and the resulting settlement
agreement prohibited or restricted Navy activities within specific
areas in the HSTT Study Area. These provisional prohibitions and
restrictions on activities within the HSTT Study Area were derived
pursuant to negotiations with the plaintiffs in that lawsuit were
specifically not evaluated or selected based on the type of thorough
examination of best available science that occurs through the
rulemaking process under the MMPA, or through related analyses
conducted under the National Environmental Policy Act (NEPA) or the
ESA. The agreement did not constitute a concession by the Navy as to
the potential impacts of Navy activities on marine mammals or any other
marine species, or to the practicability of the measures. The Navy's
adoption of restrictions on its HSTT activities as part of a relatively
short-term settlement does not mean that those restrictions are
necessarily supported by the best available science, likely to reduce
impacts to marine mammals species or stocks and their habitat, or
practicable to implement from a military readiness standpoint over the
longer term in the HSTT Study Area. Accordingly, as required by
statute, NMFS analyzed the Navy's activities, impacts, mitigation and
potential mitigation (including the settlement agreement measures)
pursuant to the ``least practicable adverse impact'' standard to
determine the appropriate mitigation to include in these regulations.
Some of the measures included in the settlement agreement are included
in the final rule, while some are not. Other measures that were not
included in the settlement agreement are included in the final rule.
Ultimately, the Navy adopted all mitigation measures that are
practicable without jeopardizing its mission and Title 10
responsibilities. In other words, a comprehensive assessment by Navy
leadership of the final, entire list of mitigation measures concluded
that the inclusion of any further mitigation beyond those measures
identified here in the final rule would be entirely impracticable. NMFS
independently reviewed the Navy's practicability determinations for
specific mitigation areas and concurs with the Navy's analysis.
As we outlined in the Mitigation Measures section, NMFS has
reviewed Appendix K (Geographic Mitigation Assessment) in the Navy's
HSTT FEIS/OEIS and information contained reflects the best available
science as well as a robust evaluation of the practicability of
different measures, and NMFS uses Appendix K to support our independent
least practicable adverse impact analysis. Below is additional
discussion regarding specific recommendations for mitigation measures.
Comment 36: With respect to the national security exemption related
to mitigation areas, a commenter recommended that NMFS should specify
that authorization may be given only by high-level officers, consistent
with the Settlement Agreement or with previous HSTT rulings.
Response: The Navy provided the technical analyses contained in
Appendix K (Geographic Mitigation Assessment) of the HSTT FEIS/OEIS
that included details regarding changing the measure to the appropriate
delegated Command designee (see specifically Appendix K, Section
K.2.2.1 (Proposed Mitigation Areas within the HSTT Study Area), for
each of the proposed areas). The commenter proposed ``authorization may
be given only by high-level officers'' and therefore appears to have
missed the designations made within the cited sections above since
those do constitute positions that could only be considered ``high
level officers.'' The decision would be delegated to high-level
officers. This delegation has been clarified in the Final rule as
``permission from the appropriate designated Command authority.''
SOCAL Areas
Comment 37: NPS recommended that the Navy consider the following as
it plans to conduct activities in the HSTT Study Area. NPS noted the
units of the NPS system that occur near the Navy's training and testing
locations in Southern California and which may be affected by noise
including Channel Islands National Park (NP) and Cabrillo National
Monument.
Response: National Parks and marine protected areas in are
addressed in Chapter 6 of the HSTT FEIS/OEIS. The Channel Islands
National Marine Sanctuary consists of an area of 1,109 nmi\2\ around
Anacapa Island, Santa Cruz Island, Santa Rosa Island, San Miguel Island
and Santa Barbara Island to the south. Only 92 nmi\2\ of Santa Barbara
Island, or about 8 percent of the Channel Island National Marine
Sanctuary, occurs within the SOCAL portion of the HSTT Study Area, but
the entirety of that piece is included in the Santa Barbara Mitigation
Area. The Navy will continue to implement a mitigation area out to 6
nmi of Santa Barbara Island, which includes a portion of the Channel
Island National Marine Sanctuary and the Santa Barbara Marine Protected
Area where the Navy will restrict the use of MF1 sonar sources and some
explosive during training. Please refer to Figure 5.4-4 in the Navy's
HSTT FEIS/OEIS shows the
[[Page 66891]]
spatial extent of the Santa Barbara Island mitigation area.
Cabrillo National Monument only contains some intertidal areas, but
no marine waters. No Navy activities overlap with the Cabrillo National
Monument; therefore, no impacts are expected.
Comment 38: A commenter recommended to extend the seasonality of
the San Diego Arc Mitigation Area to December 31 for blue whales are
present off southern California almost year round, and relatively
higher levels from June 1 through December 31.
Response: Analysis of the San Diego Arc Mitigation Area and its
consideration for additional geographic mitigation is provided in the
HSTT FEIS/OEIS in Appendix K (Geographic Mitigation Assessment),
Section K.4.1.6 (San Diego (Arc) Blue Whale Feeding Area; Settlement
Areas 3-A through 3-C, California Coastal Commission 3 nmi Shore Area,
and San Diego Arc Area), Section K.5.5 (Settlement Areas within the
Southern California Portion of the HSTT Study Area), and Section K.6.2
(San Diego Arc: Area Parallel to the Coastline from the Gulf of
California Border to just North of Del Mar). This analysis included
consideration of seasonality and the potential effectiveness of
restrictions to use of mid-frequency active sonar by Navy in the area.
Based on the Appendix K (Geographic Mitigation Assessment) analyses,
the Navy will implement additional mitigation within the San Diego Arc
Mitigation Area, as detailed in Chapter 5 (Mitigation) Section 5.4.3
(Mitigation Areas for Marine Mammals in the Southern California Portion
of the Study Area) of the HSTT FEIS/OEIS, to further avoid or reduce
impacts on marine mammals from acoustic and explosive stressors and
vessel strikes from Navy training and testing in this location. Since
the proposed rule, the Navy is now limiting MF1 surface ship hull-
mounted MFAS even further in the San Diego Arc Mitigation Area. The
Navy will not conduct more than 200 hrs of MF1 MFAS in the combined
areas of the San Diego Arc Mitigation Area and newly added San Nicholas
Island and Santa Monica/Long Beach Mitigation Areas. As described in
the proposed rule, the Navy will not use explosives that could
potentially result in the take of marine mammals during large-caliber
gunnery, torpedo, bombing, and missile (including 2.75'' rockets)
activities during training and testing in the San Diego Mitigation
Area. Regarding the recommended increase in seasonality to December 31,
the San Diego Arc and current seasonality is based on the Biologically
Important Area associated with this mitigation area (Calambokidis et
al., 2017), which identifies the primary months for feeding. While blue
whale calls have been detected in Southern California through December
(Rice et al., 2017, Lewis and [Scaron]irovi[cacute], in press), given a
large propagation range (10-50 km or more) for low-frequency blue whale
vocalization, blue whale call detection from a Navy-funded single
passive acoustic device near the San Diego Arc may not be a direct
correlation with blue whale presence within the San Diego Arc from
November through December. In addition, passive acoustic call detection
data does not currently allow for direct abundance estimates. Calls may
indicate some level of blue whale presence, but not abundance or
individual residency time. In the most recent Navy-funded passive
acoustic monitoring report including the one site in the northern San
Diego Arc from June 2015 to April 2016, blue whale call detection
frequency near the San Diego Arc starts declining in November after an
October peak (Rice et al., 2017, [Scaron]irovi[cacute], personal
communication). The newest Navy-funded research on blue whale movements
from 2014 to 2017 along the U.S. West Coast based on satellite tagging,
has shown that individual blue whale movement is wide ranging with
large distances covered daily (Mate et al., 2017). Nineteen (19) blue
whales were tagged in 2016, the most recent reporting year available
(Mate et al., 2017). Only 5 of the 19 blue whales spent time in the
SOCAL portion of the HSTT Study Area, and only spent a few days within
the range complex (2-13 days). Average distance from shore for blue
whales was 113 km. None of the 19 blue whales tagged in 2016 spent time
within the San Diego Arc. From previous year efforts (2014-2015), only
a few tagged blue whales passed through the San Diego Arc. In addition,
Navy and non-Navy-funded blue whale satellite tagging studies started
in the early 1990s and has continued irregularly through 2017. In
general, most blue whales start a south-bound migration from the
``summer foraging areas'' in the mid- to late-fall time period, unless
food has not been plentiful, which can lead to a much earlier migration
south. Therefore, while blue whales have been documented within the San
Diego Arc previously, individual use of the area is variable, likely of
short duration, and declining after October. Considering the newest
passive acoustic and satellite tagging data, there is no scientific
justification for extending the San Diego Arc Mitigation Area period
from October 31 to December 31.
Comment 39: A commenter recommended limiting all MF1 use within the
San Diego Arc Mitigation Area. A commenter also recommended NMFS should
carefully consider prohibiting use of other LFAS and MFAS during the
time period the San Diego Arc Mitigation Areas is in place, and for the
MTEs to be planned for other months of the year.
Response: Since the proposed rule, the Navy is now limiting MF1
surface ship hull-mounted MFAS even further in the San Diego Arc
Mitigation Area. The Navy will not conduct more than 200 hrs of MF1
MFAS in the combined areas of the San Diego Arc Mitigation Area and
newly added San Nicholas Island and Santa Monica/Long Beach Mitigation
Areas. Appendix K (Geographic Mitigation Assessment) of the HSTT FEIS/
OEIS discusses the Navy's analysis of MFAS restrictions within the San
Diego Arc Mitigation Area. Other training MFAS systems are likely to be
used less frequently in the vicinity of the San Diego Arc area than
surface ship MFAS. Given water depths, the San Diego Arc area is not
conducive for large scale anti-submarine warfare exercises, nor near
areas where other anti-submarine warfare training and testing occurs.
Due to the presence of existing Navy subareas in the southern part of
the San Diego Arc, a limited amount of helicopter dipping MFAS could
occur. These designated range areas are required for proximity to
airfields in San Diego such as Naval Air Station North Island and for
airspace management. However, helicopters only used these areas in the
Arc for a Kilo Dip. A Kilo Dip is a functional check of approximately
1-2 pings of active sonar to confirm the system is operational before
the helicopter heads to more remote offshore training areas. This
ensures proper system operation and avoids loss of limited training
time, expenditure of fuel, and cumulative engine use in the event of
equipment malfunction. The potential effects of dipping sonar have been
accounted for in the Navy's analysis. Dipping sonar is further
discussed below in Comment 40.
Comment 40: A commenter recommended prohibiting the use of air-
deployed mid-frequency active sonar in the San Diego Arc Mitigation
Area.
Response: The HSTT FEIS/OEIS and specifically Appendix K
(Geographic Mitigation Assessment) discuss the Navy's analysis of mid-
frequency and low-frequency active sonar restrictions within the San
Diego Arc. Other sonar systems are likely to be used less frequently in
the vicinity of the San
[[Page 66892]]
Diego Arc than surface ship mid-frequency active sonars. In regard to
the recommendation to prohibit ``air-deployed'' or dipping mid-
frequency active sonar, the only helicopter dipping sonar activity that
would likely be conducted in the San Diego Arc area is a Kilo Dip,
which occurs relatively infrequently and involves a functional check of
approximately 1-2 pings of active sonar before moving offshore beyond
the San Diego Arc to conduct the training activity. During use of this
sonar, the Navy will implement the procedural mitigation as described
in Section 5.3.2.1 (Active Sonar). The Kilo Dip functional check needs
to occur close to Naval Air Station North Island in San Diego to insure
all systems are functioning properly, before moving offshore. This
ensures proper system operation and avoids loss of limited training
time, expenditure of fuel, and cumulative engine use in the event of
equipment malfunction. The potential effects of dipping sonar have been
accounted for in the Navy's analysis. Further, due to lower power
settings for dipping sonar, potential behavioral impact ranges of
dipping sonar are significantly lower than surface ship sonars. For
example, the HSTT average modeled range to temporary threshold shift of
dipping sonar for a 1-second ping on low-frequency cetacean (i.e., blue
whale) is 77 m (HSTT FEIS/OEIS Table 3.7-7). This range is easily
monitored for large whales by a hovering helicopter and is accounted
for in the Navy's proposed mitigation ranges for dipping sonars.
Limited ping time and lower power settings therefore would limit the
impact from dipping sonar to any marine mammal species. It should be
pointed out that the commenter's recommendation is based on new Navy
behavioral response research specific to beaked whales (Falcone et al.,
2017). The Navy relied upon the best science that was available to
develop behavioral response functions in consultation with NMFS for the
HSTT FEIS/OEIS. The article cited in the comment (Falcone et al., 2017)
was not available at the time the HSTT EIS/OEIS was published. The new
information and data presented in the article was thoroughly reviewed
when it became available and further considered in discussions with
some of the paper's authors. Many of the variables requiring further
analysis for beaked whales and dipping sonar impact assessment are
still being researched under continued Navy funding through 2019. The
small portion of designated Kilo Dip areas that overlap the southern
part of the San Diego Arc is not of sufficient depth for preferred
habitat of beaked whales (see Figure 2.1-9 in the HSTT FEIS/OEIS).
Further, passive acoustic monitoring for the past several years in the
San Diego Arc confirms a lack of beaked whale detections (Rice et al.,
2017). Also, behavioral responses of beaked whales from dipping and
other sonars cannot be universally applied to other species including
blue whales. Navy-funded behavioral response studies of blue whales to
simulated surface ship sonar has demonstrated there are distinct
individual variations as well as strong behavioral state considerations
that influence any response or lack of response (Goldbogen et al.,
2013).
Comment 41: A commenter recommends requiring vessel speed
restrictions within the San Diego Arc Mitigation Area.
Response: Previously, the Navy commissioned a vessel density and
speed report for the HSTT Study Area (CNA, 2016). Based on an analysis
of Navy ship traffic in the HSTT Study Area between 2011 and 2015,
median speed of all Navy vessels within Southern California is
typically already low, with median speeds between 5 and 12 kn (CAN,
2016). Slowest speeds occurred closer to the coast including the
general area of the San Diego Arc and approaches to San Diego Bay. The
presence and transits of commercial and recreational vessels, numbering
in the many hundreds, far outweighs the presence of Navy vessels.
According the the SARs, blue whale mortality and injuries attributed to
commercial ship strikes in California waters was zero in the most
recent reporting period between 2011 and 2015 (Carretta et al., 2017a).
However, ship strikes were implicated in the deaths of four blue whales
and the serious injury of a fifth whale between 2009 and 2013 (Carretta
et al., 2015). There has been no confirmed Navy ship strike to a blue
whale in the entire Pacific over the 13-year period from 2005 to 2017.
To minimize the possibility of ship strike in the San Diego Arc
Mitigation Area, the Navy will implement procedural mitigation for
vessel movements based on guidance from NMFS for vessel strike
avoidance. The Navy will also issue seasonal awareness notification
messages to all Navy vessel of blue, fin, and gray whale occurrence to
increase ships awareness of marine mammal presence as a means of
improving detection and avoidance of whales in SOCAL. When developing
the mitigation for this 2018-2023 rule, the Navy analyzed the potential
for implementing additional types of mitigation, such as developing
vessel speed restrictions within the HSTT Study Area. The Navy
determined that based on how the training and testing activities will
be conducted within the HSTT Study Area under the planned activities,
vessel speed restrictions would be incompatible with the practicability
assessment criteria for safety, sustainability, and Title 10
requirements, as described in Section 5.3.4.1 (Vessel Movement) of the
HSTT FEIS/OEIS.
Comment 42: A commenter recommended prohibiting the use of air-
deployed mid-frequency active sonar in the Santa Barbara Island
Mitigation Area.
Response: The commenter requested to prohibit ``air-deployed'' mid-
frequency active sonar is based on one paper (Falcone et al., 2017),
which is a Navy-funded project designed to study behavioral responses
of a single species, Cuvier's beaked whales, to mid-frequency active
sonar. The Navy relied upon the best science that was available to
develop behavioral response functions for beaked whales and other
marine mammals in consultation with NMFS for the HSTT FEIS/OEIS. The
article cited in the comment (Falcone et al., 2017) was not available
at the time the HSTT DEIS/OEIS was published but does not change the
HSTT FEIS/OEIS criteria or conclusions. The new information and data
presented in the article were thoroughly reviewed when they became
available and further considered in discussions with some of the
paper's authors. Many of the variables requiring further analysis for
beaked whales and dipping sonar impact assessment are still being
researched under continued Navy funding through 2019.
Behavioral responses of beaked whales from dipping and other sonars
cannot be universally applied to other marine mammal species. For
example, Navy-funded behavioral response studies of blue whales to
simulated surface ship sonar has demonstrated there are distinct
individual variations as well as strong behavioral state considerations
that influence any response or lack of response (Goldbogen et al.,
2013). The same conclusion on the importance of exposure and behavioral
context was stressed by Harris et al. (2017). Therefore, it is expected
that other species would also have highly variable individual responses
ranging from some response to no response to any anthropogenic sound.
This variability is accounted for in the Navy's current behavioral
response curves described in the HSTT FEIS/OEIS and supporting
technical reports.
[[Page 66893]]
The potential effects of dipping sonar have been rigorously
accounted for in the Navy's analysis. Parameters such as power level
and propagation range for typical dipping sonar use are factored into
HSTT acoustic impact analysis along with guild specific criteria and
other modeling variables as detailed in the HSTT FEIS/OEIS and
associated technical reports for criteria and acoustic modeling. Due to
lower power settings for dipping sonar, potential impact ranges of
dipping sonar are significantly lower than surface ship sonars. For
example, the HSTT average modeled range to temporary threshold shift of
dipping sonar for a 1-second ping on low-frequency cetacean (i.e., blue
whale) is 77 m, and for mid-frequency cetaceans including beaked whales
is 22 m (HSTT FEIS/OEIS Table 3.7-7). This range is monitored for
marine mammals by a hovering helicopter and is accounted for in the
Navy's proposed mitigation ranges for dipping sonars (200 yd. or 183
m). Limited ping time and lower power settings therefore would limit
the impact from dipping sonar to any marine mammal species.
For other marine mammal species, the small area around Santa
Barbara Island does not have resident marine mammals, formally
identified biologically important areas, nor is it identified as a
breeding or persistent foraging location for cetaceans. Instead, the
same marine mammals that range throughout the offshore Southern
California area could pass at some point through the marine waters of
Santa Barbara Island. As discussed in Appendix K (Geographic Mitigation
Assessment) of the HSTT FEIS/OEIS, the Navy is already proposing year-
round limitations to mid-frequency active sonar and larger explosive
use. The Navy will not use MF1 surface ship hull-mounted mid-frequency
active sonar during training or testing, or explosives that could
potentially result in the take of marine mammals during medium-caliber
or large-caliber gunnery, torpedo, bombing, and missile (including
2.75'' rockets) activities during training in the Santa Barbara Island
Mitigation Area. Other mid-frequency active sonar systems for which the
Navy is seeking authorization within SOCAL are used less frequently
than surface ship sonars, and more importantly are of much lower power
with correspondingly lower propagation ranges and reduced potential
behavioral impacts.
Comment 43: A commenter recommended prohibiting other sources of
mid-frequency active sonar in the Santa Barbara Mitigation Area.
Response: Appendix K (Geographic Mitigation Assessment) discusses
the Navy's analysis of mid-frequency active sonar restrictions around
Santa Barbara Island. Other training mid-frequency active sonar (MFAS)
systems are likely to be used less frequently in the vicinity Santa
Barbara Island than surface ship mid-frequency active sonars. Although
not prohibiting the use of other sources of MFAS, the Navy will not use
MF1 surface ship hull-mounted mid-frequency active sonar during
training or testing, or explosives that could potentially result in the
take of marine mammals during medium-caliber or large-caliber gunnery,
torpedo, bombing, and missile (including 2.75'' rockets) activities
during training in the Santa Barbara Island Mitigation Area.
Comment 44: A commenter recommended implementing vessel speed
restrictions in the Santa Barbara Island Mitigation Area (Channel
Islands Sanctuary Cautionary Area).
Response: The Channel Islands Sanctuary Cautionary Area was renamed
the Santa Barbara Island Mitigation Area for the proposed rule. All
locations within the HSTT Study Area have been used for Navy training
and testing for decades. There has been no scientific evidence to
indicate the Navy's activities are having adverse effects on
populations of marine mammals, many of which continue to increase in
number or are maintaining populations based on what regional conditions
can support. This includes any marine mammal population that may
transit through the Santa Barbara Island Mitigation Area. For example,
the most recent NMFS U.S. West Coast survey findings (Moore and Barlow,
2017) encountered the highest estimated abundance of Mesoplodon beaked
whales in the California Current since 1991. Multiple other surveys,
monitoring efforts, and research projects continue to encounter long-
term resident individuals such as populations of beaked whales in
higher densities within the HSTT Study Area where various sonar systems
have been in use for decades; see for example citation in the HSTT
FEIS/OEIS to Debich et al. (2015a, 2015b), Falcone and Schorr (2012,
2014), Hildebrand et al. (2009), Moretti (2016), [Scaron]irovi[cacute]
et al. (2016), and Smultea and Jefferson (2014). The newest Navy-funded
research, which was not available when the HSTT FEIS/OEIS was issued,
continue to support the regular and repeated occurrence of marine
mammal populations in HSTT including those thought most susceptible to
behavioral response to anthropogenic sounds (DiMarzio et al., 2018;
Lewis and [Scaron]irovi[cacute], in press; Moretti et al., 2017; Schorr
et al., 2018; [Scaron]irovi[cacute] et al., 2016, 2017, 2018;
[Scaron]irovi[cacute] et al., 2018). Navy research and monitoring
funding continues within the HSTT Study Area under current NMFS MMPA
and ESA permits, and is planned through the duration of any future
permits. Given the lack of effects to marine mammal populations in the
HSTT Study Area from surface ship sonars, the effects from
intermittent, less frequent use of lower powered dipping mid-frequency
active sonar or other mid-frequency active sonar and low-frequency
sonars would also not significantly affect local populations.
Additionally, here has not been any Navy ship strike to marine
mammals in SOCAL over the 8-year period from 2010-2018, and there has
never been a Navy strike within the boundary of the Channel Islands
National Marine Sanctuary over the course of strike record collection
dating back 20 years. Therefore, ship strike risk to marine mammals
transiting the Santa Barbara Island Mitigation Area is minimal.
Additionally, as detailed in the analysis in the HSTT FEIS/OEIS Section
3.7.3.4.1 (Impacts from Vessels and In-Water Devices) and in Appendix K
(Geographic Mitigation Assessment), there are important differences
between most Navy vessels and their operation and commercial ships that
individually make Navy vessels much less likely to strike a whale. Navy
vessels already operate at a safe speed given a particular transit or
activity need. This also includes a provision to avoid large whales by
500 yd; so long as safety of navigation and safety of operations is
maintained. Previously, the Navy commissioned a vessel density and
speed report for HSTT (CNA, 2016). Based on an analysis of Navy ship
traffic in HSTT between 2011 and 2015, the average speed of all Navy
vessels within Southern California is typically already low, with
median speeds between 5 and 12 kn (CNA, 2016). Slowest speeds occurred
closer to the coast and islands. However, sometimes during training or
testing activities, higher speeds are required.
Finally, given the lack of population impact to marine species
throughout SOCAL from Navy activities, lack of significant and repeated
use of the small portion of waters within the Santa Barbara Island
Mitigation Area by marine mammals, anticipated low individual residency
times within the Mitigation Area, application of mitigation and
protective measures as outlined in the HSTT FEIS/OEIS, documented safe
speeds Navy vessels already navigate by, detailed
[[Page 66894]]
assessments of realistic training and testing requirements and
potential impacts of further restrictions, the Navy has adequately
defined the most practicable mitigation measures in the HSTT FEIS/OEIS
and Appendix K (Geographic Mitigation Assessment).
Comment 45: A commenter recommended additional mitigation areas for
important beaked whale habitat in the Southern California Bight. A
commenter asserted that it is important to focus substantial management
efforts on beaked whales within the Navy's SOCAL Range Complex, which
sees the greatest annual amount of sonar and explosives activity of any
Navy range in the Pacific.
Response: The basis for this comment includes incorrect or outdated
information or information that does not reflect the environment
present in the HSTT Study Area, such as, ``. . .beaked whale
populations in the California Current have shown significant, possibly
drastic declines in abundance over the last twenty years.'' The
citation provided in the footnote to the comment and postulated
``decline'' was for beaked whales up until 2008 (which does not take
into account information from the last 10 years) and was a postulated
trend for the entire U.S. West Coast, not data which is specific to the
HSTT Study Area. As noted in Section 3.7.3.1.1.7 (Long-Term
Consequences) of the HSTT FEIS/OEIS, the postulated decline was in fact
not present within the SOCAL portion of the HSTT Study Area, where
abundances of beaked whales have remained higher than other locations
off the U.S. West Coast. In addition, the authors of the 2013 citation
(Moore and Barlow, 2013) have published trends based on survey data
gathered since 2008 for beaked whales in the California Current, which
now includes the highest abundance estimate in the history of these
surveys (Barlow 2016; Carretta et al., 2017; Moore and Barlow, 2017).
Also, when considering the portion of the beaked whale population
within the SOCAL portion of the HSTT Study Area and as presented in the
HSTT FEIS/OEIS, multiple studies have documented continued high
abundance of beaked whales and the long-term residency of documented
individual beaked whales, specifically where the Navy has been training
and testing for decades (see for example Debich et al., 2015a, 2015b;
Dimarzio et al., 2018; Falcone and Schorr, 2012, 2014; Hildebrand et
al., 2009; Moretti, 2016; Schorr et al., 2018; [Scaron]irovi[cacute] et
al., 2016; Smultea and Jefferson, 2014). There is no evidence that
there have been any population-level impacts to beaked whales resulting
from Navy training and testing in the SOCAL portion of the HSTT Study
Area. The Navy did provide analysis and consideration of additional
geographic mitigation for beaked whales in the Southern California
Bight in Appendix K (Geographic Mitigation Assessment), Section K.7.2
(Southern California Public Comment Mitigation Area Assessment) and
specifically Section K.7.2.7 (Northern Catalina Basin and the San
Clemente Basin) of the HSTT FEIS/OEIS regarding the stated concern over
the possible presence of Perrin's beaked whale. See Chapter 5
(Mitigation), Section 5.4.1.2 (Mitigation Area Assessment) of the HSTT
FEIS/OEIS for additional details regarding the assessments of areas
considered for mitigation.
Comment 46: A commenter recommended additional mitigation areas in
the San Nicholas Basin. A commenter notes that the settlement agreement
established a ``refuge'' from sonar and explosives activities in a
portion of the whales' secondary habitat, outside the Southern
California Anti-submarine Warfare Range (SOAR), with more management
effort being necessary in the long term a commenter recommended at a
minimum that NMFS should prescribe the ``refuge'' during the next five-
year operation period and should consider all possible habitat-based
management efforts, including but not limited to the expansion of this
area further south towards SOAR, to address impacts on the small
population of Cuvier's beaked whales associated with San Clemente
Island. A commenter also commented the energetic costs of displacement
of beaked whales into sub-optimal foraging habitat outweigh the costs
of repeated sonar exposure for whale survival, while creating
conditions of a population sink, such as has been seen on the Navy's
AUTEC range (Claridge 2013).
Response: Navy did provide analysis and consideration of additional
geographic mitigation for beaked whales in the San Nicolas Basin in
Appendix K (Geographic Mitigation Assessment), Section K.7.2 (Southern
California Public Comment Mitigation Area Assessment) and specifically
Section K.7.2.1 (San Nicolas Basin) of the HSTT FEIS/OEIS. See Chapter
5 (Mitigation), Section 5.4.1.2 (Mitigation Area Assessment) of the
HSTT FEIS/OEIS for additional details regarding the assessments of
areas considered for mitigation.
Within San Nicolas Basin, there is a documented, recurring number
of Cuvier's beaked whales strongly indicating that the Navy's
activities areis not having a population-level impact to this species.
This is supported by repeated visual re-sighting rates of individuals,
sightings of calves and, more importantly, reproductive females, and
passive acoustic assessments of steady vocalization rates and abundance
over at least the most recent seven-year interval. It is incorrect to
consider as fact that there is a ``population sink, such as has been
seen on the Navy's AUTEC range. In the citation provided (Claridge
2013), that statement is merely a hypothesis, yet to be demonstrated.
The Navy has been funding Cuvier's beaked whale research
specifically in San Nicolas Basin since 2006. This research is planned
to continue for at least the next five years through the duration of
the planned HSTT MMPA permit. Cumulative from 2006 to 2016, over 170
individual Cuvier's beaked whales have been catalogued within San
Nicolas Basin. Schorr et al. (2018) state for the most recent field
season from 2016 to 2017 that: Identification photos of suitable
quality were collected from 69 of the estimated 81 individual Cuvier's
beaked whales encountered in 2016-2017. These represented 48 unique
individuals, with eight of these whales sighted on two different days,
and another three on three different days during the study period.
Nineteen (39 percent) of these whales had been sighted in previous
years. Many more whales identified in 2016 had been sighted in a
previous year (16/28 individuals, 57 percent), compared to 2017 (5/22
individuals, 23 percent), though both years had sightings of whales
seen as early as 2007. There were three adult females photographed in
2016 that had been sighted with calves in previous years, one of which
was associated with her second calf. Additionally, a fourth adult
female, first identified in 2015 without a calf, was subsequently
sighted with a calf. The latter whale was sighted for a third
consecutive year in 2017, this time without a calf, along with two
other adult females with calves who had not been previously sighted.
These sightings of known reproductive females with and without calves
over time (n = 45) are providing critically needed calving and weaning
rate data for Population Consequences of Disturbance (PcoD) models
currently being developed for this species on SOAR.
In 2018, an estimate of overall abundance of Cuvier's beaked whales
at the Navy's instrumented range in San Nicolas Basin was obtained
using new dive-counting acoustic methods and an archive of passive
acoustic M3R data representing 35,416 hours of data (DiMarzio, 2018;
Moretti, 2017). Over the seven-year interval from 2010-2017,
[[Page 66895]]
there was no observed change and perhaps a slight increase in annual
Cuvier's beaked whale abundance within San Nicolas Basin (DiMarzio
2018). There does appear to be a repeated dip in population numbers and
associated echolocation clicks during the fall centered around August
and September (DiMarzio, 2018; Moretti, 2017). A similar August and
September dip was noted by researchers using stand-alone off-range
bottom passive acoustic devices in Southern California (Rice et al.,
2017; [Scaron]irovi[cacute] et al., 2016). This dip in abundance
documented over 10 years of monitoring may be tied to some as yet
unknown population dynamic or oceanographic and prey availability
dynamic. It is unknown scientifically if this represents a movement to
different areas by parts of the population, or a change in behavioral
states without movement (i.e., breeding verse foraging). Navy training
and testing events are spatially and temporally spread out across the
SOCAL portion of the HSTT Study Area. In some years events occur in the
fall, yet in other years events do not. Yet, the same dip has
consistently been observed lending further evidence this is likely a
population biological function.
Comment 47: A commenter recommended additional mitigation areas in
the Santa Catalina Basin. A commenter commented that there is likely a
small, resident population of Cuvier's beaked whales resides in the
Santa Catalina Basin and that this population is subject to regular
acoustic disturbance due to the presence of the Shore Bombardment Area
(SHOBA) and 3803XX. The population may also be exposed to training
activities that occupy waters between Santa Catalina and San Clemente
Islands. Similar to the San Nicholas population, the settlement
agreement established a ``refuge'' from sonar and explosives activities
in the northern portion of the Santa Catalina Basin. A commenter
recommended that, at a minimum the Navy should carefully consider
implementing the ``refuge'' during the next five-year authorization
period and should continue to consider all possible habitat-based
management efforts to address impacts on the population.
Response: The water space areas mentioned in the comment as
``(SHOBA)'' off the southern end of San Clemente Island are waters
designated as Federal Danger and Safety Zones via formal rule making
(Danger Zone--33 CFR 334.950 and Safety Zone--33 CFR 165.1141) because
they are adjacent to the shore bombardment impact area that is on land
at the southern end of San Clemente Island. Waters designated as
``3803XX,'' which are associated with the Wilson Cove anchorages and
moorings, where ship calibration tests, sonobuoy lot testing, and
special projects take place, are designated as Federal Safety and
Restricted Zones via formal rule making (Safety Zone--33 CFR 165.1141
and Restricted Zone--33 CFR 334.920).
The comment states a concern that a population of Cuvier's beaked
whale is, ``subject to regular acoustic disturbance due to the presence
of the Shore Bombardment Area,'' is not correct. The SHOBA is a naval
gun impact area located on land at the southern end of San Clemente
Island. This area is an instrumented land training range used for a
variety of bombardment training and testing activities. The in-water
administrative boundary for SHOBA does not delineate the locations
where a ship firing at land targets must be located and does not
represent where gunfire rounds are targeted. The water area in Santa
Catalina Basin is a controlled safety zone in the very unlikely event a
round goes over the island and lands in the water. With the modern
advent of better precision munitions, computers, and advanced fire
control, that probability is very remote. Navy vessels use the waters
south of San Clemente Island (SHOBA West and SHOBA East) from which to
fire into land targets on southern San Clemente Island (see the HSTT
FEIS/OEIS Figure 2.1-7). Therefore, there would not be any underwater
acoustic disturbance to Cuvier's beaked whales located within the Santa
Catalina Basin from in-water explosives or ship firing.
Comment 48: A commenter recommended additional mitigation areas for
the southernmost edge of the California Current, west of Tanner and
Cortes Banks. In light of the importance of the Southernmost edge of
the California Current, west of Tanner and Cortes banks, Commenters
recommend assessing the designation of the southern offshore waters of
the Southern California Bight as a seasonal time-area management area
for Cuvier's beaked whales between November and June. The approximate
coordinates are 32.75 N, 119.46 W (referenced as Site E). As part of
this assessment, a commenter recommended that the boundaries be refined
via expert consideration of acoustic and other relevant information
pertaining to beaked whale biology and bathymetric and oceanographic
data.
Response: Baumann-Pickering et al. (2014a, b, 2015), as the
commenter referenced, did not specify this area as biologically
important and the author's data only indicated there have been
detections of the Cuvier's beaked whales within this area. Further, the
species is widely distributed within Southern California and across the
Pacific with almost all suitable deep water habitat greater than 800 m
in Southern California conceivably containing Cuvier's beaked whales.
Only limited population vital rates exist for beaked whales, covering
numbers of animals, populations vs. subpopulations determination, and
residency time for individual animals (Schorr et al., 2017, 2018). The
science of passive acoustic monitoring is positioned to answer some
questions on occurrence and seasonality of beaked whales, but cannot as
of yet address all fundamental population parameters including
individual residency time.
Furthermore, while passive acoustic monitoring within Southern
California has been ongoing for 28 years, with many sites funded by the
Navy, not all sites have been consecutively monitored for each year.
All of the single bottom-mounted passive acoustic devices used for the
analysis by Baumann-Pickering et al. (2014a, b, 2015), and used in the
comment to support its argument, are not continuous and have various
periodicities from which data have been collected. Specifically,
devices have been deployed and removed from various locations with some
sites having multiple years of data, others significantly less, with
perhaps just a few months out of a year. For instance, Site E, located
west of Tanner and Cortes Banks and used by the commenter to justify
restrictions in this area, was only monitored for 322 days from
September 2006 through July 2009 (obtaining slightly less than a full
year's worth of data).
Site E was also used again for another 63 days from Dec 2010
through February 2011. During this second monitoring period at Site E,
Gassman et al. (2015) reported detection of only three Cuvier's beaked
whales over six separate encounters with time intervals of 10-33
minutes. As sources of data associated with a single monitoring point,
the two monitoring episodes conducted at Site E may not be indicative
of Cuvier's beaked whale presence at other locations within Southern
California, which lack comparable monitoring devices. Nor would they be
indicative of overall importance or lack of importance of the area west
of Tanner and Cortes Banks. Further, more recent acoustic sampling of
bathymetrically featureless areas off Southern California with drifting
hydrophones conducted by NMFS, detected many beaked whales over abyssal
plains and not associated with
[[Page 66896]]
slope or seamount features. This counters a common misperception that
beaked whales are primarily found over slope waters, in deep basins, or
over seamounts (Griffins and Barlow 2016).
Most importantly, older passive acoustic data prior to 2009 may not
be indicative of current or future occurrence of beaked whales,
especially in terms of potential impact of climate change on species
distributions within Southern California. To summarize, these limited
periods of monitoring (322 days in a three-year period prior to 2010
and 63 days in 2011) may or may not be reflective of current beaked
whale distributions within Southern California and into the future.
Furthermore, passive acoustic-only detection of beaked whales, without
additional population parameters, can only determine relative
occurrence, which could be highly variable over sub-regions and through
time.
While Cuvier's beaked whales have been detected west of Tanner and
Cortes Banks, as noted above this species is also detected in most all
Southern California locations greater than 800 m in depth. Furthermore,
the Navy has been training and testing in and around Tanner and Cortes
Banks with the same basic systems for over 40 years, with no evidence
of any adverse impacts having occurred. Further, there are no
indications that Navy training and testing in the Southern California
portion of the HSTT Study Area has had any adverse impacts on
populations of beaked whales in Southern California. In particular, a
re-occurring population of Cuvier's beaked whales co-exists within San
Nicolas Basin to the east, an area with significantly more in-water
sonar use than west of Tanner and Cortes Banks.
To gain further knowledge on the presence of beaked whales in
Southern California, the Navy continues to fund additional passive
acoustic field monitoring, as well as research advancements for density
derivation from passive acoustic data. For the five-year period from
2013 to 2017, U.S. Pacific Fleet on behalf of the U.S. Navy funded
$14.2 million in marine species monitoring within Hawaii and Southern
California. Specifically, in terms of beaked whales, the Navy has been
funding beaked whale population dynamics, tagging, and passive acoustic
studies within the HSTT Study Area since 2007 (DiMarzio et al., 2018;
Moretti, 2017; Rice et al., 2017, Schorr et al., 2017, 2018;
[Scaron]irovi[cacute], et al., 2017). Variations of these efforts are
planned to continue through the duration of the next HSTT MMPA permit
cycle using a variety of passive acoustic, visual, tagging, photo ID,
and genetics research tools. This Navy effort is in addition and
complementary to any planned NMFS efforts for beaked whales and other
marine mammals. For instance, the Navy is co-funding with NMFS and the
Bureau of Ocean Energy Management a planned Summer-Fall 2018 visual and
passive acoustic survey along the U.S. West Coast and off Baja Mexico.
New passive detection technologies focusing on beaked whales will be
deployed during these surveys (similar to Griffiths and Barlow, 2016).
The Navy continues SOCAL beaked whale occurrence and impact studies
with additional effort anticipated through 2020.
Analysis of the southernmost edge of the California Current, west
of Tanner-Cortes Bank and the presence of Cuvier's beaked whales was
addressed in Appendix K (Geographic Mitigation Assessment), Section
K.7.2.4 (Southernmost Edge of California Current, West of Tanner-Cortes
Bank) and Section K.7.2.6 (Cuvier's Beaked Whale Habitat Areas
Mitigation Assessment) of the HSTT FEIS/OEIS. Also see Chapter 3,
Section 3.7.2.3.24 (Cuvier's Beaked Whale (Ziphius cavirostris)) of the
HSTT FEIS/OEIS for additional information regarding this species.
As noted in Appendix K (Geographic Mitigation Assessment), the
waters west of Tanner and Cortes Banks are also critical to the Navy's
training and testing activities; therefore, it is not practicable to
preclude activities within that water space in the SOCAL portion of the
HSTT Study Area. Reasonable mitigation measures, as discussed in
Appendix K (Geographic Mitigation Assessment), would limit the impact
of training and testing on marine mammals, and especially beaked
whales, in this area.
Given that there is no evidence that Navy training and testing
activities are having significant impacts to population of beaked
whales anywhere in the SOCAL portion of the HSTT Study Area, the
uncertainty of current use by Cuvier's beaked whales of the area west
of Tanner and Cortes Banks, the fact that general occurrence of beaked
whales in Southern California may not necessarily equate to factors
typically associated with biologically important areas, and
consideration of the importance of Navy training and testing activities
in the areas around Tanner and Cortes Banks discussed in Appendix K
(Geographic Mitigation Assessment) of the HSTT FEIS/OEIS, additional
geographic mitigation specifically for the area west of Tanner and
Cortes Banks is not warranted.
As noted in Appendix K (Geographic Mitigation Assessment) and
Chapter 5 (Mitigation), Section 5.3 (Procedural Mitigation to be
Implemented) of the HSTT FEIS/OEIS, the Navy will continue to implement
procedural mitigation measures throughout the HSTT Study Area.
Comment 49: A commenter commented that the same long-term passive
acoustic study of the Southern California Bight as discussed for
Cuvier's beaked whales above in Comment 48 also suggests that southern-
central waters represent biologically important habitat for Perrin's
beaked whale. A commenter recommended that the Northern Catalina Basin
and the waters southeast of Santa Catalina Island (approximate
coordinates of 33.28 N, -118.25 W), and the San Clemente Basin
(approximate coordinates of 32.52 N, -118.32 W), both based on location
of HARP deployments (referenced as sites ``A'' and ``S''), be
considered as management areas for Perrin's beaked whales. A commenter
recommended that the boundaries of any restrictions be established via
expert consideration.
Response: All of the single bottom-mounted passive acoustic devices
used for the analysis by Baumann-Pickering et al. (2014) and used by
the commenter to support their argument are not continuous and have
various periodicities for which data have been collected. As single
point sources of data, these passive acoustic devices may not be
indicative of Perrin's beaked whale presence at other locations within
Southern California without comparable devices. Nor would older data
prior to 2009 be indicative of current or future occurrence especially
in terms of potential impact of climate change on species
distributions.
Navy-funded passive acoustic monitoring within the SOCAL portion of
the HSTT Study Area has been ongoing for the past 21 years, but not all
areas are monitored continuously, and devices have been deployed and
removed from various locations. Santa Catalina Basin was only monitored
from August 2005 to July 2009. Santa Catalina Basin has not been
monitored under Navy funding since 2009 because other areas in Southern
California were prioritized for passive acoustic device placement by
the researchers. For San Clemente Island, the single monitoring site
``S'' used in Baumann-Pickering et al. (2014) and cited as the source
of the comment's claim for San Clemente Basin was only deployed for a
limited time of approximately 1.5 years, resulting in 409 days of data
(September 2009-May 2011). For both sites
[[Page 66897]]
combined, only 41 hours of BW43 signal types were detected over a
cumulative approximately five-and-a-half years of monitoring. The 41
hours of BW43 detections therefore only represents a small fraction of
overall recording time (less than 1 percent).
The beaked whale signal type detected called BW43 has been
suggested as coming from Perrin's beaked whales (Baumann-Pickering et
al. 2014), but not yet conclusively and scientifically confirmed.
A different Navy-funded single site south of San Clemente Island
within the San Clemente Basin has had a passive acoustic device in
place from July 2014 through current. [Scaron]irovi[cacute] et al.
(2016) and Rice et al. (2017) contain the most current results from San
Clemente Basin site ``N.'' While [Scaron]irovi[cacute] et al. (2016)
and Rice et al. (2017) do report periodic passive acoustic detections
of Mesoplodon beaked whales thought to be Perrin's beaked whale in San
Clemente Basin, the overall detection rate, periodicity, and occurrence
has not been high. Between May 2015 and June 2016, there were only
seven weeks in which potential Perrin's beaked whale echolocation
clicks were detected, with each week having less than 0.14 hours/week
of detections. Acoustic sampling of bathymetrically featureless areas
off Southern California with drifting hydrophones by NMFS detected many
beaked whales over abyssal plains and not always associated with slope
or seamount features, which counters a common misperception that beaked
whales are primarily found over slope waters, in deep basins, or over
seamounts (Griffins and Barlow 2016). One of these devices was deployed
within the SOCAL portion of the HSTT Study Area. In addition, analysis
of NMFS visual survey data from 2014, the most recent year available,
showed an increase in Mesoplodon beaked whales along the entire U.S.
West Coast, which the authors attributed to an influx of tropical
species of Mesoplodon during the unusually warm water condition that
year (Barlow 2016; Moore & Barlow 2017). Perrin's beaked whale, part of
the Mesoplodon guild, could be part of these sightings. In summary, San
Clemente Basin and Santa Catalina Basin with similar low passive
acoustic detection rates are likely to be part of Perrin beaked whale's
general distribution along the U.S. West Coast and in particular
Southern California and Baja Mexico. This distribution is likely to be
wide ranging for Perrin's beaked whales as a species and highly
correlated to annual oceanographic conditions. Santa Catalina and San
Clemente basins do have infrequent suspected Perrin's beaked whale
passive acoustic detections from a limited number of devices, but these
areas may not specifically represent unique high occurrence locations
warranting geographic protection beyond existing Navy protective
measures.
The Navy has been training and testing in and around the Northern
Catalina Basin and waters southeast of Santa Catalina Island with the
same systems for over 40 years, and there is no evidence of any adverse
impacts having occurred and no indications that Navy training and
testing has had any adverse impacts on populations of beaked whales in
Southern California. The main source of anthropogenic noise in the
Catalina Basin and waters south of San Clemente Island are associated
with commercial vessel traffic concentrated in the northbound and
southbound lanes of the San Pedro Channel that runs next to Santa
Catalina Island and leads to and from the ports of Los Angeles/Long
Beach and other commercial traffic from San Diego and ports to the
north and south of Southern California. These waters in and around
Northern Catalina Basin and waters southeast of Santa Catalina Island
are critical to the Navy's training and testing activities, and so it
is not practicable to limit or reduce access or preclude activities
within that water space in the SOCAL portion of the HSTT Study Area.
The Santa Catalina Basin area and Perrin's beaked whales were
addressed in Appendix K (Geographic Mitigation Assessment), Section
K.7.2.3 (Catalina Basin) and K.7.2.7 (Northern Catalina Basin and the
San Clemente Basin) of the HSTT FEIS/OEIS. Also see Appendix K
(Geographic Mitigation Assessment), Section K.7.2.7.2 (Northern
Catalina Basin and Waters Southeast of Catalina Island Perrin's Beaked
Whale Habitat Mitigation Considerations) of the HSTT FEIS/OEIS for
additional information regarding this species. Additional limitations
as discussed in Appendix K (Geographic Mitigation Assessment) would
limit training and impact readiness. Given that there is no evidence of
impacts to the population of beaked whales in the area, and low
potential occurrence of Perrin's beaked whales in the Southern
California portion of the HSTT Study Area, geographic mitigation would
not effectively balance a reduction of biological impacts with an
acceptable level of impact on military readiness activities. As noted
in Appendix K (Geographic Mitigation Assessment) and Chapter 5, Section
5.3 (Procedural Mitigation to be Implemented) of the HSTT FEIS/OEIS,
the Navy will continue to implement procedural mitigation measures
throughout the HSTT Study Area.
Comment 50: Commenters recommended additional mitigation areas for
important fin whale habitat off Southern California. The commenters
recommended that the waters between the 200 m and 1000 m isobaths be
assessed for time-area management so that, at minimum, ship strike
awareness measures for fin whales can be implemented during the months
of November through February, when the whales aggregate in the area.
Response: As described and detailed in the HSTT FEIS/OEIS, the Navy
implements a number of ship-strike risk reduction measures for all
vessels, in all locations and seasons, and for all marine mammal
species. New research by [Scaron]irovi[cacute] et al. (2017) supports a
hypothesis that between the Gulf of California and Southern California,
there could be up to four distinct sub-populations based on fin whale
call types, including a Southern California resident population. There
is also evidence that there can be both sub-population shifts and
overlap within Southern California ([Scaron]irovi[cacute] et al.,
2017). Scales et al. (2017) also postulated two Southern California
sub-populations of fin whales based on satellite tagging and habitat
modeling. Scales et al. (2017) stated that some fin whales may not
follow the typical baleen whale migration paradigm, with some
individuals found in both warm, shallow nearshore waters <500 m, and
deeper cool waters over complex seafloor topographies. Collectively,
the author's spatial habitat models with highest predicted occurrence
for fin whales cover the entire core training and testing portion of
the SOCAL portion of the HSTT Study Area, not just areas between 200
and 1,000 m. Results from Navy-funded long-term satellite tagging of
fin whales in Southern and Central California still shows some
individual fin whales engage in wide-ranging movements along the U.S.
West Coast, as well as large daily movements well within subareas (Mate
et al., 2017). In support of further refining the science on Southern
California fin whales, Falcone and Schorr (2014) examined fin whale
movements through photo ID and short-to-medium term (days-to-several
weeks) satellite tag tracking under funding from the Navy. The authors
conducted small boat surveys from June 2010 through January 2014,
approximately three-and-a-half years. Of interest in terms of the
comment and the 200-1,000 m isobaths occurrence, more fin whale tag
locations were reported off the Palos Verdes
[[Page 66898]]
Peninsula and off of the Los Angeles/Long Beach commercial shipping
ports in fall, both areas north of and outside of the Navy's Southern
California Range Complex. Compared to the above areas, there were not
as many tag locations in the similar isobaths region off San Diego
associated with the Navy range area. Falcone and Schorr (2014) did
document an apparent inshore-offshore distribution between Winter-
Spring and Summer-Fall. Given the apparent resident nature of some fin
whales in Southern California as discussed in Falcone and Schorr
(2014), Scales et al. (2017), and [Scaron]irovi[cacute] et al. (2017),
it remains uncertain if the inshore-offshore seasonal pattern as well
as sub-population occurrence will persist into the future, or if fin
whales will change distribution based on oceanographic impacts on
available prey (ex. El Nino, climate change, etc.). The efforts from
Falcone and Schorr on fin whales began in 2010 and are planned to
continue for the next several years under Navy monitoring funding to
further refine fin whale population structure and occurrence within
Southern California.
The data from the various single bottom-mounted passive acoustic
devices used in the analysis are not continuous and have various
periodicities for which data have been collected. Many of these devices
are purposely placed in 200-1000 m of water. Given these are point
sources of data, they may or may not be indicative of fin whale calling
or presence at other locations within Southern California without
devices. Passive acoustic analysis is only useful for those individuals
that are calling and may not indicate total population occurrence. Low-
frequency fin whale calls by their very nature have relatively long
underwater propagation ranges so detections at a single device could
account for individuals 10-50 miles away if not further, depending on
local propagation conditions. This would mean calling whales are not in
the 200-1000 m area. [Scaron]irovi[cacute] et al. (2015) acknowledge in
discussing their data biases, that their use of ``call index'' may best
indicate a period of peak calling. But fin whales produce multiple call
types depending on behavioral state. Based on technology limitations,
some fin whale call types were not included in [Scaron]irovi[cacute] et
al. (2015).
1. The study cited by a commenter ([Scaron]irovi[cacute] et al.,
2015) and used as the basis for ``Figure 3'' concerns trends seen
within the Southern California Bight, not exclusively the SOCAL Range
Complex;
2. The research used as the basis for Figure 3 was funded by the
Navy to develop baseline information for the areas where Navy trains
and tests and was by no means designed to or otherwise intended as a
representative sample of all waters off California or the entire
habitat of the fin whale population in the area;
3. It is not correct to assume detected vocalizations (a ``call
index'') reported in [Scaron]irovi[cacute] et al. (2015) for fin whales
equates with where fin whales are aggregated in the Southern California
Bight. For example, the acoustic monitoring data did not pick up or
otherwise correspond to the observed seasonal distribution shift of fin
whales indicated by visual survey data covering the same time periods
(Campbell et al., 2015; Douglas et al., 2014);
4. [Scaron]irovi[cacute] et al. (2015) make no such claim of
aggregations during the winter months but instead compare call index
rates and state that the purpose for the paper was to demonstrate that
passive acoustics can be a powerful tool to monitor population trends,
not relative abundances;
5. There is no science to support the contention that fin whales
are ``at particular risk of ship-strike on the naval range.'' Two fin
whales were struck by the Navy in 2009 in the Southern California
portion of the HSTT Study Area as Navy noted in Appendix K (Geographic
Mitigation Assessment), but there have been no fin whales struck and in
fact no whales of any species struck in the subsequent nine-year period
despite a documented increase in the fin whale population inhabiting
the area (Barlow, 2016; Moore & Barlow, 2011; Smultea & Jefferson,
2014). Furthermore, one of those vessel strikes occurred at the end of
the recommended mitigation timeframe (February) and the other well
outside the time period (May), so the proposed mitigation would only
have been marginally effective, if at all. Neither of these Navy fin
whale strike locations were close to shore (both >50-60 Nmi from
shore), or associated with coastal shipping lanes. Based on an analysis
of Navy ship traffic in the HSTT Study Area between 2011 and 2015,
median speed of all Navy vessels within Southern California is
typically already low, with median speeds between 5 and 12 knots (CNA,
2016). This includes areas within and outside of 200-1000 m within
Southern California, with slowest speeds closer to the coast; and
6. As presented in the EIS/OEIS, fin whales are present off all the
waters of Southern California year-round ([Scaron]irovi[cacute] et al.,
2015, 2017). Using available quantitative density and distribution
mapping, the best available science, and expert elicitation, definitive
areas of importance for fin whales could not be determined by a panel
of scientists specifically attempting to do so (Calambokidis et al.,
2015).
Navy vessels already operate at a safe speed given a particular
transit or activity need. This also includes a provision to avoid large
whales by 500 yards, so long as safety of navigation and safety of
operations is maintained. Previously, the Navy commissioned a vessel
density and speed report for HSTT (CNA, 2016). Based on an analysis of
Navy ship traffic in HSTT between 2011 and 2015, median speed of all
Navy vessels within Southern California is typically already low, with
median speeds between 5 and 12 knots (CNA, 2016). Slowest speeds
occurred closer to the coast and islands.
In conclusion, speed restrictions within 200-1000 m is unwarranted
given the wide range of fin whale movements along the U.S. West Coast
including areas within and outside of 200-1000 m contours, sometimes
large-scale daily movements within regional areas as documented from
Navy-funded satellite tagging, the current lack of ship strike risk
from Navy vessels in Southern California (2010-2017), the already safe
training and testing ship speeds Navy uses within HSTT, and existing
Navy mitigation measures including provisions to avoid large whales by
500 yards where safe to do so.
In addition, the Navy agreed to send out seasonal awareness
messages of blue, fin, and gray whale occurrence to improve awareness
of all vessels operating to the presence of these species in SOCAL.
Hawaii Areas
Comment 51: NPS recommends that the Navy consider the following as
it plans to conduct activities in the HSTT Study Area. NPS notes units
of the NPS system that occur near training and testing areas around
Hawaii and identify which can be affected by noise. The Units are:
Kaloko-Honokohau National Historical Park (NHP), Pu'uhonua o Honaunau
NHP, Pu'ukolhola Heiau National Historic Site, Kalaupapa NHP, and the
World War II Valor in the Pacific National Monument.
Response: National Parks and Marine protected areas in are
addressed in Chapter 6 of the HSTT FEIS/OEIS. Kalaupapa National
Historical Park (NHP) is discussed in Comment 52 below. No planned
activities overlap with Kaloko-Honokohau NHP; therefore, no impacts are
expected within the Kalaupapa NHP. The Pu'uhonua o Honaunau NHP and
Pu'ukolhola Heiau National Historic Site are not specifically addressed
in Chapter 6 of
[[Page 66899]]
the FEIS/OEIS, but neither site appears to contain any marine waters.
The Navy's planned activities do not occur on land except in designated
training areas on Navy properties (i.e., for amphibious assaults,
etc.); therefore, there are no activities that overlap with these sites
and no impacts are expected. The WWII Valor in the Pacific Monument is
for the USS Arizona which is a Navy war memorial. No activities occur
within the boundary of the site itself, and the monument was not
designated to protect marine species. There are training and testing
activities that occur within Pearl Harbor as a whole, and impacts to
marine mammals in the waters of Pearl Harbor as a whole were include in
Navy's proposed activities and therefore analyzed by NMFS in this final
rule.
Comment 52: The NPS noted the presence of marine mammal species in
the Kalaupapa NHP (on the north shore of Molokai), and is concerned
about potential take of protected species that inhabit water out to
1000 fathoms, and recommended the Navy consider alternate training
areas to avoid impacts to these species. Species that occur year-round
include the false killer whale, sperm whale, pygmy sperm whale, spinner
dolphin, and bottlenose dolphin. Humpback whales are seasonal visitors
from November to April. The Hawaiian monk seal pups are within the
Kalaupapa NHP during the Spring and Summer.
Response: Part of the Kalaupapa NHP (northern portion) is protected
by the measures employed inside the 4-Islands Region Mitigation Area
such as year-round prohibition on explosives and no use of MF1 surface
ship hull mounted mid-frequency active sonar from November 15-April
15).
We note, however, that the majority of the Kalaupapa NHP is not in
the 4-Islands Region Mitigation Area as it is mainly landbased, but
just outside it. The Kalaupapa NHP was designated to protect the two
historic leper colonies on the property and was not designated with the
purpose of protecting marine species. The boundaries of the Kalaupapa
NHP extend a quarter mile offshore. The Navy does propose conducting
activities associated with the planned activities in the boundary of
the the Kalaupapa NHP. There would be no effect to Hawaiian monk seal
pupping on NHP land as the Navy does not have any planned activities in
the boundary of the Kalaupapa NHP, especially on land. The Navy's
planned activities do not include any land-based activities except for
a few activities which are conducted on designated Navy property (i.e.,
amphibious assaults on Silver Strand, etc.). Further, as the seaspace
adjacent to the Kalaupapa NHP is not an established training or testing
area, it is unlikely naval activity would occur in this area.
Comment 53: A commenter recommended expanding the Hawaii Island
Mitigation Area westward to protect resident Cuvier's beaked whales and
rough-toothed dolphins. The boundaries of the Hawaii Island Mitigation
Area should be expanded westward to remain consistent with the
boundaries of the BIAs defined in Baird et al. (2015), which informed
the boundaries of Conservation Council Settlement Areas 1-C and 1-D.
This expansion will cover habitat for Cuvier's beaked whales and
toothed dolphins that are resident around the Big Island.
Response: Analyses of the marine mammal species mentioned in the
comment and considered within the Hawaii Island Mitigation Area are
discussed throughout Appendix K (Geographic Mitigation Assessment),
Section K.3 (Biologically Important Areas within the Hawaii Range
Complex Portion of the HSTT Study Area) and Sections K.5.1 (Settlement
Areas Within the Hawaii Portion of the HSTT Study Area) through K.5.4
(Proposed Mitigation Areas that Overlap the Hawaii Portion of the HSTT
Settlement Agreement Areas) of the HSTT FEIS/OEIS. Additional
information on the marine mammals mentioned in the comment is also
provided in the species-specific sub-sections in Chapter 3, Section
3.7.2 (Affected Environment) of the HSTT FEIS/OEIS. Based on these
analyses, the Navy will implement additional mitigation within the
Hawaii Island Mitigation Area (year-round) as detailed in Chapter 5,
Section 5.4.2 (Mitigation Areas for Marine Mammals in the Hawaii Range
Complex) of the HSTT FEIS/OEIS, to further avoid or reduce impacts on
marine mammals from acoustic and explosive stressors from the planned
activities.
The mitigation requirement of prohibiting the use of explosives
year-round during training and testing across the entire Hawaii Island
Mitigation Area satisfies the previous mitigation requirement of a
prohibition on the use of in-water explosives for training and testing
activities of the Settlement Agreement for Areas 1-A, 1-C, and 1-D, and
further extends that requirement to the `Alenuih[amacr]h[amacr] Channel
(Area 1-B). The Hawaii Island Mitigation Area still includes 100
percent of Settlement Areas 1-C and 1-D and includes a large majority
of the BIAs for Cuvier's Beaked Whale (Hawaii Island BIA) and Rough-
Toothed Dolphins (Hawaii Island BIA) (the areas in question by this
comment). Particularly, it covers 93.30 percent of the Cuvier's Beaked
Whale BIA westward of Hawaii Island and 83.58 percent of Rough-toothed
dolphins Hawaii Island BIA westward of Hawaii Island.
Only the northern portion of the Cuvier's beaked whale BIA in
Alenuihaha Channel and a smaller offshore portion of the BIA west of
Hawaii are not covered by mitigations included in the Hawaii Island
Mitigation Area on the west and east of Hawaii Island. The BIAi s based
on the known range of the island-associated population, and the authors
suggest that ``the range of individuals from this population is likely
to increase as additional satellite-tag data become available'' (Baird
et al., 2015b). Cuvier's beaked whales are not expected to be displaced
from their habitat due to training and testing activities further
offshore in these small areas of the biologically important area, given
that the biologically important area covers 23,583 km\2\, is unbroken
and continuous surrounding the island, and the BIA likely
underrepresents their range. The small portion of the BIA that does not
overlap the Hawaii Island Mitigation Area is offshore, and according to
the most recent stock assessment approximately 95 percent of all
sighting locations were within 45 km of shore. Additionally,
consequences to individuals or populations are not unknown. No PTS is
estimated or authorized. A small numbers of TTS and Level B behavioral
harassment takes for Cuvier's beaked whales are estimated across the
entire Hawaii portion of the Study Area due to acoustic stressors. Most
of the TTS and Level B behavioral harassment takes for Cuvier's beaked
whales are associated with testing in the Hawaii Temporary Operating
Area, impacting the pelagic population (see Figure 3.7-36 of the HSTT
FEIS/OEIS). It is extremely unlikely that any modeled takes would be of
individuals in this small portion of the BIA that extends outside the
Hawaii Island Mitigation Area.
Long-term and relatively comprehensive research has found no
evidence of any apparent effects while documenting the continued
existence of multiple small and resident populations of various species
as well as long-term residency by individual beaked whales spanning the
length of the current studies that exceed a decade. Further, the Navy
has considered research showing that in specific contexts (such as
associated with urban noise, commercial vessel traffic, eco-tourism, or
whale watching, Chapter 3, Section 3.7.2.1.5.2 (Commercial Industries))
of
[[Page 66900]]
the HSTT FEIS/OEIS that chronic repeated displacement and foraging
disruption of populations with residency or high site fidelity can
result in population-level effects. As also detailed in the HSTT FEIS/
OEIS, however, the Navy training and testing activities do not equate
with the types of disturbance in this body of research, nor do they
rise to the level of chronic disturbance where such effects have been
demonstrated because Navy activities are typically sporadic and
dispersed. There is no evidence to suggest there have been any
population-level effects in the waters around Oahu, Kauai, and Niihau
or anywhere in the HSTT Study Area. In the waters around Oahu, Kauai,
and Niihau, documented long-term residency by individuals and the
existence of multiple small and resident populations are precisely
where Navy training and testing have been occurring for decades,
strongly suggesting a lack of significant impact to those individuals
and populations from the continuation of Navy training and testing.
Mark-recapture estimates derived from photographs of rough-toothed
dolphins taken between 2003 and 2006 resulted in a small and resident
population estimate of 198 around the island of Hawaii (Baird et al.,
2008), but those surveys were conducted primarily with 40 km of shore
and may underestimate the population. Data do suggest high site
fidelity and low population size for the island-associated population.
There are no tagging data to provide information about the range of the
island-associated population; the biologically important area is based
on sighting locations and encompasses 7,175 km2. Generally, this
species is typically found close to shore around oceanic islands. Only
approximately half of the BIA offshore is not covered by the Hawaii
Island Mitigation Area, where the BIA overlaps with special use
airspace. Consequences to individuals or populations are not unknown.
No PTS is estimated or authorized. Some TTS and Level B behavioral
harassment takes due to acoustic stressors for this species across the
entire HSTT Study Area (see Figure 3.7-66). Significant impacts on
rough-toothed dolphin natural behaviors or abandonment due to training
with sonar and other transducers are unlikely to occur within the small
and resident population area. A few minor to moderate TTS or Level B
behavioral harassment to an individual over the course of a year are
unlikely to have any significant costs or long-term consequences for
that individual, and nothing in the planned activities is expected to
cause a ``catastrophic event.'' The Navy operating areas west of Hawaii
Island are used commonly for larger events for a variety of reasons
described further in Section K.3 (Biologically Important Areas Within
the Hawaiian Range Complex Portion of the HSTT Study Area) (e.g., the
relatively large group of seamounts in the open ocean offers
challenging bathymetry in the open ocean far away from civilian vessel
traffic and air lanes where ships, submarines, and aircraft are
completely free to maneuver) and sonar may be used by a variety of
platforms. Enlarging the Hawaii Island Mitigation Area is not
anticipated to realistically reduce adverse impacts. Expanding the
Hawaii Island Mitigation Area has a limited likelihood of further
reducing impacts on marine mammal species or stocks and their habitat,
while these open ocean operating areas for important for training and
testing and, in consideration of these factors (and the broader least
practicable adverse impact considerations discussed in the
introduction), NMFS has determined that requiring this additional
mitigation is not appropriate.
Comment 54: A commenter recommended limiting MTEs to reduce
cumulative exposure in the Hawaii Island Mitigation Area.
Response: Prohibiting MTEs outright or spatially separating them
within the Hawaii Island Mitigation Area (which includes the formerly
named Planning Awareness Area) was proposed as additional mitigation to
ensure that ``marine mammal populations with highly discrete site
fidelity . . . are not exposed to MTEs within a single year.'' The goal
of geographic mitigation is not to be an absolute, outright barrier and
stop exposing animals to exercises per se; it is to reduce adverse
impacts to the maximum extent practicable. Impacts associated with
major training exercises, including cumulative impacts, are addressed
in Chapters 3 (Affected Environment and Environmental Consequences) and
Chapter 4 (Cumulative Impacts) of the HSTT FEIS/OEIS, and Navy
quantitative analysis using the best available science has determined
that training and testing activities will not have population-level
impacts on any species. As determined in Chapter 3, Section 3.7.4
(Summary of Potential Impacts on Marine Mammals) of the HSTT FEIS/OEIS,
it is not anticipated that the Proposed Action will result in
significant impacts to marine mammals. To date, the findings from
research and monitoring and the regulatory conclusions from previous
analyses by NMFS are that the majority of impacts from Navy training
and testing activities are not expected to have deleterious impacts on
the fitness of any individuals or long-term consequences to populations
of marine mammals.
MTEs cannot be moved around within the Hawaii Island Mitigation
Area, given that those activities are specifically located to leverage
particular features like the Alenuihaha Channel and the approaches to
Kawaihae Harbor. This recommendation is not, therefore, appropriate in
consideration of NMFS' least practicable adverse impact standard.
To limit activities, the Navy will not conduct more than 300 hours
of MF1 surface ship hull-mounted mid-frequency active sonar or 20 hours
of MF4 dipping sonar, or use explosives that could potentially result
in takes of marine mammals during training and testing in the Hawaii
Mitigation Area.
Comment 55: A commenter recommended prohibiting or restricting
other sources of mid-frequency active sonar in the Hawaii Island
Mitigation Area including prohibiting the use of helicopter-deployed
mid-frequency active sonar in the Hawaii Island Mitigation Area.
Response: The Navy is already limiting other sources of MFAS.
Between the application and the proposed rule, the Navy added new
mitigation that includes a limit to the annual use of helicopter
dipping sonar in the Hawaii Island Mitigation Area. Specifically, the
Navy will not conduct more than 20 hours of MF4 dipping sonar that
could potentially result in takes of marine mammals during training and
testing. Helicopters deploy MFAS from a hover position in bouts
generally lasting under 20 minutes, moving rapidly between sequential
deployment and their duration of use and source level (217 dB) are
generally well below those of hull-mounted frequency sonar (235 dB).
All locations within the HSTT Study Area have been used for Navy
training and testing for decades. There has been no scientific evidence
to indicate the Navy's activities are having adverse effects on
populations of marine mammals, many of which continue to increase in
number or are maintaining populations based on what regional conditions
can support. Navy research and monitoring funding continues within the
HSTT Study Area under current NMFS MMPA and ESA permits, and is planned
through the duration of any future permits. Given the lack of effects
to marine mammal populations in the HSTT Study Area from larger, more
powerful surface ship sonars, the effects from intermittent, less
[[Page 66901]]
frequent use of lower powered mid-frequency dipping sonar or other mid-
frequency active sonars would also not significantly affect small and
resident populations.
Comment 56: A commenter recommended extending the 4-Islands Region
Mitigation Area westward to encompass the Humpback Whale Special
Reporting Area in Kaiwi Channel. Additionally the 4-Island Region
Mitigation Area is inadequate to protect endangered Main Hawaiian
Island insular false killer whales as the Main Hawaiian Island insular
false killer whale is highly range-restricted to certain high-use
areas, one of which includes the ESA critical habitat and the BIA north
of Maui and Molokai (``False killer whale Hawaii Island to Niihau''
BIA).
Response: The portion of the special reporting area that extends
into Kaiwi Channel over Penguin Bank (equivalent to settlement area 2A)
is generally not a higher use area for Main Hawaiian Island insular
false killer whales and does not overlap significantly with the
biologically important area. As presented in Chapter 3 (Affected
Environment and Environmental Consequences), Navy quantitative analysis
indicates that significant impacts on false killer whale natural
behaviors or abandonment due to training with sonar and other
transducers are unlikely to occur within the entire small and resident
population area, let alone in the small sub-portion of the biologically
important area that overlaps the proposed extension. Additionally, most
of the modeled takes are for the Hawaii pelagic population of false
killer whale (see Figure 3.7-46 and Table 3.7-31). Also, as described
in more detail in Appendix K of the HSTT FEIS/OEIS, due to training and
testing needs, the expansion of this area is considered impracticable.
Comment 57: A commenter recommended extending to year-round
restrictions in the 4-Island Region Mitigation Area and the proposed
extension into the Kaiwi Channel Humpback Whale Special Reporting Area.
Response: The additional expansion requested in the comment is not
expected to reduce adverse impacts to an extent that would outweigh the
negative impacts if unit commanders were unable to conduct unit-level
training and testing, especially as they pass over Penguin Bank while
transiting between Pearl Harbor and other parts of the Study Area.
Prohibiting mid-frequency active sonar would preclude the Submarine
Command Course from meeting its objectives and leveraging the important
and unique characteristics of the 4-Islands Region, as described in
multiple sections of Appendix K (e.g., Section K.3.1.6 (4-Islands
Region and Penguin Bank Humpback Whale Reproduction Area, and
Settlement Area 2-A and 2-B)). Penguin Bank is particularly used for
shallow water submarine testing and anti-submarine warfare training
because of its large expanse of shallow bathymetry. The conditions in
Penguin Bank offer ideal bathymetric and oceanographic conditions
allowing for realistic training and testing and serve as surrogate
environments for active theater locations.
Additionally, this mitigation would further increase reporting
requirements. As discussed in Chapter 5 (Mitigation) Section 5.5.2.6
(Increasing Reporting Requirements) of the HSTT FEIS/OEIS, the Navy
developed its reporting requirements in conjunction with NMFS,
balancing the usefulness of the information to be collected with the
practicability of collecting it. An increase in reporting requirements
as a mitigation would draw the event participants' attentions away from
the complex tactical tasks they are primarily obligated to perform
(such as driving a warship), which would adversely impact personnel
safety, public health and safety, and the effectiveness of the military
readiness activity. Expanding the Mitigation Area and extending the
restrictions is not, therefore, appropriate in consideration of NMFS'
least practicable adverse impact standard.
Comment 58: A commenter recommended implementing vessel speed
restrictions within the 4-Islands Region Mitigation Area.
Response: This mitigation measure was proposed to address impacts
on humpback whales due to both ship noise and ship strikes. As
described and detailed in the Draft EIS, the Navy already implements a
number of ship-strike risk reduction measures for all vessels, in all
locations and seasons, and for all marine mammal species. The Navy
cannot implement mitigation that restricts vessel speed during training
or testing in the HSTT Study Area. Vessels must be able to maneuver
freely as required by their tactics in order for training events to be
effective. Imposition of vessel speed restrictions would interfere with
the Navy's ability to complete tests that must occur in specific
bathymetric and oceanic conditions and at specific speeds. Navy vessel
operators must test and train with vessels in such a manner that
ensures their ability to operate vessels as they would in military
missions and combat operations (including being able to react to
changing tactical situations and evaluate system capabilities).
Furthermore, testing of new platforms requires testing at the full
range of propulsion capabilities and is required to ensure the
delivered platform meets requirements. Based on an analysis of Navy
ship traffic in the HSTT Study Area between 2011 and 2015, median speed
of all Navy vessels within Hawaii is typically already low, with median
speeds between 8-16 kn (CNA, 2016). Speed restrictions in the
Cautionary Area (renamed the 4-Islands Region Mitigation Area) are
unwarranted given the movement of all social groups throughout the
islands outside the Mitigation Area, the current lack of ship strike
risk from Navy vessels in Hawaii (2010-2017), the already safe training
and testing ship speeds the Navy uses within HSTT, and existing Navy
mitigation measures, including provisions to avoid large whales by 500
yards where safe to do so. Implementing speed restrictions in the
Mitigation Area is not, therefore, appropriate in consideration of
NMFS' least practicable adverse impact standard.
Information on the response of baleen whales to vessel noise is
presented in Section 3.7.3.1.1.5 (Behavioral Reactions) and Section
3.7.3.1.5 (Impacts from Vessel Noise). Impacts, if they did occur,
would most likely be short-term masking and minor behavioral responses.
Therefore, significant impacts on humpback whale reproductive behaviors
from vessel noise associated with training activities are not expected.
Navy vessels are intentionally designed to be quieter than civilian
vessels, and ship speed reductions are not expected to reduce adverse
impacts on humpback whales due to vessel noise.
Comment 59: A commenter recommended prohibiting the use of in-water
explosives in the 4-Islands Region Mitigation Area.
Response: The Navy has agreed to implement a year-round restriction
on the use of in-water explosives that could potentially result in
takes of marine mammals during training and testing. Should national
security present a requirement explosives that could potentially result
in the take of marine mammals during training or testing, naval units
will obtain permission from the appropriate designated Command
authority prior to commencement of the activity. The Navy will provide
NMFS with advance notification and include the information (e.g., sonar
hours or explosives usage) in its annual activity reports submitted to
NMFS.
Comment 60: A commenter recommended prohibiting other sources
[[Page 66902]]
of MFAS in the 4-Islands Region Mitigation Area.
Response: NMFS reviewed Navy's assessment for the 4-Islands
Mitigation Area. This area provides a unique and irreplaceable shallow
water training capability for units to practice operations in littoral
areas that are both shallow and navigationally constrained (HSTT FEIS
Appendix K (Geographic Mitigation Assessment), Section K.3.3.1.6). The
4-Islands Region provides an environment for anti-submarine warfare
search, tracking and avoidance of opposing anti-submarine warfare
forces. The bathymetry provides unique attributes and unmatched
opportunity to train in searching for submarines in shallow water.
Littoral training allows units to continue to deploy improved sensors
or tactics in littoral waters. In the Hawaii portion of the HSTT Study
Area specifically, anti-submarine warfare training in shallow water is
vitally important to the Navy since diesel submarines typically hide in
that extremely noisy and complex marine environment (Arabian Gulf,
Strait of Malacca, Sea of Japan, and the Yellow Sea all contain water
less than 200 m deep). There is no other area in this portion of the
HSTT Study Area with the bathymetry and sound propagation analog to
seas where Navy conducts real operations that this training could
relocate to. The Navy cannot conduct realistic shallow water training
exercises without training in and around the 4-Islands Region
Mitigation Area. In addition, this area includes unique shallow water
training opportunities for unit-level training, including opportunity
to practice operations in littoral areas that are both shallow, and
navigationally constrained, and in close proximity to deeper open ocean
environments. While MFAS is used infrequently in this area, a complete
prohibition of all active sonars would impact Navy training readiness
in an area identified as important for the Navy based on its unique
bathymetry. However, the Navy recognizes the biological importance of
this area to humpback whales during the reproductive season and with
NMFS concurrence strives to limit the use of surface ship hull-mounted
MFAS during that time of year. While the Navy has been training and
testing in the area with the same basic systems for over 40 years,
there is no evidence of any adverse impacts having occurred, and there
are multiple lines of evidence demonstrating the small odontocete
population high site fidelity to the area.
Comment 61: A commenter recommended prohibiting the use of
helicopter-deployed mid-frequency active sonar in the 4-Islands Region
Mitigation Area.
Response: The commenter's request to prohibit ``air-deployed'' mid-
frequency active sonar is based on one paper (Falcone et al., 2017),
which is a Navy-funded project designed to study the behavioral
responses of a single species, Cuvier's beaked whales, to mid-frequency
active sonar. The Navy relied upon the best science that was available
to develop behavioral response functions for beaked whales and other
marine mammals in consultation with NMFS for the Draft EIS/OEIS. The
article cited in the comment (Falcone et al., 2017) was not available
at the time the Draft EIS/OEIS was published but does not change the
current FEIS/OEIS criteria or conclusions. The new information and data
presented in the article was thoroughly reviewed when it became
available and further considered in discussions with some of the
paper's authors following its first presentation in October 2017 at a
recent scientific conference. Many of the variables requiring further
analysis for beaked whales and dipping sonar impact assessment are
still being researched under continued Navy funding through 2019.
There are no beaked whale biologically important areas in the 4-
Islands Region Mitigation Area, and the Mitigation Area is generally
shallower than beaked whales' preferred habitat. Behavioral responses
of beaked whales from dipping and other sonars cannot be universally
applied to other marine mammal species. Research indicates that there
are distinct individual variations as well as strong behavioral state
considerations that influence any response or lack of response
(Goldbogen et al., 2013; Harris et al., 2017). Therefore, it is
expected that other species would have highly variable individual
responses ranging from some response to no response to any
anthropogenic sound. This variability is accounted for in the Navy's
current behavioral response curves described in the HSTT Draft EIS/OEIS
and supporting technical reports.
Furthermore, the potential effects of dipping sonar have been
rigorously accounted for in the Navy's analysis. Parameters such as
power level and propagation range for typical dipping sonar use are
factored into HSTT acoustic impact analysis along with guild specific
criteria and other modeling variables, as detailed in the HSTT DEIS/
OEIS and associated technical reports for criteria and acoustic
modeling. Further, due to lower power settings for dipping sonar,
potential impact ranges of dipping sonar are significantly lower than
surface ship sonars. For example, the HSTT average modeled range to TTS
of dipping sonar for a 1-second ping on low-frequency cetacean (i.e.,
blue whale) is 77 m, and for mid-frequency cetaceans including beaked
whales is 22 m (HSTT FEIS/OEIS Table 3.7-7). This range is easily
monitored for marine mammals by a hovering helicopter and is accounted
for in the Navy's proposed mitigation ranges for dipping sonars (200
yds. or 183 m). Limited ping time (i.e., less dipping sonar use as
compared to typical surface ship sonar use) and lower power settings
therefore would limit the impact from dipping sonar to any marine
mammal species.
This is an area of extremely low use for air-deployed mid-frequency
active sonar. Prohibiting air-deployed mid-frequency active sonar in
the Mitigation Area would not be any more protective to marine mammal
populations generally, or the Main Hawaiian Islands insular false
killer whale in particular, than currently implemented procedural
mitigation measures for air-deployed mid-frequency active sonar and is
not, therefore, appropriate in consideration of NMFS' least practicable
adverse impact standard.
Comment 62: A commenter recommended prohibiting use of low-
frequency active sonar in the 4-Islands Region Mitigation Area.
Response: The commenters suggested that ``Baleen whales are
vulnerable to the impacts of low-frequency active sonar, particularly
in calving areas where low-amplitude communication calls between
mothers and calves can be easily masked.'' As described in Chapter 3,
Section 3.7.2.3.1 (Humpback Whale (Megaptera novaeangliae), Hawaii DPS)
of the HSTT FEIS/OEIS, the best available science has demonstrated
humpback whale population increases and an estimated abundance greater
than some pre-whaling estimates. This data does not indicate any
population-level impacts from decades of ongoing Navy training and
testing in the Hawaiian Islands.
Comment 63: A commenter recommended additional mitigation areas
critical habitat for the Main Hawaiian Islands insular false killer
whale. NMFS issued the Final Rule designating critical habitat under
the ESA on July 24, 2018. A commenter stated that in light of the 2018
listing under the ESA, NMFS must protect this species from the noise
and other disturbance resulting from naval activities, including by
mitigating impacts within its critical habitat. The commenter
recommended that, at minimum, the Navy establish protective
[[Page 66903]]
Mitigation Areas in all the BIAs identified for this species by NOAA
and that NMFS should revisit and revise its Mitigation Areas and
mitigation requirements based on the final critical habitat
designation.
Response: Critical habitat includes waters from the 45 m depth
contour to the 3,200 m depth contour around the main Hawaiian Islands
from Niihau east to Hawaii (82 FR 51186). With regard to the analysis
of the identified Biologically Important Areas for the Main Hawaiian
Islands insular false killer whales, see Section K.3.3 (False Killer
Whale Small and Resident Population Area: Main Hawaiian Island Insular
stock). With regard to the identified threats to the species, see
Section 3.7.2.2.7.5 (Species-Specific Threats) and specifically the
documented incidental take by commercial fisheries (Bradford and
Forney, 2016; Oleson et al., 2010; Reeves et al., 2009; West, 2016).
NMFS has previously determined that Navy's current training and testing
activities are not expected to have fitness consequences for individual
Main Hawaiian Islands insular false killer whales and not likely to
reduce the viability of the populations those individual whales
represent.
The Navy is implementing the Hawaii Island Mitigation Area which
encompassess all of the BIA for Main Hawaiian Islands insular false
killer whales around that island, and the 4-Islands Region Mitigation
Area (which captures approximately 40 percent of the BIAs in the 4-
island area). As discussed in the Mitigation Areas in Hawaii section of
this final rule, these mitigation areas are expected to significantly
reduce impacts to this stock and its habitat.
Comment 64: Commenters recommended additional mitigation areas for
important habitat areas off Oahu, Kauai, and Niihau--the waters off
Oahu, Kauai, and Niihau include a number of important habitat areas for
a variety of species, including false killer whale critical habitat
(see above), five NOAA-identified BIAs off Oahu (false killer whale,
humpback whale, pantropical spotted dolphin, bottlenose dolphin, and
spinner dolphin) and three BIAs off Kauai and Niihau (humpback whale,
spinner dolphin, and bottlenose dolphin) (Baird et al. 2012). The
commenters assert that the agency must consider the implementation of
Mitigation Areas off Oahu, Kau`i, and Niihau. Providing mitigation
measures for select activities during even a limited season within some
important habitat areas.
Response: In the HSTT FEIS/OEIS, the Navy considered the science,
the Navy requirements, and the effectiveness of identified habitat
areas off Oahu, Kauai, and Niihau as presented in Appendix K
(Geographic Mitigation Assessment) Section K.3 (Biologically Important
Areas within the Hawaii Range Complex Portion of the HSTT Study Area).
This includes the five identified Biologically Important Areas off Oahu
(false killer whale, humpback whale, pantropical spotted dolphin,
bottlenose dolphin, and spinner dolphin) and three Biologically
Important Areas off Kauai and Niihau (humpback whale, spinner dolphin,
and bottlenose dolphin) as well as a discussion in Appendix K
(Geographic Mitigation Assessment), Section K.1.1.5 (Mitigation Areas
Currently Implemented) regarding the 4-Islands Region Mitigation Area.
Based on the Navy's analysis and as detailed in the sections
referenced above, there is no scientific basis indicating the need for
mitigation in the first place; see specifically the discussion in
Appendix K (Geographic Mitigation Assessment), Section K.2.1.2
(Biological Effectiveness Assessment) of the HSTT FEIS/OEIS. As
presented and reviewed in the HSTT FEIS/OEIS, the Navy has presented
citations to research showing that in specific contexts (such as
associated with urban noise, commercial vessel traffic, eco-tourism, or
whale watching; see Chapter 3,Section 3.7.2.1.5.2 (Commercial
Industries)) and references (Dunlop, 2016; Dyndo et al., 2015; Erbe et
al., 2014; Frisk, 2012; Gedamke et al., 2016; Hermannsen et al., 2014;
Li et al., 2015; McKenna et al., 2012; Melc[oacute]n et al., 2012;
Miksis-Olds and Nichols, 2015; Nowacek et al., 2015; Pine et al., 2016;
Pirotta et al. 2018; Williams et al., 2014c) or specifically for Hawaii
(Heenehan et al., 2016a, 2016b; Heenehan et al., 2017a, 2017b; Tyne et
al., 2014; Tyne, 2015; Tyne et al., 2015; Tyne et al., 2017), that
chronic repeated displacement and foraging disruption of populations
with residency or high site fidelity can result in population-level
effects. As also detailed in the HSTT FEIS/OEIS, the planned Navy
training and testing activities do not equate with the types of
disturbance in the citations above nor do they rise to the level of
chronic disturbance where such effects have been demonstrated. There is
no evidence to suggest there have been any population-level effects in
the waters around Oahu, Kauai, and Niihau or in the HSTT Study Area
resulting from the same training and testing activities that have been
ongoing for decades, which the commenter recommends the need to stop,
or at a minimum, be mitigated. In the waters around Oahu, Kauai, and
Niihau, documented long-term residency by individuals and the existence
of multiple small and resident populations precisely where Navy
training and testing have been occurring for decades strongly suggests
a lack of significant impact to those individuals and populations from
the continuation of Navy training and testing. Appendix K of the HSTT
FEIS/OEIS further describes the importance of these areas for Navy
training and testing and why implementation of additional mitigation
areas would be impracticable.
Comment 65: A commenter recommended additional mitigation area for
Cross Seamount, as Cross Seamount represents important foraging habitat
for a potentially rare or evolutionary distinct species of beaked
whale, a commenter strongly recommended that the HSTT EIS/OEIS assess
the designation of a year-round management area to protect the
seamount. Such a designation would have secondary benefits for a
variety of other odontocete species foraging at Cross Seamount
seasonally between November and May. NMFS should also consider habitat-
based management measures for other nearby seamounts.
Response: Analysis and consideration of Cross Seamount and ``other
nearby seamounts'' for additional geographic mitigation was provided in
Appendix K (Geographic Mitigation Assessment), Section K.7.1 (Hawaii
Public Comment Mitigation Area Assessment), including sub-sections
K.7.1.1 (General Biological Assessment of Seamounts in the Hawaii
Portion of the Study Area) and K.7.1.2 (Cross Seamount) of the HSTT
FEIS/OEIS.
As discussed in Appendix K (Geographic Mitigation Assessment),
Section 4.7.1.3 (Mitigation Assessment) of the HSTT FEIS/OEIS,
implementing new geographic mitigation measures in addition to ongoing
procedural mitigation within the vicinity of Cross Seamount would not
be effective at reducing adverse impacts on beaked whales or other
marine mammal populations. The Navy has been training and testing in
the broad ocean area around Cross Seamount with the same basic systems
for over 40 years, and there is no evidence of any adverse impacts to
marine species. Additionally, the suggested mitigation would not be
practicable to implement. The broad ocean area around Cross Seamount
and the seamounts to the north are unique in that there are no similar
broad ocean areas in the vicinity of the Hawaiian Islands that are not
otherwise
[[Page 66904]]
encumbered by commercial vessel traffic and commercial air traffic
routes. In addition, beaked whales may be more widely distributed than
currently believed. Ongoing passive acoustic efforts from NMFS and Navy
within the Pacific have documented beaked whale detections at many
locations beyond slopes and seamounts to include areas over abyssal
plains (Klinck et al. 2015, Griffiths and Barlow 2016, Rice et al.,
2018).
Comment 66: A commenter commented that the NMFS must ensure that
the activities are having the least practicable adverse impact, so it
must do a comprehensive analysis of whether the proposed mitigation
areas sufficiently protect marine mammals. NMFS must require the Navy
to implement additional, practicable measures to mitigate further the
adverse impacts of its activities. To ensure least practicable adverse
impacts, NMFS must consider additional mitigation time/area
restrictions, including but not limited to: (1) Expanded areas in
Southern California to include all of the biologically important areas
for whales; (2) add a Cuvier's beaked whale mitigation area in Southern
California to protect that small, declining population that has high
site fidelity; (3) add mitigation areas for the biologically important
areas off of Oahu and Kauai; (4) the entire Humpback National Marine
Sanctuary should be afforded protections from Navy activities because
it is an important habitat for breeding, calving and nursing; and (5)
limits on sonar and explosives should be adopted in the designated
critical habitat for the Hawaiian monk seal and false killer whale.
Response: In regards to expanded areas in Southern California to
include all of the biologically important areas for whales, the Navy
has agreed to expanded areas in SOCAL, a portion of the San Nicholas
Island BIA and the Santa Monica/Long Beach BIA are now included as part
of the San Diego Arc Mitigation Area but also named the San Nicholas
Island Mitigation Area and the Santa Monica/Long Beach Mitigation Area.
The Santa Monica Bay/Long Beach and San Nicolas Island BIA only
partially overlaps a small portion of the northern part of the SOCAL
portion of the HSTT Study Area. The Santa Monica Bay/Long Beach BIA
overlap in SOCAL is 13.9 percent. The San Nicolas Island BIA overlap in
SOCAL is 23.5 percent.
The Navy will limit surface ship sonar and not exceed 200 hours of
MFAS sensor MF1 June 1 through October 31 during unit-level training
and MTEs in the Santa Monica Bay/Long Beach BIA and San Nicolas Island
Mitigation Areas (as well as San Diego Arc Mitigation Area). The Navy
has also agreed to limit explosives. Specifically, within the San
Nicolas Island Mitigation Area, the Navy will not use explosives that
could potentially result in the take of marine mammals during mine
warfare, large-caliber gunnery, torpedo, bombing, and missile
(including 2.75'' rockets) activities during training. Within the Santa
Monica/Long Beach Mitigation Area, the Navy will not use explosives
that could potentially result in the take of marine mammals during mine
warfare, large-caliber gunnery, torpedo, bombing, and missile
(including 2.75'' rockets) activities during training and testing.
The Tanner-Cortes Bank BIA--NMFS and the Navy have discussed this
extensively, and the Navy is unable to incorporate this area into
geographic mitigation because is impracticable. Specifically, it would
not be practical for the Navy to implement and prevents the Navy from
meeting training and testing missions. As discussed in detail in
Appendix K (Geographic Mitigation Assessment) of the HSTT FEIS/OEIS,
during the Navy's practicability and biological review of the Tanner
Bank BIA, it was concluded that implementation of a mitigation area was
not practical for this species. The area in and around Tanner Banks is
a core high priority training and testing venue for SOCAL combining
unique bathymetry and existing infrastructure. This includes an
existing bottom training minefield adjacent to Tanner Banks, future
Shallow Water Training Range (SWTR West) expansion as well as proximity
to critical tactical maneuver areas to the south and the Navy's
underwater instrumented range to the northeast. Furthermore, the
general area is in or adjacent to critical Navy training that cannot
occur at other locations due to available, existing infrastructure,
operationally relevant bathymetry, sea space, proximity to San Clemente
Island and San Diego, etc.). Of all the blue whale BIAs designated, the
Tanner Banks BIA had the fewest blue whale sighting records supporting
its designation. New science since designation funded by the Navy
further highlights how infrequently Tanner Bank is used by blue whales
as compared to the rest of their movements in SOCAL. Out of 73 blue
whales tagged with satellite transmitters, only a few transits through
Tanner Banks were documented between 2014-2017. The longest cumulative
time any individual whale stayed within the boundaries of the Tanner
Banks BIA was less than one and a half days. Typical average blue whale
daily movement along the U.S. West Coast is often up to 13-27 nautical
miles a day (Oregon State University, unpublished data). Most blue
whale area restricted foraging occurred around the northern Channel
Islands, north of and outside of the HSTT SOCAL Study Area.
The feeding areas as recommended by the commenter north of Los
Angeles for humpbacks (Santa Barbara Channel-San Miguel BIA and Morro
Bay to Pt Sal) and blue whales (Santa Barbara Channel to San Miguel
BIA, Pt Conception/Arguello to Pt Sal) are outside of the HSTT Study
Area; therefore are not applicable for inclusion.
In regard to adding a Cuvier's beaked whale mitigation area in
Southern California to protect that small, declining population that
has high site fidelity, NMFS is assuming the commenter is referring to
the area west of San Clemente Island as the comment letter did not
specify an exact location. The beaked whale species detected most
frequently in Southern California is Cuvier's beaked whale. Cuvier's
beaked whales are widely distributed within Southern California and
across the Pacific with almost all suitable deep water habitat >800 m
conceivably containing Cuvier's beaked whales. In new unpublished Navy
funded data, beaked whales have even been detected over deep water,
open abyssal plains (>14,000 feet). Only limited population vital rates
exist for beaked whales, covering numbers of animals, populations vs.
subpopulations determination, and residency time for individual
animals. While Cuvier's beaked whales have been detected north and west
of Tanner and Cortes Banks, as noted above this species is also
detected in most all Southern California locations 800 m in depth. The
Navy's Marine Mammal Monitoring on Navy Ranges (M3R) program has
documented continual Cuvier's beaked whale presence on SOAR over 8-
years from 2010-2017 with slight abundance increases through 2017
(DiMarzio et al., 2018.)
Navy-funded research on Cuvier's beaked whales within the Southern
California (SOCAL) Range Complex began in 2006. In 2008, researchers
began deploying satellite tags as a part of this research. To date, 27
Low- Impact Minimally-Percutaneous External-electronics Transmitting
(LIMPET) tags have been deployed within the complex. Twenty-five of
those whales were tagged within the San Nicolas Basin and two were
tagged in the Catalina Basin. Average transmission duration was 36.6
days (sd
[[Page 66905]]
= 29.8), with the longest transmitting for 121.3 days. Movement data
suggest that Cuvier's beaked whales have a high degree of site-fidelity
to the Southern California Range Complex, and the San Nicolas basin in
particular. Overall, there were 3,207 filtered location estimates from
the 27 tagged whales, 91 percent of which were within the SoCal Range
Complex. 54 percent of all location estimates were within the San
Nicolas Basin, with twelve tagged whales spending more than 80 percent
of their transmission duration within the basin. The two whales tagged
in the Catalina Basin never entered the San Nicolas Basin. Only three
whales tagged in the San Nicolas Basin crossed into the Catalina Basin
(1.3 percent of all locations); two of those whales had just one
Catalina Basin location each, though the remaining whale had 28 percent
of its locations there. Five whales tagged in the San Nicolas Basin
moved into the Santa Cruz Basin for anywhere from 1-62 percent of their
time (6 percent of all locations). In contrast, 20 of 25 whales tagged
in the San Nicolas Basin moved south of the basin at some point. Of
these 20 whales, most remained within either Tanner Canyon or the San
Clemente Basin immediately to the south, but one traveled north to near
San Miguel Island and four traveled south towards Guadalupe Island.
Three of these whales have not been documented in the San Nicolas basin
since, though to date at least six whales tagged in the San Nicolas
Basin have been re-sighted there a year or more after the deployment.
Additionally, one of the whales that was south of San Nicolas when the
tag stopped transmitting has since been sighted three times since.
Given that there is the uncertainty of current residence of
Cuvier's beaked whales in the areas north and west of SOAR, the fact
that general occurrence of beaked whales in Southern California may not
necessarily equate to factors typically associated with biologically
important areas (i.e., one area not more important than another), and
consideration of the importance of Navy training and testing in the
areas around SOAR and Tanner and Cortes Banks as discussed in Appendix
K (Geographic Mitigation Assessment), i.e., the impracticability of
additional area mitigation in this area, additional geographic
mitigation to create a ``refuge'' in the recommended area is not
scientifically supported or warranted.
In regard to the comment on the entire Humpback Whale National
Marine Sanctuary should be afforded protections from Navy activities
because it is an important habitat for breeding, calving and nursing
the Humpback National Marine Sanctuary largely overlaps both the Hawaii
Island Mitigation Area as well as the 4-Islands Region Mitigation Area.
In the Hawaii Island Mitigation Area (year-round), the Navy will not
conduct more than 300 hours of MF1 surface ship hull-mounted mid-
frequency active sonar or 20 hours of MF4 dipping sonar, or use
explosives that could potentially result in takes of marine mammals
during training and testing. In the 4-Islands Region Mitigation Area
(November 15-April 15 for active sonar; year-round for explosives), the
Navy will not use MF1 surface ship hull-mounted mid-frequency active
sonar or explosives that could potentially result in takes of marine
mammals during training and testing. This seasonal limitation is
specifically during important breeding, calving, and nursing, times/
habitat for humpback whales and was expanded for humpback whales as the
previous season for this mitigation area was December 15-April 15).
There are areas of the Humpback Whale National Marine Sanctuary
around the islands of Niihau, Kauai, Oahu, and west of Molokai (Penguin
Bank) that are outside of the Navy's mitigation areas. However, none of
the Navy's training and testing areas for explosives around Kauai and
Niihau are within the Hawaiian Islands Humpback Whale National Marine
Sanctuary. There may be limited sonar use as units transit to/from PMRF
ranges.
Part of the Humpback Whale National Marine Sanctuary, west of the
island of Molokai, Penguin Bank, is not included in the 4-Islands
Region Mitigation Area. Penguin Bank particularly is used for shallow
water submarine testing and anti-submarine warfare training because of
its large expanse of shallow bathymetry. While submarines do not
typically use mid-frequency active sonar, relying primarily on passive
sonar (listening mode) to avoid detection from adversaries, submarines
are required to train in counter detection tactics, techniques and
procedures against threat surface vessels, airborne anti-submarine
warfare units and other threat submarines using mid-frequency active
sonar as part of both their perspective Commanding Officers
qualification course and pre-deployment certification. The ability for
surface vessels and air assets to simulate opposing forces, using mid-
frequency active sonar when training with submarines, is critical to
submarine crew training for deployed and combat operations. Surface
ships and aircraft mimicking opposition forces present submarines with
a realistic and complicated acoustic and tactical environment. The Navy
expects real-world adversaries to target our submarines with active
sonar. Without active sonar from opposition forces submarines do not
get a realistic picture regarding if they successfully evaded
detection. Surface warfare training is designed to support unit-level
training requirements and group cross-platform events in 28 mission
areas for surface ship certification prior to deployment.
Additionally, the Navy will implement the Humpback Whale Special
Reporting Area (December 15 through April 15) is comprised of
additional areas of high humpback whale densities that overlap the
Humpback Whale National Marine Sanctuary. This reporting is included in
the exercise and monitoring reports that are an ongoing Navy
requirement and are submitted to NMFS annually. Special reporting data,
along with all other reporting requirements, are considered during
adaptive management to determine if additional mitigation may be
required. The Navy currently reports to NMFS the total hours (from
December 15 through April 15) of all hull-mounted mid-frequency active
sonar usage occurring in the Humpback Whale Special Reporting Area,
plus a 5 km buffer, but not including the Pacific Missile Range
Facility. The Navy will continue this reporting for the Humpback Whale
Special Reporting Area.
In regard to limits on sonar and explosives should be adopted in
the ESA-designated critical habitat for the Hawaiian monk seal and
false killer whale, the Navy will cap MFAS for the entire false killer
whale BIA adjacent to the island of Hawaii and a portion of the false
killer whale BIA north of Maui and Molokai as follows. The Navy already
will to limit explosive use in the entire false killer whale BIA
adjacent to the island of Hawaii. The Navy will now add year-round
limitation on explosives to the 4-Islands Region Mitigation Area, which
includes a portion of the false killer whale BIA north of Maui and
Molokai. For the Hawaii Island Mitigation Area (year-round): The Navy
will not conduct more than 300 hours of surface ship hull-mounted MFAS
sonar MF1 (MF1) or 20 hours of MFAS dipping sonar MF4 (MF4), or use
explosives during training and testing year-round. For the 4-Islands
Region Mitigation Area (November 15-April 15 for active sonar, year-
round for explosives): The Navy will not use surface ship hull-mounted
MFAS sonar MF1 from November 15-April 15 and explosive year-round
during training or
[[Page 66906]]
testing activities. The remaining false killer whale BIA overlaps with
areas (e.g., Kaiwi Channel) where additional mitigations were found to
be impractical.
In regard to limits on sonar and explosives in ESA-designated
critical habitat for Hawaiian monk seal, the Navy's training and
testing activities do occur in a portion of the ESA-designated critical
habitat for Hawaiian monk seals, which is of specific importance to the
species. However, monk seals in the main Hawaiian Islands have
increased while the Navy has continued its activities, even though the
Hawaiian monk seal overall population trend has been on a decline from
2004 through 2013, with the total number of Hawaiian monk seals
decreasing by 3.4 percent per year (Carretta et al., 2017). While the
decline has been driven by the population segment in the northwestern
Hawaiian Islands, the number of documented sightings and annual births
in the main Hawaiian Islands has increased since the mid-1990s (Baker,
2004; Baker et al., 2016). In the main Hawaiian Islands, the estimated
population growth rate is 6.5 percent per year (Baker et al., 2011;
Carretta et al., 2017). Of note, in the 2013 HRC Monitoring Report,
tagged monk seals did not show any behavioral changes during periods of
MFAS.
The Hawaii Island Mitigation Area overlaps all of their critical
habitat around the Island of Hawaii (as well as the southern end of
Maui) and, by not using explosives or the most impactful sonar sources
in this, thereby reduces the likelihood that take might impact
reproduction or survival by interfering with important feeding or
resting behaviors (potentially having adverse impacts on energy
budgets) or separating mothers and pups in times when pups are more
susceptible to predation and less able to feed or otherwise take care
of themselves. The 4-Islands Mitigation Area overlaps with ESA-
designated critical habitat around Maui, Lanai, and Molokai.
Comment 67: A commenter commented that in the proposed rule, NMFS
estimates 588 takes annually will cause multiple instances of exposure
to insular false killer whales, taking 400 percent of the population.
As the potential biological removal is 0.18 animals, the loss of a
single individual, or an impairment to its health and fitness, could
place the species on an extinction trajectory. NMFS must consider
additional mitigation in the designated critical habitat, as well as
excluded areas, to ensure a negligible impact on false killer whales.
Response: The commenter is conflating behavioral take with
mortality take addressed in PBR. There are no insular false killer
whale mortality takes modeled, anticipated, or authorized. 400 percent
of the population would mean that all animals would be behaviorally
harassed an average of 4 times per year, or once per season. The short
term biological reaction of an animal for periods of minutes to hours a
few times a year would not have any fitness impacts to the individual
let alone any population level impacts. NMFS confirms that these
impacts are negligible. Additionally, much of the Navy's mitigations on
Hawaii and the 4 island region encompass areas that overlap with high
use insular false killer whale habitat and thus already mitigate
impacts. From the Navy consultation with NMFS under the ESA for insular
false killer whale critical habitat, less than 12 percent of modeled
takes would take place in or near insular false killer whale critical
habitat. These takes as explained previously would be transitory
(short-duration), and spread out in time and space.''
Comment 68: A commenter recommended establishing stand-off
distances around the Navy's mitigation areas to the greatest extent
practicable, allowing for variability in size given the location of the
area, the type of operation at issue, and the species of concern.
Response: Mitigation areas are typically developed in consideration
of both the area that is being protected and the distance from the
stressor in question that is appropriate to maintain to ensure the
protection. Sometimes this results in the identification of the area
plus a buffer, and sometimes both the protected area and the buffer are
considered together in the designation of the edge of the area. We note
that the edges of a protected area are typically of less importance to
a protected stock or behavior, since important areas often have a
density gradient that lessens towards the edge. Also, while a buffer of
a certain size may be ideal to alleviate all impacts of concern, a
lessened buffer does not mean that the protective value is
significantly reduced, as the core of the area is still protected.
Also, one should not assume that activities are constantly occurring in
the area immediately adjacent to the protected area.
These issues were considered here, and the Navy has indicated that
the mitigation identified in Chapter 5 (Mitigation), Section 5.4
(Mitigation Areas to be Implemented) of the HSTT FEIS/OEIS represents
the maximum mitigation within mitigation areas and the maximum size of
mitigation areas that are practicable to implement under the Proposed
Action. The Navy has communicated (and NMFS concurs with the
assessment) that implementing additional mitigation (e.g., stand-off
distances that would extend the size of the mitigation areas) beyond
what is described in Chapter 5 (Mitigation), Section 5.4 (Mitigation
Areas to be Implemented) of the HSTT FEIS/OEIS would be impracticable
due to implications for safety (the ability to avoid potential
hazards), sustainability (based on the amount and type of resources
available, such as funding, personnel, and equipment)), and the Navy's
ability to continue meeting its Title 10 requirements.
Additional Mitigation Research
Comment 69: A commenter recommended NMFS consider additional
mitigation measures to prescribe or research including: (1) Research
into sonar signal modifications; (2) mitigation and research on Navy
ship speeds (the commenter recommended that the agency require the Navy
to collect and report data on ship speed as part of the EIS process);
and (3) compensatory mitigation for the adverse impacts of the
permitted activity on marine mammals and their habitat that cannot be
prevented or mitigated.
Response: NMFS consulted with the Navy regarding potential research
into additional mitigation measures and discussion is included below.
1. Research into sonar signal modification--Sonar signals are
designed explicitly to provide optimum performance at detecting
underwater objects (e.g., submarines) in a variety of acoustic
environments. The Navy acknowledges that there is very limited data,
and some suggest that up or down sweeps of the sonar signal may result
in different animal reactions; however, this is a very small data
sample, and this science requires further development. If future
studies indicate this could be an effective approach, then NMFS and the
Navy will investigate the feasibility and practicability to modify
signals, based on tactical considerations and cost, to determine how it
will affect the sonar's performance.
2. Mitigation and research on Navy ship speeds inclusive of Navy
collecting and reporting data on ship speed as part of the EIS--The
Navy conducted an operational analysis of potential mitigation areas
throughout the entire Study Area to consider a wide range of mitigation
options, including but not limited to vessel speed restrictions. As
[[Page 66907]]
discussed in Chapter 3, Section 3.0.3.3.4.1 (Vessels and In-Water
Devices) of the HSTT FEIS/OEIS, Navy ships transit at speeds that are
optimal for fuel conservation or to meet operational requirements.
Operational input indicated that implementing additional vessel speed
restrictions beyond what is identified in Chapter 5 (Mitigation),
Section 5.4 (Mitigation Areas to be Implemented) of the HSTT FEIS/OEIS
would be impracticable to implement due to implications for safety and
sustainability. In its assessment of potential mitigation, the Navy
considered implementing additional vessel speed restrictions (e.g.,
expanding the 10 kn restriction to other activities). The Navy
determined that implementing additional vessel speed restrictions
beyond what is described in Chapter 5 (Mitigation), Section 5.5.2.2
(Restricting Vessel Speed) of the HSTT FEIS/OEIS would be impracticable
due to implications for safety (the ability to avoid potential
hazards), sustainability (maintain readiness), and the Navy's ability
to continue meeting its Title 10 requirements to successfully
accomplish military readiness objectives. Additionally, as described in
Chapter 5 (Mitigation), Section 5.5.2.2 (Restricting Vessel Speed) of
the HSTT FEIS/OEIS, any additional vessel speed restrictions would
prevent vessel operators from gaining skill proficiency, would prevent
the Navy from properly testing vessel capabilities, or would increase
the time on station during training or testing activities as required
to achieve skill proficiency or properly test vessel capabilities,
which would significantly increase fuel consumption. As discussed in
Chapter 5 (Mitigation), Section 5.3.4.1 (Vessel Movement) of the HSTT
FEIS/OEIS, the Navy implements mitigation to avoid vessel strikes
throughout the Study Area. As directed by the Chief of Naval Operations
Instruction (OPNAVINST) 5090.1D, Environmental Readiness Program, Navy
vessels report all marine mammal incidents worldwide, including ship
speed. Therefore, the data required for ship strike analysis discussed
in the comment is already being collected. Any additional data
collection required would create an unnecessary and impracticable
administrative burden on the Navy.
3. Compensatory mitigation--For years, the Navy has implemented a
very broad and comprehensive range of measures to mitigate potential
impacts to marine mammals from military readiness activities. As the
HSTT FEIS/OEIS documents in Chapter 5 (Mitigation), the Navy is
proposing to expand these measures further where practicable. Aside
from direct mitigation, as noted by the commenter, the Navy engages in
an extensive spectrum of other activities that greatly benefit marine
species in a more general manner that is not necessarily tied to just
military readiness activities. As noted in Chapter 3, Section 3.0.1.1
(Marine Species Monitoring and Research Programs) of the HSTT FEIS/
OEIS, the Navy provides extensive investment for research programs in
basic and applied research. The U.S. Navy is one of the largest sources
of funding for marine mammal research in the world, which has greatly
enhanced the scientific community's understanding of marine species
much more generally. The Navy's support and marine mammal research
includes: Marine mammal detection, including the development and
testing of new autonomous hardware platforms and signal processing
algorithms for detection, classification, and localization of marine
mammals; improvements in density information and development of
abundance models of marine mammals; and advancements in the
understanding and characterization of the behavioral, physiological
(hearing and stress response), and potentially population-level
consequences of sound exposure on marine life. Compensatory mitigation
is not required to be imposed upon Federal agencies under the MMPA.
Importantly, the commenter did not recommend any specific measure(s),
rendering it impossible to conduct any meaningful evaluation of its
recommendation. Finally, many of the methods of compensatory mitigation
that have proven successful in terrestrial settings (purchasing or
preserving land with important habitat, improving habitat through
plantings, etc.) are not applicable in a marine setting with such far-
ranging species. Thus, any presumed conservation value from such an
idea would be purely speculative at this time.
Comment 70: A commenter recommended that given the paucity of
information on marine mammal habitat currently available for the HSTT
Study Area, that efforts be undertaken in an iterative manner by NMFS,
and the Navy, to identify additional important habitat areas across the
HSTT Study Area, using the full range of data and information available
to the agencies (e.g., habitat-based density models, NOAA-recognized
BIAs, survey data, oceanographic and other environmental data, etc.).
Response: NMFS and the Navy used the best available scientific
information (e.g., SARs and numerous study reports from Navy-funded
monitoring and research in the specific geographic region) in assessing
density, distribution, and other information regarding marine mammal
use of habitats in the HSTT Study Area. In addition, NMFS consulted
LaBrecque et al. (2015), which provides a specific, detailed assessment
of known BIAs, which may be region-, species-, and/or time-specific,
include reproductive areas, feeding areas, migratory corridors, and
areas in which small and resident populations are concentrated. While
the science of marine mammal occurrence, distribution, and density
resides as a core NMFS mission, the Navy does provide extensive support
to the NMFS mission via ongoing HSTT specific monitoring as detailed in
this final rule. Also included are direct Navy funding support to NMFS
for programmatic marine mammal surveys in Hawaii and the U.S. West
Coast, and spatial habitat model improvements.''
Comment 71: A commenter recommended integration of important
habitat areas to improve resolution of operations. The delineation of
BIAs by NOAA, the updates made by the Navy to its predictive habitat
models, and evidence of additional important habitat areas within the
HSTT 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. A commenter
offered the following thoughts for consideration.
They state 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
derived from the NAEM 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 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. While
the proposed rule, in assessing environmental impacts on marine
mammals, breaks down estimated impacts by general region (i.e., HRC and
SOCAL), the resolution is seldom greater than range complex or
[[Page 66908]]
homeport and is not specifically focused on areas of higher biological
importance. Current and ongoing efforts to identify important habitat
areas for marine mammals should be used by NMFS and by the Navy as a
guide to the most appropriate scale(s) for the analysis of operations.
Response: In their take request and effects analysis provided to
NMFS, the Navy considered historic use (number and nature of training
and testing activities) and locational information of training and
testing activities when developing modelling boxes. The timing of
training cycles and testing needs varies based on deployment
requirements to meet current and emerging threats. Due to the
variability, the Navy's description of its specified activities is
structured to provide flexibility in training and testing locations,
timing, and number. In addition, information regarding the exact
location of sonar usage is classified. Due to the variety of factors,
many of which influence locations that cannot be predicted in advance
(e.g., weather), the analysis is completed at a scale that is necessary
to allow for flexibility. The purpose of the Navy's quantitative
acoustic analysis is to provide the best estimate of impact/take to
marine mammals and ESA listed species for the regulatory and ESA
section 7 consultation analyses. Specifically, the analysis must take
into account multiple Navy training and testing activities over large
areas of the ocean for multiple years; therefore, analyzing activities
in multiple locations over multiple seasons produces the best estimate
of impacts/take to inform the HSTT FEIS/OEIS and regulators. Also, the
scale at which spatially explicit marine mammal density models are
structured is determined by the data collection method and the
environmental variables that are used to build the model. Therefore,
altogether, given the variables that determine when and where the Navy
trains and tests, as well as the resolution of the density data, the
analysis of potential impacts is scaled to the level that the data
fidelity will support. NMFS has worked with the Navy over the years to
increase the spatio-temporal specificity of the descriptions of
activities planned in or near areas of biological importance, when
possible (e.g., in BIAs or Sanctuaries, where possible), and NMFS is
confident that the granularity of information provided sufficiently
allows for an accurate assessment of both the impacts of the Navy's
activities on marine mammal populations and the protective measures
evaluated to mitigate those impacts.
Monitoring Recommendations
Comment 72: A commenter recommended that NMFS require that the Navy
continue to conduct long-term monitoring with the aim to provide
baseline information on occurrence, distribution, and population
structure of marine mammal species and stocks, and baseline information
upon which the extent of exposure to disturbance from training and
testing activities at the individual, and ultimately, population level-
impacts, and the effectiveness of mitigation measures, can be
evaluated. The commenter recommended individual-level behavioral-
response studies, such as focal follows and tagging using DTAGs,
carried out before, during, and after Navy training and testing
activities. The commenter recommended prioritizing DTAG studies that
further characterize the suite of vocalizations related to social
interactions. The commenter recommends the use of unmanned aerial
vehicles. The commenter recommended that NMFS require the Navy to use
these technologies for assessing marine mammal behavior before, during,
and after Navy training and testings (e.g., swim speed and direction,
group cohesion). Additionally, the commenter recommended studies into
how these technologies can be used to assess body condition be
supported as this can provide an important indication of energy budget
and health, which can inform the assessment of population-level
impacts.
Response: Broadly speaking, 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 Navy's MMPA rule. The
process NMFS and the Navy have developed allows for comprehensive and
timely input from the Navy and other stakeholders that is based on
rigorous reporting out from the Navy and the researchers doing the
work. Further, the Navy is pursuing many of the topics that the
commenter identifies, either through the Navy monitoring required under
the MMPA and ESA, or through Navy-funded research programs (ONR and
LMR). We are confident that the monitoring conducted by the Navy
satisfies the requirements of the MMPA.
The Navy established the Strategic Planning Process under the
marine species monitoring program to help structure the evaluation and
prioritization of projects for funding. Chapter 5 (Mitigation), Section
5.1.2.2.1.3 (Strategic Planning Process) of the HSTT FEIS/OEIS provides
a brief overview of the Strategic Planning Process. More detail,
including the current intermediate scientific objectives, is available
on the monitoring portal 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 steering committee
evaluate how well a potential project would address the primary
objectives of the monitoring program. NMFS has opportunities to provide
input regarding the Navy's intermediate scientific objectives as well
as providing 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/.
Details on 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. 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.
(1) Individual-level behavioral-response studies--In addition to
the Navy's marine species monitoring program investments for
individual-level behavioral-response studies, the Office of Naval
Research Marine Mammals and Biology program and the Navy's Living
Marine Resources program continue to heavily invest in this topic. For
example, the following studies are currently being funded:
The Southern California Behavioral Response Study
(Principal Investigators: John Calambokidis and Brandon Southall)
Cuvier's Beaked Whale and Fin Whale Behavior During
Military Sonar Operations: Using Medium-term Tag Technology to
Develop Empirical Risk Functions (Principal Investigators: Greg
Schorr and Erin Falcone)
3S3-Behavioral responses of sperm whales to naval sonar
(Principal Investigators: Petter Kvadsheim and Frans-Peter Lam)
Measuring the effect of range on the behavioral response of
marine mammals through the use of Navy sonar (Principal
Investigators: Stephanie Watwood and Greg Schorr)
[[Page 66909]]
Behavioral response evaluations employing robust baselines
and actual Navy training (BREVE) (Principal Investigators: Steve
Martin, Tyler Helble, Len Thomas)
Integrating remote sensing methods to measure baseline
behavior and responses of social delphinids to Navy sonar (Principal
Investigators: Brandon Southall, John Calambokidis, John Durban).
(2) DTAGS to characterize social communication between individuals
of a species or stock, including mothers and calves. Furthermore, DTAGs
are just one example of animal movement and acoustics tag. From the
Navy's Office of Naval Research and Living Marine Resource 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. Examples of these projects include:
Southern California Behavioral Response Study (Principal
Investigators: John Calambokidis and Brandon Southall)
Tagging and Tracking of Endangered North Atlantic Right
Whales in Florida Waters (Principal Investigators: Doug Nowacek and
Susan Parks). This project involves the use of DTAGs, and data
regarding the tagged individual and group are collected in
association with the tagging event. In addition to the vocalization
data that is being collected on the DTAGs, data is collected on
individual and group behaviors that are observed, including between
mother/calf pairs when applicable. The Navy will continue to collect
this type of data when possible.
Integrating remote sensing methods to measure baseline
behavior and responses of social delphinids to Navy sonar (Principal
Investigators: Brandon Southall, John Calambokidis, John Durban)
Acoustic Behavior of North Atlantic Right Whale (Eubalaena
glacialis) Mother-Calf Pairs (Principal Investigators: Susan E.
Parks and Sofie Van Parijs). The long-term goal of this project is
to quantify the behavior of mother-calf pairs from the North
Atlantic right whale to determine: a) why mothers and calves are
more susceptible to collisions with vessels and b) the vocal
behavior of this critical life stage to assess the effectiveness of
passive acoustic monitoring to detect mother-calf pairs in important
habitat areas (see https://www.onr.navy.mil/reports/FY15/mbparks.pdf).
Social Ecology and Group Cohesion in Pilot Whales and Their
Responses to Playback of Anthropogenic and Natural Sounds (Principal
Investigator: Frants H. Jensen). This project investigates the
social ecology and cohesion of long-finned pilot whales as part of a
broad multi-investigator research program that seeks to understand
how cetaceans are affected by mid-frequency sonar and other sources
of anthropogenic noise (see https://www.onr.navy.mil/reports/FY15/mbjensen.pdf).
(3) Unmanned Aerial Vehicles to assess marine mammal behavior
before, during, and after Navy training and testing activities (e.g.,
swim speed and direction, group cohesion)--Studies that use unmanned
aerial vehicles to assess marine mammal behaviors and body condition
are being funded by the Office of Naval Research Marine Mammals and
Biology program. Although the technology shows promise, the field
limitations associated with the use of this technology has hindered the
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 (Principal Investigators: Brandon
Southall, John Calambokidis, and John Durban).
(4) 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 Office of
Naval Research 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, relevant
data that is 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. General population level trend analysis is
conducted by NMFS through its stock assessment reports and regulatory
determinations. The Navy's analysis of effects to populations (species
and stocks) of all potentially exposed marine species, including marine
mammals and sea turtles, is based on the best available science as
discussed in Sections 3.7 (Marine Mammals) and 3.8 (Reptiles) of the
HSTT FEIS/OEIS. PCoD models, similar to many fisheries stock assessment
models, once developed will be powerful analytical tools when mature.
However, currently they are dependent on too many unknown factors for
these types of models to produce a reliable answer. As discussed in the
Monitoring section of the final rule, the Navy's marine species
monitoring program typically supports 10-15 projects in the Atlantic at
any given time. Current projects cover a range of species and topics
from collecting baseline data on occurrence and distribution, to
tracking whales and sea turtles, 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/atlantic/current-projects/.
A list of the monitoring studies that the Navy is currently planning
under this rule are listed at the bottom of the Monitoring section of
this final rule.
Negligible Impact Determination
General
Comment 73: Commenters commented that NMFS' analytical approach for
negligible impact determination is not transparent and that the methods
and resulting data cannot be substantiated with the information
provided. The Commission stated that in general, NMFS has based
negligible impact determinations associated with incidental take
authorizations on abundance estimates provided either in its Stock
Assessment Reports (SARs) or other more recent published literature.
For the HSTT proposed rule, NMFS used abundance estimates as determined
by the Navy's underlying density estimates rather than abundance
estimates from either the SARs or published literature. NMFS did also
not specify how it determined the actual abundance given that many of
the densities differ on orders of kilometers. Interpolation or
smoothing, and potentially extrapolation, of data likely would be
necessary to achieve NMFS' intended goal--it is unclear whether any
such methods were implemented. In addition, it is unclear whether NMFS
estimated the abundances in the same manner beyond the U.S. EEZ as it
did within the U.S. EEZ for HRC and why it did not compare takes within
the U.S. EEZ and beyond the U.S. EEZ for
[[Page 66910]]
SOCAL, given that a larger proportion of the Navy's SOCAL action area
is beyond the U.S. EEZ than HRC. Furthermore, NMFS did not specify how
it determined the proportion of total takes that would occur beyond the
U.S. EEZ. Moreover, the `instances' of the specific types of taking
(i.e., mortality, Level A and B harassment) do not match the total
takes `inside and outside the EEZ' in Tables 69-81 (where applicable)
or those take estimates in Tables 41-42 and 67-68. It also appears the
`instances' of take columns were based on only those takes in the U.S.
EEZ for HRC rather than the area within and beyond the U.S. EEZ. It
further is unclear why takes were not apportioned within and beyond the
U.S. EEZ for SOCAL. Given that the negligible impact determination is
based on the total taking in the entire study area, NMFS should have
partitioned the takes in the `instances' of take columns in Tables 69-
81 for all activities that occur within and beyond the U.S. EEZ. One
commenter further asserts that any ``small numbers'' determination that
relies on abundance estimates derived simplistically from modeled
densities is both arbitrary and capricious. The commenters assert that
NMFS should, at least for data rich species, derive its absolute
abundance estimates from NMFS' SARs or more recently published
literature.
Response: NMFS' Analysis and Negligible Impact Determination
section has been updated and expanded in the final rule to clarify the
issues the Commenters raise here (as well as others). Specifically,
though, NMFS uses both the Navy-calculated abundance (based on the
Navy-calculated densities described in detail in the Estimated Take of
Marine Mammal section) and the SARs abundances, where appropriate, in
the negligible impact analysis--noting that the nature of the overlap
of the Navy Study Area with the U.S. EEZ is different in Hawaii versus
SOCAL, supporting different analytical comparisons.
NMFS acknowledges that there were a few small errors in the take
numbers in the proposed rule; however, they have been corrected (i.e.,
the take totals in Tables 41 and 42 for a given stock now equal the
``in and outside the U.S. EEZ'' take totals in Tables X-Y) and the
minor changes do not affect the analysis or determinations in the rule.
Also, the Commenters are incorrect that the instances of take for
HRC do not reflect the take both within and outside the U.S. EEZ. They
do. Last, one commenter mentions the agency making a ``small numbers''
determination, but such a determination is not applicable in the
context of military readiness activities.
Comment 74: A commenter commented that the activities proposed by
the Navy include high-intensity noise pollution, vessel traffic,
explosions, pile driving, and more at a massive scale. According to the
commenter, NMFS has underestimated the amount of take and the adverse
impact that it will have on marine mammals and their habitat.
Response: NMFS has provided extensive information demonstrating
that the best available science has been used to estimate the amount of
take, and further to analyze the impacts that all of these takes
combined will have on the affected species and stocks. As described in
the Analysis and Negligible Impact Determination section, this
information and our associated analyses support the negligible impact
determinations necessary to issue these regulations.
Comment 75: A commenter commented that blue whales exposed to mid-
frequency sonar (with received levels of 110 to 120 dB re 1 [mu]Pa) are
less likely to produce calls associated with feeding behavior. They
cite the Goldbogen et al. (2013) study (and a subsequent study) as
extremely concerning because of the potential impacts of sonar on the
essential life functions of blue whales as it found that sonar can
disrupt feeding and displace blue whales from high-quality prey
patches, significantly impacting their foraging ecology, individual
fitness, and population health. They also state that mid-frequency
sonar has been associated with several cases of blue whale stranding
events and that low-frequency anthropogenic noise can mask calling
behavior, reduce communication range, and damage hearing. These impacts
from sonar on blue whales suggest that the activities' impacts would
have long-term, non-negligible impacts on the blue whale population.
Response: As described in this final rule in the Analysis and
Negligible Impact Determination section, NMFS has fully considered the
effects that exposure to sonar can have on blue whales, including
impacts on calls and feeding and those outlined in the Goldbogen study.
However, as discussed, any individual blue whale is not expected to be
exposed to sonar and taken on more than several days per year. Thus,
while vocalizations may be impacted or feeding behaviors temporarily
disrupted, this small scale of impacts is not expected to affect
reproductive success or survival of any individuals, especially given
the limitations on sonar and explosive use within blue whale BIAs. Of
additional note, while the blue whale behavioral response study (BRS)
in Southern California documented some foraging responses by blue
whales to simulated Navy sonar, any response was highly variable by
individual and context of the exposure. There were, for instance, some
individual blue whales that did not respond. Recent Navy-funded blue
whale tracking has documented wide ranging movements through Navy areas
such that any one area is not used extensively for foraging. More long-
term blue whale residency occurs north of and outside of the HSTT Study
Area. Further, we disagree with the assertion that MFAS has been
causally associated with blue whale strandings. This topic was
discussed at length in the proposed rule and there is no data causally
linking MFAS use with blue whale strandings.
Comment 76: A commenter commented that NMFS cannot consider the
additional mortality/serious injury, including the 0.2 in the proposed
authorization for ship strike for blue whales, to have a negligible
impact determination for this stock. They also state that counts of
mortality/serious injury do not account for the additional takes
proposed to be authorized that cumulatively can have population level
impacts from auditory injury and behavioral disturbance. Similarly, the
commenter commented that NMFS cannot consider the proposed
authorization for 0.4 annual mortality/serious injury to have a
negligible impact on the CA/OR/WA stock of humpback whales because take
is already exceeding the potential biological removal, and especially
concerning is any take authorized for the critically endangered Central
America population that would have significant adverse population
impacts.
Response: As described in detail in the Estimated Take of Marine
Mammals section, the Navy and NMFS have revisited and re-analyzed the
Navy's initial request for takes by mortality of blue and humpback
whales from vessel strike and determined that only 1 strike of either
would be anticipated over the course of 5 years, and therefore
authorized the lesser amount. Further, NMFS has expanded and refined
the discussion of mortality take, PBR, and our negligible impact
finding in the Serious Injury and Mortality sub-section of the Analysis
and Negligible Impact Determination section and do not repeat it here.
Comment 77: A commenter commented that the estimated
[[Page 66911]]
population size for the Hawaii stock of sei whales is only 178 animals,
and the potential biological removal is 0.2 whales per year. According
to the Commenters, NMFS admits that the mortality for the Hawaii stock
of sei whales is above potential biological removal. The commenter
asserted that the conclusion that the action will have a negligible
impact on this stock is arbitrary and capricious.
Response: As described in detail in the Estimated Take of Marine
Mammals section, the Navy and NMFS revisited and re-analyzed the Navy's
initial request for the take of a sei whale from vessel strike and
determined that this take is unlikely to occur and, therefore, it is
not authorized.
Comment 78: A commenter commented that any take of Hawaiian monk
seal by the proposed activities will have a non-negligible impact given
the precarious status of this species.
Response: NMFS' rationale for finding that the Navy's activity will
have a negligible impact on monk seals is included in the Pinniped
subsection of the Analysis and Negligible Impact Determination section
and is not re-printed here. Nonetheless we reiterate that no mortality
or injury due to tissue damage is anticipated or authorized, only one
instance of PTS is estimated and authorized, and no individual monk
seal is expected to be exposed to stressors that would result in take
more than a few days a year. Further, the Hawaii Island and 4-Island
mitigation areas provide significant protection of monk seal critical
habitat in the Main Hawaiian Islands, reducing impacts form sonar and
explosives around a large portion of pupping beaches and foraging
habitat, as described in the Mitigation Measures section.
Cumulative and Aggregate Effects
Comment 79: One commenter asserted that NMFS has not apparently
considered the impact of Navy activities on a population basis for many
of the marine mammal populations within the HSTT Study Area. Instead,
it has lodged discussion for many populations within broader
categories, most prominently ``mysticetes'' (14 populations) and
``odontocetes'' (37 populations), that in some cases correspond to
general taxonomic groups. Such grouping of stocks elides important
differences in abundance, demography, distribution, and other
population-specific factors, making it difficult to assume ``that the
effects of an activity on the different stock populations'' are
identical. That is particularly true where small, resident populations
are concerned, and differences in population abundance, habitat use,
and distribution relative to Navy activities can be profoundly
significant. Additionally, the commenter states that NMFS assumed that
all of the Navy's estimated impacts would not affect individuals or
populations through repeated activity--even though the takes
anticipated each year would affect the same populations and, indeed,
would admittedly involve extensive use of some of the same
biogeographic areas.
Response: NMFS provides information regarding broader groups in
order to avoid repeating information that is applicable across multiple
species or stocks, but analyses have been conducted and determinations
made specific to each stock. The method used to avoid repeating
information applicable to a number of species or stocks while also
presenting and integrating all information applicable to particular
species or stocks is described in the rule. Also, NMFS' analysis does
address the fact that some individuals may be repeatedly impacted and
how those impacts may or may not accrue to more serious effects. The
Analysis and Negligible Impacts Determination section has been expanded
and refined to better explain this.
Comment 80: NMFS' negligible impact analysis for Cuvier's beaked
whales is predicated on a single take estimate for the CA/OR/WA stock.
This is deeply problematic as the species is known to occur in small,
resident populations within the SOCAL Range Complex. These populations
are acutely vulnerable to Navy sonar. Cuvier's beaked whales have
repeatedly been associated with sonar-related pathology, are known to
react strongly to sonar at distances up to 100 kilometers, and are
universally regarded to be among the most sensitive of all marine
mammals to anthropogenic noise (Falcone et al., 2017). Some
populations, such as the one in San Nicholas Basin that coincides with
the Navy's much-used Southern California ASW Range (SOAR), are
repeatedly exposed to sonar, posing the same risk of population-wide
harm documented on a Navy range in the Bahamas (Falcone and Schorr,
2013). The broad take estimates presented in the Proposed Rule, and the
negligible impact analysis that they are meant to support, provide no
insight into the specific impacts proposed for these small populations.
Response: NMFS acknowledges the sensitivity of small resident
populations both in our analyses and in the identification of
mitigation measures, where appropriate. However, we are required to
make our negligible impact determination in the context of the MMPA-
designated stock, which, in the case of the CA/OR/WA stock of Cuvier's
beaked whale, spans the U.S. EEZ off the West Coast. As described in
our responses to previous comments, NMFS and the Navy have fully
accounted for the sensitivity of Cuvier's beaked whales in the
behavioral thresholds and the estimation of take. Further, contrary to
the assertions of the commenter, NMFS has absolutely considered the
potential impacts of repeated takes on individuals that show site
fidelity and that analysis can be found in the Analysis and Negligible
Impact Determination section, which has been refined and updated since
the proposed rule based on public input. Nonetheless, in 2018, an
estimate of overall abundance of Cuvier's beaked whales at the Navy's
instrumented range in San Nicolas Basin was obtained using new dive-
counting acoustic methods and an archive of passive acoustic M3R data
representing 35,416 hours of data (DiMarzio, 2018; Moretti, 2017). Over
the seven-year period from 2010-2017, there was no observed decrease
and perhaps a slight increase in annual Cuvier's beaked whale abundance
within San Nicolas Basin (DiMarzio, 2018). There does appear to be a
repeated dip in population numbers and associated echolocation clicks
during the fall centered around August and September (Moretti 2017,
DiMarzio 2018). A similar August and September dip was noted by
researchers using stand-alone off-range bottom passive acoustic devices
in Southern California ([Scaron]irovi[cacute] et al., 2016; Rice et
al., 2017). This dip in abundance may be tied to some as yet unknown
population dynamic or oceanographic and prey availability dynamics.
Comment 81: One commenter asserted that with respect to mortalities
and serious injuries, NMFS' application of potential biological removal
(PBR) is unclear and may not be consistent with its prior
interpretations. The agency recognizes that PBR is a factor in
determining whether the negligible impact threshold has been exceeded,
but argues that, since PBR and negligible impact are different
statutory standards, NMFS might find that an activity that kills marine
mammals beyond what PBR could support would not necessarily exceed the
negligible impact threshold. Regardless, however, of whether Congress
intended PBR as a formal constraint on NMFS' ability to issue
incidental take permits under section 101(a)(5), NMFS' own definition
of ``negligible impact'' prevents it from authorizing mortalities or
other takes that would threaten the sustainability of
[[Page 66912]]
marine mammal stocks. Mortalities and serious injuries exceeding
potential biological removal levels would do just that.
Additionally, in assessing the consequences of authorized mortality
below PBR, NMFS applies an ``insignificance'' standard, such that any
lethal take below 10 percent of residual PBR is presumed not to exceed
the negligible impact threshold. This approach seems inconsistent,
however, with the regulatory thresholds established for action under
the commercial fisheries provision of the Act, where bycatch of 1
percent of total PBR triggers mandatory take reduction procedures for
strategic marine mammal stocks. See 16 U.S.C. 1387(f)(1); 83 FR 5349,
5349 (Feb. 7, 2018). NMFS should clarify why it has chosen 10 percent
rather than, for example, 1 percent as its ``insignificance''
threshold, at least for endangered species and other populations
designated as strategic under the MMPA.
Response: NMFS disagrees that the consideration of PBR is unclear
and notes that the narrative describing the application of PBR has been
updated in this final rule to further explain how the agency considers
this metric in the context of the negligible impact determination under
section 101(a)(5)(A) (see the Serious Injury and Mortality sub-section
of the Analysis and Negligible Impact Determination section) and is not
repeated here. That discussion includes how PBR is calculated and
therefore how it is possible for anticipated M/SI to exceed PBR or
residual PBR and yet not adversely affect a particular species or stock
through effects on annual rates of recruitment and survival.
Regarding the insignificance threshold, as explained in the rule,
residual PBR is a metric that can be used to inform the assessment of
M/SI impacts, and the insignificance threshold is an analytical tool to
help prioritize analyst effort. But the insignificance threshold is not
applied as a strict presumption as described by the commenter. Although
it is true that as a general matter M/SI that is less than 10 percent
of residual PBR should have no effect on rates of recruitment or
survival, the agency will consider whether there are other factors that
should be considered, such as whether an UME is affecting the species
or stock.
The 10 percent insignificance threshold is an analytical tool that
indicates that the potential mortality or serious injury is an
insignificant incremental increase in anthropogenic mortality and
serious injury that alone (in the absence of any other take and any
other unusual circumstances) would clearly not affect rates of
recruitment or survival. As such, potential mortality and serious
injury at the insignificance-threshold level or below is evaluated in
light of other relevant factors (such as an ongoing UME) and then
considered in conjunction with any anticipated Level A or Level B
harassment take to determine if the total take would affect annual
rates of recruitment or survival. Ten percent was selected because it
corresponds to the insignificance threshold under the MMPA framework
for authorizing incidental take of marine mammals resulting from
commercial fisheries. There the insignificance threshold, which also is
10 percent of PBR, is ``the upper limit of annual incidental mortality
and serious injury of marine mammal stocks by commercial fisheries that
can be considered insignificant levels approaching a zero mortality and
serious injury rate'' (see 50 CFR 229.2). A threshold that represents
an insignificant level of mortality or serious injury approaching a
zero mortality and serious injury rate was thought to be an appropriate
level to indicate when, absent other factors, the agency can be
confident that expected mortality and serious injury will not affect
annual rates of recruitment and survival, without the need for
significant additional analysis.
Regarding the claim that NMFS' interpretation of PBR may be
inconsistent with prior interpretations, we disagree. Rather, NMFS'
interpretation of PBR has been utilized appropriately within the
context of the different MMPA programs and associated statutory
standards it has informed. The application of PBR under section
101(a)(5)(A) also has developed and been refined in response to
litigation and as the amount of and nature of M/SI requested pursuant
to this section has changed over time, thereby calling for the agency
to take a closer look at how M/SI relative to PBR relates to effects on
rates of recruitment and survival. Specifically, until recently, NMFS
had used PBR relatively few times to support determinations outside of
the context of MMPA commercial fisheries assessments and decisions.
Indeed, in Georgia Aquarium, Inc. v. Pritzker, 135 F. Supp.3d 1280
(N.D. Ga. 2015), in ruling on a lawsuit in which the plaintiffs sought
to use PBR as the reason they should be allowed to import animals from
the Sahklin-Amur stock of beluga whales for public display, the Court
summarized a ``handful'' of cases where NMFS had used PBR to support
certain agency findings. The Court agreed that the agency does not have
a ``practice and policy'' of applying PBR in all circumstances.
Importantly, the Court stated that ``NMFS has shown that where the
Agency has considered PBR outside of the U.S. commercial fisheries
context, it has treated PBR as only one `quantitative tool' and that it
is not used as the sole basis for its impact analyses,'' just as NMFS
has done here for its negligible impact analyses.
The examples considered by the Georgia Aquarium Court involved
scientific research permits or subsistence harvest decisions where
reference to PBR was one consideration among several. Thus, in one of
the examples referenced by the Court, PBR was included to evaluate
different alternatives in a 2007 EIS developed in support of future
grants and permits related to research on northern fur seals and
Steller sea lions (available at https://repository.library.noaa.gov/view/noaa/17331). Similarly, in the 2015 draft EIS on the Makah Tribe's
request to hunt gray whales, different levels of harvest were compared
against PBR along with other considerations in the various alternatives
(available at https://www.westcoast.fisheries.noaa.gov/publications/protected_species/marine_mammals/cetaceans/gray_whales/makah_deis_feb_2015.pdf). Consistent with what the Georgia Aquarium
Court found, in both of those documents PBR was one consideration in
developing alternatives for the agency's EIS and not determinative in
any decision-making process.
After 2013 in response to an incidental take authorization request
from NMFS' Southwest Fisheries Science Center that contained PBR
analysis and more particularly in response to a District Court's March
2015 ruling that NMFS' failure to consider PBR when evaluating lethal
take under section 101(a)(5)(A) violated the requirement to use the
best available science (see Conservation Council for Hawaii v. National
Marine Fisheries Service, 97 F. Supp.3d 1210 (D. Haw. 2015)), NMFS
began to systematically consider the role of PBR when evaluating the
effects of M/SI during section 101(a)(5)(A) rulemakings. Previously, in
1996 shortly after the PBR metric was first introduced, NMFS denied a
request from the U.S. Coast Guard for an incidental take authorization
for their vessel and aircraft operations, seemingly solely on the basis
of the potential for ship strike in relation to PBR. The decision did
not appear to consider other factors that might also have informed the
potential
[[Page 66913]]
for ship strike of a North Atlantic right whale in relation to the
negligible impact standard.
During the following years and until the Court's decision in
Conservation Council and the agency issuing the proposed incidental
take authorization for the Southwest Fisheries Science Center, NMFS
issued incidental take regulations without referencing PBR. Thereafter,
however, NMFS began considering and articulating the appropriate role
of PBR when processing incidental take requests for M/SI under section
101(a)(5)(A). Consistent with the interpretation of PBR across the rest
of the agency, NMFS' Permits and Conservation Division has been using
PBR as a tool to inform the negligible impact analysis under section
101(a)(5)(A), recognizing that it is not a dispositive threshold that
automatically determines whether a given amount of M/SI either does or
does not exceed a negligible impact on the affected species or stock.
Comment 82: A commenter commented that NMFS failed to adequately
assess the aggregate effects of all of the Navy's activities included
in the rule. The commenter alleges that NMFS' lack of analysis of these
aggregate impacts, which is essential to any negligible impact
determination, represents a glaring omission from the proposed rule.
While NMFS states that Level B behavioral harassment (aside from those
caused by masking effects) involves a stress response that may
contribute to an animal's allostatic load, it assumes without further
analysis that any such impacts would be insignificant.
Response: NMFS did analyze the potential for aggregate effects from
mortality, injury, masking, habitat effects, energetic costs, stress,
hearing loss, and behavioral harassment from the Navy's activities in
reaching the negligible impact determinations. Significant additional
discussion has been added to the Analysis and Negligible Impact
Determination section of the final rule to better explain the potential
for aggregate or cumulative effects on individuals as well as how these
effects on individuals relate to potential effects on annual rates of
recruitment and survival for each species or stock.
In addition, NMFS fully considers the potential for aggregate
effects from all Navy activities. We also consider UMEs and previous
environmental impacts, where appropriate, to inform the baseline levels
of both individual health and susceptibility to additional stressors,
as well as stock status. Further, the species and stock-specific
assessments in the Analysis and Negligible Impact Determination section
(which have been updated and expanded) pull together and address the
combined mortality, injury, behavioral harassment, and other effects of
the aggregate HSTT 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. We
refer the reader to the Analysis and Negligible Impact Determination
section for this analysis.
Widespread, extensive monitoring since 2006 on Navy ranges that
have been used for training and testing for decades has demonstrated no
evidence of population-level impacts. Based on the best available
research from NMFS and Navy-funded marine mammal studies, there is no
evidence that ``population-level harm'' to marine mammals, including
beaked whales, is occurring in the HSTT Study Area. The presence of
numerous small, resident populations of cetaceans, documented high
abundances, and populations trending to increase for many marine
mammals species in the area suggests there are not likely population-
level consequences resulting from decades of ongoing Navy training and
testing activities. Through the process described in the rule and the
LOAs, the Navy will work with NMFS to assure that the aggregate or
cumulative impacts remain at the negligible impact level.
Regarding the consideration of stress responses, NMFS does not
assume that the impacts are insignificant. There is currently neither
adequate data nor mechanism by which the impacts of stress from
acoustic exposure can be reliably and independently quantified.
However, stress effects that result from noise exposure likely often
occur concurrently with behavioral harassment and many are likely
captured and considered in the quantification of other takes by
harassment that occur when individuals come within a certain distance
of a sound source (behavioral harassment, PTS, and TTS).
Comment 83: Some Commenters asserted that in reaching our MMPA
negligible impact finding, NMFS did not adequately consider the
cumulative impacts of the Navy's activities when combined with the
effects of other non-Navy activities.
Response: Both the statute and the agency's implementing
regulations call for analysis of the effects of the applicant's
activities on the affected species and stocks, not analysis of other
unrelated activities and their impacts on the species and stocks. That
does not mean, however, that effects on the species and stocks caused
by other non-Navy activities are ignored. The preamble for NMFS'
implementing regulations under section 101(a)(5) (54 FR 40338;
September 29, 1989) explains in response to comments that the impacts
from other past and ongoing anthropogenic activities are to be
incorporated into the negligible impact analysis via their impacts on
the environmental baseline. Consistent with that direction, NMFS has
factored into its negligible impact analyses the impacts of other past
and ongoing anthropogenic activities via their impacts on the baseline
(e.g., as reflected in the density/distribution and status of the
species, population size and growth rate, and other relevant stressors
(such as incidental mortality in commercial fisheries or UMEs)). See
the Analysis and Negligible Impact Determination section of this rule.
Our 1989 final rule for the MMPA implementing regulations also
addressed public comments regarding cumulative effects from future,
unrelated activities. There we stated that such effects are not
considered in making findings under section 101(a)(5) concerning
negligible impact. We indicated that NMFS would consider cumulative
effects that are reasonably foreseeable when preparing a NEPA analysis
and also that reasonably foreseeable cumulative effects would be
considered under section 7 of the ESA for ESA-listed species.
Also, as described further in the Analysis and Negligible Impact
Determination section of the final rule, NMFS evaluated the impacts of
HSTT authorized mortality on the affected stocks in consideration of
other anticipated human-caused mortality, including the mortality
predicted in the SARs for other activities along with other NMFS-
permitted mortality (i.e., authorized as part of the Southwest
Fisheries Science Center rule), using multiple factors, including PBR.
As described in more detail in the Analysis and Negligible Impact
Determination section, PBR was designed to identify the maximum number
of animals that may be removed from a stock (not including natural
mortalities) while allowing that stock to reach or maintain its OSP and
is also helpful in informing whether mortality will adversely affect
annual rates of recruitment or survival in the context of a section
101(a)(5)(A).
NEPA
Comment 84: Commenters commented that NMFS cannot rely on
[[Page 66914]]
the Navy's HSTT FEIS/OEIS to fulfill its obligations under NEPA because
the purpose and need is too narrow and does not support NMFS' MMPA
action, and therefore the HSTT FEIS/OEIS does not explore a reasonable
range of alternatives.
Response: The proposed action at issue is the Navy's proposal to
conduct testing and training activities in the HSTT Study Area. NMFS is
a cooperating agency for that proposed action, as it has jurisdiction
by law and special expertise over marine resources impacted by the
proposed action, including marine mammals and federally-listed
threatened and endangered species. Consistent with the regulations
published by the Council on Environmental Quality (CEQ), it is common
and sound NEPA practice for NOAA to adopt a lead agency's NEPA analysis
when, after independent review, NOAA determines the document to be
sufficient in accordance with 40 CFR 1506.3. Specifically here, NOAA
must be satisfied that the Navy's EIS adequately addresses the impacts
of issuing the MMPA incidental take authorization and that NOAA's
comments and concerns have been adequately addressed. There is no
requirement in CEQ regulations that NMFS, as a cooperating agency,
issue a separate purpose and need statement in order to ensure adequacy
and sufficiency for adoption. Nevertheless, the Navy, in coordination
with NMFS, has clarified the statement of purpose and need in the HSTT
FEIS/OEIS to more explicitly acknowledge NMFS' action of issuing an
MMPA incidental take authorization. NMFS also clarified how its
regulatory role under the MMPA related to Navy's activities. NMFS'
early participation in the NEPA process and role in shaping and
informing analyses using its special expertise ensured that the
analysis in the HSTT FEIS/OEIS is sufficient for purposes of NMFS' own
NEPA obligations related to its issuance of incidental take
authorization under the MMPA.
Regarding the alternatives, NMFS' early involvement in development
of the HSTT EIS/OEIS and role in evaluating the effects of incidental
take under the MMPA ensured that the HSTT DEIS/OEIS would include
adequate analysis of a reasonable range of alternatives. The HSTT FEIS/
OEIS includes a No Action Alternative specifically to address what
could happen if NMFS did not issue an MMPA authorization. The other two
Alternatives address two action options that the Navy could potentially
pursue while also meeting their mandated Title 10 training and testing
responsibilities. More importantly, these alternatives fully analyze a
comprehensive variety of mitigation measures. This mitigation analysis
supported NMFS' evaluation of our options in potentially issuing an
MMPA authorization, which, if the authorization may be issued,
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. NOAA has independently reviewed and evaluated the EIS,
including the purpose and need statement and range of alternatives, and
determined that the HSTT FEIS/OEIS fully satisfies NMFS' NEPA
obligations related to its decision to issue the MMPA final rule and
associated LOAs, and we have adopted it.
Endangered Species Act
Comment 85: A commenter commented that under the ESA NMFS has the
discretion to impose terms, conditions, and mitigation on any
authorization. They believe the proposed action clearly affects listed
whales, sea turtles, and Hawaiian monk seals, triggering the duty to
consult. The commenter urged NMFS to fully comply with the ESA and
implement robust reasonable and prudent alternatives and conservation
measures to avoid harm to endangered species and their habitats.
Response: NMFS has fully complied with the ESA. The agency
consulted pursuant to section 7 of the ESA and NMFS' ESA Interagency
Cooperation Division provided a biological opinion concluded that NMFS'
action of issuing MMPA incidental take regulations for the Navy HSTT
activities would not jeopardize the continued existence of any
threatened or endangered species and nor would it adversely modify any
designated critical habitat. The biological opinion may be viewed at:
https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.
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 HSTT Study Area are presented in Table 13
along with an abundance estimate, an associated coefficient of
variation value, and best/minimum abundance estimates. The Navy
anticipates the take of 39 individual marine mammal species by Level A
and B harassment incidental to training and testing activities from the
use of sonar and other transducers, in-water detonations, air guns, and
impact pile driving/vibratory extraction activities. In addition, the
Navy requested authorization for ten serious injuries or mortalities
combined of two marine mammal stocks from explosives, and three takes
of large whales by serious injury or mortality from vessel strikes over
the five-year period. Two marine mammal species, the Hawaiian monk seal
and the Main Hawaiian Islands Insular false killer whale, have critical
habitat designated under the ESA in the HSTT Study Area (described
below).
The species considered but not carried forward for analysis are two
American Samoa stocks of spinner dolphins--(1) the Kure and Midway
stock and (2) the Pearl and Hermes stock. There is no potential for
overlap with any stressors from Navy activities and therefore there
would be no incidental takes, in which case, these stocks are not
considered further.
We presented a detailed discussion of marine mammals and their
occurrence in the planned action area, inclusive of ESA-designated
critical habitat, BIAs, National Marine Sanctuaries, and unusual
mortality events (UMEs) in our Federal Register notice of proposed
rulemaking (83 FR 29872; June 26, 2018); please see that notice of
proposed rulemaking or the Navy's application for more information.
There have been no changes or new information on BIAs and National
Marine Sanctuaries since publication of the proposed rule; therefore,
they are not discussed further. Additional information on certain ESA-
designated critical habitat and UMEs has become available and so both
of these topics are discussed following Table 13.
[[Page 66915]]
Table 13--Marine Mammal Occurrence Within the HSTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
Status Stock abundance
Common name Scientific name Stock ------------------------------------ Occurrence Seasonal (CV)/minimum
MMPA ESA absence population
--------------------------------------------------------------------------------------------------------------------------------------------------------
Blue whale................... Balaenoptera Eastern North Strategic, Endangered...... Southern ............... 1,647 (0.07)/
musculus. Pacific. Depleted. California. 1,551
Central North Strategic, Endangered...... Hawaii......... Summer......... 133 (1.09)/63
Pacific. Depleted.
Bryde's whale................ Balaenoptera Eastern Tropical ................ ................ Southern ............... unknown
brydei/edeni. Pacific. California.
Hawaii.......... ................ ................ Hawaii......... ............... 1,751 (0.29)/
1,378
Fin whale.................... Balaenoptera CA/OR/WA........ Strategic, Endangered...... Southern ............... 9,029 (0.12)/
physalus. Depleted. California. 8,127
Hawaii.......... Strategic, Endangered...... Hawaii......... Summer......... 154 (1.05)/75
Depleted.
Gray whale................... Eschrichtius Eastern North ................ ................ Southern ............... 26,960
robustus. Pacific. California. (0.05)/25,849
Western North Strategic, Endangered...... Southern ............... 175
Pacific. Depleted. California. (0.05)/167
Humpback whale............... Megaptera CA/OR/WA........ Strategic, Threatened/..... Southern ............... 2,900
novaeangliae. Depleted. Endangered \1\.. California. (0.03)/2,784
Central North Strategic....... ................ Hawaii......... Summer......... 10,103
Pacific. (0.30)/7,891
Minke whale.................. Balaenoptera CA/OR/WA........ ................ ................ Southern ............... 636
acutorostrata. California. (0.72)/369
Hawaii.......... ................ ................ Hawaii......... Summer......... unknown
Sei whale.................... Balaenoptera Eastern North Strategic, Endangered...... Southern ............... 519
borealis. Pacific. Depleted. California. (0.4)/374
Hawaii.......... Strategic, Endangered...... Hawaii......... Summer......... 391
Depleted. (0.90)/204
Sperm whale.................. Physeter CA/OR/WA........ Strategic, Endangered...... Southern ............... 1,997
macrocephalus. Depleted. California. (0.57)/1,270
Hawaii.......... Strategic, Endangered...... Hawaii......... ............... 4,559
Depleted. (0.33)/3,478
Pygmy sperm whale............ Kogia breviceps. CA/OR/WA........ ................ ................ Southern Winter and Fall 4,111
California. (1.12)/1,924
Hawaii.......... ................ ................ Hawaii......... ............... unknown
Dwarf sperm whale............ Kogia sima...... CA/OR/WA........ ................ ................ Southern ............... unknown
California.
Hawaii.......... ................ ................ Hawaii......... ............... unknown
Baird's beaked whale......... Berardius CA/OR/WA........ ................ ................ Southern ............... 2,697
bairdii. California. (0.6)/1,633
Blainville's beaked whale.... Mesoplodon Hawaii.......... ................ ................ Hawaii......... ............... 2,105
densirostris. (1.13)/980
Cuvier's beaked whale........ Ziphius CA/OR/WA........ ................ ................ Southern ............... 3,274
cavirostris. California. (0.67)/2,059
Hawaii.......... ................ ................ Hawaii......... ............... 723
0.69/428
Longman's beaked whale....... Indopacetus Hawaii.......... ................ ................ Hawaii......... ............... 7,619
pacificus. (0.66)/4,592
Mesoplodon beaked whales..... Mesoplodon spp.. CA/OR/WA........ ................ ................ Southern ............... 3,044
California. (0.54)/1,967
Common Bottlenose dolphin.... Tursiops California ................ ................ Southern ............... 453
truncatus. Coastal. California. (0.06)/346
CA/OR/WA ................ ................ Southern ............... 1,924
Offshore. California. (0.54)/1,255
Hawaii Pelagic.. ................ ................ Hawaii......... ............... 21,815
(0.57)/13.957
Kauai and Niihau ................ ................ Hawaii......... ............... NA
NA/97
Oahu............ ................ ................ Hawaii......... ............... NA
4-Islands....... ................ ................ Hawaii......... ............... NA
Hawaii Island... ................ ................ Hawaii......... ............... NA
NA/91
False killer whale........... Pseudorca Main Hawaiian Strategic, Endangered...... Hawaii......... ............... 167
crassidens. Islands Insular. Depleted. (0.14)/149
[[Page 66916]]
Hawaii Pelagic.. ................ ................ Hawaii......... ............... 1,540
(0.66)/928
Northwestern ................ ................ Hawaii......... ............... 617
Hawaiian (1.11)/290
Islands.
Fraser's dolphin............. Lagenodelphis Hawaii.......... ................ ................ Hawaii......... ............... 51,491
hosei. (0.66)/31,034
Killer whale................. Orcinus orca.... Eastern North ................ ................ Southern ............... 300
Pacific California. (0.1)/276
Offshore.
Eastern North ................ ................ Southern ............... 243
Pacific California. unknown/243
Transient/West
Coast Transient
\2\.
Hawaii.......... ................ ................ Hawaii......... ............... 146
(0.96)/74
Long-beaked common dolphin... Delphinus California...... ................ ................ Southern ............... 101,305
capensis. California. (0.49)/68,432
Melon-headed whale........... Peponocephala Hawaiian Islands ................ ................ Hawaii......... ............... 8,666
electra. (1.00)/4,299
Kohala Resident. ................ ................ Hawaii......... ............... 447
(0.12)/404
Northern right whale dolphin. Lissodelphis CA/OR/WA........ ................ ................ Southern ............... 26,556
borealis. California. (0.44)/18,608
Pacific white-sided dolphin.. Lagenorhynchus CA/OR/WA........ ................ ................ Southern ............... 26,814
obliquidens. California. (0.28)/21,195
Pantropical spotted dolphin.. Stenella Oahu............ ................ ................ Hawaii......... ............... unknown
attenuata.
4-Islands....... ................ ................ Hawaii......... ............... unknown
Hawaii Island... ................ ................ Hawaii......... ............... unknown
Hawaii Pelagic.. ................ ................ Hawaii......... ............... 55,795
(0.40)/40,338
Pygmy killer whale........... Feresa attenuata Tropical........ ................ ................ Southern Winter & Spring unknown
California.
Hawaii.......... ................ ................ Hawaii......... ............... 10,640
(0.53)/6,998
Risso's dolphins............. Grampus griseus. CA/OR/WA........ ................ ................ Southern ............... 6,336
California. (0.32)/4,817
Hawaii.......... ................ ................ Hawaii......... ............... 11,613
(0.43)/8,210
Rough-toothed dolphin........ Steno NSD \3\......... ................ ................ Southern ............... unknown
bredanensis. California.
Hawaii.......... ................ ................ Hawaii......... ............... 72,528
(0.39)/52,833
Short-beaked common dolphin.. Delphinus CA/OR/WA........ ................ ................ Southern ............... 969,861
delphis. California. (0.17)/839,325
Short-finned pilot whale..... Globicephala CA/OR/WA........ ................ ................ Southern ............... 836
macrorhynchus. California. (0.79)/466
Hawaii.......... ................ ................ Hawaii......... ............... 19,503
(0.49)/13,197
Spinner dolphin.............. Stenella Hawaii Pelagic.. ................ ................ Hawaii......... ............... unknown
longirostris.
Hawaii Island... ................ ................ Hawaii......... ............... 665
(0.09)/617
Oahu and 4- ................ ................ Hawaii......... ............... NA
Islands.
Kauai and Niihau ................ ................ Hawaii......... ............... NA
Kure and Midway. ................ ................ Hawaii......... ............... unknown
Pearl and Hermes ................ ................ Hawaii......... ............... unknown
Striped dolphin.............. Stenella CA/OR/WA........ ................ ................ Southern ............... 29,211
coeruleoalba. California. (0.20)/24,782
[[Page 66917]]
Hawaii.......... ................ ................ Hawaii......... ............... 61,021
(0.38)/44,922
Dall's porpoise.............. Phocoenoides CA/OR/WA........ ................ ................ Southern ............... 25,750
dalli. California. (0.45)/17,954
Harbor seal.................. Phoca vitulina.. California...... ................ ................ Southern ............... 30,968
California. NA/27,348
Hawaiian monk seal........... Neomonachus Hawaii.......... Strategic, Endangered...... Hawaii......... ............... 1,415
schauinslandi. Depleted. (0.03)/1,384
Northern elephant seal....... Mirounga California...... ................ ................ Southern ............... 179,000
angustirostris. California. NA/81,368
California sea lion.......... Zalophus U.S. Stock...... ................ ................ Southern ............... 257,606
californianus. California. NA/233,515
Guadalupe fur seal........... Arctocephalus Mexico to Strategic, Threatened...... Southern ............... 20,000
townsendi. California. Depleted. California. NA/15,830
Northern fur seal............ Callorhinus California...... ................ ................ Southern ............... 14,050
ursinus. California. NA/7,524
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The two humpback whale Distinct Population Segments making up the California, Oregon, and Washington stock present in Southern California are the
Mexico Distinct Population Segment, listed under the ESA as Threatened, and the Central America Distinct Population Segment, which is listed under the
ESA as Endangered.
\2\ This stock is mentioned briefly in the Pacific Stock Assessment Report (Carretta et al., 2017) and referred to as the ``Eastern North Pacific
Transient'' stock; however, the Alaska Stock Assessment Report contains assessments of all transient killer whale stocks in the Pacific and the Alaska
Stock Assessment Report refers to this same stock as the ``West Coast Transient'' stock (Muto et al., 2017).
\3\ NSD--No stock designation. Rough-toothed dolphin has a range known to include the waters off Southern California, but there is no recognized stock
or data available for the U.S. West Coast.
The proposed rule (83 FR 29909, June 26, 2018) includes a
description of ESA designated critical habitat, BIAs, National Marine
Sanctuaries, and unusual mortality events that are applicable in the
HSTT Study area and that material remains applicable and is not
repeated here. However, we do include information where anything has
changed. In this case, since the proposed rule was published, ESA
designated critical habitat for main Hawaiian Islands insular false
killer whales was finalized and new information regarding the
California sea lion UME became available.
Critical habitat for the ESA-listed Main Hawaiian Islands insular
false killer whale DPS was finalized in July 2018 (83 FR 35062; July
24, 2018) designating waters from the 45 m depth contour to the 3,200 m
depth contour around the main Hawaiian Islands from Niihau east to
Hawaii. This designation does not include most bays, harbors, or
coastal in-water structures. NMFS excluded 14 areas (one area, with two
sites, for the Bureau of Ocean Energy Management and 13 areas requested
by the Navy) from the critical habitat designation because it was
determined that the benefits of exclusion outweighed the benefits of
inclusion, and exclusion would not result in extinction of the species.
In addition, two areas, the Ewa Training Minefield and the Naval
Defensive Sea Area, were ineligible for designation because they are
managed under the Joint Base Pearl Harbor-Hickam Integrated Natural
Resources Management Plan that was found to benefit main Hawaiian
Islands insular false killer whales. The total area designated was
approximately 45,504 km\2\ (17,564 mi\2\) of marine habitat and the
designation stresses the importance of protecting: adequate space for
movement and use; prey species of sufficient quantity, quality, and
availability to support growth and reproduction; waters free of harmful
types and amounts of pollutants; and sound levels that would not
significantly impair false killer whale use or occupancy.
Regarding the California sea lion UME, although this UME has not
been closed, NMFS staff recently confirmed that the mortality of pups
and yearlings returned to normal in 2017 and 2018 and they plan to
present it to the Working Group to discuss closure by the end of 2018
(Deb Fauquier, pers. comm.). Please refer to the proposed rule (83 FR
29872; June 26, 2018) and NMFS' website at https://www.fisheries.noaa.gov/national/marine-life-distress/2013-2017-california-sea-lion-unusual-mortality-event-california for more
information on this UME.
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
We provided a summary and discussion of the potential effects of
the specified activity on marine mammals and their habitat in our
Federal Register notice of proposed rulemaking (83 FR 29872; June 26,
2018). 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 serious injury or mortality, physical trauma,
sensory impairment (permanent and temporary threshold shift and
acoustic masking), physiological responses (particular stress
responses), behavioral disturbance, or habitat effects. Therefore, we
do not reprint the information here but refer the reader to that
document. For additional summary and discussion of recent scientific
studies not included in the proposed rulemaking, we direct the reader
to the HSTT FEIS/OEIS (Chapter 3, Section 3.7 Marine Mammals, http://www.hstteis.com/), which NMFS participated in the development of via
our cooperating agency status and adopted to meet our NEPA
requirements. We highlight several studies below, but direct the reader
to the HSTT FEIS/OEIS for a full compilation. As noted above, NMFS has
reviewed and accepted the Navy's compilation and interpretation of the
best available science contained in the HSTT FEIS/OEIS. More
specifically, we have independently reviewed the more recent studies
that were not included in NMFS' proposed rule, have concluded that the
Navy's descriptions and interpretations of those studies in the
[[Page 66918]]
FEIS/OEIS are accurate, and have taken those studies into consideration
in our analyses that inform our negligible impact determinations.
Importantly, we note that none of the newer information highlighted
here or in the HSTT FEIS/OEIS affects our analysis in a manner that
changes our determinations under the MMPA from the proposed rule.
The Acoustic Technical Guidance (NMFS, 2018), which was used in the
assessment of effects for this action, compiled, interpreted, and
synthesized the best available scientific information for noise-induced
hearing effects for marine mammals to derive updated thresholds for
assessing the impacts of noise on marine mammal hearing. New data on
killer whale hearing (Branstetter et al., 2017), harbor porpoise
hearing (Kastelein et al., 2017a), harbor porpoise threshold shift (TS)
in response to airguns (Kastelein et al., 2017b) and mid-frequency
sonar (Kastelein et al., 2017c), and harbor seal TS in response to
pile-driving sounds (Kastelein et al., 2018) are consistent with data
included and thresholds presented in the Acoustic Technical Guidance.
Recent studies with captive odontocete species (bottlenose dolphin,
harbor porpoise, beluga, and false killer whale) have observed
increases in hearing threshold levels when individuals received a
warning sound prior to exposure to a relatively loud sound (Finneran,
2018; Nachtigall and Supin, 2013, 2015; Nachtigall et al., 2016a,b,c;
Nachtigall, et al., 2018). These studies suggest that captive animals
have a mechanism to reduce hearing sensitivity prior to impending loud
sounds. Hearing change was observed to be frequency dependent and
Finneran (2018) suggests hearing attenuation occurs within the cochlea
or auditory nerve. Based on these observations on captive odontocetes,
the authors suggest that wild animals may have a mechanism to self-
mitigate the impacts of noise exposure by dampening their hearing
during prolonged exposures of loud sound, or if conditioned to
anticipate intense sounds (Finneran, 2018, Nachtigall et al., 2018).
Recent reviews have synthesized data from experimental studies
examining marine mammal behavioral response to anthropogenic sound, and
have documented large variances in individual behavioral responses to
anthropogenic sound both within and among marine mammal species. These
reviews highlight the importance of the exposure context (e.g.,
behavioral state, presence of other animals and social relationships,
prey abundance, distance to source, presence of vessels, environmental
parameters, etc.) in determining or predicting a behavioral response.
As described in the proposed rule, in a review of experimental field
studies to measure behavioral responses of cetaceans to sonar, Southall
et al. (2016) observed that some individuals of different species
display clear yet varied responses (some of which have negative
implications), while others appear to tolerate high levels. Results
from the studies they investigated demonstrate that responses are
highly variable and may not be fully predictable with simple acoustic
exposure metrics (e.g., received sound level). Rather, differences
among species and individuals along with contextual aspects of exposure
(e.g., behavioral state) appear to affect response probability
(Southall et al., 2016). Dunlop et al. (2018) combined data from the
BRAHSS (Behavioural Response of Australian Humpback whales to Seismic
Surveys) studies designed to examine the behavioral responses of
migrating humpback whales to various seismic array sources to develop a
dose-response model. The model accounted for other variables such as
presence of the vessel, array towpath relative to the migration, and
social and environmental parameters. Authors observed that whales were
more likely to avoid the airgun or array (defined by increasing their
distance from the source) when they were exposed to sounds greater than
130 dB re 1 [mu]Pa\2\[middot]s and they were within 4 km of the source
(Dunlop et al., 2018). At sound exposure levels of 150-155 dB re 1
[mu]Pa\2\[middot]s and less than 2.5 km from the source the model
predicted a 50 percent probability of response (Dunlop et al., 2018).
However, it was not possible to estimate the maximum response threshold
as at the highest received levels of 160-170 dB re 1
[mu]Pa\2\[middot]s, a small number of whales moving rapidly and close
to the source did not exhibit an avoidance response as defined by the
study (Dunlop et al., 2018).
Estimated Take of Marine Mammals
This section indicates the number of takes that NMFS is
authorizing, which are based on the amount of take that NMFS
anticipates could occur or is 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 with one limited exception, agrees
that the methods the Navy put forth in their application 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. As noted elsewhere, additional
discussion and subsequent analysis led both NMFS and the Navy, in
coordination, to conclude that different take estimates for serious
injury or mortality from vessel strikes were appropriate, and where
those numbers differ from the Navy's application or our proposed rule,
NMFS has explicitly described our rationale and indicated what we
consider an appropriate number of takes.
Takes are predominantly in the form of harassment, but a small
number of serious injuries or mortalities are also authorized. For
military readiness activities, 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 would primarily be in the form of Level B
harassment, as use of the acoustic and explosive sources (i.e., sonar,
air guns, pile driving, explosives) is more likely to result in the
disruption of natural behavioral patterns to a point where they are
abandoned or significantly altered (as defined specifically in the
paragraph above, but referred to generally as behavioral disruption) or
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 and/or tissue damage (the latter from explosives only) to result
from exposure to the sound sources utilized in training and testing
activities. Lastly, a limited number of serious injuries or mortalities
could occur for California sea lion and short-beaked common dolphin (10
mortalities total between the two species over a five year period) from
explosives, and no more than three serious injuries or mortalities
total (over the five-year period) of large whales through vessel
collisions. Although we analyze the impacts of these potential serious
injuries or mortalities that are authorized, the required mitigation
and monitoring measures are expected to minimize the likelihood that
ship strike or these high level explosive exposures (and the associated
serious injury or mortality) actually occur.
[[Page 66919]]
Generally speaking, for acoustic impacts we estimate 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 Level B harassment (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 estimate.
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 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 new
Level B behavioral harassment thresholds have been refined here to
better consider the best available science (e.g., incorporating both
received level and distance), they also still, accordingly, 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
behavioral 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 Level
B behavioral harassment thresholds are the most appropriate method for
predicting Level B behavioral harassment given the best available
science and the associated uncertainty. Hearing Impairment (TTS/PTS and
Tissues Damage and Mortality)
Non-Impulsive and Impulsive
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, vibratory pile driving/
removal) and impulsive (explosives, airguns, impact pile driving)
sources.
These thresholds (Tables 14-15) 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 Acoustic Technical Guidance, which may be accessed at:
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.
Table 14--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 15
to predict the onset of TTS, PTS, tissue damage, and mortality for
explosives (impulsive) and other impulsive sound sources.
Table 15--Onset of TTS, PTS, Tissue Damage, and Mortality Thresholds for Marine Mammals for Explosives and Other Impulsive Sources
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mean onset slight Mean onset slight Mean onset
Functional hearing group Species Onset TTS 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.
[[Page 66920]]
Mid-frequency cetaceans.......... Most delphinids, 170 dB SEL 185 dB SEL 237 dB Peak SPL..
medium and large (weighted) or 224 (weighted) or 230
toothed whales. dB Peak SPL. dB Peak SPL.
High-frequency cetaceans......... Porpoises and Kogia 140 dB SEL 155 dB SEL 237 dB Peak SPL..
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 seal, (weighted) or 212 (weighted) or 218
Northern elephant dB Peak SPL. dB Peak SPL.
seal.
Otariidae........................ California sea lion, 188 dB SEL 203 dB SEL 237 dB Peak SPL..
Guadalupe fur seal, (weighted) or 226 (weighted) or 232
Northern fur seal. dB Peak SPL. dB Peak SPL.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
Equation 1: 47.5M1/3 (1+[DRm/10.1])1/6 Pa-sec.
Equation 2: 103M1/3 (1+[DRm/10.1])1/6 Pa-sec.
M = mass of the animals in kg.
DRm = depth of the receiver (animal) in meters.
SPL = sound pressure level.
Impulsive--Air Guns and Impact Pile Driving
Impact pile driving produces impulsive noise; therefore, the
criteria used to assess the onset of TTS and PTS are identical to those
used for air guns, as well as explosives (see Table 15 above) (see
Hearing Loss from Air Guns in Chapter 6 Section 6.4.3.1, Methods for
Analyzing Impacts from air guns in the Navy's rulemaking/LOA
application). 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.
Non-Impulsive--Sonar and Vibratory Pile Driving/Removal
Vibratory pile removal (that will be used during the ELCAS) creates
continuous non-impulsive noise at low source levels for a short
duration. Therefore, the criteria used to assess the onset of TTS and
PTS due to exposure to sonars (non-impulsive, see Table 14 above) are
also used to assess auditory impacts to marine mammals from vibratory
pile driving (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 in the Navy's rulemaking/LOA application). 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. Non-auditory injury (i.e., other than PTS) and mortality from
sonar and other transducers is so unlikely as to be discountable under
normal conditions for the reasons explained in the proposed rule under
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat section--Acoustically Mediated Bubble Growth and other
Pressure-related Injury and is therefore not considered further in this
analysis.
Behavioral Harassment
Though significantly driven by received level, the onset of Level B
harassment by behavioral disturbance from anthropogenic noise exposure
is 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 behavioral harassment.
Air Guns and Pile Driving
For air guns and pile driving, NMFS predicts that marine mammals
are likely to be taken by Level B behavioral harassment when exposed to
underwater anthropogenic noise above received levels of 120 dB re 1
[mu]Pa (rms) for continuous (e.g., vibratory pile-driving, drilling)
and above 160 dB re 1 [mu]Pa (rms) for non-explosive impulsive (e.g.,
seismic air guns) or intermittent (e.g., scientific sonar) sources. To
estimate Level B behavioral harassment from air guns, the existing NMFS
Level B harassment threshold of 160 dB re 1 [micro]Pa (rms) is used.
The rms calculation for air guns is based on the duration defined by 90
percent of the cumulative energy in the impulse.
The existing NMFS Level B harassment thresholds were also applied
to estimate Level B behavioral harassment from impact and vibratory
pile driving (Table 16).
Table 16--Pile Driving Level B Harassment Thresholds Used in This
Analysis To Predict Behavioral Responses From Marine Mammals
------------------------------------------------------------------------
Pile driving criteria (SPL, dB re 1 Level B harassment threshold
[mu]Pa) -----------------------------
-------------------------------------------
Underwater vibratory Underwater impact
------------------------------------------------------------------------
120 dB rms................................ 160 dB rms.
------------------------------------------------------------------------
Notes: Root mean square calculation for impact pile driving is based on
the duration defined by 90 percent of the cumulative energy in the
impulse. Root mean square for vibratory pile driving is calculated
based on a representative time series long enough to capture the
variation in levels, usually on the order of a few seconds. dB:
decibel; dB re 1 [micro]Pa: decibel referenced to 1 micropascal; rms:
root mean square.
Sonar
As noted above, the Navy coordinated with NMFS to propose Level B
behavioral harassment thresholds specific to their military readiness
[[Page 66921]]
activities utilizing active sonar. Behavioral response criteria are
used to estimate the number of animals that may exhibit a behavioral
response 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 the new Level B harassment
behavioral 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 Level B behavioral thresholds
and establishment of cutoff distances for the species, and agrees that
it is the best available science and is 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 the final rule.
As noted above, marine mammal responses to sound (some of which are
considered disturbances that rise to the level of 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; or
other prior experience of the individuals. This means that there is
support for considering alternative approaches for estimating Level B
behavioral harassment. Although the statutory definition of Level B
harassment for military readiness activities means that a natural
behavior 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 Level B behavioral
harassment threshold 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 ``significantly altering or abandoning 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 behavioral
harassment. We consider application of this Level B behavioral
harassment threshold, 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 being authorized.
In the Navy's acoustic impact analyses during Phase II, the
likelihood of Level B behavioral harassment in response to sonar and
other transducers was based on a probabilistic function (termed a
behavioral response 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. Of note, a separate step function at an SPL
of 120 dB re 1 [mu]Pa was used for harbor porpoises in the 2013-2018
rule, but there are no harbor porpoises in the HSTT Study Area (and
Dall's porpoises do not have the same behavioral sensitivities), so
harbor porpoises are not discussed further.
Developing the new Level B behavioral harassment criteria for Phase
III 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. 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 behavioral response
functions. Marine mammal species were placed into behavioral criteria
groups based on their known or suspected 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 Navy used cutoff distances beyond which the potential of
significant behavioral responses (and therefore Level B harassment) is
considered to be unlikely (see Table 17 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 behavioral response function based on a received SPL
as presented in Chapter 3, Section 3.1.0 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 @1 m, this cutoff
[[Page 66922]]
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 would rise to Level B harassment at farther
ranges as shown in Table 17, versus less intense events.
Table 17--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 [mu]Pa
@1 m
------------------------------------------------------------------------
Moderate SlL/
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
------------------------------------------------------------------------
Note: dB re 1 [mu]Pa @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 under each behavioral response function (or
step function in the case of the harbor porpoise) are shown in Table 18
through Table 22. 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 6.4.2.1.1 (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
behavioral response functions, thresholds, and the cutoff distances to
identify takes by Level B harassment, which were coordinated with NMFS.
Table 18 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 behavior patterns to a point where they are abandoned or
significantly altered) for LFAS. As noted previously, NMFS carefully
reviewed, and contributed to, the Navy's proposed level B behavioral
harassment thresholds and 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 66923]]
[GRAPHIC] [TIFF OMITTED] TR27DE18.020
Tables 19 through Table 21 identify the maximum likely percentage
of exposed individuals taken at the indicated received level and
associated range for MFAS.
[[Page 66924]]
[GRAPHIC] [TIFF OMITTED] TR27DE18.021
[[Page 66925]]
[GRAPHIC] [TIFF OMITTED] TR27DE18.022
[[Page 66926]]
[GRAPHIC] [TIFF OMITTED] TR27DE18.023
[[Page 66927]]
[GRAPHIC] [TIFF OMITTED] TR27DE18.024
Table 22 identifies the maximum likely percentage of exposed
individuals taken at the indicated received level and associated range
for HFAS.
Explosives
Phase III explosive criteria for Level B behavioral harassment
thresholds for marine mammals is the hearing groups' TTS threshold
minus 5 dB (see Table 23 below and Table 15 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.
[[Page 66928]]
Table 23--Phase III Level B Behavioral Harassment Thresholds for
Explosives for Marine Mammals
------------------------------------------------------------------------
Functional hearing SEL
Medium group (weighted)
------------------------------------------------------------------------
Underwater.......................... LF 163
Underwater.......................... MF 165
Underwater.......................... HF 135
Underwater.......................... PW 165
Underwater.......................... OW 183
------------------------------------------------------------------------
Note: Weighted SEL thresholds in dB re 1 [mu]Pa\2\s underwater. PW--
pinnipeds underwater, OW--otariids underwater.
Navy's Acoustic Effects Model
Sonar and Other Transducers and Explosives
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 HSTT 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 received
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. This 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 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 report (U.S. Department of
the Navy, 2018).
Air Guns and Pile Driving
The Navy's quantitative analysis estimates the sound and energy
received by marine mammals distributed in the area around planned Navy
activities involving air guns. See the technical report titled
Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: Methods
and Analytical Approach for Phase III Training and Testing report (U.S.
Department of the Navy, 2018) for additional details.
Underwater noise effects from pile driving and vibratory pile
extraction were modeled using actual measures of impact pile driving
and vibratory removal during construction of an ELCAS (Illingworth and
Rodkin, 2015, 2016). A conservative estimate of spreading loss of sound
in shallow coastal waters (i.e., transmission loss = 16.5*Log10
(radius)) was applied based on spreading loss observed in actual
measurements. Inputs used in the model are provided in Chapter 1,
Section 1.4.1.3 (Pile Driving) of the Navy's rulemaking/LOA
application, including source levels; the number of strikes required to
drive a pile and the duration of vibratory removal per pile; the number
of piles driven or removed per day; and the number of days of pile
driving and removal.
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 range 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 behavioral response function
(or step function in the case of the harbor porpoise) are shown in
Table 17 through Table 21 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 behavioral response functions,
thresholds, and the cutoff distances that are used to identify Level B
behavioral harassment.
The ranges to PTS for five representative sonar systems for an
exposure of 30 seconds is shown in Table 24 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.
[[Page 66929]]
Table 24--Range to Permanent Threshold Shift (Meters) for Five Representative Sonar Systems
----------------------------------------------------------------------------------------------------------------
Approximate range in meters for PTS from 30 seconds exposure
Functional hearing group -------------------------------------------------------------------------------
Sonar bin LF Sonar bin MF1 Sonar bin MF4 Sonar bin MF5 Sonar bin HF4
----------------------------------------------------------------------------------------------------------------
Low-frequency Cetacean.......... 0 (0-0) 65 (65-65) 14 (0-15) 0 (0-0) 0 (0-0)
Mid-frequency Cetacean.......... 0 (0-0) 16 (16-16) 3 (3-3) 0 (0-0) 1 (0-2)
High-frequency Cetacean......... 0 (0-0) 181 (180-190) 30 (30-30) 9 (8-10) 30 (8-80)
Otariidae....................... 0 (0-0) 6 (6-6) 0 (0-0) 0 (0-0) 0 (0-0)
Phocidae........................ 0 (0-0) 45 (45-45) 11 (11-11) 0 (0-0) 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 parenthesis.
The tables below illustrate the range to TTS for 1, 30, 60, and 120
seconds from five representative sonar systems (see Table 25 through
Table 29).
Table 25--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin LF5 Over a Representative Range of Environments Within the HSTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
Approximate TTS ranges (meters) \1\
-------------------------------------------------------------------------------------------
Hearing group Sonar bin LF5M (low frequency sources <180 dB source level)
-------------------------------------------------------------------------------------------
1 second 30 seconds 60 seconds 120 seconds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-frequency Cetacean...................................... 3 (0-4) 3 (0-4) 3 (0-4) 3 (0-4)
Mid-frequency Cetacean...................................... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
High-frequency Cetacean..................................... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
Otariidae................................................... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
Phocidae.................................................... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer
TTS extend 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 26--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin MF1 Over a Representative Range of Environments within the HSTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
Approximate TTS ranges (meters) \1\
-------------------------------------------------------------------------------------------
Hearing group Sonar bin MF1 (e.g., SQS-53 ASW hull-mounted sonar)
-------------------------------------------------------------------------------------------
1 second 30 seconds 60 seconds 120 seconds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-frequency Cetacean...................................... 903 (850-1,025) 903 (850-1,025) 1,264 (1,025-2,275) 1,839 (1,275-3,025)
Mid-frequency Cetacean...................................... 210 (210-210) 210 (210-210) 302 (300-310) 379 (370-390)
High-frequency Cetacean..................................... 3,043 (1,525-4,775) 3,043 (1,525-4,775) 4,739 (2,025-6,275) 5,614 (2,025-7,525)
Otariidae................................................... 65 (65-65) 65 (65-65) 106 (100-110) 137 (130-140)
Phocidae.................................................... 669 (650-725) 669 (650-725) 970 (900-1,025) 1,075 (1,025-1,525)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer
TTS extend 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 27--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin MF4 Over a Representative Range of Environments Within the HSTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
Approximate TTS ranges (meters) \1\
-------------------------------------------------------------------------------------------
Hearing group Sonar bin MF4 (e.g., AQS-22 ASW dipping sonar)
-------------------------------------------------------------------------------------------
1 second 30 seconds 60 seconds 120 seconds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-frequency Cetacean...................................... 77 (0-85) 162 (150-180) 235 (220-290) 370 (310-600)
Mid-frequency Cetacean...................................... 22 (22-22) 35 (35-35) 49 (45-50) 70 (70-70)
High-frequency Cetacean..................................... 240 (220-300) 492 (440-775) 668 (550-1,025) 983 (825-2,025)
Otariidae................................................... 8 (8-8) 15 (15-15) 19 (19-19) 25 (25-25)
[[Page 66930]]
Phocidae.................................................... 65 (65-65) 110 (110-110) 156 (150-170) 269 (240-460)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer
TTS extend 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 28--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin MF5 Over a Representative Range of Environments Within the HSTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
Approximate TTS ranges (meters) \1\
-------------------------------------------------------------------------------------------
Hearing group Sonar bin MF5 (e.g., SSQ-62 ASW Sonobuoy)
-------------------------------------------------------------------------------------------
1 second 30 seconds 60 seconds 120 seconds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-frequency Cetacean...................................... 10 (0-12) 10 (0-12) 14 (0-18) 21 (0-25)
Mid-frequency Cetacean...................................... 6 (0-9) 6 (0-9) 12 (0-13) 17 (0-21)
High-frequency Cetacean..................................... 118 (100-170) 118 (100-170) 179 (150-480) 273 (210-700)
Otariidae................................................... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
Phocidae.................................................... 9 (8-10) 9 (8-10) 14 (14-16) 21 (21-25)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer
TTS extend 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 29--Ranges to Temporary Threshold Shift (Meters) for Sonar Bin HF4 Over a Representative Range of Environments Within the HSTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
Approximate TTS ranges (meters) \1\
-------------------------------------------------------------------------------------------
Hearing group Sonar bin HF4 (e.g., SQS-20 mine hunting sonar)
-------------------------------------------------------------------------------------------
1 second 30 seconds >60 seconds 120 seconds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-frequency Cetacean...................................... 1 (0-3) 2 (0-5) 4 (0-7) 6 (0-11)
Mid-frequency Cetacean...................................... 10 (4-17) 17 (6-35) 24 (7-60) 34 (9-90)
High-frequency Cetacean..................................... 168 (25-550) 280 (55-775) 371 (80-1,275) 470 (100-1,525)
Otariidae................................................... 0 (0-0) 0 (0-0) 0 (0-0) 1 (0-1)
Phocidae.................................................... 2 (0-5) 5 (2-8) 8 (3-13) 11 (4-22)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Ranges to TTS represent the model predictions in different areas and seasons within the Study Area. The zone in which animals are expected to suffer
TTS extend 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 6.5.2.1.1 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 6.5.2.1.3, Navy Acoustic Effects Model 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 E12
(up to 1,000 lb net explosive weight) (Tables 30 through 34). Ranges
are determined by modeling the distance that noise from 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 behavioral 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 35 and 36,
respectively. Range to effects is important information in not only
predicting impacts from explosives, 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. For additional information on
how ranges to impacts from
[[Page 66931]]
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 30 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 30--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Behavioral Harassment for High-Frequency Cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: High frequency cetacean \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
Source Cluster
Bin depth (m) size PTS TTS Behavioral
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1.............................................. 0.1 1 353 (130-825) 1,234 (290-3,025) 2,141 (340-4,775)
25 1,188 (280-3,025) 3,752 (490-8,525) 5,196 (675-12,275)
E2.............................................. 0.1 1 425 (140-1,275) 1,456 (300-3,525) 2,563 (390-5,275)
10 988 (280-2,275) 3,335 (480-7,025) 4,693 (650-10,275)
E3.............................................. 0.1 1 654 (220-1,525) 2,294 (350-4,775) 3,483 (490-7,775)
12 1,581 (300-3,525) 4,573 (650-10,275) 6,188 (725-14,775)
18.25 1 747 (550-1,525) 3,103 (950-6,025) 5,641 (1,000-9,275)
12 1,809 (875-4,025) 7,807 (1,025-12,775) 10,798 (1,025-17,775)
E4.............................................. 3 2 2,020 (1,025-3,275) 3,075 (1,025-6,775) 3,339 (1,025-9,775)
15.25 2 970 (600-1,525) 4,457 (1,025-8,525) 6,087 (1,275-12,025)
19.8 2 1,023 (1,000-1,025) 4,649 (2,275-8,525) 6,546 (3,025-11,025)
198 2 959 (875-1,525) 4,386 (3,025-7,525) 5,522 (3,025-9,275)
E5.............................................. 0.1 25 2,892 (440-6,275) 6,633 (725-16,025) 8,925 (800-22,775)
15.25 25 4,448 (1,025-7,775) 10,504 (1,525-18,275) 13,605 (1,775-24,775)
E6.............................................. 0.1 1 1,017 (280-2,525) 3,550 (490-7,775) 4,908 (675-12,275)
3 1 2,275 (2,025-2,525) 6,025 (4,525-7,275) 7,838 (6,275-9,775)
15.25 1 1,238 (625-2,775) 5,613 (1,025-10,525) 7,954 (1,275-14,275)
E7.............................................. 3 1 3,150 (2,525-3,525) 7,171 (5,525-8,775) 8,734 (7,275-10,525)
18.25 1 2,082 (925-3,525) 6,170 (1,275-10,525) 8,464 (1,525-16,525)
E8.............................................. 0.1 1 1,646 (775-2,525) 4,322 (1,525-9,775) 5,710 (1,525-14,275)
45.75 1 1,908 (1,025-4,775) 5,564 (1,525-12,525) 7,197 (1,525-18,775)
E9.............................................. 0.1 1 2,105 (850-4,025) 4,901 (1,525-12,525) 6,700 (1,525-16,775)
E10............................................. 0.1 1 2,629 (875-5,275) 5,905 (1,525-13,775) 7,996 (1,525-20,025)
E11............................................. 18.5 1 3,034 (1,025-6,025) 7,636 (1,525-16,525) 9,772 (1,775-21,525)
45.75 1 2,925 (1,525-6,025) 7,152 (2,275-18,525) 9,011 (2,525-24,525)
E12............................................. 0.1 1 2,868 (975-5,525) 6,097 (2,275-14,775) 8,355 (4,275-21,275)
3 3,762 (1,525-8,275) 7,873 (3,775-20,525) 10,838 (4,275-26,525)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral thresholds are depicted above the minimum and maximum distances which are in parentheses. Values
depict the range produced by SEL hearing threshold criteria levels.
E13 not modeled due to surf zone use and lack of marine mammal receptors at site-specific location.
Table 31 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 31--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Behavioral Harassment for Mid-Frequency Cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: Mid-frequency cetacean \1\
---------------------------------------------------------------------------------------------------------------------------------------------------------
Source Cluster
Bin depth (m) size PTS TTS Behavioral
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1.............................................. 0.1 1 25 (25-25) 118 (80-210) 178 (100-320)
25 107 (75-170) 476 (150-1,275) 676 (240-1,525)
E2.............................................. 0.1 1 30 (30-35) 145 (95-240) 218 (110-400)
10 88 (65-130) 392 (140-825) 567 (190-1,275)
E3.............................................. 0.1 1 50 (45-65) 233 (110-430) 345 (130-600)
12 153 (90-250) 642 (220-1,525) 897 (270-2,025)
18.25 1 38 (35-40) 217 (190-900) 331 (290-850)
12 131 (120-250) 754 (550-1,525) 1,055 (600-2,525)
E4.............................................. 3 2 139 (110-160) 1,069 (525-1,525) 1,450 (875-1,775)
15.25 2 71 (70-75) 461 (400-725) 613 (470-750)
19.8 2 69 (65-70) 353 (350-360) 621 (600-650)
198 2 49 (0-55) 275 (270-280) 434 (430-440)
E5.............................................. 0.1 25 318 (130-625) 1,138 (280-3,025) 1,556 (310-3,775)
15.25 25 312 (290-725) 1,321 (675-2,525) 1,980 (850-4,275)
E6.............................................. 0.1 1 98 (70-170) 428 (150-800) 615 (210-1,525)
3 1 159 (150-160) 754 (650-850) 1,025 (1,025-1,025)
15.25 1 88 (75-180) 526 (450-875) 719 (500-1,025)
[[Page 66932]]
E7.............................................. 3 1 240 (230-260) 1,025 (1,025-1,025) 1,900 (1,775-2,275)
18.25 1 166 (120-310) 853 (500-1,525) 1,154 (550-1,775)
E8.............................................. 0.1 1 160 (150-170) 676 (500-725) 942 (600-1,025)
45.75 1 128 (120-170) 704 (575-2,025) 1,040 (750-2,525)
E9.............................................. 0.1 1 215 (200-220) 861 (575-950) 1,147 (650-1,525)
E10............................................. 0.1 1 275 (250-480) 1,015 (525-2,275) 1,424 (675-3,275)
E11............................................. 18.5 1 335 (260-500) 1,153 (650-1,775) 1,692 (775-3,275)
45.75 1 272 (230-825) 1,179 (825-3,025) 1,784 (1,000-4,275)
E12............................................. 0.1 1 334 (310-350) 1,151 (700-1,275) 1,541 (800-3,525)
0.1 3 520 (450-550) 1,664 (800-3,525) 2,195 (925-4,775)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral thresholds are depicted above the minimum and maximum distances which are in parentheses. Values
depict the range produced by SEL hearing threshold criteria levels.
E13 not modeled due to surf zone use and lack of marine mammal receptors at site-specific location.
Table 32 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 32--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Behavioral Harassment for Low-Frequency Cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: Low frequency cetacean 1
---------------------------------------------------------------------------------------------------------------------------------------------------------
Source Cluster
Bin depth (m) size PTS TTS Behavioral
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1.............................................. 0.1 1 51 (40-70) 227 (100-320) 124 (70-160)
25 205 (95-270) 772 (270-1,275) 476 (190-725)
E2.............................................. 0.1 1 65 (45-95) 287 (120-400) 159 (80-210)
10 176 (85-240) 696 (240-1,275) 419 (160-625)
E3.............................................. 0.1 1 109 (65-150) 503 (190-1,000) 284 (120-430)
12 338 (130-525) 1,122 (320-7,775) 761 (240-6,025)
18.25 1 205 (170-340) 996 (410-2,275) 539 (330-1,275)
12 651 (340-1,275) 3,503 (600-8,275) 1,529 (470-3,275)
E4.............................................. 3 2 493 (440-1,000) 2,611 (1,025-4,025) 1,865 (950-2,775)
15.25 2 583 (350-850) 3,115 (1,275-5,775) 1,554 (1,000-2,775)
19.8 2 378 (370-380) 1,568 (1,275-1,775) 926 (825-950)
198 2 299 (290-300) 2,661 (1,275-3,775) 934 (900-950)
E5.............................................. 0.1 25 740 (220-6,025) 2,731 (460-22,275) 1,414 (350-14,275)
15.25 25 1,978 (1,025-5,275) 8,188 (3,025-19,775) 4,727 (1,775-11,525)
E6.............................................. 0.1 1 250 (100-420) 963 (260-7,275) 617 (200-1,275)
3 1 711 (525-825) 3,698 (1,525-4,275) 2,049 (1,025-2,525)
15.25 1 718 (390-2,025) 3,248 (1,275-8,525) 1,806 (950-4,525)
E7.............................................. 3 1 1,121 (850-1,275) 5,293 (2,025-6,025) 3,305 (1,275-4,025)
18.25 1 1,889 (1,025-2,775) 6,157 (2,775-11,275) 4,103 (2,275-7,275)
E8.............................................. 0.1 1 460 (170-950) 1,146 (380-7,025) 873 (280-3,025)
45.75 1 1,049 (550-2,775) 4,100 (1,025-14,275) 2,333 (800-7,025)
E9.............................................. 0.1 1 616 (200-1,275) 1,560 (450-12,025) 1,014 (330-5,025)
E10............................................. 0.1 1 787 (210-2,525) 2,608 (440-18,275) 1,330 (330-9,025)
E11............................................. 18.5 1 4,315 (2,025-8,025) 10,667 (4,775-26,775) 7,926 (3,275-21,025)
45.75 1 1,969 (775-5,025) 9,221 (2,525-29,025) 4,594 (1,275-16,025)
E12............................................. 0.1 1 815 (250-3,025) 2,676 (775-18,025) 1,383 (410-8,525)
0.1 3 1,040 (330-6,025) 4,657 (1,275-31,275) 2,377 (700-16,275)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral thresholds are depicted above the minimum and maximum distances, which are in parentheses. Values
depict the range produced by SEL hearing threshold criteria levels.
E13 not modeled due to surf zone use and lack of marine mammal receptors at site-specific location.
Table 33 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 phocids based on the developed thresholds.
[[Page 66933]]
Table 33--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Behavioral Harassment for Phocids
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: Phocids 1
---------------------------------------------------------------------------------------------------------------------------------------------------------
Source Cluster
Bin depth (m) size PTS TTS Behavioral
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1.............................................. 0.1 1 45 (40-65) 210 (100-290) 312 (130-430)
25 190 (95-260) 798 (280-1,275) 1,050 (360-2,275)
E2.............................................. 0.1 1 58 (45-75) 258 (110-360) 383 (150-550)
10 157 (85-240) 672 (240-1,275) 934 (310-1,525)
E3.............................................. 0.1 1 96 (60-120) 419 (160-625) 607 (220-900)
12 277 (120-390) 1,040 (370-2,025) 1,509 (525-6,275)
18.25 1 118 (110-130) 621 (500-1,275) 948 (700-2,025)
12 406 (330-875) 1,756 (1,025-4,775) 3,302 (1,025-6,275)
E4.............................................. 3 2 405 (300-430) 1,761 (1,025-2,775) 2,179 (1,025-3,275)
15.25 2 265 (220-430) 1,225 (975-1,775) 1,870 (1,025-3,275)
19.8 2 220 (220-220) 991 (950-1,025) 1,417 (1,275-1,525)
198 2 150 (150-150) 973 (925-1,025) 2,636 (2,025-3,525)
E5.............................................. 0.1 25 569 (200-850) 2,104 (725-9,275) 2,895 (825-11,025)
15.25 25 920 (825-1,525) 5,250 (2,025-10,275) 7,336 (2,275-16,025)
E6.............................................. 0.1 1 182 (90-250) 767 (270-1,275) 1,011 (370-1,775)
3 1 392 (340-440) 1,567 (1,275-1,775) 2,192 (2,025-2,275)
15.25 1 288 (250-600) 1,302 (1,025-3,275) 2,169 (1,275-5,775)
E7.............................................. 3 1 538 (450-625) 2,109 (1,775-2,275) 2,859 (2,775-3,275)
18.25 1 530 (460-750) 2,617 (1,025-4,525) 3,692 (1,525-5,275)
E8.............................................. 0.1 1 311 (290-330) 1,154 (625-1,275) 1,548 (725-2,275)
45.75 1 488 (380-975) 2,273 (1,275-5,275) 3,181 (1,525-8,025)
E9.............................................. 0.1 1 416 (350-470) 1,443 (675-2,025) 1,911 (800-3,525)
E10............................................. 0.1 1 507 (340-675) 1,734 (725-3,525) 2,412 (800-5,025)
E11............................................. 18.5 1 1,029 (775-1,275) 5,044 (2,025-8,775) 6,603 (2,525-14,525)
45.75 1 881 (700-2,275) 3,726 (2,025-8,775) 5,082 (2,025-13,775)
E12............................................. 0.1 1 631 (450-750) 1,927 (800-4,025) 2,514 (925-5,525)
0.1 3 971 (550-1,025) 2,668 (1,025-6,275) 3,541 (1,775-9,775)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral thresholds are depicted above the minimum and maximum distances which are in parentheses. Values
depict the range produced by SEL hearing threshold criteria levels.
E13 not modeled due to surf zone use and lack of marine mammal receptors at site-specific location.
Table 34 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 ottariids based on the developed thresholds.
Table 34--SEL-Based Ranges (Meters) to Onset PTS, Onset TTS, and Level B Behavioral Harassment for Otariids
--------------------------------------------------------------------------------------------------------------------------------------------------------
Range to effects for explosives: Otariids 1
---------------------------------------------------------------------------------------------------------------------------------------------------------
Source Cluster
Bin depth (m) size PTS TTS Behavioral
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1.............................................. 0.1 1 7 (7-7) 34 (30-40) 56 (45-70)
25 30 (25-35) 136 (80-180) 225 (100-320)
E2.............................................. 0.1 1 9 (9-9) 41 (35-55) 70 (50-95)
10 25 (25-30) 115 (70-150) 189 (95-250)
E3.............................................. 0.1 1 16 (15-19) 70 (50-95) 115 (70-150)
12 45 (35-65) 206 (100-290) 333 (130-450)
18.25 1 15 (15-15) 95 (90-100) 168 (150-310)
12 55 (50-60) 333 (280-750) 544 (440-1,025)
E4.............................................. 3 2 64 (40-85) 325 (240-340) 466 (370-490)
15.25 2 30 (30-35) 205 (170-300) 376 (310-575)
19.8 2 25 (25-25) 170 (170-170) 290 (290-290)
198 2 17 (0-25) 117 (110-120) 210 (210-210)
E5.............................................. 0.1 25 98 (60-120) 418 (160-575) 626 (240-1,000)
15.25 25 151 (140-260) 750 (650-1,025) 1,156 (975-2,025)
E6.............................................. 0.1 1 30 (25-35) 134 (75-180) 220 (100-320)
3 1 53 (50-55) 314 (280-390) 459 (420-525)
15.25 1 36 (35-40) 219 (200-380) 387 (340-625)
E7.............................................. 3 1 93 (90-100) 433 (380-500) 642 (550-800)
18.25 1 73 (70-75) 437 (360-525) 697 (600-850)
E8.............................................. 0.1 1 50 (50-50) 235 (220-250) 385 (330-450)
45.75 1 55 (55-60) 412 (310-775) 701 (500-1,525)
E9.............................................. 0.1 1 68 (65-70) 316 (280-360) 494 (390-625)
[[Page 66934]]
E10............................................. 0.1 1 86 (80-95) 385 (240-460) 582 (390-800)
E11............................................. 18.5 1 158 (150-200) 862 (750-975) 1,431 (1,025-2,025)
45.75 1 117 (110-130) 756 (575-1,525) 1,287 (950-2,775)
E12............................................. 0.1 1 104 (100-110) 473 (370-575) 709 (480-1,025)
0.1 3 172 (170-180) 694 (480-1,025) 924 (575-1,275)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral thresholds are depicted above the minimum and maximum distances which are in parentheses. Values
depict the range produced by SEL hearing threshold criteria levels.
E13 not modeled due to surf zone use and lack of marine mammal receptors at site-specific location.
Table 35 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 35--Ranges \1\ to 50 Percent Non-Auditory Injury Risk for All
Marine Mammal Hearing Groups
------------------------------------------------------------------------
Bin Range (m) (min-max)
------------------------------------------------------------------------
E1............................................ 12 (11-13)
E2............................................ 15 (15-20)
E3............................................ 25 (25-30)
E4............................................ 32 (0-75)
E5............................................ 40 (35-140)
E6............................................ 52 (40-120)
E7............................................ 145 (100-500)
E8............................................ 117 (75-400)
E9............................................ 120 (90-290)
E10........................................... 174 (100-480)
E11........................................... 443 (350-1,775)
E12........................................... 232 (110-775)
------------------------------------------------------------------------
Note: \1\ Average distance (m) to mortality is depicted above the
minimum and maximum distances which are in parentheses.
E13 not modeled due to surf zone use and lack of marine mammal receptors
at site-specific location. Differences between bins E11 and E12 due to
different ordnance types and differences in model parameters.
Ranges to mortality, based on animal mass, are show in Table 36
below.
Table 36--Ranges \1\ to 50 Percent Mortality Risk for All Marine Mammal Hearing Groups as a Function of Animal Mass
--------------------------------------------------------------------------------------------------------------------------------------------------------
Animal mass intervals (kg) \1\
Bin -----------------------------------------------------------------------------------------------------
10 250 1,000 5,000 25,000 >72,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1................................................ 3 (2-3) 0 (0-3) 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
E2................................................ 4 (3-5) 1 (0-4) 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0)
E3................................................ 8 (6-10) 4 (2-8) 1 (0-2) 0 (0-0) 0 (0-0) 0 (0-0)
E4................................................ 15 (0-35) 9 (0-30) 4 (0-8) 2 (0-6) 0 (0-3) 0 (0-2)
E5................................................ 13 (11-45) 7 (4-35) 3 (3-12) 2 (0-8) 0 (0-2) 0 (0-2)
E6................................................ 18 (14-55) 10 (5-45) 5 (3-15) 3 (2-10) 0 (0-3) 0 (0-2)
E7................................................ 67 (55-180) 35 (18-140) 16 (12-30) 10 (8-20) 5 (4-9) 4 (3-7)
E8................................................ 50 (24-110) 27 (9-55) 13 (0-20) 9 (4-13) 4 (0-6) 3 (0-5)
E9................................................ 32 (30-35) 20 (13-30) 10 (8-12) 7 (6-9) 4 (3-4) 3 (2-3)
E10............................................... 56 (40-190) 25 (16-130) 13 (11-16) 9 (7-11) 5 (4-5) 4 (3-4)
E11............................................... 211 (180-500) 109 (60-330) 47 (40-100) 30 (25-65) 15 (0-25) 13 (11-22)
E12............................................... 94 (50-300) 35 (20-230) 16 (13-19) 11 (9-13) 6 (5-8) 5 (4-8)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: \1\ Average distance (m) to mortality is depicted above the minimum and maximum distances which are in parentheses.
E13 not modeled due to surf zone use and lack of marine mammal receptors at site-specific location.
Differences between bins E11 and E12 due to different ordnance types and differences in model parameters (see Table 6-42 for details).
[[Page 66935]]
Air Guns
Table 37 and Table 38 present the approximate ranges in meters to
PTS, TTS, and likely behavioral responses that rise to the level of a
take for air guns for 1 and 10 pulses, respectively. Ranges are
specific to the HSTT Study Area and also to each marine mammal hearing
group, dependent upon their criteria and the specific locations where
animals from the hearing groups and the air gun activities could
overlap. Small air guns (12-60 in\3\) would be used during testing
activities in the offshore areas of the Southern California Range
Complex and in the Hawaii Range Complex. Generated impulses would have
short durations, typically a few hundred milliseconds, with dominant
frequencies below 1 kHz. The SPL and SPL peak (at a distance 1 m from
the air gun) would be approximately 215 dB re 1 [micro]Pa and 227 dB re
1 [micro]Pa, respectively, if operated at the full capacity of 60
in\3\. The size of the air gun chamber can be adjusted, which would
result in lower SPLs and SEL per shot. Single, small air guns lack the
peak pressures that could cause non-auditory injury (see Finneran et
al., 2015); therefore, potential impacts could include PTS, TTS, and/or
Level B behavioral harassment.
Table 37--Range to Effects (Meters) From Air Guns for 1 Pulse
----------------------------------------------------------------------------------------------------------------
Range to effects for air guns \1\ for 1 pulse (m)
-----------------------------------------------------------------------------------------------------------------
Hearing group PTS (SEL) PTS (Peak SPL) TTS (SEL) TTS (Peak SPL) Behavioral \2\
----------------------------------------------------------------------------------------------------------------
High-Frequency Cetacean...... 0 (0-0) 18 (15-25) 1 (0-2) 33 (25-80) 702 (290-1,525)
Low-Frequency Cetacean....... 3 (3-4) 2 (2-3) 27 (23-35) 5 (4-7) 651 (200-1,525)
Mid-Frequency Cetacean....... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0) 689 (290-1,525)
Otariidae.................... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0) 590 (290-1,525)
Phocidae..................... 0 (0-0) 2 (2-3) 0 (0-0) 5 (4-8) 668 (290-1,525)
----------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral thresholds are depicted above the minimum and maximum
distances which are in parentheses. PTS and TTS values depict the range produced by SEL and Peak SPL (as
noted) hearing threshold criteria levels.
\2\ Behavioral values depict the ranges produced by RMS hearing threshold criteria levels.
Table 38--Range to Effects (Meters) From Air Guns for 10 Pulses
----------------------------------------------------------------------------------------------------------------
Range to Effects for Air Guns \1\ for 10 pulses (m)
-----------------------------------------------------------------------------------------------------------------
Hearing group PTS (SEL) PTS (Peak SPL) TTS (SEL) TTS (Peak SPL) Behavioral \2\
----------------------------------------------------------------------------------------------------------------
High-Frequency Cetacean...... 0 (0-0) 18 (15-25) 3 (0-9) 33 (25-80) 702 (290-1,525)
Low-Frequency Cetacean....... 15 (12-20) 2 (2-3) 86 (70-140) 5 (4-7) 651 (200-1,525)
Mid-Frequency Cetacean....... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0) 689 (290-1,525)
Otariidae.................... 0 (0-0) 0 (0-0) 0 (0-0) 0 (0-0) 590 (290-1,525)
Phocidae..................... 0 (0-0) 2 (2-3) 4 (3-5) 5 (4-8) 668 (290-1,525)
----------------------------------------------------------------------------------------------------------------
\1\ Average distance (m) to PTS, TTS, and behavioral thresholds are depicted above the minimum and maximum
distances which are in parentheses. PTS and TTS values depict the range produced by SEL and Peak SPL (as
noted) hearing threshold criteria levels.
\2\ Behavioral values depict the ranges produced by RMS hearing threshold criteria levels.
Pile Driving
Table 39 and Table 40 present the approximate ranges in meters to
PTS, TTS, and/or Level B behavioral harassment that rise to the level
of a take for impact pile driving and vibratory pile removal,
respectively. Non-auditory injury is not predicted for pile driving
activities.
Table 39--Average Ranges to Effects (Meters) From Impact Pile Driving
----------------------------------------------------------------------------------------------------------------
Hearing group PTS (m) TTS (m) Behavioral (m)
----------------------------------------------------------------------------------------------------------------
Low-Frequency Cetaceans......................................... 65 529 870
Mid-Frequency Cetaceans......................................... 2 16 870
High-Frequency Cetaceans........................................ 65 529 870
Phocidae........................................................ 19 151 870
Otariidae....................................................... 2 12 870
----------------------------------------------------------------------------------------------------------------
Note: PTS: permanent threshold shift; TTS: temporary threshold shift.
Table 40--Average Ranges to Effect (Meters) From Vibratory Pile Extraction
----------------------------------------------------------------------------------------------------------------
Hearing group PTS (m) TTS (m) Behavioral (m)
----------------------------------------------------------------------------------------------------------------
Low-Frequency Cetaceans......................................... 0 3 376
Mid-Frequency Cetaceans......................................... 0 4 376
High-Frequency Cetaceans........................................ 7 116 376
Phocidae........................................................ 0 2 376
Otariidae....................................................... 0 0 376
----------------------------------------------------------------------------------------------------------------
Note: PTS: permanent threshold shift; TTS: temporary threshold shift.
[[Page 66936]]
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 the 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; 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.
To characterize the marine species density for large areas such as
the HSTT Study Area, the Navy compiled data from several sources. The
Navy developed a protocol to select the best available data sources
based on species, area, and time (season). The resulting Geographic
Information System database, called the Navy Marine Species Density
Database includes seasonal density values for every marine mammal
species present within the HSTT Study Area. This database is described
in the technical report titled U.S. Navy Marine Species Density
Database Phase III for the Hawaii-Southern California Training and
Testing Study Area (U.S. Department of the Navy, 2017e), hereafter
referred to as the Density Technical Report.
A variety of density data and density models are needed in order to
develop a density database that encompasses the entirety of the HSTT
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
Density Technical Report describes these models in detail and provides
detailed explanations of the models applied to each species density
estimate. The below list 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. In the HSTT analysis, due to the
availability of other density methods along the hierarchy the use of
RES model was not necessary.
When interpreting the results of the quantitative analysis, as
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 the density estimates
used) in the HSTT Study Area may differ from population abundances
estimated in the NMFS' SARS in some cases for a variety of reasons.
Models may predict different population abundances for many reasons,
including being based on different data sets, different areas, or
different time periods. The SARs are often based on single years of
NMFS surveys, whereas the models used by the Navy generally include
multiple years of survey data from NMFS, the Navy, and other sources.
To present a single, best estimate, the SARs often use a single season
survey where they have the best spatial coverage (generally Summer).
Navy models often use predictions for multiple seasons, where
appropriate for the species, even when survey coverage in non-Summer
seasons is limited, to characterize impacts over multiple seasons as
Navy activities may occur in any season. Predictions may be made for
different spatial extents. For
[[Page 66937]]
example, the SAR encompasses the U.S. EEZ, while the HSTT Study area
overlaps only part of the U.S. EEZ (specifically, the Pacific SAR
overlaps only 35 percent of the Hawaii part of the HSTT Study Area and
only about 14 percent of SOCAL), but alternately extends out
significantly beyond it to the West. Many different, but equally valid,
habitat and density modeling techniques exist and these can also be the
cause of differences in population predictions. Differences in
population estimates may be caused by a combination of these factors.
Even similar estimates should be interpreted with caution and
differences in models fully understood before drawing conclusions.
The global population structure of humpbacks, with 14 DPSs all
associated with multiple feeding areas at which individuals from
multiple DPSs convene, is another reason that SAR abundance estimates
can differ from other estimates and be somewhat confusing--the same
individuals are addressed in multiple SARs. 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 because the
HSTT Study Area extends well 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.
These factors and others described in the Density Technical Report
should be considered when examining the estimated impact numbers in
comparison to current population abundance information for any given
species or stock. For a detailed description of the density and
assumptions made for each species, see the Density Technical Report.
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, and the
rationale for which abundance estimate is used is included there.
Take Requests
The HSTT FEIS/OEIS considered all training and testing activities
proposed to occur in the HSTT 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 of marine
mammals from the Navy's planned activities.
Acoustics (sonar and other transducers; air guns; pile
driving/extraction).
Explosives (explosive shock wave and sound (assumed to
encompass the risk due to fragmentation)).
Physical Disturbance and Strike (vessel strike).
NMFS reviewed, and agrees with, the Navy's conclusion that acoustic
and explosive sources have the potential to result in incidental takes
of marine mammals by harassment, serious injury, or mortality. NMFS
carefully reviewed the Navy's analysis and conducted its own analysis
of vessel strikes, determining that the likelihood of any particular
species of large whale being struck is quite low. Nonetheless, NMFS
agrees that vessel strikes have the potential to result in incidental
take from serious injury or mortality for certain species of large
whales and the Navy has specifically requested coverage for these
species. Therefore, the likelihood of vessel strikes, and later the
effects of the incidental take that is being authorized, has been fully
analyzed and is described below.
The quantitative analysis process used for the HSTT FEIS/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 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 report (U.S.
Department of the Navy, 2018). The Navy Acoustic Effects Model
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 mitigation is expected to reduce model-estimated PTS to TTS
for exposures to sonar and other transducers, and reduce model-
estimated mortality to injury for exposures to explosives. The extent
to which the mitigation areas reduce impacts on the affected species
and stocks is addressed separately in the Analysis and Negligible
Impact Determination section.
The Navy assessed the effectiveness of its procedural 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).
During 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 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 only account 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.
The Navy used the equations in the below sections to calculate the
reduction in model-estimated mortality impacts due to implementing
procedural mitigation.
Equation 1:
Mitigation Effectiveness = Species Sightability x Visibility x
Observation Area x Positive Control
Species Sightability is the ability to detect marine mammals and is
dependent on the animal's presence at the surface and the
characteristics of the animal that influence its sightability. The Navy
considered applicable data from the best available science to
numerically approximate the sightability of marine mammals and
[[Page 66938]]
determined the standard ``detection probability'' referred to as g(0)
is most appropriate. Also, Visibility = 1 - sum of individual
visibility reduction factors; Observation Area = portion of impact
range that can be continuously observed during an event; and Positive
Control = positive control factor of all sound sources involving
mitigation. For further details on these mitigation effectiveness
factors please refer to the technical report titled Quantifying
Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and
Analytical Approach for Phase III Training and Testing report (U.S.
Department of the Navy, 2018).
To quantify the number of marine mammals predicted to be sighted by
Lookouts during implementation of procedural mitigation in the range to
injury (PTS) for sonar and other transducers, the species sightability
is multiplied by the mitigation effectiveness scores and number of
model-estimated PTS impacts, as shown in the equation below:
Equation 2:
Number of Animals Sighted by Lookouts = Mitigation Effectiveness x
Model-Estimated Impacts
The marine mammals sighted by Lookouts during implementation of
mitigation in the range to PTS, as calculated by the equation above,
would avoid being exposed to these higher level impacts. To quantify
the number of marine mammals predicted to be sighted by Lookouts during
implementation of procedural mitigation in the range to mortality
during events using explosives, the species sightability is multiplied
by the mitigation effectiveness scores and number of model-estimated
mortality impacts, as shown in equation 1 above. The marine mammals
predicted to be sighted by Lookouts during implementation of procedural
mitigation in the range to mortality, as calculated by the above
equation 2, are predicted to avoid exposure in these ranges. The Navy
corrects the category of predicted impact for the number of animals
sighted within the mitigation zone, but does not modify the total
number of animals predicted to experience impacts from the scenario.
For example, the number of animals sighted (i.e., number of animals
that will avoid mortality) is first subtracted from the model-predicted
mortality impacts, and then added to the model-predicted injurious
impacts.
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. For additional
information on the quantitative analysis process and mitigation
measures, refer to the technical report titled Quantifying Acoustic
Impacts on Marine Mammals and Sea Turtles: Methods and Analytical
Approach for Phase III Training and Testing report (U.S. Department of
the Navy, 2018) and Chapter 6 (Take Estimates for Marine Mammals) and
Chapter 11 (Mitigation Measures) of the Navy's rulemaking/LOA
application.
In summary, we believe the Navy's methods, including the method for
incorporating mitigation and avoidance, are the most appropriate
methods for predicting PTS and TTS. 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 incur either TTS or PTS.
Summary of Requested Take From Training and Testing Activities
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 animal 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 their rules since 2009 and
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 (animal movement) 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 Navy Marine Species Density Database, 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 AMAPPS, 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.
Based on the methods discussed in the previous sections and the
Navy's model and the quantitative assessment of mitigation, the Navy
provided its take request for acoustic and explosive sources for
training and testing activities both annually (based on the maximum
number of activities per 12-month period) and over a 5-year period.
NMFS has reviewed the Navy's data and analysis and determined that it
is complete and accurate and that the takes by harassment as well as
the takes by serious injury or mortality from explosives requested for
authorization are reasonably expected to occur and that the takes by
serious injury or mortality could occur as a result of vessel strikes.
Five-year total impacts may be less than the sum total of each year
because although the annual estimates are based on the maximum
estimated takes, five-year estimates are based on the sum of two
maximum years and three nominal years.
[[Page 66939]]
Authorized Take From Training Activities
For training activities, Table 41 summarizes the Navy's take
request and the maximum amount and type of Level A and Level B
harassment that NMFS concurs is reasonably likely to occur by species
or stock. Authorized mortality is addressed further below. Navy Figures
6-12 through 6-50 in Chapter 6 of the Navy's rulemaking/LOA application
illustrate the comparative amounts of TTS and Level B behavioral
harassment for each species, noting that if a ``taken'' animat was
exposed to both TTS and Level B behavioral harassment, it was recorded
as a TTS.
Table 41--Species and Stock-Specific Take From Acoustic and Explosive Effects for All Training Activities in the
HSTT Study Area
----------------------------------------------------------------------------------------------------------------
Annual 5-Year total **
---------------------------------------------------------------
Species Stock Level B Level A Level B Level A
harassment harassment harassment harassment
----------------------------------------------------------------------------------------------------------------
Suborder Mysticeti (baleen whales)
----------------------------------------------------------------------------------------------------------------
Family Balaenopteridae (rorquals)
----------------------------------------------------------------------------------------------------------------
Blue whale *.................. Central North 34 0 139 0
Pacific.
Eastern North 1,155 1 5,036 3
Pacific.
Bryde's whale [dagger]........ Eastern Tropical 27 0 118 0
Pacific.
Hawaii [dagger]. 105 0 429 0
Fin whale *................... CA/OR/WA........ 1,245 0 5,482 0
Hawaii.......... 33 0 133 0
Humpback whale [dagger]....... CA/OR/WA 1,254 1 5,645 3
[dagger].
Central North 5,604 1 23,654 6
Pacific.
Minke whale................... CA/OR/WA........ 649 1 2,920 4
Hawaii.......... 3,463 1 13,664 2
Sei whale *................... Eastern North 53 0 236 0
Pacific.
Hawaii.......... 118 0 453 0
----------------------------------------------------------------------------------------------------------------
Family Eschrichtiidae
----------------------------------------------------------------------------------------------------------------
Gray whale [dagger]........... Eastern North 2,751 5 11,860 19
Pacific.
Western North 4 0 14 0
Pacific
[dagger].
----------------------------------------------------------------------------------------------------------------
Suborder Odontoceti (toothed whales)
----------------------------------------------------------------------------------------------------------------
Family Physeteridae (sperm whale)
----------------------------------------------------------------------------------------------------------------
Sperm whale *................. CA/OR/WA........ 1,397 0 6,257 0
Hawaii.......... 1,714 0 7,078 0
----------------------------------------------------------------------------------------------------------------
Family Kogiidae (sperm whales)
----------------------------------------------------------------------------------------------------------------
Dwarf sperm whale............. Hawaii.......... 13,961 35 57,571 148
Pygmy sperm whale............. Hawaii.......... 5,556 16 22,833 64
Kogia whales.................. CA/OR/WA........ 6,012 23 27,366 105
----------------------------------------------------------------------------------------------------------------
Family Ziphiidae (beaked whales)
----------------------------------------------------------------------------------------------------------------
Baird's beaked whale.......... CA/OR/WA........ 1,317 0 6,044 0
Blainville's beaked whale..... Hawaii.......... 3,687 0 16,364 0
Cuvier's beaked whale......... CA/OR/WA........ 7,016 0 33,494 0
Hawaii.......... 1,235 0 5,497 0
Longman's beaked whale........ Hawaii.......... 13,010 0 57,172 0
Mesoplodon spp................ CA/OR/WA........ 3,778 0 18,036 0
----------------------------------------------------------------------------------------------------------------
Family Delphinidae (dolphins)
----------------------------------------------------------------------------------------------------------------
Bottlenose dolphin............ California 214 0 876 0
Coastal.
CA/OR/WA 31,986 2 142,966 9
Offshore.
Hawaii Pelagic.. 2,086 0 9,055 0
Kauai & Niihau.. 74 0 356 0
Oahu............ 8,186 1 40,918 7
4-Island........ 152 0 750 0
Hawaii Island... 42 0 207 0
False killer whale [dagger]... Hawaii Pelagic.. 701 0 3,005 0
Main Hawaiian 405 0 1,915 0
Islands Insular
[dagger].
Northwestern 256 0 1,094 0
Hawaiian
Islands.
Fraser's dolphin.............. Hawaii.......... 28,409 1 122,784 3
Killer whale.................. Eastern North 73 0 326 0
Pacific
Offshore.
Eastern North 135 0 606 0
Pacific
Transient/West
Coast Transient.
Hawaii.......... 84 0 352 0
[[Page 66940]]
Long-beaked common dolphin.... California...... 128,994 14 559,540 69
Melon-headed whale............ Hawaiian Islands 2,335 0 9,705 0
Kohala Resident. 182 0 913 0
Northern right whale dolphin.. CA/OR/WA........ 56,820 8 253,068 40
Pacific white-sided dolphin... CA/OR/WA........ 43,914 3 194,882 12
Pantropical spotted dolphin... Hawaii Island... 2,585 0 12,603 0
Hawaii Pelagic.. 6,809 0 29,207 0
Oahu............ 4,127 0 20,610 0
4-Island........ 260 0 1,295 0
Pygmy killer whale............ Hawaii.......... 5,816 0 24,428 0
Tropical........ 471 0 2,105 0
Risso's dolphin............... CA/OR/WA........ 76,276 6 338,560 30
Hawaii.......... 6,590 0 28,143 0
Rough-toothed dolphin......... Hawaii.......... 4,292 0 18,506 0
NSD \1\......... 0 0 0 0
Short-beaked common dolphin... CA/OR/WA........ 932,453 45 4,161,283 216
Short-finned pilot whale...... CA/OR/WA........ 990 1 4,492 5
Hawaii.......... 8,594 0 37,077 0
Spinner dolphin............... Hawaii Island... 89 0 433 0
Hawaii Pelagic.. 3,138 0 12,826 0
Kauai & Niihau.. 310 0 1,387 0
Oahu & 4-Island. 1,493 1 7,445 5
Striped dolphin............... CA/OR/WA........ 119,219 1 550,936 3
Hawaii.......... 5,388 0 22,526 0
----------------------------------------------------------------------------------------------------------------
Family Phocoenidae (porpoises)
----------------------------------------------------------------------------------------------------------------
Dall's porpoise............... CA/OR/WA........ 27,282 137 121,256 634
----------------------------------------------------------------------------------------------------------------
Suborder Pinnipedia
----------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals)
----------------------------------------------------------------------------------------------------------------
California sea lion........... U.S............. 69,543 90 327,136 447
Guadalupe fur seal *.......... Mexico.......... 518 0 2,386 0
Northern fur seal............. California...... 9,786 0 44,017 0
----------------------------------------------------------------------------------------------------------------
Family Phocidae (true seals)
----------------------------------------------------------------------------------------------------------------
Harbor seal................... California...... 3,119 7 13,636 34
Hawaiian monk seal *.......... Hawaii.......... 139 1 662 3
Northern elephant seal........ California...... 38,169 72 170,926 349
----------------------------------------------------------------------------------------------------------------
Note: Kogia: Pygmy and dwarf sperm whales are difficult to distinguish between at sea, and abundance estimates
are only available for Kogia spp (reported in Barlow 2016 and Carretta et al. 2017). Due to low estimated
abundances of CA/OR/WA dwarf sperm whales, the majority of Kogia in the HSTT Study Area are anticipated to be
CA/OR/WA pygmy sperm whales.
Mesoplodon: No methods are available to distinguish between the six species of Mesoplodon beaked whales in 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 (Carretta et al.,
2018). These six species are managed as one unit.
* ESA-listed species (all stocks) within the HSTT Study Area.
** 5-year total impacts may be less than sum total of each year. Not all activities occur every year; some
activities occur multiple times within a year; and some activities only occur a few times over course of a 5-
year period.
[dagger] Only designated stocks are ESA-listed.
\1\ NSD: No stock designation.
Authorized Take From Testing Activities
For testing activities, Table 42 summarizes the Navy's take request
and the maximum amount and type of take by Level A and Level B
harassment that NMFS concurs is reasonably likely to occur and has
authorized by species or stock. Navy Figures 6-12 through 6-50 in
Chapter 6 of the Navy's rulemaking/LOA application illustrate the
comparative amounts of TTS and Level B behavioral harassment for each
species, noting that if a ``taken'' animat was exposed to both TTS and
Level B behavioral harassment in the model, it was recorded as a TTS.
[[Page 66941]]
Table 42--Species and Stock-Specific Take From Acoustic and Explosive Sound Source Effects for All Testing
Activities in the HSTT Study Area
----------------------------------------------------------------------------------------------------------------
Annual 5-year total **
---------------------------------------------------------------
Species Stock Level B Level A Level B Level A
harassment harassment harassment harassment
----------------------------------------------------------------------------------------------------------------
Suborder Mysticeti (baleen whales)
----------------------------------------------------------------------------------------------------------------
Family Balaenopteridae (rorquals)
----------------------------------------------------------------------------------------------------------------
Blue whale *.................. Central North 14 0 65 0
Pacific.
Eastern North 833 0 4,005 0
Pacific.
Bryde's whale [dagger]........ Eastern Tropical 14 0 69 0
Pacific.
Hawaii [dagger]. 41 0 194 0
Fin whale *................... CA/OR/WA........ 980 1 4,695 3
Hawaii.......... 15 0 74 0
Humpback whale [dagger]....... CA/OR/WA 740 0 3,508 0
[dagger].
Central North 3,522 2 16,777 11
Pacific.
Minke whale................... CA/OR/WA........ 276 0 1,309 0
Hawaii.......... 1,467 1 6,918 4
Sei whale *................... Eastern North 26 0 124 0
Pacific.
Hawaii.......... 49 0 229 0
----------------------------------------------------------------------------------------------------------------
Family Eschrichtiidae
----------------------------------------------------------------------------------------------------------------
Gray whale [dagger]........... Eastern North 1,920 2 9,277 7
Pacific.
Western North 2 0 11 0
Pacific
[dagger].
----------------------------------------------------------------------------------------------------------------
Suborder Odontoceti (toothed whales)
----------------------------------------------------------------------------------------------------------------
Family Physeteridae (sperm whale)
----------------------------------------------------------------------------------------------------------------
Sperm whale *................. CA/OR/WA........ 1,096 0 5,259 0
Hawaii.......... 782 0 3,731 0
----------------------------------------------------------------------------------------------------------------
Family Kogiidae (sperm whales)
----------------------------------------------------------------------------------------------------------------
Dwarf sperm whale............. Hawaii.......... 6,459 29 30,607 140
Pygmy sperm whale............. Hawaii.......... 2,595 13 12,270 60
Kogia whales.................. CA/OR/WA........ 3,120 15 14,643 67
----------------------------------------------------------------------------------------------------------------
Family Ziphiidae (beaked whales)
----------------------------------------------------------------------------------------------------------------
Baird's beaked whale.......... CA/OR/WA........ 727 0 3,418 0
Blainville's beaked whale..... Hawaii.......... 1,698 0 8,117 0
Cuvier's beaked whale......... CA/OR/WA........ 4,484 1 21,379 20
Hawaii.......... 561 0 2,675 0
Longman's beaked whale........ Hawaii.......... 6,223 0 29,746 0
Mesoplodon spp................ CA/OR/WA........ 2,415 1 11,512 11
----------------------------------------------------------------------------------------------------------------
Family Delphinidae (dolphins)
----------------------------------------------------------------------------------------------------------------
Bottlenose dolphin............ California 1,595 0 7,968 0
Coastal.
CA/OR/WA 23,436 1 112,410 4
Offshore.
Hawaii Pelagic.. 1,242 0 6,013 0
Kauai & Niihau.. 491 0 2,161 0
Oahu............ 475 0 2,294 0
4-Island........ 207 0 778 0
Hawaii Island... 38 0 186 0
False killer whale [dagger]... Hawaii Pelagic.. 340 0 1,622 0
Main Hawaiian 184 0 892 0
Islands Insular
[dagger].
Northwestern 125 0 594 0
Hawaiian
Islands.
Fraser's dolphin.............. Hawaii.......... 12,664 1 60,345 6
Killer whale.................. Eastern North 34 0 166 0
Pacific
Offshore.
Eastern North 64 0 309 0
Pacific
Transient/West
Coast Transient.
Hawaii.......... 40 0 198 0
Long-beaked common dolphin.... California...... 118,278 6 568,020 24
Melon-headed whale............ Hawaiian Islands 1,157 0 5,423 0
Kohala Resident. 168 0 795 0
Northern right whale dolphin.. CA/OR/WA........ 41,279 3 198,917 15
Pacific white-sided dolphin... CA/OR/WA........ 31,424 2 151,000 8
Pantropical spotted dolphin... Hawaii Island... 1,409 0 6,791 0
Hawaii Pelagic.. 3,640 0 17,615 0
Oahu............ 202 0 957 0
[[Page 66942]]
4-Island........ 458 0 1,734 0
Pygmy killer whale............ Hawaii.......... 2,708 0 13,008 0
Tropical........ 289 0 1,351 0
Risso's dolphin............... CA/OR/WA........ 49,985 3 240,646 16
Hawaii.......... 2,808 0 13,495 0
Rough-toothed dolphin......... Hawaii.......... 2,193 0 10,532 0
NSD \1\......... 0 0 0 0
Short-beaked common dolphin... CA/OR/WA........ 560,120 44 2,673,431 216
Short-finned pilot whale...... CA/OR/WA........ 923 0 4,440 0
Hawaii.......... 4,338 0 20,757 0
Spinner dolphin............... Hawaii Island... 202 0 993 0
Hawaii Pelagic.. 1,396 0 6,770 0
Kauai & Niihau.. 1,436 0 6,530 0
Oahu & 4-Island. 331 0 1,389 0
Striped dolphin............... CA/OR/WA........ 56,035 2 262,973 11
Hawaiian........ 2,396 0 11,546 0
----------------------------------------------------------------------------------------------------------------
Family Phocoenidae (porpoises)
----------------------------------------------------------------------------------------------------------------
Dall's porpoise............... CA/OR/WA........ 17,091 72 81,611 338
----------------------------------------------------------------------------------------------------------------
Suborder Pinnipedia
----------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals)
----------------------------------------------------------------------------------------------------------------
California sea lion........... U.S............. 48,665 6 237,870 23
Guadalupe fur seal *.......... Mexico.......... 939 0 4,357 0
Northern fur seal............. California...... 5,505 1 26,168 4
----------------------------------------------------------------------------------------------------------------
Family Phocidae (true seals)
----------------------------------------------------------------------------------------------------------------
Harbor seal................... California...... 2,325 1 11,258 7
Hawaiian monk seal *.......... Hawaii.......... 66 0 254 0
Northern elephant seal........ California...... 22,702 27 107,343 131
----------------------------------------------------------------------------------------------------------------
Note: Kogia: Pygmy and dwarf sperm whales are difficult to distinguish between at sea, and abundance estimates
are only available for Kogia spp (reported in Barlow 2016 and Carretta et al. 2017). Due to low estimated
abundances of CA/OR/WA dwarf sperm whales, the majority of Kogia in the HSTT Study Area are anticipated to be
CA/OR/WA pygmy sperm whales.
Mesoplodon: No methods are available to distinguish between the six species of Mesoplodon beaked whales in 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 (Carretta et al.,
2018). These six species are managed as one unit.
* ESA-listed species (all stocks) within the HSTT Study Area.
** 5-year total impacts may be less than sum total of each year. Not all activities occur every year; some
activities occur multiple times within a year; and some activities only occur a few times over course of a 5-
year period.
[dagger] Only designated stocks are ESA-listed.
\1\ NSD: No stock designation.
Take From Vessel Strikes and Explosives by Serious Injury or Mortality
Vessel Strike
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
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; Lemon et al., 2006;
Lusseau, 2003; Lusseau, 2006; Magalhaes et al., 2002; Nowacek et al.,
2001; Richter et al., 2003; Scheidat et al., 2004; Simmonds, 2005;
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 that the Navy is
[[Page 66943]]
conducting training or testing activities using active sonar or
explosives.
The most vulnerable marine mammals 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), 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:
[ssquf] Many military ships have their bridges positioned closer
to the bow, offering better visibility ahead of the ship (compared
to a commercial merchant vessel).
[ssquf] 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.
[ssquf] 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.
[ssquf] 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 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 Lookouts, beyond those already stationed on the bridge
and on navigation teams, are positioned as Lookouts during some
training events.
[ssquf] 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 HSTT Study Area or while in transit.
There have been two recorded Navy vessel strikes of large whales in
the HSTT Study Area from 2009 through 2018, the period in which Navy
began implementing effective mitigation measures to reduce the
likelihood of vessel strikes. Both strikes occured in 2009 and both
were to fin whales. In order to account for the accidental nature of
vessel strikes to large whales in general, and the potential risk from
any vessel movement within the HSTT Study Area within the five-year
period in particular, the Navy requested incidental takes based on
probabilities derived from a Poisson distribution using ship strike
data between 2009-2016 in the HSTT Study Area (the time period from
when current mitigations were instituted until the Navy conducted the
analysis for the EIS/OEIS and rulemaking/LOA application; no new
strikes have occurred since), as well as historical at-sea days in the
HSTT Study Area from 2009-2016 and estimated potential at-sea days for
the period from 2018 to 2023 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 2018 to 2023. The
analysis is described in detail in Chapter 6 of the Navy's rulemaking/
LOA application (and further refined in the Navy's revised ship strike
analysis posted on NMFS' website https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities).
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 (which has
occasionally occurred). 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 fin whale strikes in their calculations to
determine the number of strikes likely to result from their activities
(although worldwide strike information, from all Navy activities and
other strikes, was used to inform the species that may be struck) and
evaluated data beginning in 2009, as that was the start of the Navy's
Marine Species Awareness Training and adoption of additional mitigation
measures to address ship strike, which will remain in place along with
additional mitigation measures during the five years of this rule.
The probability analysis concluded that there was a 29 percent
chance that zero whales would be struck by Navy vessels over the five-
year period, indicating a 71 percent chance that at least one whale
would be struck over the five years and a 10 percent chance of striking
three whales over the five-year period. Therefore, the Navy estimates,
and NMFS agrees, that there is some probability 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 HSTT
Study Area over the course of the five years.
Small delphinids, porpoises, and pinnipeds are neither expected nor
authorized 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 crew, etc.), 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 being struck by a vessel as a
result of Navy activities
[[Page 66944]]
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. Based on this information, NMFS concurs with the
Navy's assessment and recognizes the potential for (and is authorizing)
incidental take by vessel strike of large whales only (i.e., no
dolphins, small whales, porpoises, or pinnipeds) over the course of the
five-year regulations from training and testing activities as discussed
below.
For large whales, the Navy's application identified the
distribution of species over which the take request would apply based
on the species/stocks most likely to be present in the HSTT Study Area
based on documented abundance and where overlap occurs between a
species' distribution and core Navy training and testing areas within
the HSTT Study Area. To determine which species may be struck, the Navy
used a weight of evidence approach to qualitatively rank range complex
specific species using historic and current stranding data from NMFS,
relative abundance as derived by NMFS for the HSTT Biological Opinion,
and the Navy-funded monitoring data within each range complex. Results
of this approach are presented in Table 5-4 of the Navy's rulemaking/
LOA application.
Based on the analysis described above and in its application, the
Navy estimated that it has the potential to strike, and take by serious
injury or mortality, up to three large whales incidental to the
specified activity over the course of the five years of the HSTT
regulations. The Navy initially requested incidental take authorization
for up to two of any the following stocks in the five-year period: gray
whale (Eastern North Pacific stock), fin whale (CA/OR/WA stock),
humpback whale (CA/OR/WA stock, Mexico DPS), humpback whale (Central
North Pacific stock), and sperm whale (Hawaii stock). The Navy also
initially requested incidental take authorization for one of any the
following species over the five-year period: blue whale (Eastern North
Pacific stock), Bryde's whale (Eastern Tropical Pacific stock), Bryde's
whale (Hawaii stock), humpback whale (CA/OR/WA stock, Central America
DPS), minke whale (CA/OR/WA stock), minke whale (Hawaii stock), sperm
whale (CA/OR/WA stock), sei whale (Hawaii stock), and sei whale
(Eastern North Pacific stock).
NMFS independently reviewed this analysis and agrees that three
ship strikes have at least the potential to occur and, therefore, that
the request for mortal takes of three large whales over the five-year
period of the rule is reasonable based on the available strike data
(two strikes by Navy over approximately 10 years) and the Navy's
probability analysis. Based on the reasons described below, however,
NMFS does not agree that two mortal takes of humpback whale (CA/OR/WA
stock) or sperm whales are likely, or that any strike of the following
whale species is remotely likely: Minke whale (CA/OR/WA stock), minke
whale (Hawaii stock), sei whale (Hawaii stock), sei whale (Eastern
North Pacific stock), Bryde's whale (Eastern Tropical Pacific stock),
sperm whale (CA/OR/WA stock) and Bryde's whale (Hawaii stock).
Since the proposed rule was published, NMFS and the Navy re-
examined and re-analyzed the available information regarding how many
of any given stock could be struck and should be authorized for lethal
take. As noted in the proposed rule, the Navy initially considered a
weight of evidence approach that considered relative abundance,
historical strike data over many years, and the overlap of Navy
activities with the stock distribution in their request. Since the
proposed rule, NMFS and the Navy further discussed the available
information and considered two factors in addition to those considered
in the Navy's additional 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 and (2) whether the Navy has
ever definitively struck an individual from a particular stock and, if
so, how many times.
To address number (1) above, NMFS compiled information from NMFS'
SARs on detected annual rates of large whale serious injury and
mortality from vessel collisions. The annual rates of large whale
serious injury and mortality from vessel collisions from the SARs help
inform the relative susceptibility of large whale species to vessel
strike in SOCAL and Hawaii as recorded systematically over the last
five years. We summed the annual rates of mortality and serious injury
from vessel collisions as reported in the SARs, then divided each
species' annual rate by this sum to get the relative likelihood. To
estimate the percent likelihood of striking a particular species of
large whale, we multiplied the relative likelihood of striking each
species by the total probability of striking a whale (i.e., 71 percent,
as described by the Navy's probability analysis above). We also
calculated the percent likelihood of striking a particular species of
large whale twice by squaring the value estimated for the probability
of striking a particular species of whale once (i.e., to calculate the
probability of an event occurring twice, multiply the probability of
the first event by the second). We note that these probabilities vary
from year to year as the average annual mortality for a given five-year
window changes (and we include the annual averages from 2017 and 2018
SARs in Table 43 to illustrate), however, over the years and through
changing SARs, stocks tend to consistently maintain a relatively higher
or relatively lower likelihood of being struck.
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 HSTT Study Area since 1991 (since they
started tracking consistently), as well as the information originally
considered by the Navy in their application, which includes relative
abundance, total recorded strikes, and the overlay of all of this
information with the Navy's action area. We note that for all of the
mortal take of species specifically denoted in Table 43 below, 19
percent of the individuals struck overall by any vessel type remained
unidentified and 36 percent of those struck by the Navy (5 of 14 in the
Pacific) remained unidentified. However, given the information on known
stocks struck, the analysis below remains appropriate. 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 and 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 43 includes the percent likelihood
of hitting an individual whale once based on SAR data, total strikes
from Navy vessels and from all other vessels, relative abundance, and
modeled vessel strikes from Rockwood et al. The last column indicates
the annual mortality authorized: those stocks with one M/SI take
authorized over the five-year period of the rule are shaded lightly,
while those with two M/SI takes authorized
[[Page 66945]]
over the five-year period of the rule are shaded more darkly.
[GRAPHIC] [TIFF OMITTED] TR27DE18.025
Accordingly, stocks that have no record of ever having been struck
by any vessel are considered unlikely to be struck by the Navy in the
five-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 percent
likelihood based on the SAR calculation and a low relative abundance
are also considered unlikely to be struck by the Navy during the five-
year rule. We note that while vessel strike records have not
differentiated between Eastern North Pacific and Western North Pacific
gray whales, given their small population size and the comparative
rarity with which individuals from the Western North Pacific stock are
detected off the U.S. West Coast, it is highly unlikely that they would
be encountered, much less struck. This rules out all but six stocks.
Three of the six stocks (CA/OR/WA stock of fin whale, Eastern North
Pacific stock of gray whale, and Central North Pacific stock of
humpback whale) are the only stocks to have been hit more than one time
each by the Navy in the HSTT StudyAarea, have the three highest total
strike records (21, 35, and 58 respectively), have three of the four
highest percent likelihoods based on the SAR records, have three of the
four significantly higher relative abundances, and have up to a 3 or 4
percent likelihood of being struck twice based on NMFS' SAR calculation
(not shown in Table 43, but proportional to percent likelihood of being
struck once). Based on all of these factors, it is considered
reasonably likely that these stocks could be struck twice during the
five-year rule.
Based on the information summarized in Table 43 and the fact that
we expect three large whales could be struck, it is considered
reasonably likely that one individual from the remaining three stocks
could be struck. Sperm whales have only been struck a total of two
times by any vessel type in the whole HSTT Study Area, however, the
Navy struck a sperm whale once in Hawaii prior to 2009 and the relative
abundance of sperm whales in Hawaii is the highest of any of the stocks
present. Therefore, we consider it reasonably likely that the Hawaii
stock of sperm whales could be struck once during the five-year rule.
The total strikes of Eastern North Pacific blue whales, the percent
likelihood of striking one based on the SAR calculation, and their
relative abundance can all be considered moderate compared to other
stocks and the Navy has struck one in the past prior to 2009 (with the
likelihood of striking two based on the SAR calculation being below one
percent). Therefore, we consider it reasonably likely that the Navy
could strike one individual over the course of the five-year rule. The
Navy has not hit a humpback whale in the HSTT Study Area and their
relative abundance is very low. However, the Navy has struck a humpback
whale in the Northwest and as a species, humpbacks have a moderate to
high number of total strikes and percent likelihood of being struck.
Although the likelihood of CA/OR/WA humpback whales being struck
overall is moderate to high relative to other stocks, the distribution
of the Mexico DPS versus the Central America DPS, as well as the
distribution of overall vessel strikes inside versus outside of the
SOCAL area (the majority are outside), supports the reasonable
likelihood that the Navy could strike one individual humpback whale
(not two), and that that
[[Page 66946]]
individual would be highly likely to be from the Mexico DPS, as
described below.
Specifically, regarding the likelihood of striking a humpback whale
from a particular DPS, as suggested in Wade et al. (2016), the
probability of encountering (which is thereby applied to striking)
humpback whales from each DPS in the CA/OR area is 89.6 percent and
19.7 percent for the Mexico and Central America DPSs, respectively
(note that these percentages reflect the upper limit of the 95 percent
confidence interval to reduce the likelihood of underestimating take,
and thereby do not total to 100). This suggests that the chance of
striking a whale from the Central America DPS is one tenth to one fifth
of the overall chance of hitting a CA/OR/WA humpback whale in general
in the SOCAL part of the HSTT Study Area, which in combination with the
fact that no humpback whale has been struck in SOCAL makes it highly
unlikely, and thereby none from the Central America DPS are anticipated
or authorized. If a humpback whale were struck in SOCAL, it is likely
it would be of the Mexico DPS. However, regarding the overall
likelihood of striking a humpback whale at all and the likely number of
times, we note that the majority of strikes of the CA/OR/WA humpback
whale (i.e., the numbers reflected in Table 43) take place outside of
SOCAL and, whereas the comparative DPS numbers cited above apply in the
California and Oregon feeding area, in the Washington and Southern
British Columbia feeding area, Wade et al. (2016) suggest that 52.9,
41.9, and 14.7 percent of humpback whales encountered will come from
the Hawaii, Mexico, and Central America DPSs, respectively. This means
that the numbers in Table 43 indicating the overall strikes of CA/OR/WA
humpback whales and SAR calculations based on average annual mortality
over the last five years are actually lower than indicated for the
Mexico DPS, which would only be a subset of those mortalities. Last,
the Rockwood et al. paper supports a relative likelihood of 1:1:2 for
striking blue whales, humpback whales, and fin whales off the U.S. West
Coast, which supports the authorized take included in this rule, which
is 1, 1, and 2, respectively over the five-year period. For these
reasons, one mortal take of CA/OR/WA humpback whales, which would be
expected to be of the Mexico DPS, could reasonably likely occur and is
authorized.
Accordingly, the Navy revised their request for take by serious
injury or mortality to include up to two of any the following species
in the five-year period: Gray whale (Eastern North Pacific stock), fin
whale (CA/OR/WA stock), humpback whale (Central North Pacific stock);
and one of any of the following species in the five year period: Blue
whale (Eastern North Pacific stock), humpback whale (CA/OR/WA stock,
Mexico DPS), or sperm whale (Hawaii stock).
As described above, NMFS and the Navy concur that vessel strikes to
the stocks below are very unlikely to occur due to the stocks'
relatively low occurrence in the HSTT Study Area, particularly in core
HSTT training and testing subareas, and the fact that the stocks have
not been struck by the Navy and are rarely, if ever, recorded struck by
other vessels. Therefore the Navy is not requesting lethal take
authorization, and NMFS is not authorizing lethal take, for the
following stocks: Bryde's whale (Eastern Tropical Pacific stock),
Bryde's whale (Hawaii stock), humpback whale (CA/OR/WA stock, Central
America DPS), minke whale (CA/OR/WA stock), minke whale (Hawaii stock),
sei whale (Hawaii stock), sei whale (Eastern North Pacific stock), and
sperm whale (CA/OR/WA stock).
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 could be taken by
serious injury or mortality over the five-year period of the rule, and
that those three whales may include no more than two of any of the
following stocks: Gray whale (Eastern North Pacific stock), fin whale
(CA/OR/WA stock), humpback whale (Central North Pacific stock); and no
more than one of any of the following stocks: Blue whale (Eastern North
Pacific stock), humpback whale (CA/OR/WA, Mexico DPS), and sperm whale
(Hawaii stock). Accordingly, NMFS has evaluated under the negligible
impact standard the serious injury or mortality of 0.2 or 0.4 whales
annually from each of these species or stocks (i.e., 1 or 2 takes,
respectively, divided by 5 years to get the annual number), along with
other expected harassment incidental take.
Explosives
The Navy's model and quantitative analysis process used for the
HSTT FEIS/OEIS and in the Navy's rulemaking/LOA application to estimate
potential exposures of marine mammals to explosive stressors is
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 report (U.S. Department of the Navy,
2018). Specifically, over the course of a year, the Navy's model and
quantitative analysis process estimates mortality of two short-beaked
common dolphin and one California sea lion as a result of exposure to
explosive training and testing activities (please refer to section 6 of
the Navy's rule making/LOA application). Over the five[hyphen]year
period of the regulations requested, mortality of 10 marine mammals in
total (6 short-beaked common dolphins and 4 California sea lions) is
estimated as a result of exposure to explosive training and testing
activities. NMFS coordinated with the Navy in the development of their
take estimates and concurs with the Navy's approach for estimating the
number of animals from each species that could be affected by mortality
takes from explosives.
Mitigation Measures
Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the
``permissible methods of taking pursuant to such activity, and other
means of effecting the least practicable adverse impact on such species
or stock and its habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance, and on the
availability of such species or stock for subsistence uses'' (``least
practicable adverse impact''). NMFS does not have a regulatory
definition for least practicable adverse impact. The NDAA for FY 2004
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'' 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] satisfies] the statutory `least
practicable adverse impact' requirement with a `negligible impact'
finding.'' More recently, 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
[[Page 66947]]
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, and expands upon, previous rules we
have issued, such as the Navy Gulf of Alaska rule (82 FR 19530; April
27, 2017) and the Navy Atlantic Fleet Testing and Training rule (83 FR
57076; November 14, 2018).
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 \3\ and, therefore are considered in
evaluating population level impacts.
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\3\ A growth rate can be positive, negative, or flat.
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As we stated in the preamble to the final rule for the 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. [T]he 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
such species or stock and its 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.\4\
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\4\ For purposes of this discussion, we omit reference to the
language in the standard for least practicable adverse impact that
says we also must mitigate for subsistence impacts because they are
not at issue in this regulation.
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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). 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 (16 U.S.C. 1362(11)). 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, the term ``stock'' in the MMPA is interchangeable with the
statutory term ``population stock.'' 16 U.S.C. 1362(11). 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's statutory
findings for enacting the MMPA, nearly all of which are most applicable
at the species or stock (i.e., population) level. See 16 U.S.C. 1361
(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 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 affect the least practicable amount of adverse
impact upon the affected species or stock.
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 and their habitat. 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, we reiterate that 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.\5\
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\5\ 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).
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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
[[Page 66948]]
military readiness needs.'' Id. 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.
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 a
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). 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
(2) The practicability of the measures for applicant
implementation. Practicability of implementation may consider such
things as cost, impact on 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. 16 U.S.C. 1371(a)(5)(A)(iii).
While the language of the least practicable adverse impact standard
calls for minimizing impacts to affected species or stocks and their
habitats, 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
environment, and the affected species or stocks. 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
that we had not previously considered, becomes available and
necessitates 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 firmly established 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), 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
their 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. 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 will be
carefully considered to determine the types of mitigation that are
appropriate under the least practicable adverse impact
[[Page 66949]]
standard. We discuss consideration of these factors in greater detail
below.
1. Reduction of adverse impacts to marine mammal species or stocks
and their habitat.\6\ 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.
---------------------------------------------------------------------------
\6\ We recognize the least practicable adverse impact standard
requires consideration of measures that will address minimizing
impacts on the availability of the species or stocks for subsistence
uses where relevant. Because subsistence uses are not implicated for
this action, we do not discuss them. However, a similar framework
would apply for evaluating those measures, taking into account the
MMPA's directive that we make a finding of no unmitigable adverse
impact on the availability of the species or stocks for taking for
subsistence, and the relevant implementing regulations.
---------------------------------------------------------------------------
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 16 U.S.C. 1362(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 nor 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,
personnel safety, practicality of implementation, and impact on the
effectiveness of the military readiness activity (16 U.S.C.
1371(a)(5)(A)(iii)).
Assessment of Mitigation Measures for HSTT Rule
NMFS reviewed the Specified Activities and the mitigation measures
as described in the Navy's rulemaking/LOA application and the HSTT
FEIS/OEIS to determine if they would result in the least practicable
adverse effect on marine mammals. 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 evaluation process used to develop, assess, and
select mitigation measures, which was coordinated with and informed by
input from NMFS and included consideration of the measures that were
added as a result of the settlement agreement (see below), can be found
in Chapter 5 (Mitigation) and Appendix K (Geographic Mitigation
Assessment) of the HSTT FEIS/OEIS and is summarized below in this
section. The process described in Chapter 5 (Mitigation) and Appendix K
(Geographic Mitigation Assessment) of the HSTT FEIS/OEIS robustly
supports NMFS' independent evaluation of whether the mitigation
measures required by this rule meet the least practicable adverse
impact standard. The Navy is required to implement the mitigation
measures identified in this rule to avoid or reduce potential impacts
from acoustic, explosive, and physical disturbance and ship strike
stressors.
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 proposal and 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). We note that in their application, the Navy added a
couple of mitigation measures that were new since the 2013-2018 HSTT
incidental take regulations: (1) The Santa Barbara Island Mitigation
Area--to avoid or reduce potential impacts from mid-frequency active
sonar and explosives on numerous marine mammal species (including blue
whales and gray whales) within the mitigation area, which contains
important foraging or migration habitat and overlaps a portion of the
Channel Islands National Marine Sanctuary, and (2) Blue Whale, Gray
Whale, and Fin Whale Awareness Notification Message Areas--to further
help avoid or reduce potential impacts from vessel strikes and training
and testing activities on blue whales, gray whales, and fin whales
within the Southern California portion of the Study Area, which
contains important seasonal foraging or migration habitat for these
species. However, it is still necessary for NMFS to consider whether
there are additional practicable measures that could also contribute to
the reduction of adverse effects on the species or stocks through
effects on annual rates of recruitment or survival. In the case of the
Navy's HSTT application, we worked with the Navy
[[Page 66950]]
prior to the publication of the proposed rule and ultimately, the Navy
agreed to significantly expand geographic mitigation areas adjacent to
the island of Hawaii to more fully encompass the Alenuihaha Channel
(important habitat and migration area) and overlap the BIAs of multiple
species (reproductive area for humpbacks, and overlapping the ranges of
multiple small resident populations of odontocetes) and to limit
additional anti-submarine warfare mid-frequency active sonar (ASW)
source bins (MF4) within those mitigation areas, which is expected to
further reduce the probability and severity of impacts that would be
more likely to affect reproduction or survival of individuals or
adversely affect the stock.
Of note, following publication of the 2013 HSTT incidental take
rule, the Navy and NMFS were sued and the parties reached a settlement
in Conservation Council for Hawaii v. National Marine Fisheries
Service, 97 F. Supp.3d 1210 (D. Haw. 2015), in which the Navy agreed to
restrict its activities within specific areas in the HSTT Study Area
(beyond the areas and restrictions included as mitigation measures in
the 2013 rule). Additional detail is provided below in the subsection
entitled Brief Comparison of Settlement Mitigation and Final HSTT
Mitigation in the Rule.
In summary (and as described in more detail below in this section),
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 or explosives, ship strike, and
impacts to marine mammal habitat. Specifically, the Navy will use a
combination of delayed starts, powerdowns, and shutdowns to minimize or
avoid serious injury or mortality, minimize the likelihood or severity
of PTS or other injury, and reduce instances of TTS or more severe
behavioral disruption caused by acoustic sources or explosives. The
Navy also will implement multiple time/area restrictions (several of
which have been added since the 2013 HSTT MMPA incidental take rule)
that would reduce take of marine mammals in areas or at times where
they are known to engage in important behaviors, such as feeding or
calving, 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.
Since publication of the proposed rule, NMFS and the Navy have
agreed to additional mitigation measures that are expected to reduce
the likelihood and/or severity of adverse impacts on marine species/
stocks and their habitat and are practicable for implementation. Below
we summarize the added measures and describe the manner in which they
are expected to reduce the likelihood or severity of adverse impacts on
marine mammal species or stocks and their habitat. A full description
of each measure is included in Tables 45-62.
1. Pre-event in-water explosive event observations--The Navy will
implement pre-event observation mitigation for all in-water explosive
event mitigation measures. Additionally, if there are other platforms
participating in these events and in the vicinity of the detonation
area, Navy personnel on those platforms will also visually observe this
area as part of the mitigation team. This added monitoring for a subset
of activities for which it was not previously required (explosive
bombs, missiles and rockets, projectiles, torpedoes, and grenades) in
advance of explosive events increases the likelihood that marine
mammals will be detected if they are in the mitigation area for that
event and that, if any animals are detected, explosions will be delayed
by timely mitigation implementation, thereby further reducing the
already low likelihood that animals will be injured or killed by the
blast.
2. Post-event in-water explosive event observations--The Navy will
implement post-event observation mitigation for all in-water explosive
event mitigation measures. Additionally, if there are other platforms
participating in these events and in the vicinity of the detonation
area, Navy personnel on those platforms will also visually observe this
area as part of the mitigation team. This added monitoring for a subset
of activities for which it was not previously required (explosive
bombs, missiles and rockets, projectiles, torpedoes, grenades)
increases the likelihood that any injured marine mammals would be
detected following an explosive event, which would increase our
understanding of impacts and could potentially inform mitigation
changes via the adaptive management provisions.
3. The San Diego Arc Mitigation Area was the initial mitigation
area for the proposed rule. For the final rule, the Navy agreed to add
the San Nicolas Island and Santa Monica/Long Beach Mitigation Areas
(June 1-October 31), which include all of the relatively small portions
of the Santa Monica Bay/Long Beach and San Nicolas Island BIAs that
overlap the HSTT Study Area (55.4 Nmi\2\ or 13.9 percent and 33.6
Nmi\2\ or 23.5 percent, respectively). The Navy agrees to limit
explosives during training in the Santa Monica Bay/Long Beach and San
Nicolas Island Mitigation Areas. This reduction of activities (as
described here and in the newly expanded measure immediately below,
i.e., fewer explosives and MF1 sonar) in these areas with higher
concentrations of blue whales engaged in important feeding behaviors is
expected to reduce the probability or severity of impacts on blue
whales that would be more likely to adversely affect the reproduction
or survival of any individual, which in turn reduces the likelihood
that any impacts would translate to adverse impacts on the stock.
4. The Navy agrees to limit surface ship sonar in the Santa Monica/
Long Beach and San Nicolas Island Mitigation Areas. The Navy will not
exceed 200 hrs of MFAS sensor MF1 from June 1 through October 31 in the
combined San Diego Arc, San Nicolas Island, and Santa Monica/Long Beach
Mitigation Areas (manner in which this helps reduce impact to marine
mammals noted directly above).
5. In the proposed rule, the Navy included a seasonal restriction
on the use of hull-mounted active sonar in the 4-Islands Mitigation
Area, but no limit on explosive use. The Navy has added an all-year
restriction on the use of explosives in this area. The 4-Islands
Mitigation Area overlaps with a reproductive BIA for humpback whales,
as well as BIAs for several small resident populations of multiple
odontocetes (bottlenose dolphins, main Hawaiian Island false killer
whales, pantropical spotted dolphins, and spinner dolphins). For
humpback whales, the reduction of activities in this area with
individuals that have calves or are potentially breeding is expected to
reduce the probability or severity of impacts that would be more likely
to adversely impact reproduction or survival of individuals by directly
interfering with breeding behaviors or by separating mothers and calves
at a time with calves are more susceptible to predators. For the
odontocete stocks with BIAs for small resident populations, we aim to
avoid overwhelming small populations (which are more susceptible to
certain population effects, such as Allee effects) with large scale
impacts, especially when the population is limited to a small area and
less able to access alternative habitat. Limiting explosive effects in
these mitigation areas that overlap the BIAs further reduces impacts to
these stocks, although we note that all four of these odontocete small
resident populations span multiple islands, which means that
[[Page 66951]]
impacts in any one location are less likely to affect the whole
population.
6. The Navy has agreed to issue notification messages to increase
operator awareness of the presence of marine mammals. The Navy will
review WhaleWatch, a program coordinated by NMFS' West Coast Region as
an additional information source to inform the drafting of the annual
notification messages for blue, fin, and gray whales in SOCAL.The
information will alert vessels to the possible presence of these stocks
to maintain safety of navigation and further reduce the potential for a
vessel strike. Any expanded mechanisms for detecting large whales,
either directly around a vessel or in the wider area to increase
vigilance for vessels, further reduce the probability that a whale will
be struck.
The Navy assessed the new and/or expanded measures it has agreed to
(above) 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 were supportable. As
described above, NMFS has independently evaluated all of the measures
the Navy has committed to (including those above added since the
proposed rule was published) in the manner described earlier in this
section (i.e., in consideration of their ability to reduce adverse
impacts on marine mammal species and stocks and their habitat and their
practicability for implementation). We have determined that the
additional measures will further reduce impacts on the affected marine
mammal species and stocks and their habitat beyond the initial measures
proposed and, further, be practicable for Navy implementation.
The Navy also evaluated numerous measures in the HSTT FEIS/OEIS
that were not included in the Navy's rulemaking/LOA application, and
NMFS independently reviewed and concurs with 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, Chapter
5 (Mitigation) of the HSTT FEIS/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 NGOs or the
public, through scoping or public comment on environmental compliance
documents. Appendix K (Geographic Mitigation Assessment) of the HSTT
FEIS/OEIS includes an in-depth analysis of time/area restrictions that
have been recommended over time or previously implemented as a result
of litigation. As described in Chapter 5 (Mitigation) of the HSTT FEIS/
OEIS, commenters sometimes recommend that the Navy reduce its overall
amount of training, reduce explosive use, modify its sound sources,
completely replace live training 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 the Navy has described in Chapter 5 (Mitigation) of the
HSTT FEIS/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 would 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 undermining of the effectiveness of training
and testing persuasive, and for these 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 HSTT FEIS/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 Chapter 5 Mitigation of HSTT FEIS/OEIS). NMFS
independently reviewed the Navy's evaluation and concurred 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 required under the least
practicable adverse impact standard.
Last, Appendix K (Geographic Mitigation Assessment) of the HSTT
FEIS/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 or stock 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 (e.g.,
including an assessment of the specific importance of that area for
training, considering proximity to training ranges and emergency
landing fields and other issues). The analysis analyzes an extensive
list of areas, including areas in which certain Navy activities were
limited under the terms of the 2015 HSTT settlement agreement, areas
identified by the California Coastal Commission, and areas suggested
during scoping. For the areas that were agreed to under the settlement
agreement, the Navy notes two important facts that NMFS generally
concurs with: (1) The measures were derived pursuant to negotiations
with plaintiffs and were specifically not evaluated or selected based
on the examination of the best available science that NMFS typically
applies to a mitigation assessment and (2) the Navy's adoption of
restrictions on its activities as part of a relatively short-term
settlement does not mean that those restrictions are practicable to
implement over the longer term.
The Navy proposed (and NMFS has incorporated into this rule)
several time/area mitigations that were not included in the 2013-2018
HSTT MMPA regulations (as described above). For the areas that are not
included in these regulations, though, the analysis in the HSTT FEIS/
OEIS (Chapter 5 and Appendix K) shows that on balance, the mitigation
was not warranted because the anticipated reduction of adverse impacts
on marine mammal species or stocks and their habitat was not sufficient
to offset the impracticability of implementation (in some cases
potential benefits to marine mammals were limited to non-existent, in
others the consequences on mission effectiveness were too great). We
note that in regard to the protection of marine mammal habitat, habitat
value is informed by marine mammal presence and use and, in some cases,
there may be overlap in measures that minimize impacts to the species
or stock directly and measures that minimize impacts on
[[Page 66952]]
habitat. In this rule, we have identified 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., blue
whale feeding areas in SOCAL, and in-shore small resident populations
of odontocetes around Hawaii). In addition to being delineated based on
physical features that drive habitat function (e.g., bathymetric
features, among others for some BIAs), the high densities and
concentration of certain important behaviors (e.g., feeding) in these
particular areas clearly indicate the presence of preferred habitat.
Overall, NMFS has independently reviewed the Navy's mitigation
analysis Chapter 5 (Mitigation) and Appendix K (Geographic Mitigation
Assessment) of the HSTT FEIS/OEIS as referenced above), which considers
the same factors that NMFS considers to satisfy the least practical
adverse impact standard, and concurs with the conclusions. Therefore,
NMFS is not including the additional measures discussed in the HSTT
FEIS/OEIS in these regulations, other than the new measures that were
discussed in the proposed rule and those agreed upon after publication
of the proposed rule, as described above. Below, we list and describe
the mitigation measures (organized into procedural measures and
mitigation areas) that NMFS has determined will ensure the least
practicable adverse impact on all affected species and stocks and their
habitat, including the specific considerations for military readiness
activities. However, first, in the section immediately below, we
provide a brief summary of the ways in which the mitigation included in
this rule compares to the mitigation the Navy implemented during the
settlement agreement.
Brief Comparison of 2015 Settlement Mitigation and Final HSTT
Mitigation in the Rule
As noted above, following publication of the 2013 HSTT MMPA
incidental take rule, the Navy and NMFS were sued and the parties
reached a settlement in 2015 under which the Navy agreed to restrict
its activities within specific areas in the HSTT Study Area (beyond the
areas and restrictions included in the 2013 rule). While we have
described above the analysis that supports the selection of mitigation
measures included in the final rule (referencing the associated Navy
documents, where appropriate), because the Navy has been implementing
the settlement agreement measures since 2015, we provide here a summary
description of the differences and additional analysis.
First, we note broadly that the provisional restrictions on
activities within the HSTT Study Area were derived pursuant to
negotiations with the plaintiffs as part of the lawsuit and
specifically were not evaluated or selected based on the best available
science as would occur through the MMPA rulemaking process or through
related analyses conducted under the National Environmental Policy Act
(NEPA) or the ESA. The agreement did not constitute a concession by the
Navy as to the impacts of Navy activities on marine mammals or any
other marine species, the extent to which the measures would reduce
impacts, or the practicability of the measures. The Navy's adoption of
restrictions on its HSTT testing and training activities as part of the
relatively short-term settlement agreement therefore did not mean that
those restrictions were supported by the best available science, likely
to reduce impacts on marine mammals species or stocks and their
habitat, or practicable to implement from a military readiness
standpoint over the longer term in the HSTT Study Area. Accordingly, as
required by statute, NMFS analyzed the Navy's activities as set forth
in its application and including impacts, proposed mitigation, and
additional potential mitigation (including the settlement agreement
measures) pursuant to the ``least practicable adverse impact'' standard
to determine the appropriate mitigation to include in these
regulations. Some of the measures that were included in the 2015
settlement agreement are included in the final rule, while some are
not.
As characterized elsewhere in the rule, we look here at the
differences in both procedural mitigation measures and mitigation
areas. The 2015 settlement agreement included two procedural
mitigations (one of which was a group of related reporting measures).
Regarding one of the measures, the 2015 settlement agreement indicated
that ``Navy surface vessels operating within the HSTT shall avoid
approaching marine mammals head-on and shall maneuver to maintain a 500
yard (457 meter) mitigation zone for observed whales and a 200 yard
(183 meter) mitigation zone for all other observed marine mammals
(except bow riding dolphins), providing it is safe to do so.'' This
measure is fully included in this final rule. Regarding the other
measure, the settlement agreement included several related reporting
requirements for NMFS to implement in the event the discovery of an
injured or dead marine mammal triggered certain Navy reporting
requirements included in the 2013 rule. These reporting requirements
are not included in this rule both because it is not the role of
101(a)(5)(A) regulations to require reporting and notifications by NMFS
to others (where appropriate notice and opportunity for public
involvement is already provided for under the statute) and this
reporting by NMFS did not further the conservation of marine mammals.
Last, these settlement agreement reporting measures highlighted
inconsistencies between some of the measures required under the 2013
regulations and those inconsistencies have been resolved; the 2018 LOAs
include updated reporting requirements.
NMFS' and the Navy's analysis of mitigation areas is described in
the subsections above and the description of areas included in the
final rule are described in the subsection below. In order to assist
the reader in understanding the differences in mitigation areas between
the terms of the 2015 settlement agreement (as a result of the ruling
in Conservation Council for Hawaii v. National Marine Fisheries
Service, 97 F. Supp.3d 1210 (D. Haw. 2015)) and this final rule, we
offer the following:
Figures 1, 2, 3, and 4 below depict the settlement
mitigation areas and the HSTT Mitigation Areas for Hawaii and SOCAL.
Table 44 below compares the mitigation requirements
from the 2015 settlement agreement areas to the mitigation
requirements for the areas specified in this final rule (noting also
the species for which impacts will be reduced).
Table K.2-2 of Appendix K in the HSTT FEIS/OEIS
includes a comparison of the settlement agreement areas to
mitigation areas for this rulemaking period by species and BIAs.
NMFS' CetSound website includes an interactive map
depicting the BIAs for all species and stocks (there are 12
overlapping BIAs in the main Hawaiian Islands, making it difficult
to present them effectively in a static map). See https://cetsound.noaa.gov/biologically-important-area-map.
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Table 44--Comparison of Mitigation Areas in Effect 2015-2018 Under the
2015 Settlement Agreement to Mitigation Areas Implemented Under 2018
Final Rule
------------------------------------------------------------------------
Litigation settlement (2015-December HSTT final MMPA incidental take
2018) rule (December 2018-2023)
------------------------------------------------------------------------
Hawaii Hawaii
Area 1-A Hawaii Island Hawaii Island Mitigation
(North, South, East) (year- Area (year-round). Incorporates
round). (a) Prohibit the use of parts of settlement measures 1-A
MFAS for training and testing through 1-E and 2-A through 2-E.
activities during both MTEs and Navy will minimize the use of
unit-level training; and (b) MFAS (MF1 and MF4) and will not
prohibit the use of in-water use explosives during testing
explosives for training and and training. Reduces impacts on
testing activities. Reduces ESA-listed false killer whales
impacts to false killer whales, and monk seals, two species of
pygmy killer whales, short- beaked whales, humpback whales,
finned pilot whales, bottlenose and other species.
dolphins, spinner dolphins,
Cuvier's beaked whales, and
Blainville's beaked whales
Area 1-B Hawaii Island 4-Islands Region
(Northwest) (year-round). Limit Mitigation Area (November 1-
the use of MFAS for training and April 15 for active sonar, year-
testing activities during MTEs round for explosives).
to one Rim of the Pacific in Incorporates parts of settlement
2016, one Rim of the Pacific in Areas 1-A, 1-B, 1-C, 1-D, 1-E, 2-
2018, three Undersea Warfare A, 2-B, and 2-C and humpback
Exercises per calendar year, and reporting area. Navy will not
one Independent Deployer use MFAS (MF1) or explosives in
Certification Exercise per this mitigation area during
calendar year. Reduces impacts training and testing. Reduces
to humpback whales, false killer impacts to humpback whales, ESA-
whales, short-finned pilot listed false killer whales and
whales, melon-headed whales, monk seals, and some dolphin
bottlenose dolphins, spinner species.
dolphins, Cuvier's beaked Humpback Whale Special
whales, and Blainville's beaked Reporting Areas (December 15-
whales April 15). Incorporates parts of
settlement areas 1-B, 1-C, 1-D,
2-A, 2-B, and 2-D, humpback
special reporting area and
humpback cautionary area. Navy
will report the hours of MF1
used in these areas in training
and testing activity reports.
Humpback Whale Awareness
Notification Message Area
(November-April). Navy will
issue a seasonal awareness
notification message to alert
ships and aircraft operating in
the area to the possible
presence of concentrations of
large whales, including humpback
whales.
Area 1-C Hawaii Island .................................
(West) (year-round). (a) Limit
the use of MFAS for training and
testing activities during MTEs
to one Rim of the Pacific in
2016, one Rim of the Pacific in
2018, three Undersea Warfare
Exercises per calendar year, and
one Independent Deployer
Certification Exercise per
calendar year; (b) prohibit the
use of MFAS for training and
testing activities during unit-
level training (excluding unit-
level training conducted by
participants in an ongoing MTE;
and (c) prohibit the use of in-
water explosives for training
and testing activities. Reduces
impacts to humpback whales,
false killer whales, dwarf sperm
whales, pygmy killer whales,
short-finned pilot whales,
bottlenose dolphins, spotted
dolphins, spinner dolphins,
rough toothed dolphins, Cuvier's
beaked whales, and Blainville's
beaked whales
Area 1-D Hawaii Island .................................
(Southwest) (year-round). (a)
Limit the use of MFAS for
training and testing activities
during MTEs to one Rim of the
Pacific in 2016, one Rim of the
Pacific in 2018, three Undersea
Warfare Exercises per calendar
year, one Independent Deployer
Certification Exercise per
calendar year, and one
Sustainment Exercise per
calendar year; (b) prohibit the
use of MFAS for training and
testing activities during unit-
level training (excluding unit-
level training conducted by
participants in ongoing MTEs );
and (c) prohibit the use of in-
water explosives for training
and testing activities. Reduces
impacts to dwarf sperm whales,
pygmy killer whales, short-
finned pilot whales, bottlenose
dolphins, spotted dolphins,
spinner dolphins, rough-toothed
dolphins, Cuvier's beaked
whales, and Blainville's beaked
whales
Area 1-E and 2-E Hawaii .................................
Island (nearshore Northwest)
(year-round). Require that all
surface vessels use extreme
caution and proceed at safe
speed so they can take proper
and effective action to avoid a
collision with any sighted
object or disturbance, and can
be stopped within a distance
appropriate to the prevailing
circumstances and conditions.
Reduces impacts to dwarf sperm
whales, false killer whales,
pygmy killer whales, melon-
headed whales, bottlenose
dolphins, spotted dolphins,
spinner dolphins, rough-toothed
dolphins, and Blainville's
beaked whales
[[Page 66956]]
Area 2-A (Southeast .................................
Oahu, Southwest Molokai, Penguin
Bank) (year-round). (a) Prohibit
the use of MFAS for training and
testing activities during MTEs;
(b) prohibit the use of in-water
explosives for training and
testing activities; and (c)
require that all surface vessels
use extreme caution and proceed
at safe speed so they can take
proper and effective action to
avoid a collision with any
sighted object or disturbance,
and can be stopped within a
distance appropriate to the
prevailing circumstances and
conditions. Reduces impacts to
humpback whales, false killer
whales, bottlenose dolphins, and
spinner dolphins
Area 2-B (South Molokai, .................................
East Maui, Penguin Bank) (year-
round). (a) Prohibit the use of
in-water explosives for training
and testing activities; and (b)
require that all surface vessels
use extreme caution and proceed
at safe speed so they can take
proper and effective action to
avoid a collision with any
sighted object or disturbance,
and can be stopped within a
distance appropriate to the
prevailing circumstances and
conditions. Reduces impacts to
humpback whales, bottlenose
dolphins, spotted dolphins, and
spinner dolphins
Area 2-C (North Molokai, .................................
North Maui) (year-round). (a)
Prohibit the use of MFAS for
training and testing activities
during MTEs; (b) implement a
Protective Measure Assessment
Protocol measure advising
Commanding Officers that the
area is false killer whale
habitat and that they should
avoid using MFAS during unit-
level training within the area
whenever practicable; and (c)
prohibit the use of in-water
explosives for training and
testing activities (within the
overlap of Area 2-B and Area 2-
C, the restrictions imposed in
Area 2-B and Area 2-C both
apply). Reduces impacts to false
killer whales, bottlenose
dolphins, and spinner dolphins
Area 2-D (Southeast .................................
Oahu, Northwest Molokai) (year-
round). Prohibit the use of in-
water explosives for training
and testing activities. Reduces
impacts to false killer whales,
bottlenose dolphins, and spinner
dolphins
------------------------------------------------------------------------
Southern California Southern California
Area 3-A (San Diego Arc, San Diego Arc, San
coastal) (June 1-October 31). Nicolas Island, and Santa Monica/
(a) Prohibit the use of MFAS for Long Beach Mitigation Areas
training and testing activities (June 1-October 31).
during MTEs and unit-level Incorporates parts of settlement
training; and (b) require that areas 3-A, 3-B, 3-C, 4-A, 4-B, 4-
all surface vessels use extreme C, and 4-D. Navy will minimize
caution and proceed at safe the use of MFAS (MF1) within the
speed so they can take proper three Mitigation Areas during
and effective action to avoid a training and testing. Within the
collision with any sighted San Diego Arc Mitigation Area,
object or disturbance, and can Navy will not use explosives
be stopped within a distance during large-caliber gunnery,
appropriate to the prevailing torpedo, bombing, and missile
circumstances and conditions. activities during testing and
Reduces impacts to blue and gray training. Within the San Nicolas
whales Island Mitigation Area Navy will
not use explosives during mine
warfare, large-caliber gunnery,
torpedo, bombing and missile
activities during training.
Within the Santa Monica/Long
Beach Mitigation Area, Navy will
not use explosives during mine
warfare, large-caliber gunnery,
torpedo, bombing, and missile
(including 2.75'' rockets)
activities during training and
testing. Reduces impacts
primarily to blue whales, but
also gray and fin whales.
Santa Barbara Island
Mitigation Area (year-round).
Incorporates parts of settlement
areas 4A, Channel Island NMS.
Navy will not use MFAS (MF1) and
explosives in small-, medium-,
and large-caliber gunnery,
torpedo, bombing, and missile
activities during unit-level
training or MTEs. Reduces
impacts to numerous marine
mammal species that use the
Channel Islands NMS and
partially overlap areas for blue
whales and gray whales.
Blue Whale (June-
October), Gray Whale (November-
March), and Fin Whale (November-
May) Awareness Notification
Message Areas. Navy will issue a
seasonal awareness notification
message to alert ships and
aircraft operating in the area
to the possible presence of
concentrations of large whales,
particularly blue, gray, and fin
whales.
[[Page 66957]]
Area 3-B (San Diego Arc, .................................
coastal) (June 1-October 31).
(a) Prohibit the use of MFAS for
training and testing activities
during MTEs and unit-level
training, except for system
checks; (b) implement a seasonal
Protective Measure Assessment
Protocol measure advising
Commanding Officers that the
area is blue whale habitat and
that they should avoid
conducting system checks within
the area whenever practicable;
and (c) require that all surface
vessels use extreme caution and
proceed at safe speed so they
can take proper and effective
action to avoid a collision with
any sighted object or
disturbance, and can be stopped
within a distance appropriate to
the prevailing circumstances and
conditions. Reduces impacts to
blue and gray whales
Area 3-C (Santa Monica .................................
Bay to Long Beach, coastal)
(November 1-May 20). Require
that all surface vessels use
extreme caution and proceed at
safe speed so they can take
proper and effective action to
avoid a collision with any
sighted object or disturbance,
and can be stopped within a
distance appropriate to the
prevailing circumstances and
conditions. Reduces impacts to
blue and gray whales
Area 4-A (East of San .................................
Nicholas Island) (year-round).
(a) Prohibit the use of MFAS for
training and testing activities
during MTEs and unit-level
training; and (b) prohibit the
use of in-water explosives for
training and testing activities.
Reduces impacts to blue and gray
whales
Area 4-B (east of Santa .................................
Catalina Island) (year-round).
Prohibit the use of MFAS for
training and testing activities
during MTEs and unit-level
training. Reduces impacts to
gray whales
Area 4-C (Tanner-Cortes .................................
Bank) (June 1-October 31).
Require that all surface vessels
use extreme caution and proceed
at safe speed so they can take
proper and effective action to
avoid a collision with any
sighted object or disturbance,
and can be stopped within a
distance appropriate to the
prevailing circumstances and
conditions. Reduces impacts to
blue and gray whales
Area 4-D (south of 4-A) .................................
(year-round). Require all
surface vessels to use extreme
caution and proceed at a safe
speed so they can take proper
and effective action to avoid a
collision with any sighted
object or disturbance, and can
be stopped within a distance
appropriate to the prevailing
circumstances and conditions.
Reduces impacts to gray whales
------------------------------------------------------------------------
As described above, NMFS analyzed the Navy's activities as set
forth in its application, the impacts of those activities, the
proposed mitigation, and potential additional mitigation (including
the 2015 settlement agreement measures) pursuant to the ``least
practicable adverse impact'' standard to determine the appropriate
mitigation to include in these regulations. Some of the measures
that were included in the 2015 settlement agreement are included in
this final rule (for example, the vast majority of the area in
Hawaii included in the mitigation for the settlement agreement is
included in Mitigation Areas in this rule), while some are not (for
example, because of the instrumented ranges and specific training
needs in SOCAL, less of the area covered in the settlement agreement
is included as Mitigation Areas in this rule). As noted previously,
Appendix K (Geographic Mitigation Assessment) of the HSTT FEIS/OEIS
includes a detailed analysis of all of the potential mitigation
areas and associated measures (including the settlement measures
addressed in this section), in the context of both reduction of
marine mammal impacts and practicability. NMFS has independently
reviewed Appendix K (Geographic Mitigation Assessment), determined
that the analysis reflects the best available science, and used the
information to support our findings outlined in this Mitigation
Measures section. A summary of the rationale for not adopting the
relatively small subset of remaining 2015 settlement agreement
measures that were not carried forward follows.
In Hawaii, about 85 percent of the area that was covered by 2015
settlement areas is covered by mitigation areas in this final rule
(see Figures 1 and 2 above). The protected area around the island of
Hawaii is the same in this rule as it was in the 2015 settlement
agreement (Hawaii Mitigation Area), with the difference being that
the settlement agreement included mitigation on Penguin Bank and in
a couple of areas north of Molokai and Maui that are not included in
the 4-Islands Mitigation Area in this final rule. As explained in
more detail in the full analysis in Section 3 of Appendix K of the
HSTT FEIS/OEIS, Penguin Bank offers critical shallow and constrained
conditions for Navy training (especially submarines) that are not
available anywhere else in Hawaii. The areas north of Molokai and
Maui that are not included in the current 4-Islands Mitigation Area
are similarly critical for certain exercises that specifically
include torpedo exercises deliberately conducted in this area north
of the islands to avoid the other suitable training areas between
the four islands where humpback whale density is higher. The 2015
settlement agreement mitigation restricted all MFAS and explosive
use on Penguin Bank (area 2-A), however, as the Navy explains, this
MFAS restriction is impracticable in that it would have unacceptable
impacts on their training and testing capabilities. In addition, the
Navy does not typically use explosives in this area. For the
settlement areas north of Molokai and Maui that are not covered in
the rule (area 2-B and part of area 2-C), the settlement agreement
restricted explosive use but did not restrict MFAS in the 2-B area.
Explosive use in these areas is also already rare, but for the
reasons described in Appendix K,
[[Page 66958]]
restricting MFAS use is impracticable and would have unacceptable
impacts on training and testing. We also note that while it is not
practicable to restrict MFAS use on Penguin Bank, MFAS use is
relatively low and we have identified it as a special reporting area
for which the Navy will report the MFAS use in that area to inform
adaptive management discussions in the future. Additionally, some of
the areas that the 2015 settlement agreement identified included
language regarding extra vigilance intended to avoid vessel strikes.
Neither NMFS nor the Navy thought that inclusion of this term as
written would necessarily reduce the probability of a vessel strike,
so instead we have included the Humpback Whale Awareness
Notification provision, which sends out a message to all Navy
vessels in Hawaii during the time that humpback whales are present.
Last we note that the 2015 settlement mitigation areas with MFAS
restrictions sometimes excluded all MFAS, while sometimes they
limited the number of MTEs that could occur (with no limit on any
particular type of sonar, meaning that hull-mounted surface ship
sonar could be operated), whereas the sonar restrictions in this
final rule limit the use of surface ship hull-mounted sonar, which
is the source that results in the vast majority of incidental takes.
For SOCAL, the 2015 settlement areas had four primary
objectives: Reducing impacts in blue whale feeding areas, reducing
the likelihood of large whale vessel strikes, minimizing incidental
take of gray whales, and minimizing incidental take of beaked whales
in areas that the plaintiffs argued were specifically important to
beaked whales. As noted previously, of the four blue whale feeding
areas in SOCAL, the Navy mitigation areas in this rule fully cover
three of them (those associated with settlement areas 3-A, 3-B, 4-A,
and 4-B in the 2015 settlement agreement) and limit surface ship
hull-mounted MFAS and explosive use. In fact, we included
protections for the southern end of a blue whale feeding BIA (Santa
Monica/Long Beach area), by limiting hull-mounted MFAS and
explosives that were not included in the 2015 settlement areas. The
fourth blue whale feeding BIA, Tanner-Cortes Banks, provides unique
and irreplaceable shallow-water conditions that are critical for
shallow-water training and testing (especially for submarines) and
that are not available elsewhere in SOCAL, along with a shallow-
water minefield training range. Notably, in a satellite tracking
study of blue whales in Southern California from 2014 to 2017,
Tanner-Cortes Banks was only transited minimally by individual blue
whales (Mate et al., 2018). Limiting activities in this area would
inhibit the Navy's ability to successfully test and train and is
impracticable. In fact, the 2015 settlement area at Tanner-Cortes
Banks did not limit MFAS or explosive use. Rather, Tanner-Cortes
Banks (area 4-C), settlement area 4-D, and the large settlement area
close to shore (area 3-C) each only had one associated protective
measure, which was language regarding extra vigilance intended to
avoid vessel strikes. However, neither NMFS nor the Navy thought
that inclusion of this term as written would necessarily reduce the
probability of a vessel strike, so instead we have included the Blue
Whale, Gray Whale, and Fin Whale Awareness Notification Area, which
sends out a message to all Navy vessels in SOCAL during the time
these large whales are present and will more effectively help to
reduce the probability of ship strike.
The remaining areas covered by 2015 settlement mitigation areas
that are not covered by mitigation areas in this final rule (area 4-
B and the outer edges of area 4-A, which does not align exactly with
the blue whale BIA like the current Navy mitigation area does) were
intended to reduce impacts on gray whales and to provide some sort
of protection for beaked whales. However, NMFS and the Navy disagree
that the remaining 2015 settlement areas provide the protection the
plaintiffs assert. As noted earlier, gray whales migrate primarily
through a 5 to 10 km corridor along the West Coast, with some
individuals occasionally ranging offshore (noting that mother/calf
pairs always stay very close to shore), which resulted in the BIA
recognizing a 47-km buffer beyond the 5 to 10 km main migration
corridor, but also expanding the BIA further offshore in order to
encompass the Channel Islands, where some individuals also sometimes
range further. Prohibiting activities outside of the main migration
corridor in an area where gray whales may be present only
occasionally is not expected to meaningfully reduce effects,
especially if the mitigation area is small compared to the much
larger buffer area and the same amount of activities occur outside
of the mitigation area, but still in the larger area that gray
whales occupy. Regarding beaked whales, the plaintiffs in the
Conservation Council for Hawaii case indicated that settlement area
4-B would provide important habitat for beaked whales based on
tagging data from two whales in 2014. However, while beaked whales
are present in the area, tagging data through 2018 (for 27 Cuvier's
beaked whales) shows that these whales have site fidelity to the
SOAR Range and typically do not move toward the 2015 settlement
areas when they do leave SOAR. In other words, since the 2015
settlement area is not an area of known particular importance for
these whales, protecting it would not be expected to reduce impacts.
Appendix K of the HSTT FEIS/OEIS explains in detail why additional
limitations in this area would inhibit training and testing and
thereby be impracticable, and the Comments and Responses section of
this rule addresses these recommendations specifically. In summary,
the mitigation areas identified in this rule address the valid
concerns that were targeted through the 2015 settlement agreement,
but areas that were either impracticable to continue to implement or
do not provide a reduction in impacts on marine mammals were not
carried forward.
The final Procedural Mitigation measures and Mitigation Area
measures are described in the sections below.
Final Procedural Mitigation
Procedural mitigation is mitigation that the Navy will implement
whenever and wherever an applicable training or testing activity
takes place within the HSTT Study Area. The Navy customizes
procedural mitigation 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 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 45) is designed to aid Lookouts and
other applicable personnel with their observation, environmental
compliance, and reporting responsibilities. The remainder of the
procedural mitigation measures (Tables 45 through Tables 64) are
organized by stressor type and activity category and includes
acoustic stressors (i.e., active sonar, air guns, pile driving,
weapons firing noise), explosive stressors (i.e., sonobuoys,
torpedoes, medium-caliber and large-caliber projectiles, missiles
and rockets, bombs, sinking exercises, mines, underwater demolition
multiple charge mat weave and obstacles loading, anti-swimmer
grenades), 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 and
rockets, non-explosive bombs and mine shapes).
Table 45-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 specific activities must 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:
[[Page 66959]]
--Introduction to the U.S. Navy Afloat Environmental Compliance
Training Series. The introductory module provides information
on environmental laws (e.g., ESA, MMPA) 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.
------------------------------------------------------------------------
Procedural Mitigation for Acoustic Stressors
Mitigation measures for acoustic stressors are provided in
Tables 46 through 49.
Procedural Mitigation for Active Sonar
Procedural mitigation for active sonar is described in Table 46
below.
Table 46--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 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 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:
--During the activity, at 1,000 yd Navy personnel must power
down 6 dB, at 500 yd, Navy personnel must power down an
additional 4 dB (for a total of 10 dB), and at 200 yd Navy
personnel must shut down for low-frequency active sonar >=200
decibels (dB) and hull-mounted mid-frequency active sonar.
--200 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.
Prior to the initial start of the activity (e.g., when
maneuvering on station):
--Observe the mitigation zone for floating vegetation; if
floating vegetation is observed, relocate or delay the start
until the mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine
mammals are observed, relocate or delay the start of active
sonar transmission.
During the activity:
--Low-frequency active sonar >=200 decibels (dB) and hull-
mounted mid-frequency active sonar: Navy personnel must observe
the mitigation zone for marine mammals; power down active sonar
transmission by 6 dB if marine mammals are observed within
1,000 yd of the sonar source; power down an additional 4 dB
(for a total of 10 dB total) within 500 yd; cease transmission
within 200 yd.
--Low-frequency active sonar <200 dB, mid-frequency active sonar
sources that are not hull-mounted, and high-frequency active
sonar: Observe the mitigation zone for marine mammals; cease
active sonar transmission if marine mammals are observed within
200 yd of the sonar source.
Commencement/recommencement conditions after a marine
mammal sighting before or during the 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) 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 min. for aircraft-deployed sonar sources or 30
min. 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 ship 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).
------------------------------------------------------------------------
[[Page 66960]]
Procedural Mitigation for Air Guns
Procedural mitigation for air guns is described in Table 47
below.
Table 47--Procedural Mitigation for Air Guns
------------------------------------------------------------------------
Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
Air guns.
Number of Lookouts and Observation Platform:
1 Lookout must be positioned on a ship or pierside.
Mitigation Requirements:
Mitigation zone:
--150 yd around the air gun
Prior to the initial start of the activity (e.g., when
maneuvering on station):
--Observe the mitigation zone for floating vegetation; if
floating vegetation is observed, relocate or delay the start
until the mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine
mammals are observed, relocate or delay the start of air gun
use.
During the activity:
--Observe the mitigation zone for marine mammals; if marine
mammals are observed, cease air gun use.
Commencement/recommencement conditions after a marine
mammal sighting before or during the 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
air gun use) 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 air gun; (3) the mitigation zone has been clear
from any additional sightings for 30 min.; or (4) for mobile
activities, the air gun has transited a distance equal to
double that of the mitigation zone size beyond the location of
the last sighting.
------------------------------------------------------------------------
Procedural Mitigation for Pile Driving
Procedural mitigation for pile driving is described in Table 48
below.
Table 48--Procedural Mitigation for Pile Driving
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Pile driving and pile extraction sound during Elevated
Causeway System training.
Number of Lookouts and Observation Platform:
1 Lookout must be positioned on the shore, the elevated
causeway, or a small boat.
Mitigation Requirements:
Mitigation zone:
--100 yd around the pile.
Prior to the initial start of the activity (for 30 min.):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, delay the start until the mitigation zone
is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, delay the start of pile driving or vibratory pile
extraction.
During the activity:
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease impact pile driving or vibratory pile
extraction.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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
pile driving or pile extraction) 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 pile driving location; or (3) the
mitigation zone has been clear from any additional sightings for 30
min.
------------------------------------------------------------------------
Procedural Mitigation for Weapons Firing Noise
Procedural mitigation for weapons firing noise is described in
Table 49 below.
Table 49--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 must be positioned on the ship conducting the
firing.
[[Page 66961]]
--Depending on the activity, the Lookout could be the same one
provided for under Explosive Medium-Caliber and Large-Caliber
Projectiles or under Small-, Medium, and Large-Caliber Non-
Explosive Practice Munitions.
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:
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start of weapons
firing until the mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, relocate or delay the start of weapons firing.
During the activity:
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease weapons firing.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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) 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 min.; 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.
------------------------------------------------------------------------
Procedural Mitigation for Explosive Stressors
Mitigation measures for explosive stressors are provided in
Tables 50 through 59.
Procedural Mitigation for Explosive Sonobuoys
Procedural mitigation for explosive sonobuoys is described in
Table 50 below.
Table 50--Procedural Mitigation for Explosive Sonobuoys
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Explosive sonobuoys.
Number of Lookouts and Observation Platform:
1 Lookout must be positioned must be positioned in an
aircraft or on small boat.
If additional platforms are participating in the activity,
personnel positioned in those assets (e.g., safety observers,
evaluators) must support observing the mitigation zone for
applicable biological resources 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 min.):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start until the
mitigation zone is clear.
--Conduct passive acoustic monitoring for marine mammals; use
information from detections to assist visual observations.
--Visually observe the mitigation zone for marine mammals; if marine
mammals are observed, relocate or delay the start of sonobuoy or
source/receiver pair detonations.
During the activity:
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease sonobuoy or source/receiver pair detonations.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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) 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.
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), observe
the vicinity of where detonations occurred; if any injured or dead
marine mammals are observed, follow established incident reporting
procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
Procedural Mitigation for Explosive Torpedoes
Procedural mitigation for explosive torpedoes is described in
Table 51 below.
[[Page 66962]]
Table 51--Procedural Mitigation for Explosive Torpedoes
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Explosive torpedoes.
Number of Lookouts and Observation Platform:
1 Lookout must be positioned in an aircraft.
If additional platforms are participating in the activity,
personnel positioned in those assets (e.g., safety observers,
evaluators) must support observing the mitigation zone for
applicable biological resources 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):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start until the
mitigation zone is clear.
--Conduct passive acoustic monitoring for marine mammals; use
information from detections to assist visual observations.
--Visually observe the mitigation zone for marine mammals and
jellyfish aggregations; if marine mammals or jellyfish aggregations
are observed, relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals and jellyfish
aggregations; if marine mammals and jellyfish aggregations are
observed, cease firing.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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) 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 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 (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), observe
the vicinity of where detonations occurred; if any injured or dead
marine mammals are observed, follow established incident reporting
procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
Procedural Mitigation for Medium- and Large-Caliber Projectiles
Procedural mitigation for medium- and large-caliber projectiles
is described in Table 52 below.
Table 52--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 must be on the vessel or aircraft 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.
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 while performing their regular
duties.
Mitigation Requirements:
Mitigation zones:
--200 yd around the intended impact location for air-to-surface
activities using explosive medium-caliber projectiles.
--600 yd around the intended impact location for surface-to-surface
activities using explosive medium-caliber projectiles.
--1,000 yd around the intended impact location for surface-to-
surface activities using explosive large-caliber projectiles.
Prior to the initial start of the activity (e.g., when
maneuvering on station):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start until the
mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease firing.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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) 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 min. for aircraft-based firing or 30
min. 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):
[[Page 66963]]
--When practical (e.g., when platforms are not constrained by fuel
restrictions or mission-essential follow-on commitments), observe
the vicinity of where detonations occurred; if any injured or dead
marine mammals are observed, follow established incident reporting
procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
Procedural Mitigation for Explosive Missiles and Rockets
Procedural mitigation for explosive missiles and rockets is
described in Table 53 below.
Table 53--Procedural Mitigation for Explosive Missiles and Rockets
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Aircraft-deployed explosive missiles and rockets.
--Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform:
1 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 while performing their regular
duties.
Mitigation Requirements:
Mitigation zones:
--900 yd around the intended impact location for missiles or rockets
with 0.6-20 lb. net explosive weight.
--2,000 yd around the intended impact location for missiles with 21-
500 lb. net explosive weight.
Prior to the initial start of the activity (e.g., during a fly-
over of the mitigation zone):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start until the
mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease firing.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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) 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 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 (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), observe
for marine mammals in the vicinity of where detonations occurred;
if any injured or dead marine mammals are observed, follow
established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
Procedural Mitigation for Explosive Bombs
Procedural mitigation for explosive bombs is described in Table
54 below.
Table 54--Procedural Mitigation for Explosive Bombs
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Explosive bombs.
Number of Lookouts and Observation Platform:
1 Lookout must be positioned in the 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 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):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start of bomb
deployment until the mitigation zone is clear.
[[Page 66964]]
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, relocate or delay the start of bomb deployment.
During the activity (e.g., during target approach):
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease bomb deployment.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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) 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), observe
for marine mammals in the vicinity of where detonations occurred;
if any injured or dead marine mammals are observed, follow
established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
Procedural Mitigation for Sinking Exercises
Procedural mitigation for sinking exercises is described in
Table 55 below.
Table 55--Procedural Mitigation for Sinking Exercises
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Sinking exercises.
Number of Lookouts and Observation Platform:
2 Lookouts (one must be positioned in an aircraft and one
must be on a vessel).
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 while performing their regular
duties.
Mitigation Requirements:
Mitigation zone:
--2.5 nmi around the target ship hulk.
Prior to the initial start of the activity (90 min. prior to
the first firing):
--Conduct aerial observations of the mitigation zone for floating
vegetation; delay the start of firing until the mitigation zone is
clear.
--Conduct aerial observations of the mitigation zone for marine
mammals and jellyfish aggregations; if marine mammals or jellyfish
aggregations are observed, delay the start of firing.
During the activity:
--Conduct passive acoustic monitoring for marine mammals; use
information from detections to assist visual observations.
--Visually observe the mitigation zone for marine mammals from the
vessel; if marine mammals are observed, Navy personnel must cease
firing.
--Immediately after any planned or unplanned breaks in weapons
firing of longer than 2 hours, observe the mitigation zone for
marine mammals from the aircraft and vessel; if marine mammals are
observed, Navy personnel must delay recommencement of firing.
Commencement/recommencement conditions after a marine mammal
sighting before or during the activity:
--The Navy 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) 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 target ship
hulk; or (3) the mitigation zone has been clear from any additional
sightings for 30 min.
After completion of the activity (for 2 hours after sinking the
vessel or until sunset, whichever comes first):
--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), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
Procedural Mitigation for Explosive Mine Countermeasure and
Neutralization Activities
Procedural mitigation for explosive mine countermeasure and
neutralization activities is described in Table 56 below.
Table 56--Procedural Mitigation for Explosive Mine Countermeasure and
Neutralization Activities
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
[[Page 66965]]
Explosive mine countermeasure and neutralization
activities.
Number of Lookouts and Observation Platform:
1 Lookout must be positioned on a vessel or in an aircraft
when implementing the smaller mitigation zone.
2 Lookouts (one must be positioned in an aircraft and one
must be 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 while performing their regular
duties.
Mitigation Requirements:
Mitigation zones:
--600 yd around the detonation site for activities using 0.1-5-lb
net explosive weight.
--2,100 yd around the detonation site for activities using 6-650 lb
net explosive weight (including high explosive target mines).
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):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start of detonations
until the mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, relocate or delay the start of detonations.
During the activity:
--Observe the mitigation zone for marine mammals, concentrations of
seabirds, and individual foraging seabirds; if for marine mammals,
concentrations of seabirds, and individual foraging seabirds are
observed, cease detonations.
Commencement/recommencement conditions after a marine mammal
sighting before or during the activity or a sighting of seabird
concentrations or individual foraging seabirds during the 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) 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):
--Observe for marine mammals in the vicinity of where detonations
occurred; if any injured or dead marine mammals are observed,
follow established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
Procedural Mitigation for Explosive Mine Neutralization Activities
Involving Navy Divers
Procedural mitigation for explosive mine neutralization
activities involving Navy divers is described in Table 57 below.
Table 57--Procedural Mitigation for Explosive Mine Neutralization
Activities Involving Navy Divers
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Explosive mine neutralization activities involving Navy
divers.
Number of Lookouts and Observation Platform:
2 Lookouts (two small boats with one Lookout each, or one
Lookout must be on a small boat and one must be in a rotary-wing
aircraft) when implementing the smaller mitigation zone.
4 Lookouts (two small boats with two Lookouts each), and a
pilot or member of an aircrew must serve as an additional Lookout
if aircraft are used during the activity, when implementing the
larger mitigation zone.
All divers placing the charges on mines must support the
Lookouts while performing their regular duties and must report
applicable sightings to their supporting small boat or Range Safety
Officer.
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 while performing their regular
duties.
Mitigation Requirements:
Mitigation zones:
--500 yd around the detonation site during activities under positive
control using 0.1-20 lb net explosive weight.
--1,000 yd around the detonation site during activities using time-
delay fuses (0.1-29 lb net explosive weight) and during activities
under positive control using 21-60 lb net explosive weight charges.
Prior to the initial start of the activity (e.g., when
maneuvering on station for activities under positive control; 30 min.
for activities using time-delay firing devices):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start of detonations
or fuse initiation until the mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, relocate or delay the start of detonations or fuse
initiation.
During the activity:
[[Page 66966]]
--Observe the mitigation zone for marine mammals, concentrations of
seabirds, and individual foraging seabirds (in the water and not on
shore); if marine mammals, concentrations of seabirds, and
individual foraging seabirds are observed, cease detonations or
fuse initiation.
--To the maximum extent practicable depending on mission
requirements, safety, and environmental conditions, Navy must
position boats mustnear the mid-point 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
(when two boats are used), 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.
--If used, aircraft must travel in a circular pattern around the
detonation location to the maximum extent practicable.
--Navy personnel must not set time-delay firing devices (0.1-29 lb.
net explosive weight) to exceed 10 min.
--During activities conducted in shallow water, a shore-based
observer must survey the mitigation zone with binoculars for birds
before and after each detonation. If training involves multiple
detonations, the second (or third, etc.) detonation must occur
either immediately after the preceding detonation (i.e., within 10
seconds) or after 30 min. to avoid potential impacts on birds
foraging underwater.
Commencement/recommencement conditions after a marine mammal
sighting before or during the activity or a sighting of seabird
concentrations or individual foraging seabirds during the 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) 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 detonation site; or (3)
the mitigation zone has been clear from any additional sightings
for 10 min. during activities under positive control with aircraft
that have fuel constraints, or 30 min. during activities under
positive control with aircraft that are not typically fuel
constrained and during activities using time-delay firing devices.
After completion of an activity (for 30 min):
--Observe for marine mammals in the vicinity of where detonations
occurred; if any injured or dead marine mammals are observed,
follow established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
Procedural Mitigation for Underwater Demolition Multiple Charge--Mat
Weave and Obstacle Loading
Procedural mitigation for underwater demolition multiple
charge--mat weave and obstacle loading is described in Table 58
below.
Table 58--Procedural Mitigation for Underwater Demolition Multiple
Charge--Mat Weave and Obstacle Loading
------------------------------------------------------------------------
Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
Underwater Demolition Multiple Charge--Mat Weave and
Obstacle Loading exercises.
Number of Lookouts and Observation Platform:
2 Lookouts (one must be on a small boat and one must be on
shore from an elevated platform).
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 while performing their regular
duties.
Mitigation Requirements:
Mitigation zone:
--700 yd around the detonation location.
Prior to the initial start of the activity:
--For 30 min. prior to the first detonation, the Lookout positioned
on a small boat must observe the mitigation zone for floating
vegetation and marine mammals; if floating vegetation or marine
mammals are observed, delay the start of detonations.
--For 10 min. prior to the first detonation, the Lookout positioned
on shore must use binoculars to observe the mitigation zone for
marine mammals; if marine mammals are observed, delay the start of
detonations until the mitigation zone has been clear of any
additional sightings for a minimum of 10 min.
During the activity:
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease detonations.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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) 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 location; or (3) the mitigation zone has been clear from
any additional sightings for 10 min. (as determined by the shore
observer).
After completion of the activity (for 30 min.):
--The Lookout positioned on a small boat 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), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
[[Page 66967]]
Procedural Mitigation for Maritime Security Operations--Anti-Swimmer
Grenades
Procedural mitigation for maritime security operations--anti-
swimmer grenades is described in Table 59 below.
Table 59--Procedural Mitigation for Maritime Security Operations--Anti-
Swimmer Grenades
------------------------------------------------------------------------
Procedural Mitigation Description
-------------------------------------------------------------------------
Stressor or Activity:
Maritime Security Operations--Anti-Swimmer Grenades.
Number of Lookouts and Observation Platform:
1 Lookout must be positioned on the small boat 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 while performing their regular
duties.
Mitigation Requirements:
Mitigation zone:
--200 yd around the intended detonation location.
Prior to the initial start of the activity (e.g., when
maneuvering on station):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start of detonations
until the mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, relocate or delay the start of detonations.
During the activity:
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease detonations.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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) 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 detonation location; (3) the mitigation zone has been
clear from any additional sightings for 30 min.; or (4) the
intended detonation 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), observe
for marine mammals in the vicinity of where detonations occurred;
if any injured or dead marine mammals are observed, follow
established incident reporting procedures.
--If additional platforms are supporting this activity (e.g.,
providing range clearance), these assets must assist in the visual
observation of the area where detonations occurred.
------------------------------------------------------------------------
Procedural Mitigation for Physical Disturbance and Strike Stressors
Mitigation measures for physical disturbance and strike
stressors are provided in Table 60 through Table 64.
Procedural Mitigation for Vessel Movement
Procedural mitigation for vessel movement is described in Table
60 below.
Table 60--Procedural Mitigation for Vessel Movement
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Vessel movement:
--The mitigation must 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), (3) the vessel is operated
autonomously, or (4) when impractical based on mission requirements
(e.g., during Amphibious Assault--Battalion Landing exercises).
Number of Lookouts and Observation Platform:
1 Lookout must be on the vessel that is underway.
Mitigation Requirements:
Mitigation zones:
--500 yd around whales.
--200 yd around other marine mammals (except bow-riding dolphins and
pinnipeds hauled out on man-made navigational structures, port
structures, and vessels).
During the activity:
--When underway, observe the mitigation zone for marine mammals; if
marine mammals are observed, Navy personnel must maneuver to
maintain distance.
Additional requirements:
--If a marine mammal vessel strike occurs, Navy personnel must
follow the established incident reporting procedures.
------------------------------------------------------------------------
[[Page 66968]]
Procedural Mitigation for Towed In-Water Devices
Procedural mitigation for towed in-water devices is described in
Table 61 below.
Table 61--Procedural Mitigation for Towed In-Water Devices
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Towed in-water devices:
--Mitigation applies to devices that are towed from a manned surface
platform or manned aircraft.
--The mitigation must not be applied if the safety of the towing
platform or in-water device is threatened.
Number of Lookouts and Observation Platform:
1 Lookout must be positioned on the manned towing platform.
Mitigation Requirements:
Mitigation zones:
--250 yd around marine mammals.
During the activity (i.e., when towing an in-water device):
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, Navy personnel must maneuver to maintain distance.
------------------------------------------------------------------------
Procedural Mitigation for Small-, Medium-, and Large-Caliber Non-
Explosive Practice Munitions
Procedural mitigation for small-, medium-, and large-caliber
non-explosive practice munitions is described in Table 62 below.
Table 62--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 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.
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):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start of firing until
the mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease firing.
Commencement/recommencement conditions after a marine mammal
sighting before or during the 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) 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 min. for aircraft-based firing or 30
min. 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.
------------------------------------------------------------------------
Procedural Mitigation for Non-Explosive Missiles and Rockets
Procedural mitigation for non-explosive missiles and rockets is
described in Table 63 below.
Table 63--Procedural Mitigation for Non-Explosive Missiles and Rockets
------------------------------------------------------------------------
Procedural mitigation description
-------------------------------------------------------------------------
Stressor or Activity:
Aircraft-deployed non-explosive missiles and rockets:
--Mitigation applies to activities using a surface target.
Number of Lookouts and Observation Platform:
1 Lookout must be positioned in an aircraft.
[[Page 66969]]
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):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start of firing until
the mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, relocate or delay the start of firing.
During the activity:
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, cease firing.
Commencement/recommencement conditions after a marine mammal
sighting prior to or during the 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) 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 min. when the activity involves
aircraft that have fuel constraints, or 30 min. when the activity
involves aircraft that are not typically fuel constrained.
------------------------------------------------------------------------
Procedural Mitigation for Non-Explosive Bombs and Mine Shapes
Procedural mitigation for non-explosive bombs and mine shapes is
described in Table 64 below.
Table 64--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 must be positioned in an aircraft.
Mitigation Requirements:
Mitigation zone:
--1,000 yd around the intended target.
Prior to the start of the activity (e.g., when arriving on
station):
--Observe the mitigation zone for floating vegetation; if floating
vegetation is observed, relocate or delay the start of bomb
deployment or mine laying until the mitigation zone is clear.
--Observe the mitigation zone for marine mammals; if marine mammals
are observed, 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):
--Observe the mitigation zone for marine mammals and; if marine
mammals are observed, cease bomb deployment or mine laying.
Commencement/recommencement conditions after a marine mammal
sighting prior to or during the 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) 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 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.
------------------------------------------------------------------------
Final 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 (see Figures 2 and 4 above and
the revised figures provided in the HSTT FEIS/OEIS for specific
information on the location and boundaries of each mitigation area).
A full technical analysis (for which the methods were summarized
above) of the mitigation areas that the Navy considered for marine
mammals is provided in Appendix K (Geographic Mitigation Assessment)
of the HSTT FEIS/OEIS. The Navy has taken into account public
comments received on the HSTT DEIS/OEIS, best available science, and
the practicability of implementing additional mitigation measures
and has enhanced its mitigation areas and mitigation measures to
further reduce impacts to marine mammals. The Navy has therefore
revised their mitigation areas since their application (changes
noted at the beginning of this section). The Navy re-analyzed
existing mitigation areas and considered new habitat areas suggested
by the public, NMFS, and other non-governmental organizations,
including main Hawaiian Islands insular false killer whale ESA
designated critical habitat, important habitat for large whales in
SOCAL, BIAs, and National Marine Sanctuaries. The Navy worked
collaboratively with NMFS to develop mitigation areas using inputs
from the Navy's operational community, the best available science
discussed in Chapter 3 of the HSTT FEIS/OEIS (Affected Environment
and Environmental Consequences section), published literature,
predicted activity impact footprints, marine species monitoring and
density data, and the practicability of implementing additional
mitigations.
NMFS conducted an independent analysis of the mitigation areas
that the Navy will implement and that are included in this rule,
which are described below. NMFS concurs with the Navy's analysis,
which indicates that the measures in these mitigation areas are both
practicable and will reduce the likelihood or severity of adverse
impacts to marine mammal species or stocks or their habitat in the
manner described in the Navy's analysis and this rule. We note that
NMFS is
[[Page 66970]]
heavily reliant on the Navy's assessment of practicability, since
the Navy is best equipped to judge 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. We further describe and
summarize the manner in which the Area Mitigations in the rule will
reduce the likelihood or severity of adverse impacts to marine
mammal species or stocks or their habitat below.
Mitigation Areas in Hawaii
Hawaii Island Mitigation Area: The Navy will not use more than
300 hours of MF1 surface hull-mounted MFAS (the source that results
in, by far, the highest numbers of take) or 20 hours of MF4 dipping
sonar in a year, or explosives across this large area at any time of
the year. This mitigation area overlaps the entirety of several
small, resident populations (BIAs) of odontocetes that occur only
around the island of Hawaii (Hawaii stocks of dwarf sperm whale,
pygmy killer whale, short-finned pilot whale, melon-headed whale,
bottlenose dolphin, and Blaineville's beaked whale) and about 80 and
90 percent, respectively, of the Hawaii stocks of the rough-toothed
dolphin and Cuvier's beaked whale. For small resident populations,
we aim to avoid overwhelming small populations (which are more
susceptible to certain adverse impacts on population rates of growth
and survival, such as Allee effects) with large scale impacts,
especially when the population is limited to a small area and less
able to access alternative habitat. By minimizing exposure to the
most impactful sonar sources and not using explosives, both the
magnitude and severity of both behavioral impacts and potential
hearing impairment are greatly reduced. There are also several small
resident populations (BIAs) of odontocetes that span multiple
islands, and this mitigation area overlaps all of the stock's range
around the island of Hawaii for false killer whales (Main Hawaiian
Island insular stock) and spinner dolphins (Hawaiian Islands stock),
and about 90 percent of the range around the island of Hawaii for
pantropical spotted dolphins (Hawaii stock). Additionally, critical
habitat has been designated, pursuant to the ESA, for false killer
whales (Main Hawaiian Island insular stock) in waters between 45 and
3,200 meters depth around all of the main Hawaiian islands, and this
mitigation area captures more than 95 percent of this area around
the island of Hawaii. Stocks that span multiple islands and have
larger total area within their range are generally considered
somewhat less vulnerable than those with smaller ranges, but
nonetheless, this mitigation area (along with the addition of the 4-
Islands Mitigation Area discussed immediately below) offers
significant reduction of impacts to these stocks.
This mitigation area also overlaps an important breeding and
calving area (BIA) for the Central North Pacific stock of humpback
whales (of note, the BIA entirely contains, and is slightly larger
than, the Hawaii Humpback Whale National Marine Sanctuary). This BIA
includes areas adjacent to all of the Main Hawaiian Islands, and
this mitigation area encompasses the important area adjacent to the
island of Hawaii. For humpback whales, the reduction of activities
and associated impacts (behavioral disturbance or TTS) in this area
for individuals that have calves or are potentially breeding is
expected to reduce the probability or severity of impacts that would
be more likely to adversely impact reproduction or survival of
individuals by directly interfering with breeding behaviors or by
separating mothers and calves at a time when calves are more
susceptible to predators and less able to care for and feed
themselves.
Critical habitat has been designated, pursuant to the ESA, for
the Hawaiian monk seal from the shore out to the 200-m depth line
(but only between the bottom and 10 meters above the bottom) in
multiple areas on 10 islands of the Northwestern Hawaiian Islands
and six islands of the Main Hawaiian Islands. These areas include:
(1) Significant coastal areas where seals haul out for resting,
molting, socializing, and avoiding predators; (2) preferred coastal
and marine nursery grounds where seals haul out for pupping and
nursing, and (3) marine areas where seals hunt and feed. This
mitigation area overlaps all of their critical habitat around the
Island of Hawaii and, by not using explosives or the most impactful
sonar sources in this area, thereby reduces the likelihood that take
might impact reproduction or survival by interfering with important
feeding or resting behaviors (potentially having adverse impacts on
energy budgets) or separating mothers and pups in times when pups
are more susceptible to predation and less able to feed or otherwise
take care of themselves.
4-Islands Region Mitigation Area: The Navy will not use MF1
surface hull-mounted MFAS (the source that results in, by far, the
highest numbers of take) from November 15 through April 15 or use
explosives in this area at any time of the year. The Maui/Molokai
area (4-Islands Region) is an important reproductive and calving
area for humpback whales (another section of the BIA, and including
a greater area than the Hawaii island section), and the mitigation
area overlaps the entirety of this BIA between the islands of Maui,
Molokai, Lanai, and Kaho'alawe. As noted above, the reduction of
activities in this area with individuals that have calves or are
potentially breeding is expected to reduce the probability or
severity of impacts that would be more likely to adversely impact
reproduction or survival of individuals by directly interfering with
breeding behaviors or by separating mothers and calves at a time
when calves are more susceptible to predators and less able to care
for and feed themselves.
In addition, as noted above, there are also several small
resident populations of marine mammals (BIAs) that span multiple
islands, and this mitigation area overlaps about 80 percent of the
pantropical spotted dolphin (Hawaii stock) area adjacent to these
four islands (one of three discrete areas of the BIA), about 40
percent of the portion of the false killer whale's (Main Hawaiian
Island insular stock) range that spans an area north of Molokai and
Maui (one of the two significantly larger areas that comprise the
false killer whale BIA), and a good portion of the BIA for spinner
dolphins (Hawaiian Islands stock), which spans the Main Hawaiian
Islands in one large continuous area. As noted above, the critical
habitat for false killer whales extends fairly far out (to 3,200
meters depth) around all the Main Hawaiian Islands. As described in
the Hawaii Island Mitigation Area section above, by limiting
exposure to the most impactful sonar source and explosives for these
stocks, in this 4-Islands Region Mitigation Area in addition to the
Hawaii Island Mitigation Area both the magnitude and severity of
both behavioral impacts and potential hearing impairment are greatly
reduced.
Also as noted first above, critical habitat has been designated
for the Hawaiian monk seal from the shore out to the 200-m depth
line around the four islands targeted with this mitigation area. The
mitigation area overlaps more than half of the critical habitat
around these four islands and by not using explosives or the most
impactful sonar sources in this area, the likelihood that take might
impact reproduction or survival by interfering with important
feeding or resting behaviors (potentially having adverse impacts on
energy budgets) or separating mothers and pups in times when pups
are more susceptible to predation and less able to feed or otherwise
take care of themselves is greatly reduced.
Humpback Whale Awareness Notification Message Area: The Navy
will issue a seasonal awareness notification message that will alert
Navy ships and aircraft in the area of the possible presence of
whales and instruct them to remain vigilant to the presence of large
whales that when seasonally concentrated (like humpbacks) may become
vulnerable to vessel strikes. The message is issued to all vessels
in Hawaii from November through April. This message will further
increase the vigilance of Navy Lookouts in a place and time where
humpback whale density is high, which will further reduce the chance
that a humpback whale (or other large whale) may be struck.
Humpback Whale Special Reporting Areas: The Navy will report the
total hours of surface ship hull-mounted MFAS used between December
15 and April 15 in three special reporting areas, including Penguin
Banks and two other much smaller areas that also overlap the
humpback whale BIA. These reporting areas are not mitigation areas,
however, we describe them here because they were identified in order
to inform the adaptive management process. Specifically, Penguin
Bank is an area with high humpback whale density that is also
critical for Navy training and testing. Because of the
impracticability of implementing activity limitations in this
important area, we designated this reporting requirement so that
NMFS could remain aware of the level of activity in the area and
revisit mitigation discussions, if appropriate. To date the Navy's
reporting has not lead to changes in NMFS' least practicable adverse
impact analysis for the mitigation in this area.
Mitigation Areas Off the U.S. West Coast
Santa Barbara Island Mitigation Area (Year-round): The Navy will
not use ship hull-mounted MFAS during training or testing (the
source responsible for the most
[[Page 66971]]
take), or explosives during medium-calibre or large-calibre gunnery,
torpedo, bombing, and missile (including 2.75-inch rockets)
activities during training, year-round. The boundary of this
mitigation area is conterminous with the boundary of the portion of
the Channel Islands NMS that is within the HSTT Study Area, and
overlaps the extensive coastal gray whale migration BIA. The Channel
Islands NMS is considered a highly productive and diverse area of
high-value habitat that is more typically free of anthropogenic
stressors (because many activities are prohibited or limited within
the Sanctuary boundaries), and, therefore, limiting sonar and
explosive activities in this area would be expected to reduce the
likelihood that marine mammals feeding or resting in the area (which
is more likely because of the higher value habitat) would be
disrupted in a manner that would have adverse effects on their
energy budgets and potentially impact reproduction or survival, or
that marine mammals using the area would incur TTS or PTS. Activity
limitations in this mitigation area are considered protection of
generally higher quality habitat (because of the diversity of prey
species and protected space, including acoustic habitat, that is
generally freer from stressors) for the myriad marine mammal species
that use it or may pass through the area, which could include any of
the species identified as being present in the SOCAL portion of the
HSTT Study Area. Though the gray whale migration area primarily
consists of a relatively narrow coastal strip, some gray whales
migrate through this area, either north or south, in all months of
the year except August and September.
San Diego Arc, San Nicolas Island, and Santa Monica/Long Beach
Mitigation Areas: From June 1 through October 31, the Navy will not
conduct more than 200 hours of surface ship hull-mounted MFAS in
these combined areas during training or testing, and will limit
explosive use in the three areas as described in Table 66 below. The
San Diego Arc Mitigation Area is conterminous with the entirety of a
blue whale feeding BIA and the other two mitigation areas are
conterminous with the portions of two blue whale feeding BIAs that
overlap the HSTT Study Area. One blue whale feeding BIA in SOCAL is
not protected by a mitigation area (Tanner-Cortes Banks) because it
would be impracticable due to the significant importance of the area
for Navy testing and training (described in detail in the HSTT FEIS/
OEIS). All of these mitigation areas overlap the gray whale
migratory route. Reducing harassing exposures (behavioral
disturbance or hearing impairment) of marine mammals to sonar and
explosives in feeding areas, even when the animals have demonstrated
some tolerance for disturbance when in a feeding state, is expected
to reduce the likelihood that feeding would be interrupted to a
degree that energetic reserves might be affected in a manner that
could reduce survivorship or reproductive success. This mitigation
area will also partially overlap with an important migration area
for gray whales.
Blue whale (June-October), Gray Whale (November-March), and Fin
Whale (November-May) Awareness Notification Message Area: The Navy
will issue a seasonal awareness notification message that will alert
ships and aircraft in the area of the possible presence of whales
and instruct them to remain vigilant to the presence of large whales
that, when seasonally concentrated (like blue whales, gray whales,
or fin whales) may become vulnerable to vessel strikes. The message
is issued to all Navy vessels in SOCAL in the indicated time
periods. This message is will further increase the vigilance of Navy
Lookouts in a place and time where blue, gray, and fin whale density
is high, which will further reduce the chance that one of these
species (or other large whale) may be struck.
Information on the mitigation measures that the Navy will
implement within mitigation areas is provided in Tables 65 and 66.
The mitigation applies year-round unless specified otherwise in the
tables.
Mitigation Areas for the Hawaii Range Complex (HRC)
Mitigation areas for the HRC are described in Table 65 below.
The location of each mitigation area is depicted in Figures 1 and 2
above and may also be found in Chapter 5 of the 2018 HSTT FEIS/OEIS.
Table 65--Mitigation Areas for Marine Mammals in the Hawaii Range
Complex
------------------------------------------------------------------------
Mitigation area description
-------------------------------------------------------------------------
Stressor or Activity:
Sonar.
Explosives.
Vessel strikes.
Mitigation Area Requirements:
Hawaii Island Mitigation Area (year-round):
--Navy personnel must not conduct more than 300 hours of MF1 surface
ship hull-mounted mid-frequency active sonar or 20 hours of MF4
dipping sonar, or use explosives that could potentially result in
takes of marine mammals during training and testing. Should
national security require conduct of more than 300 hours of MF1
surface ship hull-mounted mid-frequency active sonar or 20 hours of
MF4 dipping sonar, or use of explosives that could potentially
result in the take of marine mammals during training or testing,
Naval units 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
the information (e.g., sonar hours or explosives usage) in its
annual activity reports submitted to NMFS.
4-Islands Region Mitigation Area (November 15-April 15 for
active sonar; year-round for explosives):
--Navy personnel must not use MF1 surface ship hull-mounted mid-
frequency active sonar or explosives that could potentially result
in takes of marine mammals during training and testing. Should
national security require use of MF1 surface ship hull-mounted mid-
frequency active sonar or explosives that could potentially result
in the take of marine mammals during training or testing, Naval
units 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
the information (e.g., sonar hours or explosives usage) in its
annual activity reports submitted to NMFS.
Humpback Whale Special Reporting Areas (December 15-April 15):
--Navy personnel must report the total hours of surface ship hull-
mounted mid-frequency active sonar used in the special reporting
areas in its annual training and testing activity reports submitted
to NMFS.
Humpback Whale Awareness Notification Message Area (November-
April):
--Navy personnel must issue a seasonal awareness notification
message to alert ships and aircraft operating in the area to the
possible presence of concentrations of large whales, including
humpback whales.
--To maintain safety of navigation and to avoid interactions with
large whales during transits, Navy personnel must instruct vessels
to remain vigilant to the presence of large whale species
(including humpback whales), that when concentrated seasonally, may
become vulnerable to vessel strikes.
--Platforms must use the information from the awareness notification
message to assist their visual observation of applicable mitigation
zones during training and testing activities and to aid in the
implementation of procedural mitigation.
------------------------------------------------------------------------
[[Page 66972]]
Mitigation Areas for the SOCAL Portion of the Study Area
Mitigation areas for the SOCAL portion of the Study Area are
described in Table 66 below. The location of each mitigation area is
depicted in Figures 3 and 4 above and may also be found in Chapter 5
of in the 2018 HSTT FEIS/OEIS.
Table 66--Mitigation Areas for Marine Mammals in the Southern California
Portion of the Study Area
------------------------------------------------------------------------
Mitigation area description
-------------------------------------------------------------------------
Stressor or Activity
Sonar.
Explosives.
Vessel strikes.
Mitigation Area Requirements:
San Diego Arc, San Nicolas Island, and Santa Monica/Long Beach
Mitigation Areas (June 1-October 31):
--Navy personnel must not conduct more than a total of 200 hours of
MF1 surface ship hull-mounted mid-frequency active sonar in the
combined areas, excluding normal maintenance and systems checks,
during training and testing. Should national security require
conduct of more than 200 hours of MF1 surface ship hull-mounted mid-
frequency active sonar in the combined areas during training and
testing (excluding normal maintenance and systems checks), naval
units 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
the information (e.g., sonar hours) in its annual activity reports
submitted to NMFS.
--Within the San Diego Arc Mitigation Area, Navy personnel must not
use explosives that could potentially result in the take of marine
mammals during large-caliber gunnery, torpedo, bombing, and missile
(including 2.75'' rockets) activities during training and testing.
Should national security require use of explosives that could
potentially result in the take of marine mammals during large-
caliber gunnery, torpedo, bombing, and missile (including 2.75''
rockets) activities during training or testing, naval units 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 the information (e.g.,
explosives usage) in its annual activity reports submitted to NMFS.
--Within the San Nicolas Island Mitigation Area, Navy personnel must
not use explosives that could potentially result in the take of
marine mammals during mine warfare, large-caliber gunnery, torpedo,
bombing, and missile (including 2.75'' rockets) activities during
training. Should national security require use of explosives that
could potentially result in the take of marine mammals during mine
warfare, large-caliber gunnery, torpedo, bombing, and missile
(including 2.75'' rockets) activities during training, Naval units
must obtain permission from the appropriate designated Command
authority prior to commencement of the activity. The Navy must
provide NMFS with advance notification and include the information
(e.g., explosives usage) in its annual activity reports submitted
to NMFS.
--Within the Santa Monica/Long Beach Mitigation Area, Navy personnel
must not use explosives that could potentially result in the take
of marine mammals during mine warfare, large-caliber gunnery,
torpedo, bombing, and missile (including 2.75'' rockets) activities
during training and testing. Should national security require use
of explosives that could potentially result in the take of marine
mammals during mine warfare, large-caliber gunnery, torpedo,
bombing, and missile (including 2.75'' rockets) activities during
training or testing, Naval units must obtain permission from the
appropriate designated Command authority prior to commencement of
the activity. Navy must provide NMFS with advance notification and
include the information (e.g., explosives usage) in its annual
activity reports submitted to NMFS.
Santa Barbara Island Mitigation Area (year-round):
--Navy personnel must not use MF1 surface ship hull-mounted mid-
frequency active sonar during training or testing, or explosives
that could potentially result in the take of marine mammals during
medium-caliber or large-caliber gunnery, torpedo, bombing, and
missile (including 2.75'' rockets) activities during training.
Should national security require use of MF1 surface ship hull-
mounted mid-frequency active sonar during training or testing, or
explosives that could potentially result in the take of marine
mammals during medium-caliber or large-caliber gunnery, torpedo,
bombing, and missile (including 2.75'' rockets) activities during
training, Naval units 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 the information (e.g., sonar hours or explosives usage) in
its annual activity reports submitted to NMFS.
Blue Whale (June-October), Gray Whale (November-March), and Fin
Whale (November-May) Awareness Notification Message Areas:
--Navy personnel must issue a seasonal awareness notification
message to alert ships and aircraft operating in the area to the
possible presence of concentrations of large whales, including blue
whales, gray whales, or fin whales.
--To maintain safety of navigation and to avoid interactions with
large whales during transits, Navy personnel must instruct vessels
to remain vigilant to the presence of large whale species, that
when concentrated seasonally, may become vulnerable to vessel
strikes.
--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.
------------------------------------------------------------------------
Summary of Mitigation
The Navy's mitigation measures are summarized in Tables 67
(Procedural Mitigation) and 68 (Mitigation Areas).
Summary of Procedural Mitigation
Table 67--Summary of Procedural Mitigation
------------------------------------------------------------------------
Mitigation zone sizes and other
Stressor or activity requirements
------------------------------------------------------------------------
Environmental Awareness and Education.. Afloat Environmental
Compliance Training program
for applicable personnel.
Active Sonar........................... Depending on sonar source:
1,000 yd power down,
500 yd power down, and 200 yd
shut down
200 yd shut down.
Air Guns............................... 150 yd.
Pile Driving........................... 100 yd.
Weapons Firing Noise................... 30[deg] on either side
of the firing line out to 70
yd.
Explosive Sonobuoys.................... 600 yd.
[[Page 66973]]
Explosive Torpedoes.................... 2,100 yd.
Explosive Medium-Caliber and Large- 1,000 y. (large-
Caliber Projectiles. caliber projectiles).
600 yd (medium-caliber
projectiles during surface-to-
surface activities).
200 yd (medium-caliber
projectiles during air-to-
surface activities).
Explosive Missiles and Rockets......... 2,000 yd (21-500 lb.
net explosive weight).
900 yd (0.6-20 lb. net
explosive weight).
Explosive Bombs........................ 2,500 yd.
Sinking Exercises...................... 2.5 nmi.
Explosive Mine Countermeasure and 2,100 yd (6-650 lb net
Neutralization Activities. explosive weight).
600 yd (0.1-5 lb net
explosive weight).
Explosive Mine Neutralization 1,000 yd (21-60 lb net
Activities Involving Navy Divers. explosive weight for positive
control charges and charges
using time-delay fuses).
500 yd (0.1-20 lb net
explosive weight for positive
control charges).
Underwater Demolition Multiple Charge-- 700 yd.
Mat Weave and Obstacle Loading.
Maritime Security Operations--Anti- 200 yd.
Swimmer Grenades.
Vessel Movement........................ 500 yd (whales).
200 yd (other marine
mammals).
Towed In-Water Devices................. 250 yd (marine
mammals).
Small-, Medium-, and Large-Caliber Non- 200 yd.
Explosive Practice Munitions.
Non-Explosive Missiles and Rockets..... 900 yd.
Non-Explosive Bombs and Mine Shapes.... 1,000 yd.
------------------------------------------------------------------------
Summary of Mitigation Areas
Table 68--Summary of Mitigation Areas for Marine Mammals
------------------------------------------------------------------------
Summary of mitigation area requirements
-------------------------------------------------------------------------
Mitigation Areas for Shallow-water Coral Reefs and Precious Coral Beds
(year-round)
The Navy must not conduct precision anchoring (except in
designated anchorages), explosive or non-explosive mine
countermeasure and neutralization activities, explosive or non-
explosive mine neutralization activities involving Navy divers,
explosive or non-explosive small-, medium-, and large-caliber
gunnery activities using a surface target, explosive or non-
explosive missile and rocket activities using a surface target, and
explosive or non-explosive bombing or mine laying activities
(except in designated locations).
The Navy must not place mine shapes, anchors, or mooring
devices on the seafloor (except in designated locations).
Hawaii Island Mitigation Area (year-round)
Navy personnel must not conduct more than 300 hours of MF1
surface ship hull-mounted mid-frequency active sonar or 20 hours of
MF4 dipping sonar, or use explosives that could potentially result
in takes of marine mammals during training and testing.\1\
4-Islands Region Mitigation Area (November 15-April 15 for active sonar;
year-round for explosives)
Navy personnel must not use MF1 surface ship hull-mounted
mid-frequency active sonar or explosives that could potentially
result in takes of marine mammals during training and testing.\1\
Humpback Whale Special Reporting Areas (December 15-April 15)
Navy personnel must report the total hours of surface ship
hull-mounted mid-frequency active sonar used in in the special
reporting areas in its annual training and testing activity reports
submitted to NMFS.
San Diego Arc, San Nicolas Island, and Santa Monica/Long Beach
Mitigation Areas (June 1-October 31)
Navy personnel must not conduct more than a total of 200
hours of MF1 surface ship hull-mounted mid-frequency active sonar
in the combined areas, excluding normal maintenance and systems
checks, during training and testing.\1\
Within the San Diego Arc Mitigation Area, Navy personnel
must not use explosives that could potentially result in the take
of marine mammals during large-caliber gunnery, torpedo, bombing,
and missile (including 2.75'' rockets) activities during training
and testing.\1\
Within the San Nicolas Island Mitigation Area, Navy
personnel must not use explosives that could potentially result in
the take of marine mammals during mine warfare, large-caliber
gunnery, torpedo, bombing, and missile (including 2.75'' rockets)
activities during training.\1\
Within the Santa Monica/Long Beach Mitigation Area, Navy
personnel must not use explosives that could potentially result in
the take of marine mammals during mine warfare, large-caliber
gunnery, torpedo, bombing, and missile (including 2.75'' rockets)
activities during training and testing.\1\
Santa Barbara Island Mitigation Area (year-round)
Navy personnel must not use MF1 surface ship hull-mounted
mid-frequency active sonar during training and testing, or
explosives that could potentially result in the take of marine
mammals during medium-caliber or large-caliber gunnery, torpedo,
bombing, and missile (including 2.75'' rockets) activities during
training.\1\
Awareness Notification Message Areas (seasonal according to species)
Navy personnel must issue awareness notification messages
to alert ships and aircraft to the possible presence of humpback
whales (November-April), blue whales (June-October), gray whales
(November-March), or fin whales (November-May).
------------------------------------------------------------------------
\1\ If Naval units need to conduct more than the specified amount of
training or testing, they will obtain permission from the appropriate
designated Command authority prior to commencement of the activity.
The Navy will provide NMFS with advance notification and include the
information in its annual activity reports submitted to NMFS.
[[Page 66974]]
Mitigation Conclusions
NMFS has carefully evaluated the Navy's mitigation measures--
many of which were developed with NMFS' input during the previous
phases of Navy training and testing authorizations, or during the
development of the proposed or final rule for these HSTT Phase 3
activities. NMFS and the Navy also considered a broad range of other
measures (i.e., the measures considered but eliminated, as discussed
in the HSTT FEIS/OEIS, which reflect many of the comments that have
arisen via public input in past years) to ensure that NMFS
prescribes the means of effecting the least practicable adverse
impact on the affected marine mammal species and stocks and their
habitat. In particular for this rule, we carefully and thoroughly
evaluated those additional measures that were put in place in 2015
as a result of the settlement agreement in Conservation Council for
Hawaii v. National Marine Fisheries Service. Our evaluation of
mitigation 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 and stocks and their habitat; the
proven or likely efficacy of the measures; and the practicability of
the measures for applicant implementation, including consideration
of personnel safety, practicality of implementation, and impact on
the effectiveness of the military readiness activity. Ultimately,
the Navy adopted all mitigation measures that are practicable by,
among other things, not jeopardizing its mission and Title 10
responsibilities. A comprehensive assessment by Navy leadership of
the final, entire list of mitigation measures concluded that the
inclusion of any further mitigation beyond those measures identified
here in the final rule would be entirely impracticable. NMFS
independently reviewed the Navy's practicability determinations for
specific mitigation areas and concurs with the Navy's analysis.
Based on our evaluation of the Navy's planned measures, as well
as other measures considered by the Navy and NMFS, NMFS has
determined that the mitigation measures included in this rule are
appropriate means of effecting the least practicable adverse impacts
on marine mammals species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of
similar significance, considering specifically personnel safety,
practicality of implementation, and impact on the effectiveness of
the military readiness activity.
Additionally, as described in more detail below, the final rule
includes an adaptive management provision, which ensures that
mitigation is regularly assessed and provides a mechanism to improve
the mitigation, based on the factors above, through modification as
appropriate.
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 HSTT Study Area for over 20 years, it developed a formal marine
species monitoring program in support of the MMPA and ESA
authorizations for the Hawaii and Southern California range
complexes 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,
rules, and 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) (www.seamap.env.duke.edu).
The Navy will continue collecting monitoring data to inform our
understanding of the occurrence of marine mammals in the HSTT Study
Area; the likely exposure of marine mammals to stressors of concern
in the HSTT 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, 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. Monitoring is
required under the MMPA, and details of the monitoring program for
the specified activities have been developed through coordination
between NMFS and the Navy through the regulatory process for
previous Navy at-sea training and testing actions.
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,
detailed and specific studies will be developed which support the
Navy's and NMFS top-level monitoring goals. 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:
[ssquf] An increase in our 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/or density of species);
[ssquf] An increase in our understanding of the nature, scope,
or context of the likely exposure of marine mammals and/or ESA-
listed species to any of the potential stressor(s) 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/or
(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);
[ssquf] An increase in our 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);
[ssquf] An increase in our 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 effects on annual rates of
recruitment or survival);
[ssquf] An increase in our understanding of the effectiveness of
mitigation and monitoring measures;
[ssquf] A better understanding and record of the manner in which
the authorized entity complies with the incidental take regulations
and LOAs and the ESA Incidental Take Statement;
[ssquf] An increase in the probability of detecting marine
mammals (through
[[Page 66975]]
improved technology or methods), both specifically within the
mitigation zone (thus allowing for more effective implementation of
the mitigation) and in general, to better achieve the above goals;
and
[ssquf] 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 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
would leverage 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 HSTT Study Area
The monitoring program has undergone significant changes since the
first rules were issued for HRC and SOCAL in 2009, which highlights its
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, 2008) 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 objective have continued through the latest permit cycle
through 2018.
Progress has also been made on the monitoring program's conceptual
framework categories from the Scientific Advisory Group for Navy Marine
Species Monitoring (U.S. Department of the Navy, 2011e), ranging from
occurrence of animals to their exposure, response, and population
consequences. Lessons-learned with monitoring in the first two MMPA
rulemaking periods in HRC and SOCAL suggested that ``layering''
multiple components of monitoring simultaneously provides a way to
leverage an increase in return of the progress toward answering
scientific monitoring questions.
Specific monitoring under the 2013-2018 regulations has included:
[ssquf] HRC
[cir] Long-term Trends in Abundance of Marine Mammals at the
Pacific Missile Range Facility (PMRF);
[cir] Estimation of Received Levels of Mid-Frequency Active
Sonar on Marine Mammals at PMRF;
[cir] Behavioral Response of Marine Mammals to Navy Training and
Testing at PMRF; and
[cir] Navy Civilian Marine Mammal Observers on MFAS Ships in
Offshore Waters of HRC.
[ssquf] SOCAL
[cir] Blue and Fin Whale Satellite Tagging;
[cir] Cuvier's Beaked Whale Impact Assessment at the Southern
California Offshore Antisubmarine Warfare Range (SOAR);
[cir] Cuvier's Beaked Whale, Blue Whale, and Fin Whale Impact
Assessments at Non-Instrumented Range Locations in SOCAL; and
[cir] Marine Mammal Sightings during California Cooperative
Oceanic Fisheries Investigation (CalCOFI) Cruises.
Numerous publications, dissertations, and conference presentations
have resulted from research conducted under the Navy's 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 analyses 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 of monitoring across all Navy at-sea
study areas, including study areas in the Pacific and the Atlantic
Oceans, and various testing ranges. Publications from the Living Marine
Resources and Office of Naval Research programs have also resulted in
significant contributions to hearing, acoustic criteria used in effects
modeling, exposure, and response, as well as 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 zone during Major Training
Exercises when mitigations are implemented. These data are provided to
NMFS in both classified and unclassified annual exercise reports.
NMFS has received multiple years' worth of annual exercise and
monitoring reports addressing active sonar use and explosive
detonations within the HSTT 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 HSTT Study Area. The Navy's
annual exercise and monitoring reports may be viewed at: http://www.nmfs.noaa.gov/pr/permits/incidental/military.htm and http://www.navymarinespeciesmonitoring.us.
The Navy has been funding various marine mammal studies and
research within the HSTT Study Area for the past 20 years. Under
permitting from NMFS starting in 2009, this effort has transitioned
from a specific metric based approach, to a broader new research only
approach (e.g., set number of visual surveys, specific number of
passive acoustic recording devices, etc.), and more recently since 2014
a more regional (Hawaii or Southern California) species-specific study
question design (e.g., what is distribution of species A within the
HSTT Study Area, what is response of species B to Navy activities,
etc.).
In adaptive management consultation with NMFS, some variation of
these ongoing studies or planned new studies will continue within the
HSTT Study Area for either the duration of these new regulations, or
for a set period as specified in a given project's scope. Some projects
may only require one or two years of field effort. Other projects
[[Page 66976]]
could entail multi-year field efforts (two to five years). For
instance, in the SOCAL portion of the HSTT Study Area, the Navy has
funded development and application of new passive acoustic technology
since the early 2000's for detecting Cuvier's beaked whales. This also
includes ongoing effort to further identify and update population
demographics for Cuvier's beaked whales (re-sighting rates, population
growth, calving rates, movements, etc.) specific to Navy training and
testing areas, as well as responses to Navy activity. Variations of
these Cuvier's beaked whale monitoring studies will likely continue
under future authorizations. 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/.
The Navy's marine species monitoring program typically supports 6-
10 monitoring projects in the HSTT Study Area at any given time.
Projects can be either major multi-year efforts, or one to two year
special studies. The Navy's monitoring projects going into 2019
include:
[ssquf] Long-term Trends in Abundance of Marine Mammals at PMRF
(Hawaii)--Analysis of long-term archive of hydrophone recordings
from the instrumented range at PMRF to uncover long-term trends in
the occurrence of marine mammals on the range, including minke
whale, humpback whale, fin whale, Bryde's whale, and Blainville's
beaked whale.
[ssquf] Estimation of Received Levels of MFAS and an
opportunistic Behavioral Response Study of Marine Mammals at PMRF
(Hawaii)--Estimation of the received level of mid-frequency active
sonar (MFAS) of marine mammals (including blackfish species,
mysticetes, sperm whale, and beaked whales) near PMRF as well as
their short-term behavioral responses. Analysts will perform
acoustic propagation modeling from Navy platforms to localized
animals. Animals may be localized either acoustically by the range
hydrophones, or by a satellite tagging effort. The tagging component
will also provide information on spatial movement and habitat-use
patterns. Both received-level and behavioral response studies will
be an opportunistic protocol performed during actual Navy training
deploying MFAS.
[ssquf] Humpback Whale Tagging at PMRF (Hawaii)--A combination
of acoustic pinger and satellite tags will be applied to humpback
whales to investigate the movement patterns, habitat use, and
behavior of humpback whales (nearshore and offshore) of different
age-sex classes on and off the instrumented range at PMRF. The tags
will also enable enhanced validation of localization algorithms
using the range hydrophones, as well as provide locations of animals
when they are not vocalizing.
[ssquf] Navy Civilian Marine Mammal Observers on guided missile
destroyers (DDGs) (Hawaii and Southern California)--Visual survey
for marine mammals will be performed by biologist observers embarked
aboard Navy DDGs during training exercises involving deployment of
MFAS. The acquired data will be incorporated in a long-term project
investigating the mitigation effectiveness of Navy Lookouts that
spans all Navy at-sea training ranges in both the Atlantic and
Pacific oceans.
[ssquf] Cuvier's Beaked Whale Impact Assessment at SOAR
(Southern California)--The instrumented hydrophone range at the
Navy's Southern California Antisubmarine Warfare Range (SOAR),
combined with concurrent field efforts with satellite tagging and
visual surveys will investigate key baseline population demographics
and movement patterns for Cuvier's beaked whale. Short-term
behavioral and/or vocal responses when Cuvier's beaked whales are
exposed to sonar will also be investigated.
[ssquf] Beaked Whale Occurrence In Southern California From
Passive Acoustic Monitoring (Southern California)--This project has
three field components. Bottom-moored passive acoustic devices will
investigate the seasonality and spatial distribution of beaked whale
species in Southern California including new deployments in Baja.
Also, ocean profiling gliders outfitted with a high frequency
acoustic recording system will perform a survey on a larger
geographic scale and across a diverse range of habitats in Southern
California to investigate the spatial distribution and occurrence of
beaked whale species. Finally, passive acoustic data from towed
arrays deployed during quarterly California Cooperative Oceanic
Fisheries Investigations surveys will be analyzed for beaked whales
across a large geographic scale.
[ssquf] Guadalupe Fur Seal Population Census and Satellite
Tracking (Southern California)--Satellite tagging as well as land-
based visual survey will investigate the habitat use by age-sex
class of Guadalupe fur seals across both the Southern California
Range Complex and Northwest Training and Testing study areas, as
well as other areas including epipelagic waters.
[ssquf] Blue and Fin Whale Satellite Tagging and Genetics
(Southern California)--Satellite tagging of blue whales and fin
whales at various locations off southern California occurred from
2014-2017. The project investigated movement patterns, occurrence,
and residence times of blue and fin whales within Navy training and
testing areas along the U.S. West Coast as compared to other areas
visited by tagged whales outside of Navy training and testing areas.
While field efforts for this project are complete, additional
analysis will continue beyond 2018 and include peer-reviewed result
publication.
Additional scientific projects may have field efforts within Hawaii
and Southern California under separate Navy funding from the Navy's two
marine species research programs, the Office of Naval Research Marine
Mammals and Biology Program and the Living Marine Resources Program.
The periodicity of these research projects are more variable than the
Navy's compliance monitoring described above.
Adaptive Management
The final regulations governing the take of marine mammals
incidental to Navy training and testing activities in the HSTT 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 five-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 would 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 LOA 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 exercises reports, as required by MMPA
authorizations; (2) compiled results of Navy funded R&D 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 an incidental take authorization for an activity,
section
[[Page 66977]]
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 would be
posted to the Navy's Marine Species Monitoring web portal: http://www.navymarinespeciesmonitoring.us. Currently, there are several
different reporting requirements pursuant to these regulations:
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 for review at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.
Annual HSTT Monitoring Report
The Navy will submit an annual report to NMFS of the HSTT
monitoring describing the implementation and results from the previous
calendar year. Data collection methods will be standardized across
range complexes and HSTT Study Area to allow for comparison in
different geographic locations. The draft of the annual monitoring
report will be submitted either three months after the calendar year,
or three months after the conclusion of the monitoring year to be
determined by the Adaptive Management process. Such a report would
describe progress of knowledge made with respect to intermediate
scientific objectives within the HSTT Study Area associated with the
Integrated Comprehensive Monitoring Program. Similar study questions
will be treated together so that summaries can be provided for each
topic area. The report need not include analyses and content that do
not provide direct assessment of cumulative progress on the monitoring
plan study questions. NMFS will submit comments 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 the submittal of the draft if NMFS does not have comments.
As an alternative, the Navy may submit a multi-Range Complex annual
Monitoring Plan report to fulfill this requirement. Such a report will
describe progress of 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
will be 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 study question. This will
continue to allow Navy to provide a cohesive monitoring report covering
multiple ranges (as per ICMP goals), rather than entirely separate
reports for the HSTT, Gulf of Alaska, Mariana Islands, and the
Northwest Study Areas.
Annual HSTT Training Exercise Report and Testing Activity Report
Each year, the Navy will submit two preliminary reports (Quick Look
Reports) to NMFS detailing the status of authorized sound sources
within 21 days after the anniversary of the date of issuance of the
LOAs. Each year, the Navy will also submit detailed reports to NMFS
within three months after the one-year anniversary of the date of
issuance of the LOAs. The annual reports will contain information on
MTEs, Sinking Exercise (SINKEX) events, and a summary of all sound
sources used (total hours or quantity (per the LOA) of each bin of
sonar or other non-impulsive source; total annual number of each type
of explosive exercises; and total annual expended/detonated rounds
(missiles, bombs, sonobuoys, etc.) for each explosive bin). The report
will also include the details regarding specific requirements
associated with specific mitigation areas. The analysis in the detailed
reports will be based on the accumulation of data from the current
year's report and data collected from previous reports. Information
included in the classified annual reports may be used to inform future
adaptive management of activities within the HSTT Study Area.
The Annual HSTT Training Exercise Report and Testing Activity Navy
reports (classified or unclassified versions) can be consolidated with
other exercise reports from other range complexes in the Pacific Ocean
for a single Pacific Exercise Report, if desired. Specific sub-
reporting in these annual reports include:
[ssquf] Humpback Whale Special Reporting Area (December 15-April
15): The Navy will report the total hours of operation of surface
ship hull-mounted mid-frequency active sonar used in the special
reporting area; and
[ssquf] HSTT Mitigation Areas (see Chapter 11 of the Navy's
rulemaking/LOA application): The Navy will report any use of surface
ship hull-mounted mid-frequency active sonar that occurred as
specifically described in these areas.
[ssquf] Major Training Exercises Notification
The Navy shall submit an electronic report to NMFS within fifteen
calendar days after the completion of any major training exercise
indicating: Location of the exercise; beginning and end dates of the
exercise; and type of exercise.
Other Reporting and Coordination
The Navy will continue to report and coordinate with NMFS for the
following:
[ssquf] Annual marine species monitoring technical review
meetings with researchers and the Marine Mammal Commission
(currently, every two years a joint Pacific-Atlantic meeting is
held); and
[ssquf] Annual Adaptive Management meetings with the Marine
Mammal Commission (recently modified to occur in conjunction with
the annual monitoring technical review meeting).
Analysis and Negligible Impact Determination
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 addition to
considering estimates of the number of marine mammals that might be
``taken'' through mortality, serious injury, and Level A or Level B
harassment (as presented in Tables 41 and 42), NMFS considers other
factors, such as the likely nature of any responses (e.g., intensity,
duration), 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
[[Page 66978]]
impacts on the environmental baseline (e.g., as reflected in the
regulatory status of the species, population size and growth rate where
known, other ongoing sources of human-caused mortality, ambient noise
levels, and specific consideration of take by Level A harassment or
serious injury or mortality (hereafter referred to as M/SI) previously
authorized for other NMFS activities).
In the Estimated Take of Marine Mammals section, we identified the
subset of potential effects that would be expected to rise to the level
of takes, and then identified the number of each of those mortality
takes that we believe could occur or harassment takes that are likely
to occur based on the methods described. The impact that any given take
will have 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-level impacts to individuals, etc.). Here we evaluate the
likely impacts of the enumerated harassment takes that are proposed for
authorization and anticipated to occur under this rule, in the context
of the specific circumstances surrounding these predicted takes. We
also include a specific assessment of serious injury or mortality takes
that could occur, as well as consideration of the traits and statuses
of the affected species and stocks. Last, we collectively evaluate this
information, as well as other more taxa-specific information and
mitigation measure effectiveness, in group-specific discussions that
support our negligible impact conclusions for each stock.
Harassment
The Navy's Specified Activities reflect representative levels/
ranges of training and testing activities, accounting for the natural
fluctuation in training, testing, and deployment schedules. This
approach is representative of how the Navy's activities are conducted
over any given year over any given five-year period. Specifically, the
Navy provided a range of levels for each activity/source type for a
year--they used the maximum annual level to calculate annual takes, and
they used the sum of three nominal years (average level) and two
maximum years to calculate five-year takes for each source type. The
Description of the Specified Activity section contains a more realistic
annual representation of activities, but includes years of a higher
maximum amount of training and testing to account for these
fluctuations. There may be some flexibility in the exact number of
hours, items, or detonations that may vary from year to year, but take
totals would not exceed the five-year totals indicated in Tables 41 and
42. We base our analysis and negligible impact determination (NID) on
the maximum number of takes that would be reasonably expected to occur
and are being 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 immediately below that
applies to all the species listed in Tables 41 and 42, 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. However, below that, we break our analysis into species (and/or
stock), 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 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.
The Navy's harassment take request is based on its model and
quantitative assessment of mitigation, which NMFS believes
appropriately predicts that maximum amount of harassment that is likely
to occur. In the discussions below, the ``acoustic analysis'' refers to
the Navy's modeling results and quantitative assessment of mitigation.
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 (https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities), 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). The estimated number of Level A and Level B
harassment takes 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 and Level B
harassment threshold) that are anticipated to occur over the five-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
(meaning over multiple days) over the course of the year, while some
members of a species or stock may not experience take at all, which
means that the number of individuals taken is smaller than the total
estimated takes. In other words, where the instances of take exceed the
number of individuals in the population, repeated takes (on more than
one day) of some individuals are predicted. 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
[[Page 66979]]
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 stock
is being taken by Navy activities, 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 or more likely sequential. In
the ocean, 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, for some individuals of some stocks repeated
exposures across different activities could occur over the year,
especially where events occur in generally the same area with more
resident species. In short, for some stocks we expect that the total
anticipated takes represent exposures of a smaller number of
individuals of which some were 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 species or stocks
would be taken over more than a few sequential days. This means that
even where repeated takes of individuals are likely to occur, they are
more likely to result from non-sequential exposures from different
activities, and, even if sequential, individual animals are not
predicted to be taken for more than several days in a row, at most. As
described elsewhere, the nature of the majority of the exposures would
be expected to be of a less severe nature and based on the numbers it
is likely that any individual exposed multiple times is still only
taken on a small percentage of the days of the year. The greater
likelihood is that not every individual is taken, or perhaps a smaller
subset is taken with a slightly higher average and larger variability
of highs and lows, but still with no reason to think that any
individuals would be taken a significant portion of the days of the
year, much less that many of the days of disturbance would be
sequential.
Some of the lower level physiological stress responses (e.g.,
orientation or startle response, change in respiration, change in heart
rate) discussed earlier 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. Level B harassment takes, 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.
The estimates calculated using the behavioral response function do
not differentiate between the different types of behavioral responses
that rise to the level of Level B harassments. 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 that are used to predict how many instances
of Level B behavioral harassment 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 testing and training
activities would be primarily from ASW events. It is important to note
that although ASW is one of the warfare areas of focus during MTEs,
there are significant periods when active ASW sonars are not in use.
Nevertheless, behavioral reactions are assumed more likely to be
significant during MTEs than during other ASW activities due to the
duration (i.e., multiple days), scale (i.e., multiple sonar platforms),
and use of high-power hull-mounted sonar in the MTEs. In other words,
in the range of potential behavioral effects that might expect to be
part of a response that qualifies as an instance of Level B behavioral
harassment (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, that 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 when the 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 HSTT
Study Area, the Navy provided information estimating the percentage of
animals that may be taken by Level B harassment under each behavioral
response function 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 important
also. The majority of Level B harassment takes 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 or at closer proximity to the source. Because
stocks belonging to the same species and species belonging to taxa that
share common characteristics are likely to respond and be affected in
similar ways, these discussions are presented within each species group
below in the Group and Species-Specific Analyses section. 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
[[Page 66980]]
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).
Moore and Barlow (2013) emphasizes the importance of context (e.g.,
behavioral state of the animals, distance from the sound source, etc.)
in evaluating behavioral responses of marine mammals to acoustic
sources.
Diel Cycle
As noted previously, 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 diel cycle or recur
on subsequent days (Southall et al., 2007). 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
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 HSTT FEIS/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, 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 proposed for the HSTT Study Area generally last for only
a few hours. Some ASW training and testing can generally last for 2-10
days, or as much as 21 days for an MTE-Large Integrated ASW (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, the explosive component of the activity
only lasts for minutes (see Tables 4 through 7). 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. Although SINKEXs
may last for up to 48 hrs (4-8 hrs, possibly 1-2 days), they are almost
always completed in a single day and only one event is planned annually
for the HSTT training activities. They are stationary and conducted in
deep, open water where fewer marine mammals would typically be expected
to be encountered. They also have shutdown procedures and rigorous
monitoring, i.e., during the activity, the Navy conducts passive
acoustic monitoring and visually observes for marine mammals 90 min
prior to the first firing, during the event, and 2 hrs after sinking
the vessel. 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
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 can use to help better understand the overall
scope of the impacts is to compare these total instances of take
against the abundance of that stock. For example, if there are 100
harassment takes in a population of 100, one can assume either that
every individual was exposed above acoustic thresholds in no more than
one day, or that some smaller number were exposed in one day but a few
of those individuals were exposed multiple days within a year. Where
the instances of take exceed 100 percent of the population, 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 larger
portions of the stocks are 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 stock.
[[Page 66981]]
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 would likely occur over
the year, especially where numerous activities occur in generally the
same area (for example on instrumented ranges) with more resident
species. In short, we expect that the total anticipated takes represent
exposures of a smaller number of individuals of which some would 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 several
sequential days (with a few possible exceptions discussed in the stock-
specific conclusions).
When calculating the proportion of a population affected by takes
(e.g., the number of takes divided by population abundance), which can
also be helpful in estimating 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
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. In the case of
both Hawaii and Southern California (near which mutually exclusive sets
of stocks are impacted by Navy activities), the areas of Navy
activities across which take is estimated have boundaries that vary
significantly from the U.S. EEZ boundaries, and further vary
differently in Hawaii versus Southern California. For example, the
Study Area encompasses large areas of ocean space outside U.S. waters
(i.e., extending seaward beyond the U.S. EEZ) or, separately, many
stocks range up and down the U.S., Canada, and/or Mexican West Coast,
while Navy activities covered in this rule are confined north-south to
the Southern California area included in the Navy study area.
Additionally, the information used to estimate take includes the data
underlying the SAR abundances, as well as other survey data, used
together to model density layers. If takes are calculated from another
dataset (for example a broader sample of survey data) and compared to
the population estimate from the SARs, it may distort the percent of
the population affected or an assessment of how many days a year
individuals may be taken because of different population baselines.
However, when the SAR considers the larger area within which the stock
ranges it may contribute to a more appropriate sense of the proportion
of the population taken. Accordingly, in calculating the percentage of
takes versus abundance for each stock in order to assist in
understanding both the percentage of the 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 Hawaii, a fair number of stocks range outside of the U.S. EEZ,
the majority of the take occurs inside the U.S. EEZ, and a fair number
of stocks do not have abundance estimates in the SAR. Therefore, for
the purposes of this analytical exercise, the tables included in the
group-specific analyses below include percentages calculated for the
Navy's take in the U.S. EEZ versus the Navy-estimated abundances within
the U.S. EEZ, as well as the take in the whole Study Area versus the
Navy-estimated abundances in the whole area. However, where appropriate
for a given stock (and the explanation will be provided in the
narrative), the SAR abundance may also be used for comparison. For
Southern California, while a fair number of stocks range seaward from
the U.S. EEZ, many also range significantly north and south outside the
Navy Study Area and that abundance is captured by the SAR.
Additionally, generally speaking, except where stocks are more coastal,
a higher percentage of the take occurs outside of the U.S. EEZ than
around Hawaii (though the majority are still inside the U.S. EEZ).
Accordingly, rather than focus on the take in the U.S. EEZ, the tables
included in the group-specific analyses below include percentages
calculated for the Navy's take in the entire Study Area as compared
against both the Navy-calculated abundance in the entire Study Area and
the SARs.
The estimates found in NMFS' SARs remain the official estimates of
stock abundance where they are current. These estimates are typically
generated from the most recent shipboard and/or aerial surveys
conducted. Studies based on abundance and distribution surveys
restricted to U.S. waters are unable to detect temporal shifts in
distribution beyond U.S. waters that might account for any changes in
abundance within U.S. waters. 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 Navy's study
area (e.g., populations with distribution along the entire California
Current versus just SOCAL), comparisons to the SAR may be more
appropriate. This is because the Navy's acoustic modeling process does
not horizontally move animats, and therefore does not account for
immigration and emigration within the study area. For instance, while
it may be accurate that the abundance of animals in Southern California
at any one time for a particular species is 200 individuals, if the
species is highly migratory or has large daily home ranges, it is not
likely that the same 200 individuals would be present every day. A good
descriptive example is blue whales, which tagging data have shown
traverse the SOCAL area in a few 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 cycle
through SOCAL. Therefore, when comparing the estimated takes to an
abundance, in this case the SAR, which represents the total population,
may be more appropriate than the Navy's modeled abundance for SOCAL. In
each of the species write-ups for the negligible impact assessment we
explain which abundance was used for making the comparison of takes to
the impacts to the population.
NMFS' Southwest Fisheries Science Center derived densities for the
Navy, and NMFS supports the use of spatially and temporally explicit
density models that vary in space and time to estimate their potential
impacts to species. See the U.S. Navy Marine Species Density Database
Phase III Hawaii-Southern California Training and Testing Area
Technical Report to learn more on how the Navy selects density
information and the models selected for individual species. These
models may better characterize how Navy impacts can vary in space and
time but often predict different population abundances than the SARs.
Models may predict different population abundances for many
reasons. The models may be based on different data sets or different
temporal predictions may be made. The SARs are often based on single
years of NMFS surveys, whereas the models used by the Navy generally
include multiple years of survey data from NMFS, the Navy, and other
sources. To present a single, best estimate, the SARs often use a
single season survey where they have the best spatial coverage
(generally Summer). Navy models often use
[[Page 66982]]
predictions for multiple seasons, where appropriate for the species,
even when survey coverage in non-Summer seasons is limited, to
characterize impacts over multiple seasons as Navy activities may occur
in any season. Predictions may be made for different spatial extents.
Many different, but equally valid, habitat and density modeling
techniques exist and these can also be the cause of differences in
population predictions. Differences in population estimates may be
caused by a combination of these factors. Even similar estimates should
be interpreted with caution and differences in models should be fully
understood before drawing conclusions.
Temporary Threshold Shift
NMFS and the Navy have estimated that some individuals of some
species of marine mammals may sustain some level of TTS from active
sonar. As mentioned previously, 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 72-77 indicate the number of takes by TTS that may be
incurred by different stocks from exposure to active sonar and
explosives. The modeling predicts that no TTS will result from air guns
or pile driving activities. 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). TTS from explosives would be broadband. 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.
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 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
(MFAS), emits a ping typically every 50 seconds, incurring those levels
of TTS is highly unlikely. 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 6dB 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 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 HSTT Study
Area, it is unlikely that marine mammals would ever sustain a TTS from
MFAS that 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 (the source from which TTS would
most likely be sustained because the higher source level and slower
attenuation make it more likely that an animal would be exposed to a
higher received level) would not usually span the entire frequency
range of one vocalization type, much less span all types of
vocalizations or other critical auditory cues.
Tables 72-77 indicate the number of incidental takes by TTS 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 LF or HF
sonar 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
[[Page 66983]]
taken individual will have slightly diminished hearing sensitivity
(slightly more than natural variation, but nowhere near total deafness)
more often 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, for example, 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 Navy activities would result in
behavioral changes or other impacts that would impact any individual's
(of any hearing sensitivity) reproduction or survival.
Acoustic 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
(and potential secondary arrivals of indirect rays) versus TTS, which
continues beyond the duration of the signal. Fundamentally, masking is
referred to as a chronic effect because one of the key 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
species involved in this rule, we do not expect the exposures with the
potential for masking to be of a long duration. In addition, 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, such as shipping or seismic airgun
operation (the latter signal changes from intermittent to continuous at
distance), 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 ping every 50 seconds for
hull-mounted sources. 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. For the majority of
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 (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 one second,
masking would not occur. Additionally, 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 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. 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.
Masking could occur briefly in mysticetes due to the overlap
between their low-frequency vocalizations and the dominant frequencies
of airgun pulses. However, masking in odontocetes or pinnipeds is less
likely
[[Page 66984]]
unless the airgun activity is in close range when the pulses are more
broadband. Masking is more likely to occur in the presence of
broadband, relatively continuous noise sources such as during vibratory
pile driving and from vessels, however, the duration of temporal and
spatial overlap with any individual animal and the spatially separated
sources that the Navy uses would not be expected to result in more than
short-term, low impact masking that would not affect reproduction or
survival.
The other sources used in Navy training and testing, 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 and not expected to have adverse impacts on reproductive success
or survivorship.
PTS From Sonar Acoustic Sources and Explosives and Tissue Damage From
Explosives
Tables 72-77 indicate the number of individuals of each of species
and stock for which Level A harassment in the form of PTS resulting
from exposure to active sonar and/or explosives is estimated to occur.
Tables 72-77 also indicate the number of individuals of each species
and stock for which Level A harassment in the form of tissue damage
resulting from exposure to explosive detonations is estimated to occur.
The number of individuals to potentially incur PTS annually (from sonar
and explosives) for the predicted species ranges from 0 to 209 (209 is
for Dall's porpoise), but is more typically 0-10 (with the exception of
several other species that range up to 97). Only five stocks (three
dolphins and two pinnipeds) have the potential to incur tissue damage
from explosives and the number of individuals from any given stock
ranges from one to ten.
NMFS believes 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
believes 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, the Navy utilized a post-modeling quantitative
assessment to adjust the take estimates based on avoidance and the
likely success of some portion of the mitigation measures. As is
typical in predicting biological responses, it is challenging to
predict exactly how avoidance and mitigation will affect the take of
marine mammals, and therefore the Navy erred on the side of caution in
choosing a method that would more likely still overestimate the take by
PTS to some degree. Nonetheless, these modified Level A harassment take
numbers represent the maximum number of instances in which marine
mammals would be reasonably expected to incur either PTS or tissue
damage, 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 mentioned 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 region (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. Regardless of the frequency band though,
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.
We also assume that the acoustic exposures sufficient to trigger
onset PTS (or TTS) would be accompanied by physiological stress
responses, although the sound characteristics that correlate with
specific stress responses in marine mammals are poorly understood. As
discussed above for Level B behavioral harassment, we would not expect
the Navy's generally short-term, intermittent, and (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.
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 aerial 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 200 yds (183 m) to 2,500 yds (2,286 m) depending on the source
(e.g., explosive sonobuoy, explosive torpedo, explosive bombs), and 2.5
nmi for sinking exercise (see Tables 48-57).
We analyze the type and amount of take by Level A harassment in
Tables 39 through 41. Generally speaking, tissue damage injuries from
explosives could range from minor lung injuries (the most sensitive
organ and first to be affected) that consist of some short-term
reduction of health and fitness immediately following the injury that
heals quickly and will not have any discernible long-term effects, up
to more impactful permanent injuries across multiple organs that may
cause health problems and negatively impact reproductive success (i.e.,
increase the time between pregnancies or even render reproduction
unlikely) but fall just short of a ``serious injury'' by virtue of the
fact that the animal is not expected to die. Nonetheless, due to the
Navy's mitigation and detection capabilities, we would not expect
marine mammals to typically be exposed to a more severe blast located
closer to the source--so the impacts
[[Page 66985]]
likely would be on the less severe end. It is still difficult to
evaluate how these injuries may or may not impact an animal's fitness,
however, these effects are only seen in very small numbers (single
digits with the exception of two stocks) and in species of fairly high
to very high abundances. In short, it is unlikely that any, much less
all, of the small number of injuries accrued to any one stock would
result in reduced reproductive success of any individuals, but even if
a few did, the status of the affected stocks are such that it would not
be expected to adversely impact rates of reproduction (and PTS of the
low severity anticipated here is not expected to affect the survival of
any individual marine mammals).
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 or as a
result of marine mammal exposure to explosive detonations. We note here
that the takes from potential ship strikes or explosive exposures
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 HSTT 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 authorize incidental take through
multi-year regulations, nor does its companion provision at
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
[[Page 66986]]
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
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 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 101(a)(5)(A). As noted by NMFS and the U.S. Fish and
Wildlife Service in our implementation 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 the 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 Proposed and Final Rules (83 FR
57076; November 14, 2018). 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
[[Page 66987]]
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
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 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). As PBR is
applied by NMFS, it provides that growth toward OSP is not reduced by
more than 10 percent, which 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 Eastern North Pacific stock of blue
whales and the CA/OR/WA stock of humpback whales), 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 (e.g., the regulatory definition of ``negligible impact'' at 50
CFR 216.103 applies only to activities other than commercial fishing),
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. 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.'' This
criterion addresses when total human-caused mortality is exceeding PBR,
but the activity being assessed is responsible for only a small portion
of the mortality. In the HSTT proposed rule and other incidental take
authorizations in which NMFS has recently articulated a fuller
description of how we consider PBR under section 101(a)(5)(A), this
situation had not arisen, and NMFS' description of how we consider PBR
in the section 101(a)(5) authorization process did not, therefore,
include consideration of this scenario.
[[Page 66988]]
However, the analytical framework we use here appropriately
incorporates elements of the one 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 the 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
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). We must also determine, though, that 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 to result in adverse effects on the species or stock
through effects on annual rates of recruitment or survival.
As discussed above, however, 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, including
because, 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).
Our evaluation of the M/SI for each of the species and stocks for
which mortality or serious injury could occur follows. No mortalities
or serious injuries are anticipated from the Navy's sonar activities.
In addition, all mortality authorized for some of the same species or
stocks over the next several years pursuant to our final rulemaking for
the NMFS Southwest and Pacific Islands Fisheries Science Centers has
been incorporated into the residual PBR.
We first consider maximum potential incidental M/SI from the Navy's
ship strike analysis for the affected mysticetes and sperm whales (see
Table 69) and from the Navy's explosive detonations for California sea
lions and short-beaked common dolphin (see Table 70) 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 potential incremental addition of M/SI through Navy's
ship strikes and explosive detonations may affect the species' or
stocks' 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 may occur over the course of the
five-year rule. The rule authorizes no more than two from any of the
following species/stocks over the five-year period: gray whale (Eastern
North Pacific stock), fin whale (CA/OR/WA stock), and humpback whale
(Central North Pacific stock). The rule authorizes no more than one
mortality from any of the following species/stocks over the five-year
period: blue whale (Eastern North Pacific stock), humpback whale (CA/
OR/WA stock, Mexico DPS), and sperm whale (Hawaii stock). We do not
anticipate, nor authorize, ship strike takes to blue whale (Central
North Pacific stock), fin whale (Hawaii stock), gray whale (Western
North Pacific stock), minke whale (either CA/OR/WA stock or Hawaii
stock), sei whale (either Hawaii stock or Eastern North Pacific stock),
Bryde's whale (either Hawaii stock or Eastern Tropical Pacific stock)
or sperm whale (CA/OR/WA stock). This means an annual average of 0.2
whales from each species or stock where one mortality may occur and an
annual average of 0.4 whales from each species or stock where two
mortalities may occur as described in Table 69 (i.e., 1 or 2 takes over
5 years divided by 5 to get the annual number) is authorized.
Table 69--Summary Information Related to Mortalities Requested for Ship Strike, 2018-2023
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Annual
authorized Residual
Stock take by Total Fisheries interactions Vessel collisions (Y/N); PBR-PBR Recent UME (Y/N);
Species (stock) abundance serious annual M/ (Y/N); annual rate of M/ annual rate of M/SI from PBR * minus Stock trend * \4\ number and year
(Nbest) * injury or SI * \2\ SI from fisheries vessel collision* annual M/SI (since 2007)
mortality interactions * \3\
\1\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Fin whale (CA/OR/WA stock)......... 9,029 0.4 >=43.5 Y; >=0.5................ Y, 1.6.................. 81 37.5 [uarr]............... N.
Gray whale (Eastern North Pacific 26,960 0.4 138 Y, 7.7.................. Y, 0.8.................. 801 663 stable since 2003.... N.
stock).
Humpback whale (CA/OR/WA stock, 2,900 0.2 >=38.6 Y; >=14.1............... Y, 22................... 16.7 -21.9 [uarr]............... N.
Mexico DPS).
Humpback whale (Central North 10,103 0.4 40.76 Y; 18.76................ Y, 22................... 33.4 -7.36 stable............... N.
Pacific stock).
Sperm whale (Hawaii stock)......... 5,559 0.2 0.7 Y, 0.7.................. N....................... 13.9 13.2 ?.................... N.
[[Page 66989]]
Blue whale (Eastern North Pacific 1,647 0.2 >=19 >=0.96.................. Y, 18................... 2.3 -16.7 stable............... Y; 3, 2007.
Stock).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* Presented in the SARS.
\1\ This column represents the annual take by serious injury or mortality by vessel collision and was calculated by the number of mortalities for authorization divided by five 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 Navy strikes or NMFS' Southwest Fisheries Science Center (SWFSC) takes in the SARs to ensure not double-counted against PBR. However, for these species, there were no takes from
either other Navy activities or SWFSC in the SARs to deduct that would be considered double-counting.
\3\ This value represents the calculated PBR less the average annual estimate of ongoing anthropogenic mortalities (i.e., total annual human-caused M/SI, which is presented in the SARs).
\4\ See relevant SARs for more information regarding stock status and trends.
The Navy has also requested a small number of takes by serious
injury or mortality from explosives. To calculate the annual average of
mortalities for explosives in Table 70 we used the same method as
described for vessel strikes. The annual average is the total number of
takes divided by five years to get the annual number. Specifically,
NMFS is authorizing the following serious injury or mortality takes
from explosions: 4 California sea lions and 6 short-beaked common
dolphins over the 5-year period (therefore 0.8 mortalities annually for
California sea lions and 1.2 mortalities annually for short-beaked
common dolphin), as described in Table 70.
Table 70--Summary Information Related to Mortalities From Explosives, 2018-2023
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual
authorized Fisheries SWFSC Residual
Stock take by Total interactions (Y/N); authorized PBR--PBR Stock
Species (stock) abundance serious annual M/ annual rate of M/SI PBR * take minus trend * UME (Y/N);
(Nbest) * injury or SI * \2\ from fisheries (annual) annual M/SI \5\ number and year
mortality * interactions * \3\ and SWFSC
\1\ \4\
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion (U.S. 257,606 0.8 318.4 Y; 197............. 14,011 6.6 13,686 [uarr] Y; 2013.
stock).
Short-beaked common dolphin 969,861 1.2 >=40 Y; >=40............ 8,393 2.8 8,350.2 ? N.
(CA/OR/WA stock).
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Presented in the SARS.
\1\ This column represents the annual take by serious injury or mortality during explosive detonations and was calculated by the number of mortalities
planned for authorization divided by five 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 Navy activities or NMFS' SWFSC takes in the SARs to ensure not double-counted against PBR. In this
case, for California sea lion 0.8 annual M/SI from the U.S. West Coast during scientific trawl and longline operations conducted by NMFS and 1.8
annual M/SI from marine mammal research related mortalities authorized by NMFS was deducted from total annual M/SI (321).
\3\ This column represents annual take authorized through NMFS' SWFSC rulemaking/LOAs (80 FR 58982).
\4\ This value represents the calculated PBR less the average annual estimate of ongoing anthropogenic mortalities (i.e., total annual human-caused M/SI
column and the annual authorized take from the SWFSC column. In the case of California sea lion the M/SI column (318.4) and the annual authorized take
from the SWFSC (6.6) were subtracted from the calculated PBR.of 14,011. In the case of Short-beaked common dolphin the M/SI column (40) and the annual
authorized take from the SWFSC (2.8) were subtracted from the calculated PBR of 8,393.
\5\ See relevant SARs for more information regarding stock status and trends.
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 Tables 69 and 70, the following species or stocks
have potential or estimated (from ship strike and explosive takes,
respectively), and authorized, M/SI below their insignificance
threshold: fin whale (CA/OR/WA stock), gray whale (Eastern North
Pacific stock), humpback whale (Central North Pacific stock), sperm
whale (Hawaii stock), California sea lion (U.S stock), and short-beaked
common dolphin (CA/OR/WA stock). While the authorized mortality of
California sea lions (U.S. stock) are below the insignificance
threshold, because of the recent UMEs, we further address how the
authorized serious injury or mortality and the UME inform the
negligible impact determination immediately below. For the other five
stocks with authorized mortality 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 two stocks with
anticipated potential M/SI above the insignificance threshold, how that
M/SI compares to residual PBR, as well as additional factors, as
appropriate, are discussed below as well.
California Sea Lion (U.S. Stock)
The estimated (and authorized) lethal take of California sea lions
is well below the insignificance threshold (0.8 as compared to a
residual PBR of 13,686) and NMFS classifies the stock as ``increasing''
in the SARs. Nonetheless, we consider here how the 2013-present
California Sea Lion Unusual Mortality Event informs our negligible
impact determination. This UME was confined
[[Page 66990]]
to pup and yearling sea lions and many were emaciated, dehydrated, and
underweight. Although this UME has not been closed, NMFS staff
confirmed that the mortality of pups and yearlings returned to normal
in 2017 and 2018 and we plan to present it to the Working Group to
discuss closure by the end of 2018 (Deb Fauquier, pers. comm.). NMFS'
findings to date indicate that a change in the availability of sea lion
prey, especially sardines, a high value food source for nursing
mothers, was a likely contributor to the large number of strandings.
Sardine spawning grounds shifted further offshore in 2012 and 2013, and
while other prey were available (market squid and rockfish), these may
not have provided adequate nutrition in the milk of sea lion mothers
supporting pups, or for newly-weaned pups foraging on their own.
Although the pups showed signs of some viruses and infections, findings
indicate that this event was not caused by disease, but rather by the
lack of high quality, close-by food sources for nursing mothers.
Average mortalities from 2013-2017 averaged about 1,000-3,000 more
annually than they had in the previous 10 years. However, even if these
unusual mortalities were still occurring (with current data suggesting
they are not), 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. Further, the loss of
pups and yearlings would not be expected to have as much of an effect
on annual population rates as the death of adult females. In
conclusion, because of the abundance, population trend, and residual
PBR of this stock, as well as the fact that the increased mortality
stopped two years ago and the UME is expected to be closed soon, this
UME is not expected to have any impacts on individuals in the coming
five years, nor is it thought to have had impacts on the population
rate when it was occurring that would influence our evaluation of the
effects of authorized mortality on the stock.
Stocks With M/SI Above Residual PBR
Humpback Whale (CA/OR/WA Stock, Mexico DPS)
For this stock, PBR is currently set at 33.4 and the total annual
M/SI is estimated at greater than or equal to 40.76, yielding a
residual PBR of -7.36. NMFS is authorizing one serious injury or
mortality over the five-year duration of the rule (indicated as 0.2
annually for the purposes of comparing to PBR), which means that
residual PBR is exceeded by 7.56. However, as described previously, in
the commercial fisheries setting for ESA-listed marine mammals (which
is similar to 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 in
consideration). When those considerations are applied in the section
101(a)(5)(A) context, the authorized lethal take (0.2 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 serious injury and mortality
from activities other than those the Navy is conducting (summarized
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
authorized mortality is 0.2 (i.e., less than 1.45), which means that
the mortality authorized in this rule for HSTT activities will not
delay the time to recovery by more than 1 percent.
As described previously, 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 mortality and serious
injury to adversely affect the species or stock via impacts on annual
rates of recruitment or survival, which is discussed further below in
the stock-specific conclusion sections.
We discuss here the nature in which the predicted average annual
mortality from other sources has changed since the proposed rule. The
proposed rule included the information from the 2017 SAR, which
indicated that PBR was 11 and the total observed annual average
mortality was greater than or equal to 6.5 (one from vessel strikes and
>5.5 from fisheries interactions). The total human-caused mortality did
not exceed residual PBR, and our analysis, which considered other
factors as well, concluded that lethal take, alone, from the Navy's
activities would not have more than a negligible impact on humpback
whales (CA/OR/WA stock, Mexico DPS) (we also went on to analyze the
effects of the potential lethal take in conjunction with the estimated
harassment take under the negligible impact standard). In August 2018,
NMFS published draft 2018 SARs in which PBR increased to 33.4 and the
predicted average annual mortality increased to greater than or equal
to 40.76 (22 estimated from vessel collisions, >14.1 observed fisheries
interactions, and 2.16 predicted fisheries interactions if unidentified
entanglements are prorated based on a model based on known species
entanglements). While the observed mortality from vessel strikes
remains low at 2.1, the draft 2018 SAR relies 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, along with 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 vessel
strikes. The authors (Rockwood et al., 2017) do not suggest that ship
strike suddenly increased to 22 this year. In fact, the model is not
specific to a year, but rather offers a generalized prediction of ship
strike 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 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. We note that as of the date this final rule was
signed and transmitted to the Office of the Federal Register, the
public comment period for the draft 2018 SAR was still open. This means
that NMFS has not yet considered any comments that other experts and
the public might have regarding the propriety of the model for
identifying annual mortality in the SAR.
The CA/OR/WA stock of humpback whales experienced a steady increase
[[Page 66991]]
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 is not listed.
The mortality authorized by this rule is for an individual from the
Mexico DPS only. 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., 20111). 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, we also take into consideration management measures
in place to address serious injury and mortality caused by other
activities. The California swordfish and thresher shark drift gillnet
fishery is one of the primary causes of M/SI take from fisheries
interactions for humpback whales on the West Coast. NMFS established
the Pacific Offshore Cetacean Take Reduction Team in 1996 and prepared
an associated Plan (PCTRP) to reduce the risk of M/SI via fisheries
interactions. In 1997, NMFS published final regulations formalizing the
requirements of the PCTRP, including the use of pingers following
several specific provisions and the employment of Skipper education
workshops.
Crab pot fisheries are also a significant source of mortality for
humpback whales and, unfortunately, have increased mortalities over
recent years. However, the draft 2018 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, 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-entanglementworking-group/), referred to as the
Whale Entanglement Working Group. More recently, similar efforts to
address the entanglement issue have also been initiated in Oregon and
Washington. The Whale Entanglement Working Group has made significant
progress since 2015 and is tackling the problem from multiple angles,
including:
[ssquf] Development of Fact Sheets and Best Practices for
specific Fisheries issues (e.g., California Dungeness Crab Fishing
BMPs, or the 2018-2019 Best Fishing Practices Guide);
[ssquf] 2018-2019 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
[ssquf] 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. The April 2018 Working Group Report
reports on the progress of the RAMP (though there is a separate RAMP
report), summarized new ideas for Fisheries BMPs, and indicated next
steps.
We also note that on November 26, 2018, NMFS' West Coast Regional
Office received a notice of intent from the California Department of
Fish and Wildlife to apply for a Section 10 Incidental Take Permit
under the ESA to address protected species interactions in certain
California state-managed fixed gear fisheries. Any request for such a
permit must include a Habitat 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.
Further regarding measures in place to reduce mortality from
sources other than the Navy, the Channel Islands NMS staff coordinates,
collects, and monitors whale sightings in and around the Whale Advisory
Zone and the Channel Islands NMS region, which is within the area of
highest 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 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. Real time and historical whale observation data collected
from multiple sources can be viewed on the Point Blue Whale Database.
We also note that in this case, 0.2 M/SI annually means the
potential for one mortality in one of the five years and zero
mortalities in four of those five years. Therefore, the Navy would not
be contributing to the total human-caused mortality at all in four of
the five, or 80 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 four of the five years there could be no effect on annual
rates of recruitment or survival from Navy-caused M/SI. Additionally,
as noted previously, the loss of a male would have far less, if any, of
an effect on population rates and absent any information suggesting
that one sex is more likely to be struck than another, one could
reasonably assume that there is a 50 percent chance that the single
strike authorized by this rule would be a male, thereby further
decreasing the likelihood of impacts on the population
[[Page 66992]]
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 mortality or serious injury in four of the five years
and due to the fact that a single strike could be a male. 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. This is especially
important given the minor difference between zero and one across the
five-year period covered by this rule, which is the smallest
distinction possible when considering mortality. 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 stable, the potential (and authorized) mortality is well below
10 percent (0.6 percent) of PBR, and management actions are in place to
minimize both fisheries interactions and ship strike from other vessel
activity in the one of the highest-risk areas for strikes. More
specifically, although the total human-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 of five years and could
be comprised of a male (far less impactful to the population), the
potential impacts on population rates are even less. Based on the
presence of the factors described above, including consideration of the
fact that the authorized mortality of 0.2 will not delay the time to
recovery by more than 1 percent, we do not expect lethal take from Navy
activities, alone, 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 have a negligible
impact on the species and stock. Therefore this information will be
considered in combination with our assessment of the impacts of
harassment takes later in the section, in the humpback whale conclusion
section.
Blue Whale (Eastern North Pacific Stock)
For blue whales (Eastern North Pacific stock), PBR is currently set
at 2.3 and the total annual M/SI is estimated at greater than or equal
to 19, yielding a residual PBR of -16.7. NMFS is authorizing one
serious injury or mortality for the Navy over the five-year duration of
the rule (indicated as 0.2 annually for the purposes of comparing to
PBR), which means that residual PBR is exceeded by 16.9. However, as
described previously, in the commercial fisheries setting for ESA-
listed marine mammals (which is similar to the incidental take setting,
in that the negligible impact determination is based on the assessment
of take of 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 in consideration). When those
considerations are applied in the section 101(a)(5)(A) context, the
authorized lethal take (0.2 annually) of blue whales from the Eastern
North Pacific stock is less than 10 percent of PBR (which is 2.3) and
there are management measures in place to address serious injury and
mortality from activities other than those the Navy is conducting
(summarized below). Perhaps more importantly, the population is
considered ``stable'' and, specifically, the available data suggests
that the current number of ship strikes is not likely to have an
adverse impact on the population, despite the fact that it exceeds PBR,
with the Navy's minimal additional mortality of one whale in the five
years not creating the likelihood of adverse impact. Immediately below,
we explain the information that supports our finding that the Navy's
authorized mortality is not expected to result in more than a
negligible impact on this stock. As described previously, 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 mortality to adversely affect the species or stock via impacts on
annual rates of recruitment or survival, which occurs further below in
the stock-specific conclusion sections.
We discuss here the nature in which the predicted average annual
mortality from other sources has changed since the proposed rule. The
proposed rule included the information from the 2017 SAR, which
indicated that PBR was 2.3 and the total observed annual average
mortality (which was all from ship strike) was 0.9. There were no other
observed sources of mortality, the total human-caused mortality did not
exceed residual PBR, and our analysis, which considered other factors
as well, concluded that lethal take, alone, from the Navy's activities
would not have more than a negligible impact on blue whales (Eastern
North Pacific stock) (we also went on to analyze the effects of the
potential lethal take in conjunction with the estimated harassment take
under the negligible impact standard). In August 2018, NMFS published
draft 2018 SARs in which PBR remained at 2.3 and observed average
annual mortality went down to 0.2 (from ship strike). However, the
draft 2018 SAR relies 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,
along with 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 18 annual
mortalities of blue whales from vessel strikes, which, with the
additional M/SI of 0.96 from fisheries interactions, results in the
current estimate of residual PBR being -16.7. We note that as of the
date this final rule was signed and transmitted to the Office of
Federal Register, the public comment period for the draft 2018 SAR was
still open. This means that NMFS has not yet considered any comments
that other experts and the public might have regarding the propriety of
the model for identifying annual mortality in the SAR.
Although NMFS' Permits and Conservation Division in the Office of
Protected Resources has independently reviewed the new ship strike
model and its results and agrees that it is appropriate for estimating
blue whale mortality by ship strike on the U.S. West Coast, for
analytical purposes we also note that if the historical method were
used to predict vessel strike (i.e., using observed mortality by vessel
strike, or 0.2, instead of 18), then total human-caused mortality
including the Navy's potential take would not exceed PBR. We further
note that the authors (Rockwood et al., 2017) do not suggest that ship
strike suddenly increased to 18
[[Page 66993]]
this past year. In fact, the model is not specific to a year, but
rather offers a generalized prediction of ship strike 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 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 Eastern North Pacific stock
of blue whales remains stable nevertheless.
NMFS' draft 2018 SAR states that the stock is ``stable'' and there
is no indication of a population size increase in this blue whale
population since the early 1990s. The lack of a species' or stock's
population increase can have several causes, some of which are
positive. The draft SAR further cites to Monnahan et al. (2015), which
used a population dynamics model to estimate that the Eastern North
Pacific blue whale population was at 97 percent of carrying capacity in
2013 and to suggest that the observed lack of a population increase
since the early 1990s was explained by density dependence, not impacts
from ship strike. This would mean that this stock of blue whales shows
signs of stability and is not increasing in population size because the
population size is at or nearing carrying capacity for its available
habitat. And, in fact, we note that this stable population has
maintained this status throughout the years that Navy has consistently
tested and trained at similar levels (with similar vessel traffic) in
areas that overlap with blue whale occurrence.
Monnahan et al. (2015) modeled vessel numbers, ship strikes, and
the population of the Eastern North Pacific blue whale population from
1905 out to 2050 using a Bayesian framework to incorporate informative
biological information and assign probability distributions to
parameters and derived quantities of interest. The authors tested
multiple scenarios with differing assumptions, incorporated
uncertainty, and further tested the sensitivity of multiple variables.
Their results indicated that there is no immediate threat (i.e. through
2050) to the population from any of the scenarios tested, which
included models with 10 and 35 strike mortalities per year. Broadly,
the authors concluded that, unlike other blue whale stocks, the Eastern
North Pacific blue whales have recovered from 70 years of whaling and
are in no immediate threat from ship strikes. They further noted that
their conclusion conflicts with the depleted and strategic designation
under the MMPA, as well as PBR specifically.
As discussed, we also take into consideration management measures
in place to address serious injury and mortality caused by other
activities. The Channel Islands NMS staff coordinates, collects, and
monitors whale sightings in and around the Whale Advisory Zone and the
Channel Islands NMS region. Redfern et al. (2013) note that the most
risky area for blue whales is the Santa Barbara Channel, where shipping
lanes intersect with common feeding areas. 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 U.S.
Navy chartered aircraft. Information on seasonal presence, movement,
and general distribution patterns of large whales is shared with
mariners, NMFS Office of Protected Resources, U.S. Coast Guard,
California Department of Fish and Game, the Santa Barbara Museum of
Natural History, the Marine Exchange of Southern California, and whale
scientists. Real time and historical whale observation data collected
from multiple sources can be viewed on the Point Blue Whale Database.
We also note that in this case, 0.2 M/SI means one mortality in one
of the five years and zero mortalities in four of those five years.
Therefore, the Navy would not be contributing to the total human-caused
mortality at all in four of the five, or 80 percent, of the years
covered by this rule. That means that even if a blue whale were to be
struck, in four of the five years there could be no effect on annual
rates of recruitment or survival from Navy-caused M/SI. Additionally,
as noted previously, the loss of a male would have far less, if any, of
an effect on population rates and absent any information suggesting
that one sex is more likely to be struck than another, one could
reasonably assume that there is a 50 percent chance that the single
strike authorized by this rule would be a male, 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
mortality or serious injury in four of the five years and the fact that
the single strike could be a male. 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. This is especially important given the
minor difference between zero and one across the five-year period
covered by this rule, which is the smallest distinction possible when
considering mortality. 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 blue whale stock is stable, approaching carrying capacity, and has
leveled off because of density-dependence, not human-caused mortality,
in spite of what might be otherwise indicated from the calculated PBR.
Further, potential (and authorized) mortality is below 10 percent of
PBR and management actions are in place to minimize ship strike from
other vessel activity in the one of the highest-risk areas for strikes.
Based on the presence of the factors described above, we do not expect
lethal take from Navy activities, alone, to adversely Eastern North
Pacific blue whales through effects on 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 Eastern Central Pacific stock of blue whales from
the Navy's activities to ensure that the total authorized takes have a
negligible impact on the species or stock. Therefore, this information
will be considered in combination with our assessment of the impacts of
harassment takes later in the section.
Group and Species-Specific/Stock-Specific Analyses
The maximum amount and type of incidental take of marine mammals
reasonably likely to occur and therefore authorized from exposures to
sonar and other active acoustic sources and explosions during the five-
year training and testing period are shown in Tables 41 and 42 along
with the discussion in the Estimated Take of Marine Mammals section on
Vessel Strike and Explosives. The vast majority of predicted
[[Page 66994]]
exposures (greater than 99 percent) are expected to be Level B
harassment (non-injurious TTS and behavioral reactions) from acoustic
and explosive sources during training and testing activities at
relatively low received levels.
As noted previously, the estimated Level B harassment takes
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 many cases
some individuals are expected to be taken more than one time, while in
other cases a portion of individuals will not be taken at all. Below,
we compare the total take numbers (including PTS, TTS, and behavioral
harassment) for stocks to their associated abundance estimates to
evaluate the magnitude of impacts across the stock and to individuals.
Specifically, when an abundance percentage comparison is below 100, it
means that that percentage or less of the individuals in the stock will
be affected (i.e., some individuals will not be taken at all), that the
average for those taken is one day per year, and that we would not
expect any individuals to be taken more than a few times in a year.
When it is more than 100 percent, it means there will definitely be
some number of repeated takes of individuals. For 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. For some stocks these numbers have been adjusted
slightly (with these adjustments being in the single digits) since the
proposed rule so as to more consistently apply this approach, but these
minor changes did not change the analysis or findings.
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 behaviorally disturbed at the same time. As described in more
detail previously, 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
behaviorally harassed would result in impacts to reproduction or
survival. Alternately, we recognize that if an individual is
behaviorally harassed repeatedly for a longer duration and on
consecutive days, effects could accrue to the point that reproductive
success is jeopardized (as discussed below in the stock-specific
conclusions). Accordingly, as described in the previous paragraph, in
analyzing the number of takes and the likelihood of repeated and
sequential takes (which could accrue to reproductive impacts), we
consider the total takes, not just the behavioral harassment takes, so
that individuals exposed to both TS and behavioral harassment are
appropriately considered. We note that the same logic applies with the
potential addition of behavioral harassment to tissue damage from
explosives, the difference being that we do already consider the
likelihood of reproductive impacts whenever tissue damage occurs.
Further, the number of level A harassment takes by either PTS or tissue
damage are so low 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 mysticetes from sonar
and other active sound sources during testing and training activities
would be primarily from ASW events. It is important to note that
although ASW is one of the warfare areas of focus during MTEs, there
are significant periods when active ASW sonars are not in use.
Nevertheless, behavioral reactions are assumed more likely to be
significant during MTEs than during other ASW activities due to the
duration (i.e., multiple days) and scale (i.e., multiple sonar
platforms) of the MTEs. 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 responses, 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). When impacts to individuals
increase in 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 increases
substantially, especially if occurring 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, and death of males 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 those species or stocks where
it is possible for a small number of females to experience reproductive
effects, we explain below why there still will be no
[[Page 66995]]
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 and pinnipeds in water), 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 or stock. In
addition, animals belonging to each stock within a species typically
have the same hearing capabilities and behaviorally respond in the same
manner as animals in other stocks within the species. Thus, our
analysis below considers the effects of Navy's activities on each
affected stock even where discussion is organized by functional hearing
group and/or information is evaluated at the species level. Where there
are meaningful differences between stocks within a species that would
further differentiate the analysis (e.g., the status of the stock or
mitigation related to biologically important areas for the stock), 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 stocks will incur, the applicable mitigation for each stock,
and the status of the stocks to support the negligible impact
determinations for each stock. We have already described above why we
believe the incremental addition of the small number of low-level PTS
takes will not have any meaningful effect towards inhibiting
reproduction or survival. We have also described (above in this section
and in the proposed rule, respectively, with no new applicable
information received since publication of the proposed rule) the
unlikelihood of any masking or habitat impacts having effects that
would impact the reproduction or survival of any of the individual
marine mammals affected by the Navy's activities. For mysticetes, there
is no predicted tissue damage from explosives for any stock. Much of
the discussion below focuses on the behavioral effects and the
mitigation measures that reduce the probability or severity of effects
in biologically important areas. Because there are multiple stock-
specific factors in relation to the status of the species, as well as
mortality take for several stocks, at the end of the section we break
out our findings for most stocks on a stock-specific basis, however we
do consider five of the stocks in Hawaii with low-level impacts
together.
In Table 71 and Table 72 below, for mysticetes, we indicate the
total annual mortality, Level A and Level B harassment, and a number
indicating the instances of total take as a percentage of abundance.
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The majority of takes by harassment of mysticetes in the HSTT Study
Area are caused by sources from the MF1 active sonar 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 Table 1.5-5 in the Navy's
application). Most of the takes (62 percent) from the MF1 bin in the
HSTT Study Area would result from received levels between 154 and 172
dB SPL, while another 35 percent would result from exposure between 172
and 178 dB SPL. For the remaining active sonar bin types, the
percentages are as follows: LF3 = 96 percent between 142 and 160 dB
SPL, LF5 = 98 percent between 100 and 130 dB SPL, MF4 = 98 percent
between 136 and 154 dB SPL, MF5 = 97 percent between 118 and 142 dB
SPL, and HF4 = 98 percent between 100 and 148 dB SPL. These values may
be derived from the information in Tables 6.4-8 through 6.4-12 in the
Navy's rulemaking/LOA application (though they were provided directly
to NMFS upon request). For mysticetes, explosive training and testing
activities do not result in any Level B behavioral harassment, PTS from
explosives is fewer than 3 for every stock, and the TTS takes from
explosives comprise a small fraction (approximately 1-10 percent) of
those caused by exposure to active sonar. There are only two Level B
harassment takes of mysticetes by pile driving and airguns each, one
gray whale and one blue whale for each activity type. Based on this
information, the majority of the Level B behavioral harassment is
expected to be of low to sometimes moderate severity and of a
relatively shorter duration.
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 females with calves may be more responsive to stressors. As noted
in the Potential Effects of Specified Activities on Marine Mammals and
Their Habitat section, there are multiple examples from behavioral
response studies of odontocetes ceasing their feeding dives when
exposed to sonar pulses at certain levels, but alternately, blue whales
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 MFA sonar. Most Level B behavioral
harassment of mysticetes is likely to be short-term and low to moderate
severity, with no anticipated effect on reproduction or survival from
Level B harassment.
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
[[Page 66997]]
of travel, etc.). Oftentimes avoidance is temporary, and animals return
to the area once the noise has ceased. Some mysticetes may avoid larger
activities such as a MTE as it moves through an area, although these
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 the MTE
finishes. Due to the limited number and geographic scope of MTEs, it is
unlikely that most mysticetes would encounter a major training exercise
more than once per year and additionally, total hull-mounted sonar
hours are limited in several areas that are important to mysticetes
(described below). In the ocean, the use of 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 (due to 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), though we have
analyzed the impacts that are anticipated to occur and that we are
therefore authorizing.
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.
The Navy will also limit activities and employ other measures in
mitigation areas that will avoid or reduce impacts to mysticetes and
where BIAs for large whales have been identified in the HSTT Study
Area.
In the SOCAL portion of the HSTT Study Area, the Navy will
implement the San Diego Arc, San Nicolas Island, and Santa Monica/Long
Beach Mitigation Areas from June 1 through October 31, which will
reduce impacts primarily to blue whales, but also potentially gray
whales and fin whales. These mitigation areas fully overlap the three
associated blue whale Feeding Areas (all three of which are BIAs) in
the HSTT Study Area both temporally and spatially (see also the HSTT
FEIS/OEIS Appendix K (Geographic Mitigation Assessment), Section K.4);
only the Tanner-Cortes Bank BIA is not included for practicability
reasons discussed previously. Within these three Mitigation Areas, the
Navy will not exceed 200 hrs of MFAS sensor MF1 use (with the exception
of active sonar maintenance and systems checks) in all three of the
areas combined, annually, and will not use explosives during large-
caliber gunnery, torpedo, bombing, and missile (including 2.75-inch
(in) rockets) activities during training (or for mine warfare in the
San Nicolas and Santa Monica areas).
In addition, the Navy will implement the year-round Santa Barbara
Island Mitigation Area, which encompasses the portion of the Channel
Islands NMS that overlaps with the HSTT Study Area. The Navy will not
use MFAS sensor MF1 surface hull-mounted sonar or explosives used in
gunnery (all calibers), torpedo, bombing, and missile exercises
(including 2.75-in rockets) during training. This Mitigation area
overlaps a blue whale feeding BIA and also the Channel Islands NMS is
consider a highly productive and diverse area of high-value habitat
that is more typically free of anthropogenic stressors, and, therefore,
limiting activities in this area is considered habitat protection for
the myriad marine mammal species that use it or may pass through the
area.
In the HRC portion of the HSTT Study Area, the Navy will implement
the 4-Islands Region Mitigation Area, which is expected to reduce
impacts to humpback whales (during an important breeding/calving time
period), as well as the Main Hawaiian Island Insular stock of false
killer whale, monk seals, and several dolphin species. In this area,
the Navy will not use MFAS sensor MF1 during training or testing
activities from November 15 through April 15 nor will the Navy use any
explosives throughout the year that could potentially result in takes
of marine mammals. Since 2009, the Navy has adhered to a Humpback Whale
Cautionary Area as a mitigation area within the Hawaiian Islands
Humpback Whale NMS, an area identified as having one of the highest
concentrations of humpback whales, with calves, during the critical
winter months. As added protection, the Navy has expanded the size and
extended the season of the current Humpback Whale Cautionary Area,
renaming this area the 4-Islands Region Mitigation Area to reflect the
benefits afforded to multiple species. The season is currently between
December 15 and April 15 and the Navy has extended it from November 15
through April 15 for the purposes of this mitigation because the peak
humpback whale season has expanded. The size of the 4-Islands Region
Mitigation Area has also expanded since the last HSTT regulation to
include an area north of Maui and Molokai and overlaps an area
identified as a BIA for the endangered Main Hawaiian Islands insular
false killer whales (Baird et al., 2015; Van Parijs, 2015) (see Figure
5.4-3, in Chapter 5 Mitigation Areas for Marine Mammals in the Hawaii
Range Complex of the HSTT FEIS/OEIS).
Within the 4-Islands Region Mitigation Area is the Hawaiian Islands
Humpback Whale Reproduction Area BIA (4-Islands Region and Penguin
Bank). The use of sonar and other transducers primarily occur farther
offshore than the delineated boundaries of the Hawaiian Islands
Humpback Whale Reproduction Area BIA. Explosive events are typically
conducted in areas that are designated for explosive use, which are
areas outside of the Hawaiian Islands Humpback Whale Reproduction Area
BIA.
The restrictions on MFAS sensor MF1 in this area and the fact that
the Navy does not plan to use any explosives in this area mean that the
number of takes of humpback whales will be lessened, as will their
potential severity, in that the Navy is avoiding exposures in an area
and time where the takes would be more likely to interfere with cow/
calf communication or result in potentially heightened impacts on
sensitive or na[iuml]ve individuals (calves).
The Navy is also implementing the Hawaii Island Mitigation Area.
The Hawaii Island Mitigation Area is effective year-round and the Navy
will not use more than 300 hrs of MFAS sensory MF1 and will not exceed
20 hrs of MFAS sensory MF4. Also within the Hawaii Island Mitigation
Area, the Navy will not use any explosives (e.g., surface-to-surface or
air-to-surface
[[Page 66998]]
missile and gunnery events, BOMBEX, and mine neutralization) during
testing and training year-round. Of note here, this measure would
provide additional protection in this important reproductive area for
humpback whales, reducing impacts in an area and time where impacts
would likely be more severe if incurred. Separately (and addressed more
later), these protected areas also reduce impacts for identified
biologically important areas for endangered Main Hawaiian Islands
insular false killer whales, two species of beaked whales (Cuvier and
Blainville's), dwarf sperm whale, pygmy killer whale, melon-headed
whale, short-finned pilot whale, and several small resident populations
of dolphins (Baird et al., 2015; Van Parijs, 2015).
The 4-Islands Region Mitigation Area and the Hawaii Island
Mitigation Area both also overlap with portions (approximately 55
percent) of the Hawaiian Islands Humpback Whale NMS. The Navy will
continue to issue an annual humpback whale awareness notification
message to remind ships and aircraft to be extra vigilant during times
of high densities of humpback whales while in transit and to maintain
certain distances from animals during the operation of ships and
aircraft.
Below we compile and summarize the information that supports our
determination that the Navy's activities will not adversely impact
rates of recruitment or survival for any of the affected mysticete
stocks:
Blue Whale (Eastern North Pacific stock)--The SAR identifies this
stock as ``stable'' even though the larger species is listed as
endangered under the ESA. 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. As
discussed above, both the abundance and PBR are likely underestimated
to some degree in the SAR. NMFS will authorize one mortality over the
five years covered by this rule, or 0.2 mortality annually. With the
addition of this 0.2 annual mortality, residual PBR is exceeded,
resulting in the total human-caused mortality exceeding PBR by 16.9.
However, as described in more detail above in the Serious Injury and
Mortality subsection, when total human-caused mortality exceeds PBR, we
consider whether the incremental addition of a small amount of
authorized 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. In this case, the authorized mortality is well below 10
percent of PBR, management measures are in place to reduce mortality
from other sources, and the incremental addition of a single mortality
over the course of the five-year Navy rule is not expected to, alone,
lead to adverse impacts on the stock through effects on annual rates of
recruitment or survival.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance (measured against both the Navy-estimated
abundance and the SAR) is 253 and 121 percent, respectively (Table 72).
Given the range of blue whales, this information suggests that only
some portion of individuals in the stock are likely impacted, but that
there will likely be some repeat exposure (maybe 5 or 6 days within a
year) of some subset of individuals that spend extended time within the
SOCAL Range. Regarding the severity of those individual takes by Level
B behavioral harassment, 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
portion up to 178 dB (i.e., of a moderate or lower level, less likely
to evoke a severe response). Additionally, the Navy implements time/
area mitigation in SOCAL in the majority of the BIAs, which will reduce
the severity of impacts to blue whales by reducing interference in
feeding that could result in lost feeding opportunities or necessitate
additional energy expenditure to find other good opportunities.
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
would impact reproduction or survival. For similar reasons (described
above) the single estimated Level A harassment take by PTS for this
stock is unlikely to have any effect on the reproduction or survival of
that one individual, even if it were to be experienced by an animal
that also experiences one or more Level B harassment behavioral
disruptions.
Altogether, only a small portion of the stock is impacted and any
individual blue whale is likely to be disturbed at a low-moderate
level, with likely many animals exposed only once or twice and a subset
potentially disturbed across five or six days, but minimized in
biologically important areas. This low magnitude and 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 would not, alone, have more than a negligible impact on this
stock of blue whales), the total take 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 combined, that the
authorized take will have a negligible impact on the Eastern North
Pacific stock of blue whales.
Bryde's whale (Eastern Tropical Pacific stock)--Little is known
about this stock, or its status, and it is not listed under the ESA. No
mortality or Level A harassment is anticipated or authorized. Regarding
the magnitude of Level B harassment takes (TTS and behavioral
disruption), the number of estimated total instances of take compared
to the abundance is 3,154 percent, however, the abundance upon which
this percentage is based (1.3 whales from the Navy estimate, which is
extrapolated from density estimates based on very few sightings) is
clearly erroneous and the SAR does not include an abundance estimate
because all of the survey data is outdated (Table 72). However, the
abundance in the early 1980s was estimated as 22,000 to 24,000, a
portion of the stock was estimated at 13,000 in 1993, and the minimum
number in the Gulf of California was estimated at 160 in 1990. Given
this information and the fact that 41 total takes of Bryde's whales
were estimated, this information suggests that only a small portion of
the individuals in the stock are likely impacted, and few, if any, are
likely taken over more than one day. Regarding the severity of those
individual takes by Level B behavioral harassment, 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 portion up to 178 dB (i.e., of a moderate or lower
level, less likely to evoke a severe response). 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 Bryde's whale communication or other
important low-frequency cues. Any associated lost opportunities and
capabilities are not at a level that would impact reproduction or
survival.
Altogether, only a small portion of the stock is impacted and any
individual Bryde's whale is likely to be disturbed at a low-moderate
level, with few, if
[[Page 66999]]
any, individuals exposed over more than one day in the year. This low
magnitude and severity of harassment effects is not expected to result
in impacts on individual reproduction or survival, much less 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 Tropical Pacific stock of Bryde's whales.
Fin whale (CA/OR/WA stock)--The SAR identifies this stock as
``increasing,'' even though the larger species is listed as endangered
under the ESA. NMFS will authorize two mortalities over the five years
covered by this rule, or 0.4 mortality annually. The addition of this
0.4 annual mortality still leaves the total human-caused mortality well
under residual PBR.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance (measured against both the Navy-estimated
abundance and the SAR) is 613 and 25 percent, respectively (Table 72).
This information suggests that only some portion (less than 25 percent)
of individuals in the stock are likely impacted, but that there is
likely some repeat exposure (perhaps up to 12 days within a year) of
some subset of individuals that spend extended time within the SOCAL
complex. Some of these takes could occur on a few sequential days for
some small number of individuals, for example, if they resulted from a
multi-day exercise on a range while individuals were in the area for
multiple days feeding. Regarding the severity of those individual takes
by Level B behavioral harassment, 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 portion up to 178 dB (i.e., of a moderate or lower level, less
likely to evoke a severe response). Additionally, while there are no
designated BIAs for fin whales in the SOCAL range, the Navy implements
time/area mitigation in SOCAL in blue whale BIAs, and fin whales are
known to sometimes feed in some of the same areas, which means they
could potentially accrue some benefits from the mitigation. 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 fin whale communication or
other important low-frequency cues--and that the associated lost
opportunities and capabilities are not at a level that would impact
reproduction or survival. For similar reasons (described above) the
single estimated Level A harassment take by PTS for this stock is
unlikely to have any effects on the reproduction or survival of that
one individual.
Altogether, this population is increasing, only a small portion of
the stock is impacted, and any individual fin whale is likely to be
disturbed at a low-moderate level, with the taken individuals likely
exposed between one and twelve days, with a few individuals potentially
taken on a few sequential days. This low magnitude and 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 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 fin whales.
Humpback whale (CA/OR/WA stock)--The SAR identifies this stock as
stable (having shown a long-term increase from 1990 and then leveling
off between 2008 and 2014) and the individuals in this stock are
associated with three DPSs, one of which is not listed under the ESA
(Hawaii), one of which is designated as threatened (Mexico), and one of
which is designated as endangered (Central America) (individuals
encountered in the SOCAL portion of the HSTT Study Area are likely to
come from the latter two). NMFS will authorize one mortality over the
five years covered by this rule, or 0.2 mortality annually (Mexico DPS
only). With the addition of this 0.2 annual mortality, the total human-
caused mortality exceeds PBR by 7.56. However, as described in more
detail above in the Serious Injury and Mortality subsection, when total
human-caused mortality exceeds PBR, we consider whether the incremental
addition of a small amount of authorized 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 33.4.
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 Serious Injury and Mortality, the authorized mortality of 0.2
will not delay the time to recovery by more than 1 percent. Given these
factors, the incremental addition of a single mortality over the course
of the five-year Navy rule is not expected to, alone, lead to adverse
impacts on the stock through effects on annual rates of recruitment or
survival.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance (measured against both the Navy-estimated
abundance and the SAR) is 808 and 104 percent, respectively (Table 72).
Given the range of humpback whales, this information suggests that only
some portion of individuals in the stock are likely impacted, but that
there is likely some repeat exposure (maybe perhaps up to 16 days
within a year) of some subset of individuals that spend extended time
within the SOCAL complex. Regarding the severity of those individual
takes by Level B behavioral harassment, 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 portion up to 178 dB (i.e., of a moderate or lower level,
less likely to evoke a severe response). Some of these takes could
occur on several sequential days for some small number of individuals,
for example, if they resulted from a multi-day exercise on a range
while individuals were in the area for multiple days feeding, however,
in these amounts it would still not be expected to adversely impact
reproduction or survival of any individuals.
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 humpback whale
communication or other important low-frequency cues--and that the
associated lost opportunities and capabilities are not at a level that
would impact reproduction or survival. For similar reasons (described
above) the single estimated Level A harassment take by PTS for this
stock is unlikely to have any effects on the reproduction or survival
of that one individual.
Altogether, only a small portion of the stock is impacted and any
individual humpback whale is likely to be disturbed at a low-moderate
level, with likely many animals exposed only once or twice and a subset
potentially disturbed up to 16 days, but with no reason to think that
more than a few of those days would be sequential. This low magnitude
and severity of harassment effects is not expected to
[[Page 67000]]
result in impacts on the reproduction or survival of any individuals
and, therefore, when combined with the authorized mortality (which our
earlier analysis indicated would not, alone, have more than a
negligible impact on this stock of humpback whales), the total take 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 combined, that the authorized take will have a negligible
impact on the CA/OR/WA stock of humpback whales.
Minke whale (CA/OR/WA stock)--The status of this stock is unknown
and it is not listed under the ESA. No mortality from vessel strike or
tissue damage from explosive exposure is anticipated or authorized for
this species. Regarding the magnitude of Level B harassment takes (TTS
and behavioral disruption), the number of estimated total instances of
take compared to the abundance (measured against both the Navy-
estimated abundance and the SAR) is 568 and 146 percent, respectively
(Table 72). Based on the behaviors of minke whales, which often occur
along continental shelves and sometimes establish home ranges along the
West Coast, this information suggests that only a portion of
individuals in the stock are likely impacted, but that there is likely
some repeat exposure (perhaps up to 11 days within a year) of some
subset of individuals that spend extended time within the SOCAL
complex. Some of these takes could occur on a few sequential days for
some small number of individuals, for example, if they resulted from a
multi-day exercise on a range while individuals were in the area for
multiple days feeding. Regarding the severity of those individual takes
by Level B behavioral harassment, 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 portion up to 178 dB (i.e., of a moderate or lower level, less
likely to evoke a severe response). 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 minke whale communication or other important
low-frequency cues--and that the associated lost opportunities and
capabilities are not at a level that would impact reproduction or
survival. For similar reasons (described above) the single estimated
Level A harassment take by PTS for this stock is unlikely to have any
effects on the reproduction or survival of any individuals.
Altogether, only a portion of the stock is impacted and any
individual minke whale is likely to be disturbed at a low-moderate
level, with the taken individuals likely exposed between one and eleven
days, with a few individuals potentially taken on a few sequential
days. This low magnitude and severity of harassment effects is not
expected to result in impacts on individual reproduction or survival,
much less 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 minke whales.
Sei whale (Eastern North Pacific stock)--The status of this stock
is unknown and it is listed under the ESA. No mortality or Level A
harassment is anticipated or authorized. Regarding the magnitude of
Level B harassment takes (TTS and behavioral disruption), the number of
estimated total instances of take compared to the abundance (measured
against both the Navy-estimated abundance and the SAR) is 2,633 and 15
percent, respectively (Table 72), however, the abundance upon which the
Navy percentage is based (3 from the Navy estimate, which is
extrapolated from density estimates based on very few sightings) is
likely an underestimate of the number of individuals in the HSTT study
Area, resulting in an overestimated percentage. Nonetheless, even given
this information and the large range of sei whales, and the fact that
only 79 total Level B harassment takes of sei whales were estimated, it
is likely that some very small number of sei whales is taken
repeatedly, potentially up to 15 days in a year (typically 2,633
percent would lead to the estimate of 52 days/year, however, given that
there are only 79 sei whale total takes, we used the conservative
assumption that five individuals might be taken up to 15 times, with
the few remaining takes distributed among other individuals). Regarding
the severity of those individual takes by Level B behavioral
harassment, 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 portion up to 178
dB (i.e., of a moderate or lower level, less likely to evoke a severe
response). Some of these takes could occur on a few sequential days for
some small number of individuals, for example, if they resulted from a
multi-day exercise on a range while individuals were in the area for
multiple days feeding, however, in these amounts it would still not be
expected to adversely impact reproduction or survival of any
individuals. 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 sei
whale communication or other important low-frequency cues--and that the
associated lost opportunities and capabilities are not at a level that
would impact reproduction or survival.
Altogether, only a small portion of the stock is impacted and any
individual sei whale is likely to be disturbed at a low-moderate level,
with only a few individuals exposed over one to 15 days in a year, with
no more than a few sequential days. This low magnitude and severity of
harassment effects is not expected to result in impacts on individual
reproduction or survival, much less 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 species is not listed under the ESA.
NMFS will authorize two mortalities over the five years covered by this
rule, or 0.4 mortality annually. The addition of this 0.4 annual
mortality still leaves the total human-caused mortality well under the
insignificance threshold of residual PBR.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance (measured against both the Navy-estimated
abundance and the SAR) is 2,424 and 22 percent, respectively (Table
72). This information suggests that only some small portion of
individuals in the stock are likely impacted (less than 22 percent),
but that there is likely some level of repeat exposure of some subset
of individuals that spend extended time within the SOCAL complex.
Typically 2,424 percent would lead to the estimate of 48 days/year,
however, given that a large number of gray whales are known to migrate
through the SOCAL complex and the fact that there are only 4,678 total
takes, we believe that it is more likely that a large number of
individuals are taken one to a few times, while a small number staying
in an area to feed for several days may be taken on 5-10
[[Page 67001]]
days. Regarding the severity of those individual takes by Level B
behavioral harassment, 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
portion up to 178 dB (i.e., of a moderate or lower level, less likely
to evoke a severe response). Some of these takes could occur on a
couple of sequential days for some small number of individuals,
however, in these amounts it would still not be expected to adversely
impact reproduction or survival of any individuals.
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 gray whale
communication or other important low-frequency cues and that the
associated lost opportunities and capabilities are not at a level that
would 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,
at the expected scale the 7 estimated Level A harassment takes by PTS
for gray whales would be unlikely to impact behaviors, opportunities,
or detection capabilities to a degree that would interfere with
reproductive success or survival of any individuals.
Altogether, gray whales are not endangered or threatened under the
ESA and the Eastern North Pacific stock is increasing. Only a small
portion of the stock is impacted and any individual gray whale is
likely to be disturbed at a low-moderate level, with likely many
animals exposed only once or twice and a subset potentially disturbed
across five to ten days. This low magnitude and severity of harassment
effects is not expected to result in impacts to reproduction or
survival for any individuals and nor are these harassment takes
combined with the authorized mortality of two whales over the five 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.
Gray whale (Western North Pacific stock)--The Western North Pacific
stock of gray whales is considered ``increasing,'' but is listed as
endangered under the ESA. No mortality or Level A harassment is
anticipated or authorized. This stock is expected and authorized to
incur the very small number of 6 Level B harassment takes (2 behavioral
and 4 TTS) to a stock with a SAR-estimated abundance of 140. These
takes will likely accrue to different individuals, the behavioral
disturbances will be of a low-moderate level, and the TTS instances
will be at a low level and short duration. This low magnitude and
severity of harassment effects is not expected to result in impacts on
individual reproduction or survival, much less 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 Western North Pacific stock of
gray whales.
Humpback whale (Central North Pacific stock)--The SAR identifies
this stock as ``increasing'' and the DPS is not listed under the ESA.
No Level A harassment by tissue damage is authorized. NMFS will
authorize two mortalities over the five years covered by this rule, or
0.4 mortalities annually. The addition of this 0.4 annual mortality
still leaves the total human-caused mortality well under the
insignificance threshold for residual PBR.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated instances of take
compared to the abundance, both throughout the HSTT Study Area and
within the U.S. EEZ, respectively, is 180 and 161 percent (Table 71).
This information and the complicated far-ranging nature of the stock
structure suggests that some portion of the stock (but not all) are
likely impacted, over one to several days per year, with little
likelihood of take across sequential days. Regarding the severity of
those individual takes by Level B behavioral harassment, 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 portion up to 178 dB (i.e., of a
moderate or lower level, less likely to evoke a severe response).
Additionally, as noted above, there are two mitigation areas
implemented by the Navy that span a large area of this important
humpback reproductive area (BIA) and minimize impacts by limiting the
use of MF1 active sonar and explosives, thereby reducing both the
number and severity of takes of humpback whales. 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 humpback whale communication or other
important low-frequency cues, and that the associated lost
opportunities and capabilities are not at a level that would 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, at the
expected scale the 3 estimated Level A harassment takes by PTS for
humpback whales would be unlikely to impact behaviors, opportunities,
or detection capabilities to a degree that would interfere with
reproductive success or survival of any individuals.
Altogether, this stock is increasing and the DPS is not listed as
endangered or threatened under the ESA. Only a small portion of the
stock is impacted and any individual humpback whale is likely to be
disturbed at a low-moderate level, with the taken individuals likely
exposed between one and twelve days, with a few individuals potentially
taken on a few sequential days. This low magnitude and 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.
Blue whale (Central North Pacific stock) and the Hawaii stocks of
Bryde's whale, Fin whale, Minke whale, and Sei whale--The status of
these stocks are not identified in the SARs. Blue whale (Central North
Pacific stock) and the Hawaii stocks of fin whale and sei whale are
listed as endangered under the ESA; the Hawaii stocks of minke whales
and Bryde's whales are not listed under the ESA. No mortality or Level
A harassment by tissue damage is anticipated or authorized for any of
these stocks.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated instances of take
compared to the abundance, both throughout the HSTT Study Area and
within the U.S. EEZ, respectively, is 92-135 and 103-142
[[Page 67002]]
percent (Table 71). This information suggests that some portion of the
stocks (but not all) are likely impacted, over one to several days per
year, with little likelihood of take across sequential days. Regarding
the severity of those individual takes by Level B behavioral
harassment, 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 portion up to 178
dB (i.e., of a moderate or lower level, less likely to evoke a severe
response). 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 mysticete
communication or other important low-frequency cues--and that the
associated lost opportunities and capabilities are not at a level that
would impact reproduction or survival. For similar reasons (described
above) the two estimated Level A harassment takes by PTS for the Hawaii
stock of minke whales are unlikely to have any effects on the
reproduction or survival of any individuals.
Altogether, only a portion of these stocks are impacted and any
individuals of these stocks are likely to be disturbed at a low-
moderate level, with the taken individuals likely exposed between one
and several days, with little chance that any are taken across
sequential days. This low magnitude and severity of harassment effects
is not expected to result in impacts on individual reproduction or
survival, much less 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 these stocks.
Odontocetes
This section builds on the broader discussion above and brings
together the discussion of the different types and amounts of take that
different stocks will incur, the applicable mitigation for each stock,
and the status of the stocks to support the negligible impact
determinations for each stock. We have previously described (above in
this section and in the proposed rule, respectively, with no new
applicable information received since publication of the proposed rule)
the unlikelihood of any masking or habitat impacts having effects that
would impact the reproduction or survival of any of the individual
marine mammals affected by the Navy's activities. Here, we include
information that applies to all of the odontocete species and stocks,
which are then further divided and discussed in more detail in the
following subsections: Sperm whales, dwarf sperm whales, and pygmy
sperm whales; Dolphins and small whales; Beaked whales; and Dall's
porpoise. These sub-sections include more specific information about
the groups, as well as conclusions for each stock represented.
The majority of takes by harassment of odontocetes in the HSTT
Study Area are caused by sources from the MF1 active sonar bin (which
includes hull-mounted sonar) because they are high level, typically
narrowband sources at a frequency (in the 1-10 kHz range), which
overlap 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 Table 1.5-5 in the Navy's rulemaking/LOA application). For
odontocetes other than beaked whales (for which these percentages are
indicated separately in that section), most of the takes (98 percent)
from the MF1 bin in the HSTT Study Area would result from received
levels between 154 and 172 dB SPL. For the remaining active sonar bin
types, the percentages are as follows: LF3 = 97 percent between 142 and
160 dB SPL, LF5M = 99 percent between 106 and 118 dB SPL, MF4 = 99
percent between 136 and 160 dB SPL, MF5 = 97 percent between 118 and
148 dB SPL, and HF4 = 96 percent between 100 and 148 dB SPL. These
values may be derived from the information in Tables 6.4-8 through 6.4-
12 in the Navy's rulemaking/LOA application (though they were provided
directly to NMFS upon request). Based on this information, the majority
of the takes by Level B behavioral harassment 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 behavioral
harassment, TTS, or PTS if present) comprise a very small fraction (and
low number) of those caused by exposure to active sonar. Specifically,
for all but six odontocete stocks the instances of PTS and TTS from
explosives are five or fewer and 12 or fewer per stock, respectively.
By virtue of the sheer density and abundance of these two stocks, long-
beaked and short-beaked dolphins incur a slightly higher number--13 or
fewer and 30 or fewer instances of PTS and TTS, respectively. And,
because of the lower threshold for HF species, pygmy and dwarf sperm
whales have about 10-20 PTS takes and 30-100 TTS takes from explosives
per stock, while Dall's porpoises have about 50 PTS takes and 300 PTS
takes from explosives. Only five stocks incur take by harassment in the
form of TTS or PTS from exposure to air guns and in all five cases it
is limited to fewer than 10 takes each for TTS and PTS. No odontocetes
incur PTS from exposure to pile driving, and only two stocks incur TTS
in the amounts of one and three takes, respectively, from pile driving.
Because the majority of harassment take of odontocetes results from
the sources in the MF1 bin (typically a narrowband source in the 1-10
kHz range), the vast majority of threshold shift caused by Navy sonar
sources will typically occur across a narrower band in the range of 2-
20 kHz. This frequency range falls directly within the range of most
odontocete vocalizations. 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 shifts
that might be incurred by individuals exposed to explosives, pile
driving, or air guns 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 a few days of the year (with the exception of a few
stocks, which are explicitly discussed below), at the most, and
therefore they are unlikely to incur impacts on reproduction or
survival.
[[Page 67003]]
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).
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 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, 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), whereas
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.
Sperm Whales, Dwarf Sperm Whales, and Pygmy Sperm Whales
In this section, we bring together the discussion of marine mammals
generally and odontocetes in particular regarding the different types
and amounts of take that different stocks will incur, the applicable
mitigation for each stock, and the status of the stocks to support the
negligible impact determinations for each. We have also previously
described the unlikelihood of any masking or habitat impacts to any
marine mammals that would rise to the level of affecting individual
fitness. The discussion in this section fairly narrowly focuses
information that applies specifically to the sperm whale group, and
then because there are multiple stock-specific factors in relation to
differential Level B harassment effects and potential (and authorized)
mortality, we break out specific findings into a few groups--CA/OR/WA
stocks of sperm whales, dwarf sperm whales, and pygmy sperm whales;
sperm whale (Hawaii stock); and Pygmy and dwarf sperm whales (Hawaii
stocks).
In Table 73 and Table 74 below, for sperm whales, dwarf sperm
whales, and pygmy sperm whales, we indicate the total annual mortality,
Level A and Level B harassment, and a number indicating the instances
of total take as a percentage of abundance. No tissue damage is
anticipated.
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As discussed above, the majority of Level B harassment behavioral
takes of odontocetes, and thereby sperm whales, is expected to be in
the form of low to occasionally moderate severity 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 Level B
behavioral harassment is unlikely to cause long-term consequences for
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. However, impacts across higher numbers of days,
especially where sequential, have an increased probability of resulting
in energetic deficits that could accrue to effects on reproductive
success.
We note here that dwarf and pygmy sperm whales, as HF-sensitive
species, have a lower PTS threshold than all other groups and therefore
are likely to experience larger amounts of TTS and PTS, and NMFS will
accordingly authorize higher numbers. However, Kogia whales are still
likely to avoid sound levels that would cause higher levels of TTS
(greater than 20 dB) or PTS. Even though the number of TTS and PTS
takes are relatively high, all of the reasons described above for why
TTS and PTS are not expected to impact reproduction or survival still
apply.
We also note that impacts to dwarf sperm whale stocks will be
reduced through the Hawaii Island Mitigation Area, which overlaps (but
is larger than) the entirety of two BIAs for small resident populations
of dwarf and pygmy sperm whales. In this mitigation area, the Navy will
not conduct more than 300 hours of MF1 surface ship hull-mounted mid-
frequency active sonar or 20 hours of MF4 dipping sonar and will not
use explosives during testing and training.
Below we compile and summarize the information that supports our
determination that the Navy's activities will not adversely impact
recruitment or survival for any of the affected stocks addressed in
this section.
Sperm whale, dwarf sperm whale, and pygmy sperm whale (CA/OR/WA
stocks)--The SAR identifies the CA/OR/WA stock of sperm whales as
``stable'' and the species is listed as endangered under the ESA. The
status of the CA/OR/WA stocks of pygmy and dwarf sperm whales is
unknown and neither are listed under the ESA. Neither mortality nor
Level A harassment by tissue damage from exposure to explosives is
expected or authorized for any of these three stocks.
Due to their pelagic distribution, small size, and cryptic
behavior, pygmy sperm whales and dwarf sperm whales are rarely sighted
during at-sea surveys and difficult to distinguish between when
visually observed in the field. Many of the relatively few observations
of Kogia spp. off the U.S. West Coast were not identified to species.
All at-sea sightings of Kogia spp. have been identified as pygmy sperm
whales or Kogia spp. 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 spp. 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
abundance estimate it is not possible to predict the take of dwarf
sperm whales and take estimates are identified as Kogia spp. (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 density and
abundance in the U.S. EEZ is thought to be low.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance (measured against both the Navy-estimated
abundance and the SAR) is, respectively, 913 and 125 for sperm whales
and 1,211 and 223 for Kogia spp., with a large proportion of these
anticipated to be pygmy sperm whales due to the low abundance and
density of dwarf sperm whales in the HSTT Study Area. (Table 74). 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
suggests that some portion of the individuals in these stocks will not
be impacted, but that there is likely some repeat exposure (perhaps up
to 24 days within a year for Kogia spp. and 18 days a year for sperm
whales) of some small subset of individuals that spend extended time
within the SOCAL Range. 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
behavioral harassment, 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
[[Page 67005]]
lower, to occasionally moderate, level and less likely to evoke a
severe response). However, some of these takes could occur on a fair
number of sequential days for some number on individuals.
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 sperm whale
communication or other important low-frequency cues, and that the
associated lost opportunities and capabilities are not at a level that
would 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 Level A harassment
takes by PTS for the dwarf and pygmy whale stocks would be unlikely to
impact behaviors, opportunities, or detection capabilities to a degree
that would interfere with reproductive success or survival of any
individuals. Thus the 38 total Level A harassment takes by PTS for
these two stocks would be unlikely to affect rates of recruitment and
survival for the stocks.
Altogether, most members of the stocks will likely be taken by
Level B harassment (at a low to occasionally moderate level) over
several days a year, and some smaller portion of the stocks are
expected to be taken on a relatively moderate to high number of days
(up to 18 or 24) across the year, some of which could be sequential
days. Though the majority of impacts are expected to be of a lower to
sometimes moderate severity, the larger number of takes for a subset of
individuals makes it more likely that a 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. As noted previously,
however, foregone reproduction (especially for one year, which is the
maximum predicted because the small number anticipated in any one year
makes the probability that any individual would be impacted in this way
twice in five years very low) has far less of an impact on population
rates than mortality and a small number of instances of foregone
reproduction would not be expected to adversely affect these stocks
through effects on annual rates of recruitment or survival, and we note
that residual PBR is 19 for pygmy dwarf sperm whales and 1.6 for sperm
whales. Both the abundance and PBR are unknown for dwarf sperm whales,
however, we know that take of this stock is likely significantly lower
in magnitude and severity (i.e., lower number of total takes and
repeated takes any individual) than pygmy sperm whales. 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 the CA/OR/WA stocks of sperm whales and
pygmy and dwarf sperm whales.
Sperm whale (Hawaii stock)--The SAR does not identify a trend for
this stock and the species is listed as endangered under the ESA. No
Level A harassment by PTS or tissue damage is expected or authorized.
NMFS will authorize one mortality over the 5 years covered by this
rule, which is 0.2 mortalities annually. The addition of this 0.2
annual mortality still leaves the total human-caused mortality well
under the insignificance threshold for residual PBR.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated instances of take
compared to the abundance, both throughout the HSTT Study Area and
within the U.S. EEZ, respectively, is 151 and 147 percent (Table 73).
This information and the sperm whale stock range suggest that likely
only a smaller portion of the stock is impacted, over one to several
days per year, with little likelihood of take across sequential days.
Regarding the severity of those individual takes by Level B behavioral
harassment, 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, 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 sperm whale
communication or other important low-frequency cues, and that the
associated lost opportunities and capabilities are not at a level that
would impact reproduction or survival.
Altogether, a relatively small portion of this stock is impacted
and any individuals are likely to be disturbed at a low-moderate level,
with the taken individuals likely exposed between one and several days,
with little chance that any are taken across sequential days. This low
magnitude and severity of harassment effects is not expected to result
in impacts on individual reproduction or survival, nor are these
harassment takes combined with the single authorized mortality expected
to adversely affect the stock through 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 Hawaii stock of
sperm whales.
Pygmy and dwarf sperm whales (Hawaii stocks)--The SAR does not
identify a trend for these stocks and the species are not listed under
the ESA. No Level A harassment by tissue damage is authorized.
Regarding the magnitude of Level B harassment takes (TTS and behavioral
disruption), the number of estimated instances of take compared to the
abundance, both throughout the HSTT Study Area and within the U.S. EEZ,
respectively, is 244-249 and 235-240 percent (Table 73). This
information and the pygmy and dwarf sperm whale stock ranges (at least
throughout the U.S. EEZ around the entire Hawaiian Islands) suggest
that likely a fair portion of each stock is not impacted, but that a
subset of individuals may be over one to perhaps five days per year,
with little likelihood of take across sequential days. Regarding the
severity of those individual takes by Level B behavioral harassment, 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).
Additionally, as noted earlier, within the Hawaii Island Mitigation
Area, explosives are not used and the use of MF1 and MF4 active sonar
is limited, greatly reducing the severity of impacts within the small
resident population BIA for dwarf sperm whales, which is entirely
contained within this mitigation area.
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 sperm whale
communication or other important low-frequency cues--and that the
associated lost opportunities and capabilities are not at a level that
would impact reproduction or survival. For these same reasons (low
[[Page 67006]]
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,
at the expected scale, estimated Level A harassment takes by PTS for
dwarf and pygmy sperm whales would be unlikely to impact behaviors,
opportunities, or detection capabilities to a degree that would
interfere with reproductive success or survival of any individuals,
even if it were to be experienced by an animal that also experiences
one or more Level B harassment behavioral disruptions. Thus the 29 and
64 total Level A harassment takes by PTS for dwarf and pygmy sperm
whales, respectively, would be unlikely to affect rates of recruitment
and survival for these stocks.
Altogether, a portion of these stocks are likely to be impacted and
any individuals are likely to be disturbed at a low-moderate level,
with the taken individuals likely exposed between one and five days,
with little chance that any are taken across sequential days. This low
magnitude and severity of Level A and Level B harassment effects is not
expected to result in impacts on individual reproduction or survival,
much less 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 expected (and authorized) take
will have a negligible impact on the Hawaii stocks of pygmy and dwarf
sperm whales.
Beaked Whales
In this section, we build on the broader odontocete discussion
above (i.e., that information applies to beaked whales as well), except
where we offer alternative information about the received levels for
beaked whale Level B behavioral harassment. We bring together the
discussion of the different types and amounts of take that different
stocks will incur, the applicable mitigation for each stock, and the
status of the stocks to support the negligible impact determinations
for each stock. None of these species are listed as endangered or
threatened under the ESA. For beaked whales, there is no predicted
mortality or tissue damage for any stock. We have also described the
unlikelihood of any masking or habitat impacts to any groups that would
rise to the level of affecting individual fitness. The discussion below
focuses on additional information that is specific to beaked whales (in
addition to the general information on odontocetes provided above,
which is relevant to these species) to support the conclusions for each
stock. Because there are differential magnitudes of effect to the
Hawaii stocks of beaked whales versus the CA/OR/WA stocks of beaked
whales, we break out specific findings into those two groups.
In Tables 75 and 76 below, for beaked whales, we indicate the total
annual mortality, Level A and Level B harassment, and a number
indicating the instances of total take as a percentage of abundance. No
Level A harassment (PTS and Tissue Damage) takes are anticipated or
authorized.
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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 HSTT Study Area
are caused by sources from the MF1 active sonar bin (which includes
hull-mounted sonar) because they are high level narrowband sources in
the 1-10 kHz range, which overlap a more sensitive portion (though not
the most sensitive) of the MF hearing range, and of the sources
expected to result in take, they are used in a large portion of
exercises (see Table 1.5-5 in the Navy's rulemaking/LOA application).
Most of the takes (94 percent) from the MF1 bin in the HSTT Study Area
would result from received levels between 154 and 160 dB SPL. For the
remaining active sonar bin types, the percentages are as follows: LF3 =
90 percent between 136 and 148 dB SPL, LF5M = 99 percent between 100
and 118 dB SPL, MF4 = 95 percent between 130 and 148 dB SPL, MF5 = 95
percent between 100 and 142 dB SPL, and HF4 = 96 percent between 100
and 148 dB SPL. These values may be derived from the information in
Tables 6.4-8 through 6.4-12 in the Navy's rulemaking/LOA application
(though they were provided directly to NMFS upon request). 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.
As is the case with harbor porpoises, 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, i.e., 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, and no such
findings have been documented with Navy use in Hawaii and Southern
California.
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). 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. And 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). 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.
Cuvier's beaked whale responses suggested particular sensitivity to
sound exposure as consistent with results for Blainville's beaked
whale.
[[Page 67008]]
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
individual 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. Over
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 a natural beaked whale life
history functions (DiMarzio et al., 2018). Finally, results from
passive acoustic monitoring estimated regional Cuvier's beaked whale
densities were higher than indicated by the NMFS' broad scale visual
surveys for the U.S. west coast (Hildebrand and McDonald, 2009).
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 instances of take by
Level B behavioral harassment of a low to moderate severity are
unlikely to affect reproduction or survival. Here, some small number of
takes by Level B behavioral harassment could be in the form of a longer
(several hours or a day) and more moderate response, and/or some small
number could be repeated over more than several sequential days.
Impacts to reproduction could be possible for some small number of
individuals, but given the information presented regarding beaked whale
movement patterns, their return to areas within hours to a few days
after a disturbance, and their continued presence and abundance in the
area of instrumented Navy ranges, these impacts seem somewhat less
likely. Nonetheless, even where some smaller number of animals could
experience effects on reproduction, those responses would not be
expected to adversely affect rates of recruitment or survival.
We also note that impacts to beaked whale stocks will be reduced
through the Hawaii Island Mitigation Area, which overlaps (but is
larger than) almost the entirety of two BIAs for small resident
populations of Blainville's and Cuvier's beaked whales (the mitigation
area covers all of the BIA for Blainville's and all but a very small
portion of the BIA for Cuvier's). In this mitigation area, the Navy
will not conduct more than 300 hours of MF1 surface ship hull-mounted
mid-frequency active sonar and not more than 20 hours of MF4 dipping
sonar and will not use explosives during testing and training.
Below we synthesize and summarize the information that supports our
determination that the Navy's activities will not adversely impact
recruitment or survival rates for any of the affected stocks addressed
in this section:
Blainville's, Cuvier's, and Longman's beaked whales (Hawaii
stocks)--The SAR does not identify a trend for these stocks and the
species are not listed under the ESA. No mortality or Level A
harassment are expected or authorized for any of these three stocks.
Regarding the magnitude of Level B harassment takes (TTS and behavioral
disruption), the number of estimated instances of take compared to the
abundance, both throughout the HSTT Study Area and within the U.S. EEZ,
respectively, is 521-545 and 514-539 percent (Table 75). This
information and the stock ranges (at least of the small, resident
Island associated stocks around Hawaii) suggest that likely a fair
portion of the stocks (but not all) will be impacted, over one to
perhaps eleven days per year, with little likelihood of much take
across sequential days. Regarding the severity of those individual
takes by Level B behavioral harassment, 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
160 dB, though with beaked whales, which are considered somewhat more
sensitive, this could mean that some individuals will leave preferred
habitat for a day or two (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. Additionally, as noted earlier, within the
Hawaii Island mitigation area (which entirely contains the BIAs for
Cuvier's and Blainville's beaked whales), explosives are not used and
the use of MF1 and MF4 active sonar is limited, greatly reducing the
severity of impacts within these two small resident populations.
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 beaked whale
communication or other important low-frequency cues, and that the
associated lost opportunities and capabilities are not at a level that
would impact reproduction or survival.
Altogether, a fair portion of these stocks are impacted and any
individuals are likely to be disturbed at a moderate level, with the
taken individuals likely exposed between one and eleven days, with
little chance that individuals are taken across more than a few
sequential days. This low, to occasionally moderate, magnitude and
severity of harassment effects is not expected to result in impacts on
individual reproduction or survival, much less 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 Hawaii
stocks of beaked whales.
Baird's and Cuvier's beaked whales and Mesoplodon species (all CA/
OR/WA stocks)--The species are not listed under the ESA and their
populations have been identified as ``stable,'' ``decreasing,'' and
``increasing,'' respectively. No mortality or Level A harassment are
expected or authorized for any of these three stocks.
No methods are available to distinguish between the six species of
Mesoplodon beaked whale CA/OR/WA stocks (Blainville's beaked whale (M.
densirostris), Perrin's beaked whale (M. perrini), Lesser beaked whale
(M.
[[Page 67009]]
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 (Carretta et al., 2018). Bycatch
and stranding records from the region indicate that the Hubb's beaked
whale is 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 spp, and the six species 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 and take estimates are
identified as Mesoplodon spp.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance for these stocks is 2762, 2212, and 6960
percent (measured against Navy-estimated abundance) and 76, 351, and
203 percent (measured against the SAR) for Baird's beaked whales,
Cuvier's beaked whales, and Mesoplodon spp., respectively (Table 76).
Given the ranges of these stocks, this information suggests that some
smaller portion of the individuals of these stocks will be taken, and
that some subset of individuals within the stock will be taken
repeatedly within the year (perhaps up to 20-25 days)--potentially over
a fair number of sequential days, especially where individuals spend
extensive time in the SOCAL Range (note that we predicted lower days of
repeated exposure for these stocks than their percentages might have
suggested because of the lower overall number of takes). 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 behavioral harassment, 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 160 dB, though with beaked whales, which are
considered somewhat more sensitive, this could mean that some
individuals will leave preferred habitat for a day or two (i.e., of a
moderate level). However, as noted, some of these takes could occur on
a fair number of sequential days for these stocks.
As described previously, the severity of TTS takes, is expected to
be low-level, of short duration, and mostly not in a frequency band
that would be expected to interfere significantly with conspecific
communication, echolocation, or other important low-frequency cues.
Therefore, the associated lost opportunities and capabilities would not
be expected to impact reproduction or survival. For similar reasons
(described above) the single estimated Level A harassment take by PTS
for this stock is unlikely to have any effects on the reproduction or
survival of any individuals.
Altogether, a portion of these stocks will likely be taken (at a
moderate or sometimes low level) over several days a year, and some
smaller portion of the stock is expected to be taken on a relatively
moderate to high number of days across the year, some of which could be
sequential days. Though the majority of impacts are expected to be of a
moderate severity, the repeated takes over a potentially fair number of
sequential days for some individuals makes it more likely that a 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). As
noted previously, however, foregone reproduction (especially for only
one year in five, as discussed previously) has far less of an impact on
population rates than mortality and a small number of instances of
foregone reproduction would not be expected to adversely affect these
stocks through effects on annual rates of recruitment or survival,
especially given the residual PBR of these three beaked whale stocks
(16, 21, and 20, respectively).
Further, Navy activities have been conducted in SOCAL for many
years at similar levels and the SAR considers Mesoplodon spp. as
increasing and Baird's beaked whales as stable. While NMFS' SAR
indicates that Cuvier's beaked whales on the U.S. West Coast are
declining based on a Bayesian trend analysis of NMFS' survey data
collected from 1991 through 2014, results from passive acoustic
monitoring and other research have estimated regional Cuvier's beaked
whale densities that were higher than indicated by NMFS' broad-scale
visual surveys for the U.S. West Coast (Debich et al., 2015a; Debich et
al., 2015b; Falcone and Schorr, 2012, 2014; Hildebrand et al., 2009;
Moretti, 2016; [Scaron]irovi[cacute] et al., 2016; Smultea and
Jefferson, 2014). Research also indicates higher than expected
residency in the Navy's instrumented Southern California Anti-Submarine
Warfare Range in particular (Falcone and Schorr, 2012) and photo
identification studies in the SOCAL have identified approximately 100
individual Cuvier's beaked whale individuals with 40 percent having
been seen in one or more prior years, with re-sightings up to 7 years
apart (Falcone and Schorr, 2014). The documented residency by many
Cuvier's beaked whales over multiple years suggest that a stable
population may exist in that small portion of the stock's overall range
(Falcone et al., 2009; Falcone and Schorr, 2014; Schorr et al., 2017).
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 the CA/OR/WA stocks of Baird's and
Cuvier's beaked whales, as well as all six species included within the
Mesoplodon spp.
Small Whales and Dolphins
This section builds on the broader discussion above and compiles
the discussion of the different types and amounts of take that
different stocks will incur, the applicable mitigation for each stock,
and the status of the stocks to support the negligible impact
determinations for each stock. None of these species are listed as
endangered or threatened under the ESA. We also have described the
unlikelihood of any masking or habitat impacts to any groups that would
rise to the level of affecting individual fitness. The discussion below
focuses on additional information that is specific to the dolphin taxa
(in addition to the general information on odontocetes provided above,
which is relevant to these species) and to support the summarized
group-specific conclusions in the subsequent sections. Because of
several factors, we break out specific findings into three groups: 1)
long-beaked common dolphin (California stock), Northern right whale
dolphin, and short-beaked common dolphin (CA/OR/WA stocks), which all
have authorized mortality or tissue damage; 2) all other SOCAL dolphin
stocks except those identified in 1; and 3) all HRC dolphin stocks.
In Tables 77 and 78 below, for odontocetes (in this section
odontocetes refers specifically to the small whales and dolphins
indicated in Tables 77 and 78), we indicate the total annual
[[Page 67010]]
mortality, Level A and Level B harassment, and a number indicating the
instances of total take as a percentage of abundance.
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As described above, the large majority of Level B behavioral
harassments to odontocetes, and thereby dolphins and small whales, from
hull-mounted sonar (MF1) in the HSTT Study Area would result from
received levels between 160 and 172 dB SPL. Therefore, the majority of
Level B harassment takes 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.
Occasional milder occurrences of Level B behavioral harassment are
unlikely to cause long-term consequences for individual animals or
populations that have any effect on reproduction or survival. Some
behavioral responses could be in the form of a longer (several hours or
a day) and more moderate response, but because they are not expected to
be repeated over more than several sequential days at the most, impacts
to reproduction or survival for most animals are not anticipated. Even
where a few animals could experience effects on reproduction, for the
reasons explained below this would not affect rates of recruitment 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, common 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. Deep-diving dolphins 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.
Identified important areas for odontocetes (BIAs for small resident
populations) will be protected by the Navy's mitigation areas. The size
of the 4-Islands Region Mitigation Area has been expanded to include an
area north of Maui and Molokai and overlaps an area identified as a BIA
for the endangered Main Hawaiian Islands insular false killer whale
(Baird et al., 2015; Van Parijs, 2015) (see Figure 5.4-3, in Chapter 5
Mitigation Areas for Marine Mammals in the Hawaii Range Complex of the
HSTT FEIS/OEIS). The 4-Islands Region Mitigation Area provides partial
protection for identified biologically important areas that span
multiple islands for four species (small and resident populations)
including false killer whales, common bottlenose dolphin, pantropical
spotted dolphin, and spinner dolphin, by not using mid-frequency active
anti-submarine warfare sensor MF1 in the area during testing or
training.
The Navy's Hawaii Island Mitigation Area also provides additional
protection for identified biologically important areas (small and
resident populations) for multiple Main Hawaii Island species by not
conducting more than 300 hours of MF1 surface ship hull-mounted mid-
frequency active sonar or 20 hours of MF4 dipping sonar and not using
explosives during testing and training. Specifically, this Mitigation
Area entirely encompasses the BIAs for insular pygmy killer whales,
melon-headed whales, short-finned pilot whales, and the Hawaii
population of pantropical spotted dolphins; encompasses a large portion
of the rough-toothed dolphin BIA; and overlaps the Hawaii Island
portion of the multi-Island BIAs for false killer whales, common
bottlenose dolphin, and spinner dolphin.
Below we synthesize and summarize the information that supports our
[[Page 67012]]
determination that the Navy's activities will not adversely impact
recruitment or survival for any of the affected stocks addressed in
this section:
Long-beaked common dolphin (California stock), northern right whale
dolphin (CA/OR/WA stock), and short-beaked common dolphin (CA/OR/WA
stock)--None of these stocks is listed under the ESA and their stock
statuses are considered ``increasing,'' ``unknown,'' and ``stable,''
respectively. Short-beaked common dolphins are authorized for six takes
by mortality over the five-year rule, or 1.2 M/SI annually. The
addition of this 1.2 annual mortality still leaves the total human-
caused mortality well under the insignificance threshold for residual
PBR. The three stocks are expected and authorized to accrue 2, 1, and
10 Level A harassment takes from tissue damage resulting from exposure
to explosives, respectively. As described in greater detail previously,
the impacts of a Level A harassment take by tissue damage could range
in impact from minor to something just less than M/SI that could
seriously impact fitness. However, given the Navy's procedural
mitigation, exposure at the closer to the source and more severe end of
the spectrum is less likely and we cautiously assume some moderate
impact for these takes that could lower the affected individual's
fitness within the year such that a female (assuming a 50 percent
chance of it being a female) might forego reproduction for one year. As
noted previously, foregone reproduction has less of an impact on
population rates than death (especially for only one year in five), and
1 to 10 instances would not be expected to impact annual rates of
recruitment or survival for these stocks.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance (measured against both the Navy-estimated
abundance and the SAR) is 2411, 1273, and 571 (respective to the stocks
listed in the heading) and 244, 369, and 229 (respective to the stocks
listed in the heading) percent (Table 78). Given the range of these
stocks, this information suggests that likely some portion (but not all
or even the majority) of the individuals in the Northern right whale
dolphin and short-beaked common dolphin stocks are likely impacted,
while it is entirely possible that most or all of the range-limited
long-beaked common dolphin is taken. All three stocks likely will
experience some repeat Level B harassment exposure (perhaps up to 48,
25, or 11 days within a year, respective to the stocks listed in the
heading) of some subset of individuals that spend extended time within
the SOCAL range complex. 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 behavioral
harassment, 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 portion up to 178
dB (i.e., of a moderate or lower level, less likely to evoke a severe
response). However, some of these takes could occur on a fair number of
sequential days for long-beaked common dolphins or northern right whale
dolphins, or even some number of short-beaked common dolphins, given
the high number of total takes (i.e., the probability that some number
of individuals get taken on a higher number of sequential days is
higher, because the total take number is relatively high, even though
percentage not that high).
As described previously, the severity of TTS takes, is expected to
be low-level, of short duration, and mostly not in a frequency band
that would be expected to interfere significantly with conspecific
communication, echolocation, or other important low-frequency cues, and
the associated lost opportunities and capabilities would not be
expected to 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,
as discussed above, it would be unlikely to impact behaviors,
opportunities, or detection capabilities to a degree that would
interfere with reproductive success or survival of any individuals.
Altogether and as described in more detail immediately above,
short-beaked common dolphins are authorized for 1.2 annual lethal
takes, all three stocks may experience a very small number of takes by
tissue damage or PTS (relative to the stock abundance and PBR), and a
moderate to large portion of all three stocks will likely be taken (at
a low to occasionally moderate level) over several days a year, and
some smaller portion of these stocks is expected to be taken on a
relatively moderate to high number of days across the year, some of
which could be sequential days. Though the majority of impacts are
expected to be of a lower to sometimes moderate severity, the larger
number of takes (in total and for certain individuals) makes it more
likely (probabilistically) that a 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. As noted previously, however, foregone
reproduction (especially for only one year out of five) has far less of
an impact on population rates than mortality and a small number of
instances of foregone reproduction (including in combination with that
which might result from the small number of tissue damage takes) would
not be expected to adversely affect the stocks through effects on
annual rates of recruitment or survival, especially given the very high
residual PBRs of these stocks (621, 175, and 8353, respectively). For
these reasons, in consideration of all of the effects of the Navy's
activities combined (mortality, Level A harassment, and Level B
harassment), we have determined that the authorized take will have a
negligible impact on these three stocks of dolphins.
All other SOCAL dolphin stocks (except Long-beaked common dolphin,
Northern right whale dolphin, and short-beaked common dolphin)--None of
these stocks is listed under the ESA and their stock statuses are
considered ``unknown,'' except for the bottlenose dolphin (California
coastal stock) and killer whale (Eastern North Pacific stock), which
are considered ``stable.'' No M/SI or Level A harassment via tissue
damage from exposure to explosives is expected or authorized for these
stocks.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance (measured against both the Navy-estimated
abundance and the SAR) is from 440-2675 and 45 to 2881, respectively
(Table 78). Given the range of these stocks (along the entire U.S. West
Coast, or even beyond, with some also extending seaward of the HSTT
Study Area boundaries), this information suggests that some portion
(but not all or even the majority) of the individuals of any of these
stocks will be taken, with the exception that most or all of the
individuals of the more
[[Page 67013]]
range-limited California coastal stock of bottlenose dolphin may be
taken. It is also likely that some subset of individuals within most of
these stocks will be taken repeatedly within the year (perhaps up to
10-15 days within a year), but with no more than several potentially
sequential days, although the CA/OR/WA stocks of bottlenose dolphins,
Pacific white-sided dolphins, and Risso's dolphins may include
individuals that are taken repeatedly within the year over a higher
number of days (up to 57, 22, and 40 days, respectively) and
potentially over a fair number of sequential days, especially where
individuals spend extensive time in the SOCAL range complex. Note that
though percentages are high for the Eastern North Pacific stock of
killer whales and short-finned pilot whales, given the low overall
number of takes, it is highly unlikely that any individuals would be
taken across the number of days their percentages would suggest. 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 behavioral harassment, 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, or sometimes moderate
level, less likely to evoke a severe response). However, as noted, some
of these takes could occur on a fair number of sequential days for the
three stocks listed earlier.
As described previously, regarding the severity of TTS takes, is
expected to be low-level, of short duration, and mostly not in a
frequency band that would be expected to interfere significantly with
conspecific communication, echolocation, or other important low-
frequency cues. 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, it would be unlikely to
impact behaviors, opportunities, or detection capabilities to a degree
that would interfere with reproductive success or survival of any
individuals.
Altogether, a portion of all of these stocks will likely be taken
(at a low to occasionally moderate level) over several days a year, and
some smaller portion of CA/OR/WA stocks of bottlenose dolphins, Pacific
white-sided dolphins, and Risso's dolphins, specifically, are expected
to be taken on a relatively moderate to high number of days across the
year, some of which could be sequential days. Though the majority of
impacts are expected to be of a lower to sometimes moderate severity,
the larger number of takes (in total and for certain individuals) for
the CA/OR/WA stocks of bottlenose dolphins, Pacific white-sided
dolphins, and Risso's dolphins makes it more likely (probabilistically)
that a 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. As noted previously, however, foregone reproduction (especially
for only one year in five) has far less of an impact on population
rates than mortality and a small number of instances of foregone
reproduction would not be expected to adversely affect the stocks
through effects on annual rates of recruitment or survival, especially
given the residual PBRs of the CA/OR/WA stocks of bottlenose dolphins,
Pacific white-sided dolphins, and Risso's dolphins (9.4, 183, and 84,
respectively). 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 these stocks of
dolphins.
All HRC dolphin stocks--With the exception of the Main Hawaiian
Island stock of false killer whales (listed as endangered under the
ESA, with the MMPA stock identified as ``decreasing''), none of these
stocks are listed under the ESA and their stock statuses are considered
``unknown.'' No M/SI or Level A harassment via tissue damage from
exposure to explosives is expected or authorized for these stocks.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance (measured against both the Navy-estimated
abundance and the SAR) is from 46-1169 percent and 41 to 2130 percent,
respectively (Table 77). Given the ranges of these stocks (many of them
are small, resident, island-associated stocks), this information
suggests that a fairly large portion of the individuals of many of
these stocks will be taken, but that most individuals will only be
impacted across a smaller to moderate number of days within the year
(1-15), and with no more than several potentially sequential days,
although two stocks (the Oahu stocks of bottlenose dolphin and
pantropical spotted dolphin) have a slightly higher percentage,
suggesting they could be taken up to 23 days within a year, with
perhaps a few more of those days being sequential. We note that
although the percentage is higher for the tropical stock of pygmy
killer whale within the U.S. EEZ (2130), given (1) the low overall
number of takes (760) and (2) the fact that the small within-U.S. EEZ
abundance is not a static set of individuals, but rather individuals
moving in and out of the U.S. EEZ making it more appropriate to use the
percentage comparison for the total takes versus total abundance--it is
highly unlikely that any individuals would be taken across the number
of days the within-U.S. EEZ percentage suggests (42). 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 behavioral harassment, 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, or sometimes moderate level, less likely to evoke a
severe response). However, as noted, some of these takes could occur on
a fair number of sequential days for the Oahu stocks of bottlenose
dolphin and pantropical spotted dolphins.
Regarding the severity of TTS takes, as described previously they
are expected to be low-level, of short duration, and mostly not in a
frequency band that would be expected to interfere significantly with
conspecific communication, echolocation, or other important low-
frequency cues. 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, they would be unlikely to
impact behaviors, opportunities, or detection capabilities to a degree
that would interfere with reproductive success or survival of any
individuals, even if accrued to individuals that are also taken by
behavioral harassment at the same time.
Altogether, most of these stocks (all but the Oahu stocks of
bottlenose dolphin and pantropical spotted
[[Page 67014]]
dolphins) will likely be taken (at a low to occasionally moderate
level) over several days a year, with some smaller portion of the stock
potentially taken on a more moderate number of days across the year
(perhaps up to 15 days for Fraser's dolphin, though others notably
less), some of which could be across a few sequential days, which is
not expected to affect the reproductive success or survival of
individuals. For the Oahu stocks of bottlenose dolphin and pantropical
spotted dolphins, some subset of individuals could be taken up to 23
days in a year, with some small number being taken across several
sequential days, such that a 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. As noted previously, however, foregone
reproduction (especially for one year, which is the maximum predicted
because the small number anticipated in any one year makes the
probability that any individual would be impacted in this way twice in
five years very low) has far less of an impact on population rates than
mortality and a small number of instances of foregone reproduction
would not be expected to adversely affect these two stocks through
effects on annual rates of recruitment or survival.
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 of the stocks of dolphins found in
the vicinity of the HRC (Table 77).
Dall's Porpoise
In this section, we build on the broader odontocete discussion
above (i.e., that information applies to Dall's porpoises as well),
except where we offer alternative information about the received levels
for Dall's porpoise Level B behavioral harassment. We discuss the
different types and amounts of take that the stock will incur, the
applicable mitigation for the stock, and the status of the stock to
support the negligible impact determination. The discussion below
focuses on additional information that is specific to porpoises (in
addition to the general information on odontocetes provided above,
which is relevant to this species) to support the conclusion for this
stock. We have described previously (above in this section and in the
proposed rule, respectively, with no new applicable information
received since publication of the proposed rule) the unlikelihood of
any masking or habitat impacts to Dall's porpoises that would affect
reproduction or survival.
In Table 79 below, for Dall's porpoise, we indicate the total
annual mortality, Level A and Level B harassment, and a number
indicating the instances of total take as a percentage of abundance.
[GRAPHIC] [TIFF OMITTED] TR27DE18.038
Most Level B harassments to Dall's porpoise from hull-mounted sonar
(MF1) in the HSTT Study Area would result from received levels between
154 and 166 dB SPL (85 percent). 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 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. Therefore,
the majority of Level B takes are 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.
Dall's porpoise is not listed under the ESA and the stock status is
considered ``unknown.'' No M/SI or Level A harassment via tissue damage
from exposure to explosives is expected or authorized for this stock.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), the number of estimated total instances of take
compared to the abundance (measured against both the Navy-estimated
abundance and the SAR) is 2170 and 173, respectively (Table 79). Given
the range of this stock (up the U.S. West Coast through Washington and
sometimes beyond the U.S. EEZ), this information suggests that some
smaller portion of the individuals of these stocks will be taken, and
that
[[Page 67015]]
some subset of individuals within the stock will be taken repeatedly
within the year (perhaps up to 42 days)--potentially over a fair number
of sequential days, especially where individuals spend extensive time
in the SOCAL range complex. 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 behavioral
harassment, 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, or
sometimes moderate level, less likely to evoke a severe response).
However, as noted, some of these takes could occur on a fair number of
sequential days for this stock.
As described previously, the severity of TTS takes, is expected to
be low-level, of short duration, and mostly not in a frequency band
that would be expected to interfere significantly with conspecific
communication, echolocation, or other important low-frequency cues.
Therefore, the associated lost opportunities and capabilities would not
be expected to impact reproduction or survival. For these same reasons
(low level and the likely 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 estimated 209 Level A harassment takes by PTS for
Dall's porpoise would be unlikely to impact behaviors, opportunities,
or detection capabilities to a degree that would interfere with
reproductive success or survival for most individuals. Because of the
high number of PTS takes, however, we acknowledge that a few animals
could potentially incur permanent hearing loss of a higher degree that
could potentially interfere with their successful reproduction and
growth. Given the status of the stock, even if this occurred, it would
not adversely impact rates of recruitment or survival.
Altogether, a portion of this stock will likely be taken (at a low
to occasionally moderate level) over several days a year, and some
smaller portion of the stock is expected to be taken on a relatively
moderate to high number of days across the year, some of which could be
sequential days. Though the majority of impacts are expected to be of a
lower to sometimes moderate severity, the larger number of takes (in
total and for certain individuals) for the Dall's porpoise makes it
more likely (probabilistically) that a 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. Similarly, we acknowledge
the potential for this to occur to a few individuals out of the 209
total that might incur a higher degree of PTS. As noted previously,
however, foregone reproduction (especially for only one year in five)
has far less of an impact on population rates than mortality. Further,
the small number of instances of foregone reproduction that could
potentially result from PTS and/or the few repeated, more severe
behavioral harassment takes would not be expected to adversely affect
the stock through effects on annual rates of recruitment or survival,
especially given the status of the species (not endangered or
threatened; minimum population of 25,170 just within the U.S. EEZ) and
residual PBR of Dall's porpoise (171.4). 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 Dall's porpoise.
Pinnipeds
In this section, we build on the broader discussion above and bring
together the discussion of the different types and amounts of take that
different species and stocks will incur, the applicable mitigation for
each stock, and the status of the stocks to support the negligible
impact determinations for each stock. Of these stocks, only Hawaiian
monk seals and Guadalupe fur seals are listed under the ESA (endangered
and threatened, respectively) and the SARs identify both stocks as
``increasing.'' The other stocks are not ESA-listed. All of the
pinniped stocks are considered ``increasing,'' except for harbor seal
(California stock), which is considered stable, and Hawaiian monk
seals, which are increasing in the main Hawaiian islands, but
decreasing in the Northwest Hawaiian islands (the SAR says that
therefore they are not certain whether to consider the whole stock as
decreasing, stable, or possible increasing). Broadly, we have already
described above why we believe the incremental addition of the
comparatively small number of low-level PTS takes in predominantly
narrow frequency bands will not have any meaningful effect towards
inhibiting reproduction or survival. Other than for California sea
lions, no mortality is expected or authorized. We have described (above
in this section and in the proposed rule, respectively, with no new
applicable information received since publication of the proposed rule)
the unlikelihood of any masking or habitat impacts to any groups that
would rise to the level of affecting reproduction or survival.
In Tables 80 and 81 below, for pinnipeds, we indicate the total
annual mortality, Level A and Level B harassment, and a number
indicating the instances of total take as a percentage of abundance.
BILLING CODE 3510-22-P
[[Page 67016]]
[GRAPHIC] [TIFF OMITTED] TR27DE18.039
[GRAPHIC] [TIFF OMITTED] TR27DE18.040
BILLING CODE 3510-22-C
The majority of takes by harassment of pinnipeds in the HSTT Study
Area are caused by sources from the MF1 active sonar 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 Table 1.5-5 in the
Navy's rulemaking/LOA application). Most of the takes (83 percent) from
the MF1 bin in the HSTT Study Area would result from received levels
between 160 and 172 dB SPL, while another 16 percent would result from
exposure between 172 and 178 dB SPL. For the remaining active sonar bin
types, the percentages are as follows: LF3 = 92 percent between 154 and
166 dB SPL, LF5M = 99 percent between 112 and 124 dB SPL, MF4 = 98
percent between 148 and 166 dB SPL, MF5 = 97 percent between 130 and
160 dB SPL, and HF4 = 96 percent between 100 and 160 dB SPL. These
values may be derived from the information in Tables 6.4-8 through 6.4-
12 in the Navy's rulemaking/LOA application (though they were provided
directly to NMFS upon request). Exposures at these levels would be
considered of low to occasionally moderate severity. 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 behavioral harassment are unlikely to cause long-term
consequences for individual animals or populations, especially when
they are not expected to be repeated over sequential multiple days. For
all pinnipeds, harassment takes from explosives (behavioral, TTS, or
PTS if present) comprise a very small fraction of those caused by
exposure to active sonar. No PTS is expected to result from pile
driving or air guns for pinnipeds and TTS from pile driving and air
guns is limited to single digits for elephant seals.
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 incurred by
pinnipeds would typically only interfere with communication within a
portion of a pinniped's range (if it occurred during a time when
communication with conspecifics was
[[Page 67017]]
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 or air guns 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.
We note that as described previously, the Hawaii and 4-Islands
mitigation areas protect (by not using explosives and limiting MFAS
within) a significant portion of the designated critical habitat for
Hawaiian monk seals in the Main Hawaiian Islands, including all of it
around the islands of Hawaii and Lanai, most around Maui, and good
portions around Molokai and Kaho'olawe. As discussed, this protection
reduces the overall number of takes, and further reduces the severity
of effects by minimizing impacts near pupping beaches and in important
foraging habitat.
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 HSTT 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, which would have no effect on
reproduction or survival. 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 hearing impairment or to
significantly disrupt foraging behavior.
Thus, even repeated Level B harassment of some small 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 adverse impact on rates of recruitment or survival
for the stock as a whole.
The Navy is authorized for four M/SI takes of California sea lions
and when this mortality is combined with the other human-caused
mortality from other sources, it still falls well below the
insignificance threshold for residual PBR. A small number of Level A
harassment takes by tissue damage will also be authorized (9 and 2 for
California sea lions and northern elephant seals, respectively), which,
as noted previously, could range in impact from minor to something just
less than M/SI that could seriously impact fitness. However, given the
Navy's mitigation, exposure at the closer to the source and more severe
end of the spectrum is less likely. Nevertheless, we cautiously assume
some moderate impact on the individuals that experience these small
numbers of take that could lower the individual's fitness within the
year such that a female (assuming a 50 percent chance of it being a
female) might forego reproduction for one year. As noted previously,
foregone reproduction has less of an impact on population rates than
death (especially for only one within five years) and these low numbers
of instances (especially assuming the likelihood that only 50 percent
of the takes would affect females) would not be expected to impact
annual rates of recruitment or survival, especially given the
population sizes of these species.
Regarding the magnitude of Level B harassment takes (TTS and
behavioral disruption), for Hawaiian monk seals and Guadalupe fur
seals, the two species listed under the ESA, the estimated instances of
takes as compared to the stock abundance does not exceed 124 percent,
which suggests that some portion of these two stocks would be taken on
one to a few days per year. For the remaining stocks, the number of
estimated total instances of take compared to the abundance (measured
against both the Navy-estimated abundance and the SAR) for these stocks
is 1,484-2,896 percent and 18-40 percent, respectively (Table 81).
Given the ranges of these stocks (i.e., very large ranges, but with
individuals often staying in the vicinity of haulouts), this
information suggests that some very small portion of the individuals of
these stocks will be taken, but that some subset of individuals within
the stock will be taken repeatedly within the year (perhaps up to 58
days)--potentially over a fair number of sequential days. Regarding the
severity of those individual takes by Level B behavioral harassment, 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, which is considered a relatively low
to occasionally moderate level for pinnipeds. However, as noted, some
of these takes could occur on a fair number of sequential days for this
stock.
As described previously, the severity of TTS takes, expected to be
low-level, of short duration, and mostly not in a frequency band that
would be expected to interfere significantly with conspecific
communication, echolocation, or other important low-frequency cues that
would affect the individual's 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
[[Page 67018]]
some small loss of opportunities or detection capabilities, the one to
eight estimated Level A harassment takes by PTS for monk seals,
northern fur seals, and harbor seals would be unlikely to impact
behaviors, opportunities, or detection capabilities to a degree that
would interfere with reproductive success or survival of any
individuals. Because of the high number of PTS takes for California sea
lions and northern elephant seals (87 and 97, respectively); however,
we acknowledge that a few animals could potentially incur permanent
hearing loss of a higher degree that could potentially interfere with
their successful reproduction and growth. Given the status of the
stock, even if this occurred, it would not adversely impact rates of
recruitment or survival (residual PBR of 13,686 and 4,873,
respectively).
Altogether, Hawaiian monk seals and Guadalupe fur seals individuals
will be taken no more than a few days in any year, with none of the
expected take anticipated to affect individual reproduction or
survival, let alone annual rates of recruitment and survival. With all
other stocks, only a very small portion of the stock will be taken in
any manner. Of those taken, some individuals will be taken by Level B
harassment (at a moderate or sometimes low level) over several days a
year, and some smaller portion of those taken will be on a relatively
moderate to high number of days across the year (up to 58), a fair
number of which would likely be sequential days. Though the majority of
impacts are expected to be of a lower to sometimes moderate severity,
the repeated takes over a potentially fair number of sequential days
for some individuals makes it more likely that some 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). As noted
previously, however, foregone reproduction (especially for only one
year within five) has far less of an impact on population rates than
mortality and a relatively small number of instances of foregone
reproduction (as compared to the stock abundance and residual PBR)
would not be expected to adversely affect the stock through effects on
annual rates of recruitment or survival, especially given the status of
these stocks. Accordingly, we do not anticipate the relatively small
number of individual Northern fur seals or 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 stocks
through effects on rates of recruitment or survival, given the status
of the stocks, which are respectively increasing and stable with
abundances and residual PBRs of 14,050/30,968 and 449/1,598.
For California sea lions, given the very high abundance and
residual PBR (296,750 and 13,686), as well as the increasing status of
the stock in the presence of similar levels of Navy activities over
past years--the impacts of 0.2 annual mortalities, potential foregone
reproduction for up to nine individuals in a year taken by tissue
damage and some relatively small number of individuals taken as a
result of repeated behavioral harassment over a fair number of
sequential days are not expected to adversely affect the stock through
effects on annual rates of recruitment or survival. similarly, for
Northern elephant seals, given the very high abundance and residual PBR
(179,000 and 4,873), as well as the increasing status of the stock in
the presence of similar levels of Navy activities over past years--the
impacts of potential foregone reproduction for up to two individuals in
a year taken by tissue damage and some relatively small number of
individuals taken as a result of repeated behavioral harassment over a
fair number of sequential days are not expected to adversely affect the
stock through effects on annual rates of recruitment or survival. For
these reasons, in consideration of all of the effects of the Navy's
activities combined (mortality, Level A harassment, and Level B
harassment), we have determined that the authorized take will have a
negligible impact on all pinniped species and stocks (Tables 80 and
81).
Determination
Based on the analysis contained herein of the likely effects of the
specified activities 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 and stocks.
Subsistence Harvest of Marine Mammals
There are no relevant subsistence uses or harvest of marine mammals
implicated by this action. Therefore, NMFS has determined that the
total taking affecting species or stocks would not have an unmitigable
adverse impact on the availability of such species or stocks for taking
for subsistence purposes.
Endangered Species Act
There are nine marine mammal species under NMFS jurisdiction that
are listed as endangered or threatened under the ESA with confirmed or
possible occurrence in the HSTT Study Area: Blue whale (Eastern and
Central North Pacific stocks), fin whale (CA/OR/WA and Hawaii stocks),
gray whale (Western North Pacific stock), humpback whale (Mexico and
Central America DPSs), sei whale (Eastern North Pacific and Hawaii
stocks), sperm whale (CA/OR/WA and Hawaii stocks), false killer whale
(Main Hawaii Islands Insular), Hawaiian monk seal (Hawaii stock), and
Guadalupe fur seal (Mexico to California). There is also ESA-designated
critical habitat for Hawaiian monk seals and Main Hawaiian Island
insular false killer whales. The Navy consulted with NMFS pursuant to
section 7 of the ESA, and NMFS also consulted internally on the
issuance of these regulations and LOAs under section 101(a)(5)(A) of
the MMPA for HSTT activities. NMFS issued a Biological Opinion
concluding that the issuance of the rule and subsequent LOAs is not
likely to jeopardize the continued existence of the threatened and
endangered species under NMFS' jurisdiction and are not likely to
result in the destruction or adverse modification of critical habitat
in the HSTT Study Area. The Biological Opinion for this action is
available at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.
National Marine Sanctuaries Act
Federal agencies are subject to the National Marine Sanctuaries Act
(NMSA), as applicable. NMFS has fulfilled its responsibilities and
completed all requirements under the NMSA.
National Environmental Policy Act
NMFS participated as a cooperating agency on the HSTT FEIS/OEIS,
which was published on October 26, 2018, and is available at https://www.hstteis.com/. In accordance with 40 CFR 1506.3, NMFS independently
reviewed and
[[Page 67019]]
evaluated the HSTT FEIS/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 adopted the Navy's HSTT
FEIS/OEIS. NMFS has prepared a separate Record of Decision. NMFS'
Record of Decision for adoption of the HSTT FEIS/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.
Classification
The Office of Management and Budget has determined that this final
rule is not significant for purposes of Executive Order 12866.
Pursuant to the Regulatory Flexibility Act (RFA), the Chief Counsel
for Regulation of the Department of Commerce has certified to the Chief
Counsel for Advocacy of the Small Business Administration that this
final rule will not have a significant economic impact on a substantial
number of small entities. The RFA requires Federal agencies to prepare
an analysis of a rule's impact on small entities whenever the agency is
required to publish a notice of proposed rulemaking. However, a Federal
agency may certify, pursuant to 5 U.S.C. 605(b), that the action will
not have a significant economic impact on a substantial number of small
entities. The Navy is the sole entity that would be affected by this
rulemaking, and the Navy is not a small governmental jurisdiction,
small organization, or small business, as defined by the RFA. Any
requirements imposed by an LOA issued pursuant to these regulations,
and any monitoring or reporting requirements imposed by these
regulations, would be applicable only to the Navy. Because this action
will directly affect the Navy and not a small entity, NMFS concludes
the action will not result in a significant economic impact on a
substantial number of small entities.
Waiver of Delay in Effective Date
NMFS has determined that there is good cause under the
Administrative Procedure Act (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 informed NMFS that it requests that this final rule take
effect on or by December 21, 2018, to accommodate the Navy's current
LOAs expiring December 24, 2018, so as to not cause a disruption in
training and testing activities. NMFS was unable to accommodate the 30-
day delay of effectiveness period due to the need for additional time
to consider additional mitigation measures presented by the Navy as
well as new analysis of information showing that incidental mortality
and serious injury of seven stocks previously analyzed is unlikely to
occur. 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 finalizing
the 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
rule 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 the rule is granting an exception to the
Navy and relieving restrictions under the MMPA, which is a separate
basis for waiving the 30-day effective date for the rule.
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: December 13, 2018.
Alan D. Risenhoover,
Acting 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:
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 H to part 218 to read as follows:
Subpart H--Taking and Importing Marine Mammals; U.S. Navy's Hawaii-
Southern California Training and Testing (HSTT)
Sec.
218.70 Specified activity and geographical region.
218.71 Effective dates.
218.72 Permissible methods of taking.
218.73 Prohibitions.
218.74 Mitigation requirements.
218.75 Requirements for monitoring and reporting.
218.76 Letters of Authorization.
218.77 Renewals and modifications of Letters of Authorization.
218.78 [Reserved]
218.79 [Reserved]
Subpart H--Taking and Importing Marine Mammals; U.S. Navy's Hawaii-
Southern California Training and Testing (HSTT)
Sec. 218.70 Specified activity and geographical region.
(a) Regulations in this subpart apply only to the U.S. 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 Hawaii-Southern California Training and Testing (HSTT) Study
Area, which includes established operating and warning areas across the
north-central Pacific Ocean, from the mean high tide line in Southern
California west to Hawaii and the International Date Line. The Study
Area includes the at-sea areas of three existing range complexes the
Hawaii Range Complex (HRC), the Southern California Range Complex
(SOCAL), and the Silver Strand Training Complex, and overlaps a portion
of the Point Mugu Sea Range (PMSR). Also included in the Study Area are
Navy pierside locations in Hawaii and Southern California, Pearl
Harbor, San Diego Bay, and the transit corridor on the high seas where
sonar training and testing may occur.
(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) Training. (i) Amphibious warfare;
(ii) Anti-submarine warfare;
(iii) Electronic warfare;
(iv) Expeditionary warfare;
(v) Mine warfare; and
(vi) Surface warfare.
(2) Testing. (i) Naval Air Systems Command Testing Activities;
(ii) Naval Sea System Command Testing Activities; and
(iii) Office of Naval Research Testing Activities.
[[Page 67020]]
Sec. 218.71 Effective dates.
Regulations in this subpart are effective December 21, 2018 through
December 20, 2023.
Sec. 218.72 Permissible methods of taking.
(a) Under LOAs issued pursuant to Sec. Sec. 216.106 of this
chapter and 218.76, the Holder of the LOAs (hereinafter ``Navy'') may
incidentally, but not intentionally, take marine mammals within the
area described in Sec. 218.70(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 and explosives, provided the activity is
in compliance with all terms, conditions, and requirements of these
regulations in this subpart and the applicable LOAs.
(b) The incidental take of marine mammals by the activities listed
in Sec. 218.80(c) is limited to the following species:
Table 1 to Sec. 218.72
------------------------------------------------------------------------
Species Stock
------------------------------------------------------------------------
Blue whale............................. Central North Pacific.
Blue whale............................. Eastern North Pacific.
Bryde's whale.......................... Eastern Tropical Pacific.
Bryde's whale.......................... Hawaii.
Fin whale.............................. CA/OR/WA.
Fin whale.............................. Hawaiian.
Humpback whale......................... CA/OR/WA.
Humpback whale......................... Central North Pacific.
Minke whale............................ CA/OR/WA.
Minke whale............................ Hawaii.
Sei whale.............................. Eastern North Pacific.
Sei whale.............................. Hawaii.
Gray whale............................. Eastern North Pacific.
Gray whale............................. Western North Pacific.
Sperm whale............................ CA/OR/WA.
Sperm whale............................ Hawaii.
Dwarf sperm whale...................... Hawaii.
Pygmy sperm whale...................... Hawaii.
Kogia whales........................... CA/OR/WA.
Baird's beaked whale................... CA/OR/WA.
Blainville's beaked whale.............. Hawaii.
Cuvier's beaked whale.................. CA/OR/WA.
Cuvier's beaked whale.................. Hawaii.
Longman's beaked whale................. Hawaii.
Mesoplodon spp......................... CA/OR/WA.
Bottlenose dolphin..................... California Coastal.
Bottlenose dolphin..................... CA/OR/WA Offshore.
Bottlenose dolphin..................... Hawaii Pelagic.
Bottlenose dolphin..................... Kauai & Niihau.
Bottlenose dolphin..................... Oahu.
Bottlenose dolphin..................... 4-Island.
Bottlenose dolphin..................... Hawaii.
False killer whale..................... Hawaii Pelagic.
False killer whale..................... Main Hawaiian Islands Insular.
False killer whale..................... Northwestern Hawaiian Islands.
Fraser's dolphin....................... Hawaii.
Killer whale........................... Eastern North Pacific (ENP)
Offshore.
Killer whale........................... ENP Transient/West Coast
Transient.
Killer whale........................... Hawaii.
Long-beaked common dolphin............. California.
Melon-headed whale..................... Hawaiian Islands.
Melon-headed whale..................... Kohala Resident.
Northern right whale dolphin........... CA/OR/WA.
Pacific white-sided dolphin............ CA/OR/WA.
Pantropical spotted dolphin............ Hawaii Island.
Pantropical spotted dolphin............ Hawaii Pelagic.
Pantropical spotted dolphin............ Oahu.
Pantropical spotted dolphin............ 4-Island.
Pygmy killer whale..................... Hawaii.
Pygmy killer whale..................... Tropical.
Risso's dolphin........................ CA/OR/WA.
Risso's dolphin........................ Hawaii.
Rough-toothed dolphin.................. Hawaii.
Short-beaked common dolphin............ CA/OR/WA.
Short-finned pilot whale............... CA/OR/WA.
Short-finned pilot whale............... Hawaii.
Spinner dolphin........................ Hawaii Island.
Spinner dolphin........................ Hawaii Pelagic.
Spinner dolphin........................ Kauai & Niihau.
Spinner dolphin........................ Oahu & 4-Island.
Striped dolphin........................ CA/OR/WA.
[[Page 67021]]
Striped dolphin........................ Hawaii.
Dall's porpoise........................ CA/OR/WA.
California sea lion.................... U.S.
Guadalupe fur seal..................... Mexico.
Northern fur seal...................... California.
Harbor seal............................ California.
Hawaiian monk seal..................... Hawaii.
Northern elephant seal................. California.
------------------------------------------------------------------------
Note to Table 1: CA/OR/WA = California/Oregon/Washington.
Sec. 218.73 Prohibitions.
Notwithstanding incidental takings contemplated in Sec. 218.72(a)
and authorized by LOAs issued under Sec. Sec. 216.106 of this chapter
and 218.76, no person in connection with the activities listed in Sec.
218.70(c) may:
(a) 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 218.76;
(b) Take any marine mammal not specified in Sec. 218.72(b);
(c) Take any marine mammal specified in Sec. 218.72(b) in any
manner other than as specified in the LOAs; or
(d) Take a marine mammal specified in Sec. 218.72(b) if NMFS
determines such taking results in more than a negligible impact on the
species or stocks of such marine mammal.
Sec. 218.74 Mitigation requirements.
When conducting the activities identified in Sec. 218.70(c), the
mitigation measures contained in any LOAs issued under Sec. Sec.
216.106 of this chapter and 218.76 must be implemented. These
mitigation measures include, but are not limited to:
(a) Procedural mitigation. Procedural mitigation is mitigation that
the Navy must implement whenever and wherever an applicable training or
testing activity takes place within the HSTT Study Area for each
applicable activity category or stressor category and includes acoustic
stressors (i.e., active sonar, air guns, pile driving, weapons firing
noise), explosive stressors (i.e., sonobuoys, torpedoes, medium-caliber
and large-caliber projectiles, missiles and rockets, bombs, sinking
exercises, mines, anti-swimmer grenades, and mat weave and obstacle
loading), 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 and rockets;
and non-explosive bombs and mine shapes).
(1) Environmental awareness and education. Appropriate Navy
personnel (including civilian personnel) involved in mitigation and
training or testing activity reporting under the specified activities
must 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, Marine Species Awareness
Training; U.S. Navy Protective Measures Assessment Protocol; and U.S.
Navy Sonar Positional Reporting System and Marine Mammal Incident
Reporting.
(2) Active sonar. Active sonar includes low-frequency active sonar,
mid-frequency active sonar, and high-frequency active sonar. For
vessel-based 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
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).
(i) Number of Lookouts and observation platform--(A) Hull-mounted
sources. 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) Sources that are not hull-mounted sources. One Lookout on the
ship or aircraft conducting the activity.
(ii) Mitigation zone and requirements. During the activity, at
1,000 yards (yd) Navy personnel must power down 6 decibels (dB), at 500
yd Navy personnel must power down an additional 4 dB (for a total of 10
dB), and 200 yd Navy personnel must shut down for low-frequency active
sonar >=200 dB and hull-mounted mid-frequency active sonar; or at 200
yd Navy personnnel must shut down for low-frequency active sonar <200
dB, mid-frequency active sonar sources that are not hull-mounted, and
high-frequency active sonar.
(A) Prior to the start of the activity (e.g., when maneuvering on
station), Navy personnel must observe the mitigation zone for floating
vegetation; if floating vegetation is observed, Navy personnel must
relocate or delay the start of active sonar transmission until the
mitigation zone is clear. Navy personnel must also observe the
mitigation zone for marine mammals; if marine mammals are observed,
Navy personnel must relocate or delay the start of active sonar
transmission.
(B) During the activity for low-frequency active sonar at or above
200 dB and hull-mounted mid-frequency active sonar, Navy personnel must
observe the mitigation zone for marine mammals and power down active
sonar transmission by 6 dB if marine mammals are observed within 1,000
yd of the sonar source; power down by an additional 4 dB (for a total
of 10 dB total) if marine mammals are observed within 500 yd of the
sonar source; and cease transmission if marine mammals are observed
within 200 yd of the sonar source.
(C) During the activity for low-frequency active sonar below 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 and cease active sonar transmission if marine
mammals are observed within 200 yd of the sonar source.
(D) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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
[[Page 67022]]
powering up active sonar transmission) until one of the following
conditions has been met: The animal is observed exiting the mitigation
zone; 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; 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; 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
for activities using hull-mounted sonar where a dolphin(s) is observed
in the mitigation zone, the Lookout concludes that the dolphin(s) 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).
(3) Air guns--(i) Number of Lookouts and observation platform. One
Lookout positioned on a ship or pierside.
(ii) Mitigation zone and requirements. 150 yd around the air gun.
(A) Prior to the initial start of the activity (e.g., when
maneuvering on station), Navy personnel must observe the mitigation
zone for floating vegetation; if floating vegetation is observed, Navy
personnel must relocate or delay the start until the mitigation zone is
clear. Navy personnel must also observe the mitigation zone for marine
mammals; if marine mammals are observed, Navy personnel must relocate
or delay the start of air gun use.
(B) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease air gun use.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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 air gun use) until one of the following conditions
has been met: The animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the air
gun; the mitigation zone has been clear from any additional sightings
for 30 min; or for mobile activities, the air gun has transited a
distance equal to double that of the mitigation zone size beyond the
location of the last sighting.
(4) Pile driving. Pile driving and pile extraction sound during
Elevated Causeway System training.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned on the shore, the elevated causeway, or a small boat.
(ii) Mitigation zone and requirements. 100 yd around the pile
driver.
(A) Prior to the initial start of the activity (for 30 min), Navy
personnel must observe the mitigation zone for floating vegetation; if
floating vegetation is observed, Navy personnel must delay the start
until the mitigation zone is clear. Navy personnel also must observe
the mitigation zone for marine mammals; if marine mammals are observed,
Navy personnel must delay the start of pile driving or vibratory pile
extraction.
(B) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease impact pile driving or vibratory pile extraction.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity. The 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 pile driving or pile extraction) until one of the
following conditions has been met: The animal is observed exiting the
mitigation zone; the animal is thought to have exited the mitigation
zone based on a determination of its course, speed, and movement
relative to the pile driving location; or the mitigation zone has been
clear from any additional sightings for 30 min.
(5) Weapons firing noise. Weapons firing noise associated with
large-caliber gunnery activities.
(i) 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 provided for under
``Explosive medium-caliber and large-caliber projectiles'' or under
``Small-, medium-, and large-caliber non-explosive practice munitions''
in paragraphs (a)(8)(i) and (a)(18)(i) of this section.
(ii) Mitigation zone and requirements. Thirty degrees on either
side of the firing line out to 70 yd from the muzzle of the weapon
being fired.
(A) Prior to the start of the activity, Navy personnel must observe
the mitigation zone for floating vegetation; if floating vegetation is
observed, Navy personnel must relocate or delay the start of weapons
firing until the mitigation zone is clear. Navy personnel must also
observe the mitigation zone for marine mammals; if marine mammals are
observed, Navy personnel must relocate or delay the start of weapons
firing.
(B) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease weapons firing.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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: The animal is observed exiting the mitigation
zone; 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; the mitigation zone has been clear from any additional
sightings for 30 min; or 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.
(6) Explosive sonobuoys--(i) Number of Lookouts and observation
platform. One Lookout must be positioned in an aircraft or on 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 while performing their regular duties.
(ii) Mitigation zone and requirements. 600 yd around an explosive
sonobuoy.
(A) 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 observe the mitigation zone for floating vegetation; if
floating vegetation is observed, Navy personnel must relocate or delay
the start of sonobuoy or source/receiver pair detonations until the
mitigation zone is clear. Navy personnel must conduct passive acoustic
monitoring for marine mammals and use information from detections to
assist visual observations. Navy personnel also must visually observe
the mitigation zone for marine mammals; if marine mammals are observed,
Navy personnel must relocate or delay the start of sonobuoy or source/
receiver pair detonations.
(B) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine
[[Page 67023]]
mammals are observed, Navy personnel must cease sonobuoy or source/
receiver pair detonations.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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: The animal is observed exiting the mitigation zone; 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 the mitigation zone has been clear from any additional
sightings for 10 min when the activity involves aircraft that have fuel
constraints (e.g., helicopter), or 30 min when the activity involves
aircraft that are not typically fuel constrained.
(D) 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 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), these Navy assets must assist in the visual
observation of the area where detonations occurred.
(7) Explosive torpedoes--(i) Number of Lookouts and observation
platform. One Lookout 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 while
performing their regular duties.
(ii) Mitigation zone and requirements. 2,100 yd around the intended
impact location.
(A) Prior to the initial start of the activity (e.g., during
deployment of the target), Navy personnel must observe the mitigation
zone for floating vegetation; if floating vegetation is observed, Navy
personnel must relocate or delay the start of firing until the
mitigation zone is clear. Navy personnel must conduct passive acoustic
monitoring for marine mammals and use the information from detections
to assist visual observations. Navy personnel must visually observe the
mitigation zone for marine mammals and jellyfish aggregations; if
marine mammals or jellyfish aggregations are observed, Navy personnel
must relocate or delay the start of firing.
(B) During the activity, Navy personnel must observe for marine
mammals and jellyfish aggregations; if marine mammals or jellyfish
aggregation are observed, Navy personnel must cease firing.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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: the animal is observed exiting the mitigation zone; 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 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.
(D) 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), these Navy assets must assist in the visual
observation of the area where detonations occurred.
(8) 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.
(i) Number of Lookouts and observation platform. One Lookout must
be on the vessel or aircraft conducting the activity. For activities
using explosive large-caliber projectiles, depending on the activity,
the Lookout could be the same as the one described in ``Weapons firing
noise'' in paragraph (a)(5)(i) 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 while performing
their regular duties.
(ii) Mitigation zone and requirements. (A) 200 yd around the
intended impact location for air-to-surface activities using explosive
medium-caliber projectiles.
(B) 600 yd around the intended impact location for surface-to-
surface activities using explosive medium-caliber projectiles.
(C) 1,000 yd around the intended impact location for surface-to-
surface activities using explosive large-caliber projectiles.
(D) Prior to the start of the activity (e.g., when maneuvering on
station), Navy personnel must observe the mitigation zone for floating
vegetation; if floating vegetation is observed, Navy personnel must
relocate or delay the start of firing until the mitigation zone is
clear. Navy personnel must observe the mitigation zone for marine
mammals; if marine mammals are observed, Navy personnel must relocate
or delay the start of firing.
(E) During the activity, Navy personnel must observe for marine
mammals; if marine mammals are observed, Navy personnel must cease
firing.
(F) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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: The animal is observed exiting the mitigation zone; 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; 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 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.
(G) 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
[[Page 67024]]
activity (e.g., providing range clearance), these Navy assets must
assist in the visual observation of the area where detonations
occurred.
(9) Explosive missiles and rockets. Aircraft-deployed explosive
missiles and rockets. Mitigation applies to activities using a surface
target.
(i) 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 while performing their regular
duties.
(ii) Mitigation zone and requirements. (A) 900 yd around the
intended impact location for missiles or rockets with 0.6-20 lb net
explosive weight.
(B) 2,000 yd around the intended impact location for missiles with
21-500 lb net explosive weight.
(C) 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; if floating vegetation is
observed, Navy personnel must relocate or delay the start of firing
until the mitigation zone is clear. Navy personnel must observe the
mitigation zone for marine mammals; if marine mammals are observed,
Navy personnel must relocate or delay the start of firing.
(D) During the activity, Navy personnel must observe for marine
mammals; if marine mammals are observed, Navy personnel must cease
firing.
(E) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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: The animal is observed exiting the mitigation zone; 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 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 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), these Navy assets will assist in the visual
observation of the area where detonations occurred.
(10) Explosive bombs--(i) 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 while performing their regular duties.
(ii) Mitigation zone and requirements. 2,500 yd around the intended
target.
(A) Prior to the initial start of the activity (e.g., when arriving
on station), Navy personnel must observe the mitigation zone for
floating vegetation; if floating vegetation is observed, Navy personnel
must relocate or delay the start of bomb deployment until the
mitigation zone is clear. Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must relocate or delay the start of bomb deployment.
(B) 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.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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: The animal is observed exiting the mitigation
zone; 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; the mitigation zone has been clear from any additional
sightings for 10 min; or 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.
(D) 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), these Navy assets must assist in the visual
observation of the area where detonations occurred.
(11) Sinking exercises--(i) Number of Lookouts and observation
platform. Two Lookouts (one must be positioned in an aircraft and one
must be positioned on a vessel). 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 while performing
their regular duties.
(ii) Mitigation zone and requirements. 2.5 nautical miles (nmi)
around the target ship hulk.
(A) Prior to the initial start of the activity (90 min prior to the
first firing), Navy personnel must conduct aerial observations of the
mitigation zone for floating vegetation; if floating vegetation is
observed, Navy personnel must delay the start of firing until the
mitigation zone is clear. Navy personnel also must conduct aerial
observations of the mitigation zone for marine mammals and jellyfish
aggregations; if marine mammals or jellyfish aggregations are observed,
Navy personnel must delay the start of firing.
(B) During the activity, Navy personnel must conduct passive
acoustic monitoring for marine mammals and use the information from
detections to assist visual observations. Navy personnel must visually
observe the mitigation zone for marine mammals from the vessel; if
marine mammals are observed, Navy personnel must cease firing.
Immediately after any planned or unplanned breaks in weapons firing of
longer than two hours, Navy personnel must observe the mitigation zone
for marine mammals from the aircraft and vessel; if marine mammals are
observed, Navy personnel must delay recommencement of firing.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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
[[Page 67025]]
conditions has been met: The animal is observed exiting the mitigation
zone; the animal is thought to have exited the mitigation zone based on
a determination of its course, speed, and movement relative to the
target ship hulk; or the mitigation zone has been clear from any
additional sightings for 30 min.
(D) After completion of the activity (for two hours after sinking
the vessel or until sunset, whichever comes first), 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), these Navy assets will assist in the visual
observation of the area where detonations occurred.
(12) Explosive mine countermeasure and neutralization activities--
(i) Number of Lookouts and observation platform. (A) One Lookout must
be positioned on a vessel or in an aircraft when implementing the
smaller mitigation zone.
(B) Two Lookouts (one must be positioned in an aircraft and one
must be on a small boat) when implementing the larger mitigation zone.
(C) 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 while performing their regular duties.
(ii) Mitigation zone and requirements. (A) 600 yd around the
detonation site for activities using 0.1-5 lb net explosive weight.
(B) 2,100 yd around the detonation site for activities using 6-650
lb net explosive weight (including high explosive target mines).
(C) 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; if
floating vegetation is observed, Navy personnel must relocate or delay
the start of detonations until the mitigation zone is clear. Navy
personnel must observe the mitigation zone for marine mammals; if
marine mammals are observed, Navy personnel must relocate or delay the
start of detonations.
(D) During the activity, Navy personnel must observe the mitigation
zone for marine mammals, concentrations of seabirds, and individual
foraging seabirds; if marine mammals, concentrations of seabirds, and
individual foraging seabirds are observed, Navy personnel must cease
detonations.
(E) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity or a sighting of seabird
concentrations or individual foraging seabirds during the 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) or
during the activity (by not recommencing detonations) until one of the
following conditions has been met: The animal is observed exiting the
mitigation zone; 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 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 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 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), these Navy assets must
assist in the visual observation of the area where detonations
occurred.
(13) Explosive mine neutralization activities involving Navy
divers--(i) Number of Lookouts and observation platform. (A) Two
Lookouts (two small boats with one Lookout each, or one Lookout must be
on a small boat and one must be in a rotary-wing aircraft) when
implementing the smaller mitigation zone.
(B) Four Lookouts (two small boats with two Lookouts each), and a
pilot or member of an aircrew must serve as an additional Lookout if
aircraft are used during the activity, when implementing the larger
mitigation zone.
(C) All divers placing the charges on mines will support the
Lookouts while performing their regular duties and will report
applicable sightings to their supporting small boat or Range Safety
Officer.
(D) 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 while performing their regular duties.
(ii) Mitigation zone and requirements. (A) 500 yd around the
detonation site during activities under positive control using 0.1-20
lb net explosive weight.
(B) 1,000 yd around the detonation site during all activities using
time-delay fuses (0.1-29 lb net explosive weight) and during activities
under positive control using 21-60 lb net explosive weight charges.
(C) Prior to the initial start of the activity (e.g., when
maneuvering on station for activities under positive control; 30 min
for activities using time-delay firing devices), Navy personnel must
observe the mitigation zone for floating vegetation; if floating
vegetation is observed, Navy personnel must relocate or delay the start
of detonations or fuse initiation until the mitigation zone is clear.
Navy personnel also must observe the mitigation zone for marine
mammals; if marine mammals are observed, Navy personnel must relocate
or delay the start of detonations or fuse initiation.
(D) During the activity, Navy personnel must observe the mitigation
zone for marine mammals, concentrations of seabirds, and individual
foraging seabirds (in the water and not on shore); if marine mammals,
concentrations of seabirds, and individual foraging seabirds are
observed, Navy personnel must cease detonations or fuse initiation. To
the maximum extent practicable depending on mission requirements,
safety, and environmental conditions, Navy personnel must position
boats near the mid-point 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 (when two boats are used),
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. If
used, Navy aircraft must travel in a circular pattern around the
detonation location to the maximum extent practicable. Navy personnel
must not set time-delay firing devices (0.1-29 lb. net explosive
weight) to exceed 10 min.
(E) During activities conducted in shallow water, a shore-based
Navy observer must survey the mitigation zone with binoculars for birds
before and after each detonation. If training involves multiple
detonations, the second (or third, etc.) detonation will occur either
immediately after the
[[Page 67026]]
preceding detonation (i.e., within 10 seconds) or after 30 min to avoid
potential impacts on birds foraging underwater.
(F) Commencement/recommencement conditions after a marine mammal
sighting before or during the activity or a sighting of seabird
concentrations or individual foraging seabirds during the 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) or
during the activity (by not recommencing detonations) until one of the
following conditions has been met: the animal is observed exiting the
mitigation zone; 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 the mitigation zone has been clear
from any additional sightings for 10 min during activities under
positive control with aircraft that have fuel constraints, or 30 min
during activities under positive control with aircraft that are not
typically fuel constrained and during activities using time-delay
firing devices.
(G) After completion of an activity (for 30 min), the Navy must
observe for marine mammals for 30 min. 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), these Navy
assets must assist in the visual observation of the area where
detonations occurred.
(14) Maritime security operations--anti-swimmer grenades--(i)
Number of Lookouts and observation platform. One Lookout must be
positioned on the small boat 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 while
performing their regular duties.
(ii) Mitigation zone and requirements. 200 yd around the intended
detonation location.
(A) Prior to the initial start of the activity (e.g., when
maneuvering on station), Navy personnel must observe the mitigation
zone for floating vegetation; if floating vegetation is observed, Navy
personnel must relocate or delay the start of detonations until the
mitigation zone is clear. Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must relocate or delay the start of detonations.
(B) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease detonations.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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: the animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the
intended detonation location; the mitigation zone has been clear from
any additional sightings for 30 min; or the intended detonation
location has transited a distance equal to double that of the
mitigation zone size beyond the location of the last sighting.
(D) 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), these Navy assets will assist in the visual
observation of the area where detonations occurred.
(15) Underwater demolition multiple charge--mat weave and obstacle
loading exercises--(i) Number of Lookouts and observation platform. Two
Lookouts (one must be positioned on a small boat and one must be
positioned on shore from an elevated platform). 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 while performing
their regular duties.
(ii) Mitigation zone and requirements. 700 yd around the intended
detonation location.
(A) Prior to the initial start of the activity, or 30 min prior to
the first detonation, the Lookout positioned on a small boat must
observe the mitigation zone for floating vegetation and marine mammals;
if floating vegetation or marine mammals are observed, Navy personnel
must delay the start of detonations. For 10 min prior to the first
detonation, the Lookout positioned on shore must use binoculars to
observe the mitigation zone for marine mammals; if marine mammals are
observed, Navy personnel must delay the start of detonations until the
mitigation zone has been clear of any additional sightings for a
minimum of 10 min.
(B) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease detonations.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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: the animal is observed exiting the mitigation zone; the
animal is thought to have exited the mitigation zone based on a
determination of its course, speed, and movement relative to the
detonation location; or the mitigation zone has been clear from any
additional sightings for 10 min (as determined by the Navy shore
observer).
(D) After completion of the activity (for 30 min), the Lookout
positioned on a small boat 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), these Navy assets must
assist in the visual observation of the area where detonations
occurred.
(16) 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); the vessel is operated
autonomously; or when impracticable based on mission requirements
(e.g., during Amphibious Assault--Battalion Landing exercise).
(i) Number of Lookouts and observation platform. One Lookout must
be on the vessel that is underway.
(ii) Mitigation zone and requirements. (A) 500 yd around whales.
(B) 200 yd around all other marine mammals (except bow-riding
dolphins and pinnipeds hauled out on man-made
[[Page 67027]]
navigational structures, port structures, and vessels).
(iii) During the 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.
(iv) Incident reporting procedures. Additionally, if a marine
mammal vessel strike occurs, Navy personnel must follow the established
incident reporting procedures.
(17) Towed in-water devices. Mitigation applies to devices that are
towed from a manned surface platform or manned aircraft. The mitigation
will not be applied if the safety of the towing platform or in-water
device is threatened.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned on a manned towing platform.
(ii) Mitigation zone and requirements. 250 yd around marine
mammals.
(iii) During the activity. During the activity (i.e., when towing
an in-water device), Navy personnel must observe the mitigation zone
for marine mammals; if marine mammals are observed, Navy personnel must
maneuver to maintain distance.
(18) Small-, medium-, and large-caliber non-explosive practice
munitions. Mitigation applies to activities using a surface target.
(i) 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)(5)(i) of this section.
(ii) Mitigation zone and requirements. 200 yd around the intended
impact location.
(A) Prior to the start of the activity (e.g., when maneuvering on
station), Navy personnel must observe the mitigation zone for floating
vegetation; if floating vegetation is observed, Navy personnel must
relocate or delay the start of firing until the mitigation zone is
clear. Navy personnel must observe the mitigation zone for marine
mammals; if marine mammals are observed, Navy personnel must relocate
or delay the start of firing.
(B) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease firing.
(C) Commencement/recommencement conditions after a marine mammal
sighting before or during the 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: the animal is observed exiting the mitigation zone; 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; 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 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.
(19) Non-explosive missiles and rockets. Aircraft-deployed non-
explosive missiles and rockets. Mitigation applies to activities using
a surface target.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned in an aircraft.
(ii) Mitigation zone and requirements. 900 yd around the intended
impact location.
(A) 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; if floating vegetation is
observed, Navy personnel must relocate or delay the start of firing
until the mitigation zone is clear. Navy personnel must observe the
mitigation zone for marine mammals; if marine mammals are observed,
Navy personnel must relocate or delay the start of firing.
(B) During the activity, Navy personnel must observe the mitigation
zone for marine mammals; if marine mammals are observed, Navy personnel
must cease firing.
(C) Commencement/recommencement conditions after a marine mammal
sighting prior to or during the 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: the animal is observed exiting the mitigation zone; 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 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.
(20) Non-explosive bombs and mine shapes. Non-explosive bombs and
non-explosive mine shapes during mine laying activities.
(i) Number of Lookouts and observation platform. One Lookout must
be positioned in an aircraft.
(ii) Mitigation zone and requirements. 1,000 yd around the intended
target.
(A) Prior to the initial start of the activity (e.g., when arriving
on station), Navy personnel must observe the mitigation zone for
floating vegetation; if floating vegetation is observed, Navy personnel
must relocate or delay the start of bomb deployment or mine laying
until the mitigation zone is clear. Navy personnel also must observe
the mitigation zone for marine mammals; if marine mammals are observed,
Navy personnel must relocate or delay the start of bomb deployment or
mine laying.
(B) During the activity (e.g., during approach of the target or
intended minefield location), Navy personnel must observe the
mitigation zone for marine mammals and, if marine mammals are observed,
Navy personnel must cease bomb deployment or mine laying.
(C) Commencement/recommencement conditions after a marine mammal
sighting prior to or during the 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: the animal is observed exiting the
mitigation zone; 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; the mitigation
zone has been clear from any additional sightings for 10 min; or 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.
(b) 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.
(1) Mitigation areas for marine mammals in the Hawaii Range Complex
for sonar, explosives, and vessel strikes--(i) Mitigation area
requirements--(A) Hawaii Island Mitigation Area (year-round). (1)
Except as provided in paragraph (b)(1)(i)(A)(2)
[[Page 67028]]
of this section, Navy personnel must not conduct more than 300 hours of
MF1 surface ship hull-mounted mid-frequency active sonar or 20 hours of
MF4 dipping sonar annually, or use explosives that could potentially
result in takes of marine mammals during training and testing.
(2) Should national security require conduct of more than 300 hours
of MF1 surface ship hull-mounted mid-frequency active sonar or 20 hours
of MF4 dipping sonar, or use of explosives that could potentially
result in the take of marine mammals during training or testing, Naval
units 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 the information
(e.g., sonar hours or explosives usage) in its annual activity reports
submitted to NMFS.
(B) 4-Islands Region Mitigation Area (November 15-April 15 for
active sonar; year-round for explosives). (1) Except as provided in
paragraph (b)(1)(i)(B)(2) of this section, Navy personnel must not use
MF1 surface ship hull-mounted mid-frequency active sonar or explosives
that could potentially result in takes of marine mammals during
training and testing.
(2) Should national security require use of MF1 surface ship hull-
mounted mid-frequency active sonar or explosives that could potentially
result in the take of marine mammals during training or testing, Naval
units 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 the information
(e.g., sonar hours or explosives usage) in its annual activity reports
submitted to NMFS.
(C) Humpback Whale Special Reporting Areas (December 15-April 15).
Navy personnel must report the total hours of surface ship hull-mounted
mid-frequency active sonar used in the special reporting areas in its
annual training and testing activity reports submitted to NMFS.
(D) Humpback Whale Awareness Notification Message Area (November-
April). (1) Navy personnel must issue a seasonal awareness notification
message to alert ships and aircraft operating in the area to the
possible presence of concentrations of large whales, including humpback
whales.
(2) To maintain safety of navigation and to avoid interactions with
large whales during transits, Navy personnel must instruct vessels to
remain vigilant to the presence of large whale species (including
humpback whales), that when concentrated seasonally, may become
vulnerable to vessel strikes.
(3) Platforms must use the information from the awareness
notification message to assist their visual observation of applicable
mitigation zones during training and testing activities and to aid in
the implementation of procedural mitigation.
(ii) [Reserved]
(2) Mitigation areas for marine mammals in the Southern California
portion of the study area for sonar, explosives, and vessel strikes--
(i) Mitigation area requirements--(A) San Diego Arc, San Nicolas
Island, and Santa Monica/Long Beach Mitigation Areas (June 1-October
31). (1) Except as provided in paragraph (b)(2)(i)(A)(2) of this
section, Navy personnel must not conduct more than a total of 200 hours
of MF1 surface ship hull-mounted mid-frequency active sonar in the
combined areas, excluding normal maintenance and systems checks, during
training and testing.
(2) Should national security require conduct of more than 200 hours
of MF1 surface ship hull-mounted mid-frequency active sonar in the
combined areas during training and testing (excluding normal
maintenance and systems checks), Naval units 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 the information (e.g., sonar hours) in its
annual activity reports submitted to NMFS.
(3) Except as provided in paragraph (b)(2)(i)(A)(4) of this
section, within the San Diego Arc Mitigation Area, Navy personnel must
not use explosives that could potentially result in the take of marine
mammals during large-caliber gunnery, torpedo, bombing, and missile
(including 2.75-inch rockets) activities during training and testing.
(4) Should national security require use of explosives that could
potentially result in the take of marine mammals during large-caliber
gunnery, torpedo, bombing, and missile (including 2.75-inch rockets)
activities during training or testing within the San Diego Arc
Mitigation Area, Naval units 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 the information (e.g., explosives usage) in its annual
activity reports submitted to NMFS.
(5) Except as provided in paragraph (b)(2)(i)(A)(6) of this
section, within the San Nicolas Island Mitigation Area, Navy personnel
must not use explosives that could potentially result in the take of
marine mammals during mine warfare, large-caliber gunnery, torpedo,
bombing, and missile (including 2.75-inch rockets) activities during
training.
(6) Should national security require use of explosives that could
potentially result in the take of marine mammals during mine warfare,
large-caliber gunnery, torpedo, bombing, and missile (including 2.75-
inch rockets) activities during training in the San Nicolas Island
Mitigation Area, Naval units 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 the information (e.g., explosives usage) in its annual
activity reports submitted to NMFS.
(7) Except as provided in paragraph (b)(2)(i)(A)(8) of this
section, within the Santa Monica/Long Beach Mitigation Area, Navy
personnel must not use explosives that could potentially result in the
take of marine mammals during mine warfare, large-caliber gunnery,
torpedo, bombing, and missile (including 2.75-inch rockets) activities
during training and testing.
(8) Should national security require use of explosives that could
potentially result in the take of marine mammals during mine warfare,
large-caliber gunnery, torpedo, bombing, and missile (including 2.75-
inch rockets) activities during training or testing in the Santa
Monica/Long Beach Mitigation Area, Naval units 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 the information (e.g., explosives usage) in
its annual activity reports submitted to NMFS.
(B) Santa Barbara Island Mitigation Area (year-round). (1) Except
as provided in paragraph (b)(2)(i)(B)(2) of this section, Navy
personnel must not use MF1 surface ship hull-mounted mid-frequency
active sonar during training or testing, or explosives that could
potentially result in the take of marine mammals during medium-caliber
or large-caliber gunnery, torpedo, bombing, and missile (including
2.75-inch rockets) activities during training.
(2) Should national security require use of MF1 surface ship hull-
mounted mid-frequency active sonar during training or testing, or
explosives that
[[Page 67029]]
could potentially result in the take of marine mammals during medium-
caliber or large-caliber gunnery, torpedo, bombing, and missile
(including 2.75-inch rockets) activities during training, Naval units
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 the information
(e.g., sonar hours or explosives usage) in its annual activity reports
submitted to NMFS.
(C) Blue Whale (June-October), Gray Whale (November-March), and Fin
Whale (November-May) Awareness Notification Message Areas. (1) Navy
personnel must issue a seasonal awareness notification message to alert
ships and aircraft operating in the area to the possible presence of
concentrations of large whales, including blue whales, gray whales, and
fin whales.
(2) To maintain safety of navigation and to avoid interactions with
large whales during transits, Navy personnel must instruct vessels to
remain vigilant to the presence of large whale species, that when
concentrated seasonally, may become vulnerable to vessel strikes.
(3) 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.
(ii) [Reserved]
Sec. 218.75 Requirements for monitoring and reporting.
(a) Unauthorized take. Navy personnel must notify NMFS immediately
(or as soon as operational security considerations allow) if the
specified activity identified in Sec. 218.70 is thought to have
resulted in the mortality or serious injury of any marine mammals, or
in any Level A or Level B harassment take 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 HSTT Study Area 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 www.fisheries.noaa.gov/national/marine-mammal-protection/incidentaltake-authorizations-military-readinessactivities.
(d) Annual HSTT Study Area marine species monitoring report. The
Navy must submit an annual report of the HSTT Study Area monitoring
describing the implementation and results from the previous calendar
year. Data collection methods must be standardized across range
complexes and study areas to allow for comparison in different
geographic locations. The report must be submitted to the Director,
Office of Protected Resources, NMFS, either three months after the end
of the calendar year, or three months after the conclusion of the
monitoring year, to be determined by the Adaptive Management process.
This report will describe progress of knowledge made with respect to
intermediate scientific objectives within the HSTT Study Area
associated with the Integrated Comprehensive Monitoring Program (ICMP).
Similar study questions must be treated together so that progress on
each topic must 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. As an alternative, the Navy may submit a multi-Range Complex
annual Monitoring Plan report to fulfill this requirement. Such a
report will describe progress of knowledge made with respect to
monitoring study questions across multiple Navy ranges associated with
the ICMP. Similar study questions must be treated together so that
progress on each topic can be 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 study
question. 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 HSTT, Gulf of Alaska, Mariana
Islands, and Northwest Study Areas.
(e) Annual HSTT Study Area training exercise report and testing
activity report. Each year, the Navy must submit two preliminary
reports (Quick Look Report) detailing the status of authorized sound
sources within 21 days after the anniversary of the date of issuance of
each LOA to the Director, Office of Protected Resources, NMFS. Each
year, the Navy must submit detailed reports to the Director, Office of
Protected Resources, NMFS, within 3 months after the one-year
anniversary of the date of issuance of the LOA. The HSTT annual
Training Exercise Report and Testing Activity Report can be
consolidated with other exercise reports from other range complexes in
the Pacific Ocean for a single Pacific Exercise Report, if desired. The
annual reports must contain information on major training exercises
(MTEs), Sinking Exercise (SINKEX) events, and a summary of all sound
sources used, including within specific mitigation reporting areas as
described in paragraph (e)(3) of this section. The analysis in the
detailed reports must be based on the accumulation of data from the
current year's report and data collected from previous reports. The
detailed reports must contain information identified in paragraphs
(e)(1) through (7) of this section.
(1) MTEs. This section of the report must contain the following
information for MTEs conducted in the HSTT Study Area.
(i) Exercise Information (for each MTE).
(A) Exercise designator.
(B) Date that exercise began and ended.
(C) Location.
(D) Number and types of active sonar sources used in the exercise.
(E) Number and types of passive acoustic sources used in exercise.
(F) Number and types of vessels, aircraft, and other platforms
participating in exercise.
(G) Total hours of all active sonar source operation.
(H) Total hours of each active sonar source bin.
(I) Wave height (high, low, and average) during exercise.
(ii) Individual marine mammal sighting information for each
sighting in each exercise when mitigation occurred:
(A) Date/Time/Location of sighting.
(B) Species (if not possible, indication of whale/dolphin/
pinniped).
(C) Number of individuals.
(D) Initial Detection Sensor (e.g., sonar, Lookout).
(E) Indication of specific type of platform observation was made
from (including, for example, what type of surface vessel or testing
platform).
(F) Length of time observers maintained visual contact with marine
mammal.
(G) Sea state.
(H) Visibility.
(I) Sound source in use at the time of sighting.
(J) Indication of whether animal was less than 200 yd, 200 to 500
yd, 500 to 1,000 yd, 1,000 to 2,000 yd, or greater than 2,000 yd from
sonar source.
[[Page 67030]]
(K) Whether operation of sonar sensor was delayed, or sonar was
powered or shut down, and how long the delay.
(L) If source in use was hull-mounted, true bearing of animal from
the vessel, true direction of vessel's travel, and estimation of
animal's motion relative to vessel (opening, closing, parallel).
(M) Lookouts must report, in plain language and without trying to
categorize in any way, the observed behavior of the animal(s) (such as
animal closing to bow ride, paralleling course/speed, floating on
surface and not swimming, etc.) and if any calves were present.
(iii) An evaluation (based on data gathered during all of the MTEs)
of the effectiveness of mitigation measures designed to minimize the
received level to which marine mammals may be exposed. This evaluation
must identify the specific observations that support any conclusions
the Navy reaches about the effectiveness of the mitigation.
(2) SINKEXs. This section of the report must include the following
information for each SINKEX completed that year.
(i) Exercise information (gathered for each SINKEX).
(A) Location.
(B) Date and time exercise began and ended.
(C) Total hours of observation by Lookouts before, during, and
after exercise.
(D) Total number and types of explosive source bins detonated.
(E) Number and types of passive acoustic sources used in exercise.
(F) Total hours of passive acoustic search time.
(G) Number and types of vessels, aircraft, and other platforms,
participating in exercise.
(H) Wave height in feet (high, low, and average) during exercise.
(I) Narrative description of sensors and platforms utilized for
marine mammal detection and timeline illustrating how marine mammal
detection was conducted.
(ii) Individual marine mammal observation (by Navy Lookouts)
information (gathered for each marine mammal sighting) for each
sighting where mitigation was implemented.
(A) Date/Time/Location of sighting.
(B) Species (if not possible, indicate whale, dolphin, or
pinniped).
(C) Number of individuals.
(D) Initial detection sensor (e.g., sonar or Lookout).
(E) Length of time observers maintained visual contact with marine
mammal.
(F) Sea state.
(G) Visibility.
(H) Whether sighting was before, during, or after detonations/
exercise, and how many minutes before or after.
(I) Distance of marine mammal from actual detonations (or target
spot if not yet detonated): Less than 200 yd, 200 to 500 yd, 500 to
1,000 yd, 1,000 to 2,000 yd, or greater than 2,000 yd.
(J) Lookouts must report, in plain language and without trying to
categorize in any way, the observed behavior of the animal(s) (such as
animal closing to bow ride, paralleling course/speed, floating on
surface and not swimming etc.), including speed and direction and if
any calves were present.
(K) The report must indicate whether explosive detonations were
delayed, ceased, modified, or not modified due to marine mammal
presence and for how long.
(L) If observation occurred while explosives were detonating in the
water, indicate munition type in use at time of marine mammal
detection.
(3) 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) Total annual hours or quantity (per the LOA) of each bin of
sonar or other acoustic sources (e.g., pile driving and air gun
activities); and
(ii) Total annual expended/detonated ordinance (missiles, bombs,
sonobuoys, etc.) for each explosive bin.
(4) Humpback Whale Special Reporting Area (December 15--April 15).
The Navy must report the total hours of operation of surface ship hull-
mounted mid-frequency active sonar used in the special reporting area.
(5) HSTT Study Area Mitigation Areas. The Navy must report any use
that occurred as specifically described in these areas. Information
included in the classified annual reports may be used to inform future
adaptive management of activities within the HSTT Study Area.
(6) Geographic information presentation. The reports must present
an annual (and seasonal, where practical) depiction of training and
testing bin usage (as well as pile driving activities) geographically
across the HSTT Study Area.
(7) Sonar exercise notification. The Navy must submit to NMFS
(contact as specified in the LOA) an electronic report within fifteen
calendar days after the completion of any MTE indicating:
(i) Location of the exercise;
(ii) Beginning and end dates of the exercise; and
(iii) Type of exercise.
Sec. 218.76 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) LOAs, unless suspended or revoked, may be effective for a
period of time not to exceed December 20, 2023.
(c) If an LOA expires prior to December 20, 2023, 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. 218.77(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. 218.77.
(e) Each LOA must 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 or 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 must be 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) must be published in
the Federal Register within 30 days of a determination.
Sec. 218.77 Renewals and modifications of Letters of Authorization.
(a) An LOA issued under Sec. Sec. 216.106 of this chapter and
218.76 for the activity identified in Sec. 218.70(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 LOA(s) 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
[[Page 67031]]
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
218.76 may be modified by NMFS under the following circumstances:
(1) Adaptive management. 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.
(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 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 the regulations in
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) Emergencies. 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 218.76, an LOA may be modified without prior notice
or opportunity for public comment. Notice would be published in the
Federal Register within thirty days of the action.
Sec. Sec. 218.78-218.79 [Reserved]
[FR Doc. 2018-27342 Filed 12-20-18; 8:45 am]
BILLING CODE 3510-22-P