[Federal Register Volume 78, Number 21 (Thursday, January 31, 2013)]
[Proposed Rules]
[Pages 6978-7048]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-01808]



[[Page 6977]]

Vol. 78

Thursday,

No. 21

January 31, 2013

Part III





Department of Commerce





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National Oceanic and Atmospheric Administration





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50 CFR Part 218





 Takes of Marine Mammals Incidental to Specified Activities; U.S. Navy 
Training and Testing Activities in the Hawaii-Southern California 
Training and Testing Study Area; Proposed Rule

  Federal Register / Vol. 78, No. 21 / Thursday, January 31, 2013 / 
Proposed Rules  

[[Page 6978]]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 218

[Docket No. 130107014-3024-01]
RIN 0648-BC52


Takes of Marine Mammals Incidental to Specified Activities; 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: Proposed rule; request for comments and information.

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SUMMARY: NMFS has received a request from the U.S. Navy (Navy) for 
authorization to take marine mammals incidental to the training and 
testing activities conducted in the Hawaii-Southern California Training 
and Testing (HSTT) study area from January 2014 through January 2019. 
Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting 
comments on its proposal to issue regulations and subsequent Letters of 
Authorization (LOAs) to the Navy to incidentally harass marine mammals.

DATES: Comments and information must be received no later than March 
11, 2013.

ADDRESSES: You may submit comments, identified by 0648-BC52, by either 
of the following methods:
     Electronic submissions: Submit all electronic public 
comments via the Federal eRulemaking Portal http://www.regulations.gov.
     Hand delivery or mailing of paper, disk, or CD-ROM 
comments should be addressed to P. Michael Payne, Chief, Permits and 
Conservation Division, Office of Protected Resources, National Marine 
Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910-
3225.
    Instructions: All comments received are a part of the public record 
and will generally be posted to http://www.regulations.gov without 
change. All Personal Identifying Information (for example, name, 
address, etc.) voluntarily submitted by the commenter may be publicly 
accessible. Do not submit Confidential Business Information or 
otherwise sensitive or protected information.
    NMFS will accept anonymous comments (enter N/A in the required 
fields if you wish to remain anonymous). Attachments to electronic 
comments will be accepted in Microsoft Word, Excel, WordPerfect, or 
Adobe PDF file formats only.

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

SUPPLEMENTARY INFORMATION:

Availability

    A copy of the Navy's application may be obtained by visiting the 
internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications. The Navy's Draft Environmental Impact 
Statement/Overseas Environmental Impact Statement (DEIS/OEIS) for HSTT 
was made available to the public on May 11, 2012 (77 FR 27743) and may 
also be viewed at http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications. Documents cited in this notice may also be 
viewed, by appointment, during regular business hours, at the 
aforementioned address.

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce 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.
    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 and requirements 
pertaining to the mitigation, monitoring, and reporting of such takings 
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103 
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.''
    The National Defense Authorization Act of 2004 (NDAA) (Pub. L. 108-
136) removed the ``small numbers'' and ``specified geographical 
region'' limitations indicated above and amended the definition of 
``harassment'' as applies to a ``military readiness activity'' to read 
as follows (section 3(18)(B) of the MMPA): ``(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].''

Summary of Request

    On April 13, 2012, NMFS received an application from the Navy 
requesting two LOAs for the take of 39 species of marine mammals 
incidental to Navy training and testing activities to be conducted in 
the HSTT Study Area over 5 years. The Navy submitted an addendum on 
September 24, 2012 and the application was considered complete. The 
Navy is requesting regulations that would establish a process for 
authorizing take, via two separate 5-year LOAs, of marine mammals for 
training activities and testing activities, each proposed to be 
conducted from 2014 through 2019. The Study Area includes three 
existing range complexes (Southern California (SOCAL) Range Complex, 
Hawaii Range Complex (HRC), and Silver Strand Training Complex (SSTC)) 
plus pierside locations and areas on the high seas where maintenance, 
training, or testing may occur. The proposed activities are classified 
as military readiness activities. Marine mammals present in the Study 
Area may be exposed to sound from active sonar, underwater detonations, 
and/or pile driving and removal. In addition, incidental takes of 
marine mammals may occur from ship strikes. The Navy is requesting 
authorization to take 38 marine mammal species by Level B harassment 
and 24 marine mammal species by Level A harassment or mortality.
    The Navy's application and the HSTT DEIS/OEIS contain proposed 
acoustic criteria and thresholds that would, in some instances, 
represent changes from what NMFS has used to evaluate the Navy's 
proposed activities for past incidental take authorizations. The 
revised thresholds are based on evaluation of recent scientific 
studies; a detailed explanation of how they were derived is provided in 
the HSTT DEIS/OEIS Criteria and Thresholds Technical Report. NMFS is 
currently updating and revising all of its acoustic criteria and 
thresholds. Until that process is complete, NMFS will continue its 
long-standing practice of considering specific

[[Page 6979]]

modifications to the acoustic criteria and thresholds currently 
employed for incidental take authorizations only after providing the 
public with an opportunity for review and comment. NMFS is requesting 
comments on all aspects of the proposed rule, and specifically requests 
comments on the proposed acoustic criteria and thresholds.

Background of Request

    The Navy's mission is to maintain, train, and equip combat-ready 
naval forces capable of winning wars, deterring aggression, and 
maintaining freedom of the seas. Section 5062 of Title 10 of the United 
States Code directs the Chief of Naval Operations to train all military 
forces for combat. The Chief of Naval Operations meets that direction, 
in part, by conducting at-sea training exercises and ensuring naval 
forces have access to ranges, operating areas (OPAREAs) and airspace 
where they can develop and maintain skills for wartime missions and 
conduct research, development, testing, and evaluation (RDT&E) of naval 
systems.
    The Navy proposes to continue conducting training and testing 
activities within the HSTT Study Area, which have been ongoing since 
the 1940s. Recently, most of these activities were analyzed in three 
separate EISs completed between 2008 and 2011; the Hawaii Range Complex 
(HRC) EIS/OEIS (U.S. Department of the Navy, 2008a), the Southern 
California (SOCAL) Range Complex EIS/OEIS (U.S. Department of the Navy, 
2008b), and the Silver Strand Training Complex (SSTC) EIS (U.S. 
Department of the Navy, 2011a). These documents, among others, and 
their associated MMPA regulations and authorizations, describe the 
baseline of training and testing activities currently conducted in the 
Study Area. The tempo and types of training and testing activities have 
fluctuated due to changing requirements; new technologies; the dynamic 
nature of international events; advances in warfighting doctrine and 
procedures; and changes in basing locations for ships, aircraft, and 
personnel. Such developments influence the frequency, duration, 
intensity, and location of required training and testing. The Navy's 
LOA request covers training and testing activities that would occur for 
a 5-year period following the expiration of the current MMPA 
authorizations. The Navy has also prepared a DEIS/OEIS analyzing the 
effects on the human environment of implementing their preferred 
alternative (among others).

Description of the Specified Activity

    The Navy is requesting authorization to take marine mammals 
incidental to conducting training and testing activities. The Navy has 
determined that sonar use, underwater detonations, pile driving and 
removal, and ship strike are the stressors most likely to result in 
impacts on marine mammals that could rise to the level of harassment. 
Detailed descriptions of these activities are provided in the HSTT 
DEIS/OEIS and LOA application (http://www.nmfs.noaa.gov/pr/permits/incidental.htm) and are summarized here.

Overview of Training Activities

    The Navy routinely trains in the HSTT Study Area in preparation for 
national defense missions. Training activities are categorized into 
eight functional warfare areas (anti-air warfare; amphibious warfare; 
strike warfare; anti-surface warfare; anti-submarine warfare; 
electronic warfare; mine warfare; and naval special warfare). The Navy 
determined that the following stressors used in these warfare areas are 
most likely to result in impacts on marine mammals:
     Amphibious warfare (underwater detonations, pile driving 
and removal)
     Anti-surface warfare (underwater detonations)
     Anti-submarine warfare (active sonar, underwater 
detonations)
     Mine warfare (active sonar, underwater detonations, and 
marine mammal systems (see description below))
     Naval special warfare (underwater detonations)
    The Navy's activities in anti-air warfare, strike warfare, and 
electronic warfare do not involve stressors that could result in 
harassment of marine mammals. Therefore, these activities are not 
discussed further.

Amphibious Warfare

    The mission of amphibious warfare is to project military power from 
the sea to the shore through the use of naval firepower and Marine 
Corps landing forces. The Navy uses amphibious warfare to attack a 
threat located on land by a military force embarked on ships. 
Amphibious warfare training ranges from individual, crew, and small 
unit events to large task force exercises. Individual and crew training 
include amphibious vehicles and naval gunfire support training for 
shore assaults, boat raids, airfield or port seizures, and 
reconnaissance. Large-scale amphibious exercises involve ship-to-shore 
maneuver, naval fire support, such as shore bombardment, and air strike 
and close air support training. However, the Navy only analyzed those 
portions of amphibious warfare training that occur at sea, in 
particular, underwater detonations associated with naval gunfire 
support training. The Navy conducts other amphibious warfare support 
activities that could potentially affect marine mammals (such as pile 
driving and removal) in the near shore region from the beach to about 
914 meters (m) from shore.

Anti-Surface Warfare

    The mission of anti-surface warfare is to defend against enemy 
ships or boats. When conducting anti-surface warfare, aircraft use 
cannons, air-launched cruise missiles, or other precision-guided 
munitions; ships use torpedoes, naval guns, and surface-to-surface 
missiles; and submarines use torpedoes or submarine-launched, anti-ship 
cruise missiles. Anti-surface warfare training includes surface-to-
surface gunnery and missile exercises, air-to-surface gunnery and 
missile exercises, and submarine missile or exercise torpedo launch 
events.

Anti-Submarine Warfare

    The mission of anti-submarine warfare is to locate, neutralize, and 
defeat hostile submarine threats to surface forces. Anti-submarine 
warfare is based on the principle of a layered defense of surveillance 
and attack aircraft, ships, and submarines all searching for hostile 
submarines. These forces operate together or independently to gain 
early warning and detection, and to localize, track, target, and attack 
hostile submarine threats. Anti-submarine warfare training addresses 
basic skills such as detection and classification of submarines, 
distinguishing between sounds made by enemy submarines and those of 
friendly submarines, ships, and marine life. More advanced, integrated 
anti-submarine warfare training exercises are conducted in coordinated, 
at-sea training events involving submarines, ships, and aircraft. This 
training integrates the full spectrum of anti-submarine warfare from 
detecting and tracking a submarine to attacking a target using either 
exercise torpedoes or simulated weapons.

Mine Warfare

    The mission of mine warfare is to detect, and avoid or neutralize 
mines to protect Navy ships and submarines and to maintain free access 
to ports and shipping lanes. Mine warfare also includes offensive mine 
laying to gain control or deny the enemy access to sea

[[Page 6980]]

space. Naval mines can be laid by ships, submarines, or aircraft. Mine 
warfare training includes exercises in which ships, aircraft, 
submarines, underwater vehicles, or marine mammal detection systems 
search for mines. Certain personnel train to destroy or disable mines 
by attaching and detonating underwater explosives to simulated mines. 
Other neutralization techniques involve impacting the mine with a 
bullet-like projectile or intentionally triggering the mine to 
detonate.
    Finally, the Navy deploys California sea lions in the HSTT Study 
Area for integrated training involving two primary missions areas: To 
find objects such as inert mine shapes, and to detect swimmers or other 
intruders around Navy facilities such as piers. When deployed, the 
animals are part of what the Navy refers to as marine mammal systems. 
These systems include one or more motorized small boats, several crew 
members, and a trained marine mammal. Each trained animal is deployed 
under behavioral control to find the intruding swimmer or submerged 
object.

Naval Special Warfare

    The mission of naval special warfare is to conduct unconventional 
warfare, direct action, combat terrorism, special reconnaissance, 
information warfare, security assistance, counter-drug operations, and 
recovery of personnel from hostile situations. Naval special warfare 
operations are highly specialized and require continual and intense 
training. Naval special warfare units are required to utilize a 
combination of specialized training, equipment, and tactics, including 
insertion and extraction operations using parachutes, submerged 
vehicles, rubber boats, and helicopters; boat-to-shore and boat-to-boat 
gunnery; underwater demolition training; reconnaissance; and small arms 
training.

Overview of Testing Activities

    The Navy researches, develops, tests, and evaluates new platforms, 
systems, and technologies. Testing activities may occur independently 
of or in conjunction with training activities. Many testing activities 
are conducted similarly to Navy training activities and are also 
categorized under one of the primary mission areas. Other testing 
activities are unique and are described within their specific testing 
categories. The Navy determined that stressors used during the 
following testing activities are most likely to result in impacts on 
marine mammals:
     Naval Air Systems Command (NAVAIR) Testing
    [cir] Anti-surface warfare testing (underwater detonations)
    [cir] Anti-submarine warfare testing (active sonar, underwater 
detonations)
    [cir] Mine warfare testing (active sonar, underwater detonations)
     Naval Sea Systems command (NAVSEA) Testing
    [cir] New ship construction (active sonar, underwater detonations)
    [cir] Life cycle activities (active sonar, underwater detonations)
    [cir] Anti-surface warfare/anti-submarine warfare testing (active 
sonar, underwater detonations)
    [cir] Mine warfare testing (active sonar, underwater detonations)
    [cir] Ship protection systems and swimmer defense testing (active 
sonar, airguns)
    [cir] Unmanned vehicle testing (active sonar)
    [cir] Other testing (active sonar)
     Space and Naval Warfare Systems Commands (SPAWAR) Testing
    [cir] SPAWAR research, development, test, and evaluation (active 
sonar)
     Office of Naval Research (ONR) and Naval Research 
Laboratory (NRL) Testing
    [cir] ONR/NRL research, development, test, and evaluation (active 
sonar)
    Other Navy testing activities do not involve stressors that could 
result in marine mammal harassment. Therefore, these activities are not 
discussed further.

Naval Air Systems Command Testing (NAVAIR)

    NAVAIR events include testing of new aircraft platforms, weapons, 
and systems before delivery to the fleet for training activities. 
NAVAIR also conducts lot acceptance testing of weapons and systems, 
such as sonobuoys. In general, NAVAIR conducts its testing activities 
the same way the fleet conducts its training activities. However, 
NAVAIR testing activities may occur in different locations than 
equivalent fleet training activities and testing of a particular system 
may differ slightly from the way the fleet trains with the same system.
    Anti-surface Warfare Testing--Anti-surface warfare testing includes 
air-to-surface gunnery, missile, and rocket exercises. Testing is 
required to ensure the equipment is fully functional for defense from 
surface threats. Testing may be conducted on new guns or run rounds, 
missiles, rockets, and aircraft, and also in support of scientific 
research to assess new and emerging technologies. Testing events are 
often integrated into training activities and in most cases the systems 
are used in the same manner in which they are used for fleet training 
activities.
    Anti-submarine Warfare Testing--Anti-submarine warfare testing 
addresses basic skills such as detection and classification of 
submarines, distinguishing between sounds made by enemy submarines and 
those of friendly submarines, ships, and marine life. More advanced, 
integrated anti-submarine warfare testing is conducted in coordinated, 
at-sea training events involving submarines, ships, and aircraft. This 
testing integrates the full spectrum of anti-submarine warfare from 
detecting and tracking a submarine to attacking a target using various 
torpedoes and weapons.
    Mine Warfare Testing--Mine warfare testing includes activities in 
which aircraft detection systems are used to search for and record the 
location of mines for subsequent neutralization. Mine neutralization 
tests evaluate a system's effectiveness at intentionally detonating or 
otherwise disabling the mine. Different mine neutralization systems are 
designed to neutralize mines either at the sea surface or deployed 
deeper within the water column. All components of these systems are 
tested in the at-sea environment to ensure they meet mission 
requirements.

Naval Sea Systems Command Testing (NAVSEA)

    NAVSEA testing activities are aligned with its mission of new ship 
construction, life cycle support, and other weapon systems development 
and testing.
    New Ship Construction Activities--Ship construction activities 
include pierside testing of ship systems, tests to determine how the 
ship performs at sea (sea trials), and developmental and operational 
test and evaluation programs for new technologies and systems. Pierside 
and at-sea testing of systems aboard a ship may include sonar, acoustic 
countermeasures, radars, and radio equipment. During sea trials, each 
new ship propulsion engine is operated at full power and subjected to 
high-speed runs and steering tests. At-sea test firing of shipboard 
weapon systems, including guns, torpedoes, and missiles, are also 
conducted.
    Life Cycle Activities--Testing activities are conducted throughout 
the life of a Navy ship to verify performance and mission capabilities. 
Sonar system testing occurs pierside during maintenance, repair, and 
overhaul availabilities, and at sea immediately following most major 
overhaul periods. A Combat System Ship Qualification

[[Page 6981]]

Trial is conducted for new ships and for ships that have undergone 
modification or overhaul of their combat systems. Radar cross signature 
testing of surface ships is conducted on new vessels and periodically 
throughout a ship's life to measure how detectable the ship is by 
radar. Electromagnetic measurements of off-board electromagnetic 
signature are also conducted for submarines, ships, and surface craft 
periodically.
    Other Weapon Systems Development and Testing--Numerous test 
activities and technical evaluations, in support of NAVSEA's systems 
development mission, often occur with fleet activities within the Study 
Area. Tests within this category include, but are not limited to, anti-
surface, anti-submarine, and mine warfare, using torpedoes, sonobuoys, 
and mine detection and neutralization systems.

Space and Naval Warfare Systems Command Testing (SPAWAR)

    The mission of SPAWAR is to acquire, develop, deliver, and sustain 
decision superiority for the warfighter at the right time and for the 
right cost. SPAWAR Systems Center Pacific is the research and 
development part of SPAWAR focused on developing and transitioning 
technologies in the area of command, control, communications, 
computers, intelligence, surveillance, and reconnaissance. SPAWAR 
Systems Center Pacific conducts research, development, test, and 
evaluation projects to support emerging technologies for intelligence, 
surveillance, and reconnaissance; anti-terrorism and force protection; 
mine countermeasures; anti-submarine warfare; oceanographic research; 
remote sensing; and communications. These activities include, but are 
not limited to, the testing of unmanned undersea and surface vehicles, 
a wide variety of intelligence, surveillance, and reconnaissance sensor 
systems, underwater surveillance technologies, and underwater 
communications.

Office of Naval Research and Naval Research Laboratory Testing (ONR and 
NRL)

    As the Navy's science and technology provider, ONR and NRL provide 
technology solutions for Navy and Marine Corps needs. ONR's mission is 
to plan, foster, and encourage scientific research in recognition of 
its paramount importance as related to the maintenance of future naval 
power, and the preservation of national security. Further, ONR manages 
the Navy's basic, applied, and advanced research to foster transition 
from science and technology to higher levels of research, development, 
test, and evaluation. The Ocean Battlespace Sensing Department explores 
science and technology in the areas of oceanographic and meteorological 
observations, modeling, and prediction in the battlespace environment; 
submarine detection and classification (anti-submarine warfare); and 
mine warfare applications for detecting and neutralizing mines in both 
the ocean and littoral environment. ONR events include research, 
development, test, and evaluation activities; surface processes 
acoustic communications experiments; shallow water acoustic 
communications experiments; sediment acoustics experiments; shallow 
water acoustic propagation experiments; and long range acoustic 
propagation experiments.

Sonar, Ordnance, Targets, and Other Systems

    The Navy uses a variety of sensors, platforms, weapons, and other 
devices to meet its mission. Training and testing with these systems 
may introduce acoustic (sound) energy into the environment. This 
section describes and organizes sonar systems, ordnance, munitions, 
targets, and other systems to facilitate understanding of the 
activities in which these systems are used. Underwater sound is 
described as one of two types for the purposes of the Navy's 
application: impulsive and non-impulsive. Underwater detonations of 
explosives and other percussive events are impulsive sounds. Sonar and 
similar sound producing systems are categorized as non-impulsive sound 
sources.
    Sonar and Other Non-impulsive Sources--Modern sonar technology 
includes a variety of sonar sensor and processing systems. The simplest 
active sonar emits sound waves, or ``pings,'' sent out in multiple 
directions and the sound waves then reflect off of the target object in 
multiple directions. The sonar source calculates the time it takes for 
the reflected sound waves to return; this calculation determines the 
distance to the target object. More sophisticated active sonar systems 
emit a ping and then rapidly scan or listen to the sound waves in a 
specific area. This provides both distance to the target and 
directional information. Even more advanced sonar systems use multiple 
receivers to listen to echoes from several directions simultaneously 
and provide efficient detection of both direction and distance. The 
Navy rarely uses active sonar continuously throughout activities. When 
sonar is in use, the pings occur at intervals, referred to as a duty 
cycle, and the signals themselves are very short in duration. For 
example, sonar that emits a 1-second ping every 10 seconds has a 10-
percent duty cycle. The Navy utilizes sonar systems and other acoustic 
sensors in support of a variety of mission requirements. Primary uses 
include the detection of and defense against submarines (anti-submarine 
warfare) and mines (mine warfare); safe navigation and effective 
communications; use of unmanned undersea vehicles; and oceanographic 
surveys.
    Ordnance and Munitions--Most ordnance and munitions used during 
training and testing events fall into three basic categories: 
Projectiles (such as gun rounds), missiles (including rockets), and 
bombs. Ordnance can be further defined by their net explosive weight, 
which considers the type and quantity of the explosive substance 
without the packaging, casings, bullets, etc. Net explosive weight 
(NEW) is the trinitrotoluene (TNT) equivalent of energetic material, 
which is the standard measure of strength of bombs and other 
explosives. For example, a 12.7-centimeter(cm) shell fired from a Navy 
gun is analyzed at about 9.5 pounds (lb) (4.3 kilograms (kg)) of NEW. 
The Navy also uses non-explosive ordnance in place of high explosive 
ordnance in many training and testing events. Non-explosive ordnance 
munitions look and perform similarly to high explosive ordnance, but 
lack the main explosive charge.
    Defense Countermeasures--Naval forces depend on effective defensive 
countermeasures to protect themselves against missile and torpedo 
attack. Defensive countermeasures are devices designed to confuse, 
distract, and confound precision guided munitions. Defensive 
countermeasures analyzed in this LOA application include acoustic 
countermeasures, which are used by surface ships and submarines to 
defend against torpedo attack. Acoustic countermeasures are either 
released from ships and submarines, or towed at a distance behind the 
ship.
    Mine Warfare Systems--The Navy divides mine warfare systems into 
two categories: mine detection and mine neutralization. Mine detection 
systems are used to locate, classify, and map suspected mines, on the 
surface, in the water column, or on the sea floor. The Navy analyzed 
the following mine detection systems for potential impacts to marine 
mammals:
     Towed or hull-mounted mine detection systems. These 
detection systems use acoustic and laser or video sensors to locate and 
classify suspect mines. Fixed and rotary wing platforms, ships, and 
unmanned vehicles are used

[[Page 6982]]

for towed systems, which can rapidly assess large areas.
     Unmanned/remotely operated vehicles. These vehicles use 
acoustic and video or lasers to locate and classify mines and provide 
unique capabilities in nearshore littoral areas, surf zones, ports, and 
channels.
     Marine mammal systems. The Navy deploys trained Atlantic 
bottlenose dolphins (Tursiops truncatus) and California sea lions 
(Zalopus californianus) for integrated training involving two primary 
mission areas: to find objects such as inert mine shapes, and to detect 
swimmers or other intruders around Navy facilities such as piers. These 
systems also include one or more motorized small boats and several crew 
members for each trained marine mammal. When not engaged in training, 
Navy marine mammals are housed in temporary enclosures either on land 
or aboard ships.
    Mine Neutralization Systems--Mine neutralization systems disrupt, 
disable, or detonate mines to clear ports and shipping lanes, as well 
as littoral, surf, and beach areas in support of naval amphibious 
operations. The Navy analyzed the following mine neutralization systems 
for potential impacts to marine mammals:
     Towed influence mine sweep systems. These systems use 
towed equipment that mimic a particular ship's magnetic and acoustic 
signature triggering the mine and causing it to explode.
     Unmanned/remotely operated mine neutralization systems. 
Surface ships and helicopters operate these systems, which place 
explosive charges near or directly against mines to destroy the mine.
     Airborne projectile-based mine clearance systems. These 
systems neutralize mines by firing a small or medium-caliber non-
explosive, supercavitating projectile from a hovering helicopter.
     Diver emplaced explosive charges. Operating from small 
craft, divers put explosive charges near or on mines to destroy the 
mine or disrupt its ability to function.

Classification of Non-Impulsive and Impulsive Sources Analyzed

    In order to better organize and facilitate the analysis of about 
300 sources of underwater non-impulsive sound or impulsive energy, the 
Navy developed a series of source classifications, or source bins. This 
method of analysis provides the following benefits:
     Allows for new sources to be covered under existing 
authorizations, as long as those sources fall within the parameters of 
a ``bin;''
     Simplifies the data collection and reporting requirements 
anticipated under the MMPA;
     Ensures a conservative approach to all impact analysis 
because all sources in a single bin are modeled as the loudest source 
(e.g., lowest frequency, highest source level, longest duty cycle, or 
largest net explosive weight within that bin);
     Allows analysis to be conducted more efficiently, without 
compromising the results;
     Provides a framework to support the reallocation of source 
usage (hours/explosives) between different source bins, as long as the 
total number and severity of marine mammal 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.
    A description of each source classification is provided in Tables 
1-3. Non-impulsive sources are grouped into bins based on the 
frequency, source level when warranted, and how the source would be 
used. Impulsive bins are based on the net explosive weight of the 
munitions or explosive devices. The following factors further describe 
how non-impulsive sources are divided:
     Frequency of the non-impulsive source:
    [cir] Low-frequency sources operate below 1 kilohertz (kHz)
    [cir] Mid-frequency sources operate at or 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, but below 200 
kHz
     Source level of the non-impulsive source:
    [cir] Greater than 160 decibels (dB), but less than 180 dB
    [cir] Equal to 180 dB and up to 200 dB
    [cir] Greater than 200 dB
    How a sensor is used determines how the sensor's acoustic emissions 
are analyzed. Factors to consider include pulse length (time source is 
on); beam pattern (whether sound is emitted as a narrow, focused beam, 
or, as with most explosives, in all directions); and duty cycle (how 
often a transmission occurs in a given time period during an event).
    There are also non-impulsive sources with characteristics that are 
not anticipated to result in takes of marine mammals. These sources 
have low source levels, narrow beam widths, downward directed 
transmission, short pulse lengths, frequencies beyond known hearing 
ranges of marine mammals, or some combination of these factors. These 
sources were not modeled by the Navy, but are qualitatively analyzed in 
Table 1-4 of the LOA application and the HSTT DEIS/OEIS.

                         Table 1--Impulsive Training and Testing Source Classes Analyzed
----------------------------------------------------------------------------------------------------------------
             Source class                 Representative munitions            Net explosive weight (lbs)
----------------------------------------------------------------------------------------------------------------
E1...................................  Medium-caliber projectiles...  0.1-0.25 (45.4-113.4 g)
E2...................................  Medium-caliber projectiles...  0.26-0.5 (117.9-226.8 g)
E3...................................  Large-caliber projectiles....  >0.5-2.5 (>226.8 g-1.1 kg)
E4...................................  Improved Extended Echo         >2.5-5.0 (1.1-2.3 kg)
                                        Ranging Sonobuoy.
E5...................................  5 in. (12.7 cm) projectiles..  >5-10 (>2.3-4.5 kg)
E6...................................  15 lb. (6.8 kg) shaped charge  >10-20 (>4.5-9.1 kg)
E7...................................  40 lb. (18.1 kg) demo block/   >20-60 (>9.1-27.2 kg)
                                        shaped charge.
E8...................................  250 lb. (113.4 kg) bomb......  >60-100 (>27.2-45.4 kg)
E9...................................  500 lb. (226.8 kg) bomb......  >100-250 (>45.4-113.4 kg)
E10..................................  1,000 lb. (453.6 kg) bomb....  >250-500 (>113.4-226.8 kg)
E11..................................  650 lb. (294.8 kg) mine......  >500-650 (>226.8-294.8 kg)
E12..................................  2,000 lb. (907.2 kg) bomb....  >650-1,000 (>294.8-453.6 kg)
E13..................................  1,200 lb. (544.3 kg) HBX       >1,000-1,740 (>453.6-789.3 kg)
                                        charge.
----------------------------------------------------------------------------------------------------------------


[[Page 6983]]


         Table 2--Non-Impulsive Training Source Classes Analyzed
------------------------------------------------------------------------
                                   Source
     Source class category         class             Description
------------------------------------------------------------------------
Mid-Frequency (MF): Tactical           MF1  Active hull-mounted surface
 and non-tactical sources that               ship sonar (e.g., AN/SQS-
 produce mid-frequency (1 to 10              53C and AN/SQS-60).
 kHz) signals.
                                      MF1K  Kingfisher object avoidance
                                             mode associated with MF1
                                             sonar.
                                       MF2  Active hull-mounted surface
                                             ship sonar (e.g., AN/SQS-
                                             56).
                                      MF2K  Kingfisher mode associated
                                             with MF2 sonar.
                                       MF3  Active hull-mounted
                                             submarine sonar (e.g., AN/
                                             BQQ-10).
                                       MF4  Active helicopter-deployed
                                             dipping sonar (e.g., AN/AQS-
                                             22 and AN/AQS-13).
                                       MF5  Active acoustic sonobuoys
                                             (e.g., AN/SSQ-62 DICASS).
                                       MF6  Active underwater sound
                                             signal devices (e.g., MK-
                                             84).
                                      MF11  Hull-mounted surface ship
                                             sonar with an active duty
                                             cycle greater than 80%.
                                      MF12  High duty cycle--variable
                                             depth sonar.
High-Frequency (HF) and Very           HF1  Active hull-mounted
 High-Frequency (VHF): Tactical        HF4   submarine sonar (e.g., AN/
 and non-tactical sources that               BQQ-15).
 produce high-frequency                     Active mine detection,
 (greater than 10 kHz but less               classification, and
 than 200 kHz) signals.                      neutralization sonar (e.g.,
                                             AN/SQS-20).
Anti-Submarine Warfare (ASW):         ASW1  MF active Deep Water Active
 Tactical sources such as             ASW2   Distributed System (DWADS).
 active sonobuoys and acoustic              MF active Multistatic Active
 countermeasures systems used                Coherent (MAC) sonobuoy
 during ASW training activities.             (e.g., AN/SSQ-125).
                                      ASW3  MF active towed active
                                             acoustic countermeasure
                                             systems (e.g., AN/SLQ-25
                                             NIXIE).
                                      ASW4  MF active expendable active
                                             acoustic device
                                             countermeasures (e.g., MK-
                                             3).
Torpedoes (TORP): Source             TORP1  HF active lightweight
 classes associated with active              torpedo sonar (e.g., MK-46,
 acoustic signals produced by                MK-54, or Anti-Torpedo
 torpedoes.                                  Torpedo).
                                     TORP2  HF active heavyweight
                                             torpedo sonar (e.g., MK-
                                             48).
------------------------------------------------------------------------


         Table 3--Non-Impulsive Testing Source Classes Analyzed
------------------------------------------------------------------------
                                   Source
     Source class category         class             Description
------------------------------------------------------------------------
Low-Frequency (LF): Sources            LF4  Low-frequency sources equal
 that produce low-frequency                  to 180 dB and up to 200 dB.
 (less than 1 kilohertz [kHz])
 signals.
                                       LF5  Low-frequency sources less
                                             than 180 dB.
                                       LF6  Low-frequency sonar
                                             currently in development
                                             (e.g., anti-submarine
                                             warfare sonar associated
                                             with the Littoral Combat
                                             Ship).
Mid-Frequency (MF): Tactical           MF1  Hull-mounted surface ship
 and non-tactical sources that        MF1K   sonar (e.g., AN/SQS-53C and
 produce mid-frequency (1 to 10              AN/SQS-60).
 kHz) signals.                              Kingfisher mode associated
                                             with MF1 sonar (Sound
                                             Navigation and Ranging).
                                       MF2  Hull-mounted surface ship
                                             sonar (e.g., AN/SQS-56).
                                       MF3  Hull-mounted submarine sonar
                                             (e.g., AN/BQQ-10).
                                       MF4  Helicopter-deployed dipping
                                             sonar (e.g., AN/AQS-22 and
                                             AN/AQS-13).
                                       MF5  Active acoustic sonobuoys
                                             (e.g., DICASS).
                                       MF6  Active underwater sound
                                             signal devices (e.g., MK-
                                             84).
                                       MF8  Active sources (greater than
                                             200 dB).
                                       MF9  Active sources (equal to 180
                                             dB and up to 200 dB).
                                      MF10  Active sources (greater than
                                             160 dB, but less than 180
                                             dB) not otherwise binned.
                                      MF12  High duty cycle--variable
                                             depth sonar.
High-Frequency (HF) and Very           HF1  Hull-mounted submarine sonar
 High-Frequency (VHF): Tactical        HF3   (e.g., AN/BQQ-10).
 and non-tactical sources that         HF4  Hull-mounted submarine sonar
 produce high-frequency                      (classified).
 (greater than 10 kHz but less              Mine detection,
 than 200 kHz) signals.                      classification, and
                                             neutralization sonar (e.g.,
                                             AN/SQS-20).
                                       HF5  Active sources (greater than
                                             200 dB).
                                       HF6  Active sources (equal to 180
                                             dB and up to 200 dB).
Anti-Submarine Warfare (ASW):         ASW1  Mid-frequency Deep Water
 Tactical sources such as                    Active Distributed System
 active sonobuoys and acoustic               (DWADS).
 countermeasures systems used
 during the conduct of anti-
 submarine warfare testing
 activities.
                                      ASW2  Mid-frequency Multistatic
                                     ASW2H   Active Coherent sonobuoy
                                             (e.g., AN/SSQ-125).
                                            Mid-frequency sonobuoy
                                             (e.g., high duty cycle)--
                                             Sources that are analyzed
                                             by hours.
                                      ASW3  Mid-frequency towed active
                                             acoustic countermeasure
                                             systems (e.g., AN/SLQ-25).
                                      ASW4  Mid-frequency expendable
                                             active acoustic device
                                             countermeasures (e.g., MK-
                                             3).

[[Page 6984]]

 
Torpedoes (TORP): Source             TORP1  Lightweight torpedo (e.g.,
 classes associated with the                 MK-46, MK-54, or Surface
 active acoustic signals                     Ship Defense System).
 produced by torpedoes.
                                     TORP2  Heavyweight torpedo (e.g.,
                                             MK-48).
Acoustic Modems (M): Systems            M3  Mid-frequency acoustic
 used to transmit data                       modems (greater than 190
 acoustically through water.                 dB).
Swimmer Detection Sonar (SD):      SD1-SD2  High-frequency sources with
 Systems used to detect divers               short pulse lengths, used
 and submerged swimmers.                     for the detection of
                                             swimmers and other objects
                                             for the purpose of port
                                             security.
Airguns (AG): Underwater                AG  Up to 60 cubic inch airguns
 airguns are used during                     (e.g., Sercel Mini-G).
 swimmer defense and diver
 deterrent training and testing
 activities.
Synthetic Aperture Sonar (SAS):       SAS1  MF SAS systems.
 Sonar in which active acoustic       SAS2  HF SAS systems.
 signals are post-processed to        SAS3  VHF SAS systems.
 form high-resolution images of
 the seafloor.
------------------------------------------------------------------------

 Proposed Action

    The Navy proposes to continue conducting training and testing 
activities within the HSTT Study Area. The Navy has been conducting 
military readiness training and testing activities in the HSTT Study 
Area since the 1940s. Recently, these activities were analyzed in three 
separate EISs completed between 2008 and 2011; the Hawaii Range Complex 
(HRC) EIS/OEIS (U.S. Department of the Navy 2008a), the SOCAL Range 
Complex EIS/OEIS (U.S. Department of the Navy 2008b), and the Silver 
Strand Training Complex (SSTC) EIS (U.S. Department of the Navy 2011a). 
These documents, among others, and their associated MMPA regulations 
and authorizations, describe the baseline of training and testing 
activities currently conducted in the Study Area.
    The tempo and types of training and testing activities have 
fluctuated due to changing requirements; the introduction of new 
technologies; the dynamic nature of international events; advances in 
warfighting doctrine and procedures; and changes in basing locations 
for ships, aircraft, and personnel (force structure changes). Such 
developments have influenced the frequency, duration, intensity, and 
location of required training and testing.

Training

    The Navy proposes to conduct training activities in the Study Area 
as described in Tables 4 and 5. Detailed information about each 
proposed activity (stressor, training event, description, sound source, 
duration, and geographic location) can be found in Appendix A of the 
HSTT DEIS/OEIS. NMFS used the detailed information in Appendix A of the 
HSTT DEIS/OEIS to analyze the potential impacts to marine mammals. 
Table 4 describes the annual number of impulsive source detonations 
during testing activities within the HSTT Study Area, and Table 5 
describes the annual number of hours or items of non-impulsive sources 
used during training within the HSTT Study Area. The Navy's proposed 
action is an adjustment to existing baseline training activities to 
accommodate the following:
     Force structure changes including the relocation of ships, 
aircraft, and personnel;
     Planned new aircraft platforms, new vessel classes, and 
new weapons systems;
     Ongoing training activities that were not addressed in 
previous documentation; and
     New range capabilities, such as hydrophone modifications, 
upgrades, and replacement at instrumented Navy underwater tracking 
ranges.

 Table 4--Proposed Annual Number of Impulsive Source Detonations During
                     Training in the HSTT Study Area
------------------------------------------------------------------------
                                                            Annual in-
                                   Net explosive weight        water
        Explosive class                   (NEW)             detonations
                                                            (training)
------------------------------------------------------------------------
E1.............................  (0.1 lb.-0.25 lb.).....          19,840
E2.............................  (0.26 lb.-0.5 lb.).....           1,044
E3.............................  (0.6 lb.-2.5 lb.)......           3,020
E4.............................  (>2.5 lb.-5 lb.).......             668
E5.............................  (>5 lb.-10 lb.)........           8,154
E6.............................  (>10 lb.-20 lb.).......             538
E7.............................  (>20 lb.-60 lb.).......             407
E8.............................  (>60 lb.-100 lb.)......              64
E9.............................  (>100 lb.-250 lb.).....              16
E10............................  (>250 lb.-500 lb.).....              19
E11............................  (>500 lb.-650 lb.).....               8
E12............................  (>650 lb.-1000 lb.)....             224
E13............................  (>1000 lb.-1,740 lb.)..               9
------------------------------------------------------------------------


[[Page 6985]]


  Table 5--Annual Hours and Items of Non-Impulsive Sources Used During
                   Training Within the HSTT Study Area
------------------------------------------------------------------------
                                      Source
       Source class category          class            Annual use
------------------------------------------------------------------------
Mid-Frequency (MF) Active sources         MF1  11,588 hours.
 from 1 to 10 kHz.
                                         MF1K  88 hours.
                                          MF2  3,060 hours.
                                         MF2K  34 hours.
                                          MF3  2,336 hours.
                                          MF4  888 hours.
                                          MF5  13,718 items.
                                         MF11  1,120 hours.
                                         MF12  1,094 hours.
High-Frequency (HF) and Very High-        HF1  1,754 hours.
 Frequency (VHF) tactical and non-
 tactical sources that produce
 signals greater than 10kHz but
 less than 200 kHz.
                                          HF4  4,848 hours.
Anti-Submarine Warfare (ASW)......       ASW1  224 hours.
Active ASW sources................       ASW2  1,800 items.
                                         ASW3  16,561 hours.
                                         ASW4  1,540 items.
Torpedoes (TORP)..................      TORP1  170 items.
Active torpedo sonar..............      TORP2  400 items.
------------------------------------------------------------------------

Testing

    The Navy's proposed testing activities are described in Tables 6 
and 7. Detailed information about each proposed activity (stressor, 
testing event, description, sound source, duration, and geographic 
location) can be found in Appendix A of the HSTT DEIS/OEIS. NMFS used 
the detailed information in Appendix A of the HSTT DEIS/OEIS to analyze 
the potential impacts from testing activities on marine mammals. Table 
6 describes the annual number of impulsive source detonations during 
testing activities within the HSTT Study Area, and Table 7 describes 
the annual number of hours or items of non-impulsive sources used 
during testing within the HSTT Study Area.

 Table 6--Proposed Annual Number of Impulsive Source Detonations During
              Testing Activities Within the HSTT Study Area
------------------------------------------------------------------------
                                                            Annual in-
                                   Net explosive weight        water
        Explosive class                   (NEW)             detonations
                                                             (testing)
------------------------------------------------------------------------
E1.............................  (0.1 lb.-0.25 lb.).....          14,501
E2.............................  (0.26 lb.-0.5 lb.).....               0
E3.............................  (0.6 lb.-2.5 lb.)......           2,990
E4.............................  (>2.5 lb.-5 lb.).......             753
E5.............................  (>5 lb.-10 lb.)........             202
E6.............................  (>10 lb.-20 lb.).......              37
E7.............................  (>20 lb.-60 lb.).......              21
E8.............................  (>60 lb.-100 lb.)......              12
E9.............................  (>100 lb.-250 lb.).....               0
E10............................  (>250 lb.-500 lb.).....              31
E11............................  (>500 lb.-650 lb.).....              14
E12............................  (>650 lb.-1000 lb.)....               0
E13............................  (>1000 lb.-1,740 lb.)..               0
------------------------------------------------------------------------


  Table 7--Annual Hours and Items of Non-Impulsive Sources Used During
                   Testing Within the HSTT Study Area
------------------------------------------------------------------------
                                      Source
       Source class category          class            Annual use
------------------------------------------------------------------------
Low-Frequency (LF) Sources that           LF4  52 hours.
 produce signals less than 1 kHz.
                                          LF5  2,160 hours.
                                          LF6  192 hours.
Mid-Frequency (MF) Tactical and           MF1  180 hours.
 non-tactical sources that produce
 signals from 1 to 10 kHz.
                                         MF1K  18 hours.
                                          MF2  84 hours.
                                          MF3  392 hours.
                                          MF4  693 hours.
                                          MF5  5,024 items.

[[Page 6986]]

 
                                          MF6  540 items.
                                          MF8  2 hours.
                                          MF9  3,039 hours.
                                         MF10  35 hours.
                                         MF12  336 hours.
High-Frequency (HF) and Very High-        HF1  1,025 hours.
 Frequency (VHF): Tactical and non-
 tactical sources that produce
 signals greater than 10kHz but
 less than 200kHz.
                                          HF3  273 hours.
                                          HF4  1,336 hours.
                                          HF5  1,094 hours.
                                          HF6  3,460 hours.
Anti-Submarine Warfare (ASW)             ASW1  224 hours.
 Tactical sources used during anti-
 submarine warfare training and
 testing activities.
                                         ASW2  2,260 items.
                                        ASW2H  255 hours.
                                         ASW3  1,278 hours.
                                         ASW4  477 items.
Torpedoes (TORP) Source classes         TORP1  701 items.
 associated with active acoustic
 signals produced by torpedoes.
                                        TORP2  732 items.
Acoustic Modems (M) Transmit data          M3  4,995 hours.
 acoustically through the water.
Swimmer Detection Sonar (SD) Used         SD1  38 hours.
 to detect divers and submerged
 swimmers.
Airguns (AG) Used during swimmer           AG  5 uses.
 defense and diver deterrent
 training and testing activities.
Synthetic Aperture Sonar (SAS):          SAS1  2,700 hours.
 Sonar in which active acoustic
 signals are post-processed to
 form high-resolution images of
 the seafloor.
                                         SAS2  4,956 hours.
                                         SAS3  3,360 hours.
------------------------------------------------------------------------

Vessels

    Vessels used as part of the proposed action include ships, 
submarines, boats, and Unmanned Undersea Vehicles (UUVs) ranging in 
size from small, 5-m Rigid Hull Inflatable Boats to 333-m long aircraft 
carriers. Representative Navy vessel types, lengths, and speeds used in 
both training and testing activities are shown in Table 8. While these 
speeds are representative, some vessels operate outside of these speeds 
due to unique training or safety requirements for a given event. 
Examples include increased speeds needed for flight operations, full 
speed runs to test engineering equipment, time critical positioning 
needs, etc. Examples of decreased speeds include speeds less than 5 
knots or completely stopped for launching small boats, certain tactical 
maneuvers, target launch or retrievals, UUVs etc.
    The number of Navy vessels in the HSTT Study Area varies based on 
training and testing schedules. Most activities include either one or 
two vessels, with an average of one vessel per activity, and last from 
a few hours up to two weeks. Multiple ships, however, can be involved 
with major training events. Vessel movement and the use of in-water 
devices as part of the proposed action would be concentrated in 
portions of the Study Area within SOCAL, naval installations at San 
Diego and Pearl Harbor, and on instrumented underwater ranges. Surface 
and sub-surface vessel operations in the Study Area may result in 
marine mammal strikes.

 Table 8--Typical Navy Boat and Vessel Types With Length Greater Than 18
                 Meters Used Within the HSTT Study Area
------------------------------------------------------------------------
                                      Example(s)
                                  (specifications in
                                meters (m) for length,       Typical
      Vessel type (>18 m)        metric tons (mt) for    operating speed
                                  mass, and knots for        (knots)
                                        speed)
------------------------------------------------------------------------
Aircraft Carrier..............  Aircraft Carrier (CVN)  10 to 15.
                                 length: 333 m beam:
                                 41 m draft: 12 m
                                 displacement: 81,284
                                 mt max. speed: 30+
                                 knots.
Surface Combatants............  Cruiser (CG) length:    10 to 15.
                                 173 m beam: 17 m
                                 draft: 10 m
                                 displacement: 9,754
                                 mt max. speed: 30+
                                 knots.
                                Destroyer (DDG)
                                 length: 155 m beam:
                                 18 m draft: 9 m
                                 displacement: 9,648
                                 mt max. speed: 30+
                                 knots.
                                Frigate (FFG) length:
                                 136 m beam: 14 m
                                 draft: 7 m
                                 displacement: 4,166
                                 mt max. speed: 30+
                                 knots.
                                Littoral Combat Ship
                                 (LCS) length: 115 m
                                 beam: 18 m draft: 4 m
                                 displacement: 3,000
                                 mt max. speed: 40+
                                 knots.

[[Page 6987]]

 
Amphibious Warfare Ships......  Amphibious Assault      10 to 15.
                                 Ship (LHA, LHD)
                                 length: 253 m beam:
                                 32 m draft: 8 m
                                 displacement: 42,442
                                 mt max. speed: 20+
                                 knots.
                                Amphibious Transport
                                 Dock (LPD) length:
                                 208 m beam: 32 m
                                 draft: 7 m
                                 displacement: 25,997
                                 mt max. speed: 20+
                                 knots.
                                Dock Landing Ship
                                 (LSD) length: 186 m
                                 beam: 26 m draft: 6 m
                                 displacement: 16,976
                                 mt max. speed: 20+
                                 knots.
Mine Warship Ship.............  Mine Countermeasures    5 to 8.
                                 Ship (MCM) length: 68
                                 m beam: 12 m draft: 4
                                 m displacement: 1,333
                                 max. speed: 14 knots.
Submarines....................  Attack Submarine (SSN)  8 to 13.
                                 length: 115 m beam:
                                 12 m draft: 9 m
                                 displacement: 12,353
                                 mt max. speed: 20+
                                 knots.
                                Guided Missile
                                 Submarine (SSGN)
                                 length: 171 m beam:
                                 13 m draft: 12 m
                                 displacement: 19,000
                                 mt max. speed: 20+
                                 knots.
Combat Logistics Force Ships*.  Fast Combat Support     8 to 12.
                                 Ship (T-AOE) length:
                                 230 m beam: 33 m
                                 draft: 12 m
                                 displacement: 49,583
                                 max. speed: 25 knots.
                                Dry Cargo/Ammunition
                                 Ship (T-AKE) length:
                                 210 m beam: 32 m
                                 draft: 9 m
                                 displacement: 41,658
                                 mt max speed: 20
                                 knots.
                                Fleet Replenishment
                                 Oilers (T-AO) length:
                                 206 m beam: 30 m
                                 draft: 11
                                 displacement: 42,674
                                 mt max. speed: 20
                                 knots.
                                Fleet Ocean Tugs (T-
                                 ATF) length: 69 m
                                 beam: 13 m draft: 5 m
                                 displacement: 2,297
                                 max. speed: 14 knots.
Support Craft/Other...........  Landing Craft, Utility  3 to 5.
                                 (LCU) length: 41m
                                 beam: 9 m draft: 2 m
                                 displacement: 381 mt
                                 max. speed: 11 knots.
                                Landing Craft,
                                 Mechanized (LCM)
                                 length: 23 m beam: 6
                                 m draft: 1 m
                                 displacement: 107 mt
                                 max. speed: 11 knots.
Support Craft/Other             MK V Special            Variable.
 Specialized High Speed.         Operations Craft
                                 length: 25 m beam: 5
                                 m displacement: 52 mt
                                 max. speed: 50 knots.
------------------------------------------------------------------------
* CLF vessels are not homeported in Pearl Harbor or San Diego, but are
  frequently used for various fleet support and training support events
  in the HSTT Study Area.

Duration and Location

    Training and testing activities would be conducted in the HSTT 
Study Area from January 2014 through January 2019. The HSTT Study Area 
is comprised of established operating and warning areas across the 
north-central Pacific Ocean, from Southern California to Hawaii and the 
International Date Line. The defined Study Area has expanded beyond the 
areas included in previous Navy authorizations to include transit 
routes and pierside locations. This expansion is not an increase in the 
Navy's training and testing area, but rather an increase in the area to 
be analyzed (i.e., not previously analyzed) under an incidental take 
authorization in support of the HSTT EIS/OEIS. The Study Area includes 
three existing range complexes: the Hawaii Range Complex (HRC), the 
Southern California (SOCAL) Range Complex, and the Silver Strand 
Training Complex (SSTC). Each range complex is an organized and 
designated set of specifically bounded geographic areas, which includes 
a water component (above and below the surface), airspace, and 
sometimes a land component. Operating areas (OPAREAs) and special use 
airspace are established within each range complex. These designations 
are further described in Chapter 2 of the Navy's LOA application. In 
addition to Navy range complexes, the Study Area includes Navy pierside 
locations where sonar maintenance and testing activities occur (San 
Diego Bay, Pearl Harbor) and transit corridors on the high seas where 
training and sonar testing may occur during vessel transit.
    Hawaii Range Complex (HRC)--The HRC geographically encompasses 
ocean areas located around the Hawaiian Islands chain. The largest 
component of the HRC is the temporary operating area, which extends 
north and west from the island of Kauai and totals over 2 million 
square nautical miles (nm\2\) of air and sea space. This area is used 
for Navy ship transit throughout the year and for missile defense 
testing activities as required to support missile defense testing 
activities. Nearly all of the training and testing activities within 
the HRC take place within the smaller Hawaii OPAREA, which consists of 
235,000 nm\2\ of special use airspace, and sea and undersea space. The 
Hawaii OPAREA is the portion of the range complex immediately 
surrounding the island chain of Hawaii. Military activities and 
exercises were excluded from the list of prohibitions triggered when 
the Monument was established in 2006, so long as the activities are 
``carried out in a manner that avoids, to the extent practicable and 
consistent with operational requirements, adverse impacts on monument 
resources and qualities.'' More detailed information on the HRC, 
including maps, is provided in Chapter 2 of the Navy's LOA application 
(http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications).
    Southern California (SOCAL) Range Complex--The SOCAL Range Complex 
is situated between Dana Point and San Diego, and extends more than 600 
nm southwest into the Pacific Ocean. The two primary components of the 
SOCAL Range Complex are the ocean operating areas and the special use 
airspace. The SOCAL Range Complex includes San Diego Bay and a small 
portion of the Point Mugu Sea Range. The Silver Strand Training Complex 
is also included as part of the Southern California portion for this 
application. More detailed information on the SOCAL Range Complex, 
including maps, is provided in Chapter 2 of the Navy's LOA application 
(http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications).
    Transit Corridor--In addition to the three range complexes, a 
transit corridor outside the bounds of existing range

[[Page 6988]]

complexes is included in the Navy's request. This transit corridor is 
important to the Navy in that it provides adequate air, sea, and 
undersea space in which ships and aircraft can conduct training and 
some sonar maintenance and testing while en route between Southern 
California and Hawaii. The transit corridor is an area encompassing the 
shortest distance from San Diego to the center of the HRC. While in 
transit, ships and aircraft would, at times, conduct basic and routine 
unit level training as long as the training does not interfere with the 
primary objective of reaching their intended destination. Ships would 
also conduct sonar maintenance, which includes active sonar 
transmissions. The portion of the transit corridor to the east of 
140[deg] west longitude is included in the analysis of SOCAL activities 
and the area to the west of that meridian is included in the analysis 
of HRC activities since these portions of the corridor correspond with 
the marine mammal stocks in those range complexes.
    Pierside Locations--The Study Area also includes select pierside 
locations where Navy surface ship and submarine sonar maintenance 
testing occur. These pierside locations include channels and transit 
routes in ports, and facilities associated with ports and shipyards at 
Navy piers in San Diego, California, and Navy piers, shipyards, and the 
Intermediate Maintenance Facility in Pearl Harbor, Hawaii.

Description of Marine Mammals in the Area of the Specified Activities

    Thirty-nine marine mammal species are known to occur in the Study 
Area, including seven mysticetes (baleen whales), 25 odontocetes 
(dolphins and toothed whales), six pinnipeds (seals and sea lions), and 
the Southern sea otter. Among these species, there are 72 stocks 
managed by NMFS or the U.S. Fish and Wildlife Service (USFWS) in the 
U.S. Exclusive Economic Zone (EEZ). These species and their numbers are 
presented in Table 9 and relevant information on their status, 
distribution, and seasonal distribution (when applicable) is presented 
in Chapter 4 of the Navy's LOA application (http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications). Consistent with NMFS most 
recent Pacific Stock Assessment Report, a single species may include 
multiple stocks recognized for management purposes (e.g., spinner 
dolphin), while other species are grouped into a single stock due to 
limited species-specific information (e.g., beaked whales belonging to 
the genus Mesoplodon).
    Species that may have once inhabited and transited the Study Area, 
but have not been sighted in recent years, include the North Pacific 
right whale (Eubalaena japonica), harbor porpoise (Phocoena phocoena), 
and Steller sea lion (Eumetopias jubatus). These species are not 
expected to be exposed to or affected by any project activities and, 
therefore, are not discussed further.

                                 Table 9--Marine Mammals With Possible or Confirmed Presence Within the HSTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                        Stock          Study area       Occurrence in
          Common name            Scientific name    Study area         Stock         abundance CV   abundance  (CV)      study area     ESA/MMPA  Status
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Order Cetacea
                                                           Suborder Mysticeti (Baleen Whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Family Balaenopteridae (Rorquals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale................  Megaptera          SOCAL         California,        2,043          36                 Seasonal; More    Endangered/
                                 novaeangliae.                    Oregon, &         -0.1           -0.51               sightings         Depleted.
                                                                  Washington.                                          around the
                                                                                                                       northern
                                                                                                                       Channel Islands.
                                                   HRC           Central North      10,103         4,491              Seasonal;         Endangered/
                                                                  Pacific.          (N/A)          (N/A)               Throughout        Depleted.
                                                                                                                       known breeding
                                                                                                                       grounds during
                                                                                                                       winter and
                                                                                                                       spring (most
                                                                                                                       common November
                                                                                                                       through April).
Blue whale....................  Balaenoptera       SOCAL         Eastern North      2,497          842                Seasonal; arrive  Endangered/
                                 musculus.                        Pacific.          -0.24          -0.2                April-May; more   Depleted.
                                                                                                                       common late
                                                                                                                       summer to fall.
                                                   HRC           Central North      No data.       No data.           Seasonal;         Endangered/
                                                                  Pacific.                                             infrequent        Depleted.
                                                                                                                       winter migrant;
                                                                                                                       few sightings.
Fin whale.....................  Balaenoptera       SOCAL         California,        3,044          359                Year-round        Endangered/
                                 physalus.                        Oregon, &         -0.18          -0.4                presence.         Depleted.
                                                                  Washington.
                                                   HRC           Hawaiian.........  174            174                Seasonal; mainly  Endangered/
                                                                                    -0.72          -0.72               fall and winter   Depleted.
                                                                                                                       although
                                                                                                                       considered rare
                                                                                                                       in HRC.
Sei whale.....................  Balaenoptera       SOCAL         Eastern North      126            7                  Rare;             Endangered/
                                 borealis.                        Pacific.          -0.53          -1.07               infrequently      Depleted.
                                                                                                                       sighted in
                                                                                                                       California.
                                                                                                                       Only nine
                                                                                                                       confirmed
                                                                                                                       sightings on WA/
                                                                                                                       OR/CA surveys
                                                                                                                       from 1991-2008.

[[Page 6989]]

 
                                                   HRC           Hawaiian.........  77             77                 Rare; limited     Endangered/
                                                                                    -1.06          -1.06               sightings of      Depleted.
                                                                                                                       seasonal
                                                                                                                       migrants that
                                                                                                                       feed at higher
                                                                                                                       latitudes.
Bryde's whale.................  Balaenoptera       SOCAL         Eastern Tropical   13,000         7                  Limited summer    ................
                                 edeni.                           Pacific.          -0.2           -1.07               occurrence.
                                                   HRC           Hawaiian.........  469            469                Uncommon;         ................
                                                                                    -0.45          -0.45               distributed
                                                                                                                       throughout the
                                                                                                                       Hawaii
                                                                                                                       Exclusive
                                                                                                                       Economic Zone.
Minke whale...................  Balaenoptera       SOCAL         California,        478            226                Less common in    ................
                                 acutorostrata.                   Oregon, &         -1.36          -1.02               summer; small
                                                                  Washington.                                          numbers around
                                                                                                                       northern
                                                                                                                       Channel Islands.
                                                   HRC           Hawaiian.........  No data.       No data.           Regular but       ................
                                                                                                                       seasonal
                                                                                                                       occurrence
                                                                                                                       (November-March
                                                                                                                       ).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Family Eschrichtildae (Gray Whale)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gray whale....................  Eschrichtius       SOCAL         Eastern North      18,813         Population         Transient during  ................
                                 robustus.                        Pacific.          -0.07           migrates through   seasonal
                                                                                                    SOCAL              migrations.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          Suborder Odontoceti (Toothed Whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Family Physeteridae (Sperm Whale)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale...................  Physeter           SOCAL         California,        971            607                Common year       Endangered/
                                 macrocephalus.                   Oregon, &         -0.31          -0.57               round; more       Depleted.
                                                                  Washington.                                          likely in
                                                                                                                       waters > 1,000
                                                                                                                       m, most often >
                                                                                                                       2,000 m.
                                                   HRC           Hawaiian.........  6,919          6,919              Widely            Endangered/
                                                                                    -0.81          -0.81               distributed       Depleted.
                                                                                                                       year round;
                                                                                                                       more likely in
                                                                                                                       waters > 1,000
                                                                                                                       m, most often >
                                                                                                                       2,000 m.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Family Kogiidae (Pygmy and Dwarf Sperm Whale)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pygmy sperm whale.............  Kogia breviceps..  SOCAL         California,        579            .................  Seaward of 500-   ................
                                                                  Oregon, &         -1.02                              1000 m; limited
                                                                  Washington.                                          sightings over
                                                                                                                       entire Southern
                                                                                                                       Cal. Bight.
                                HRC                Hawaiian      7,138............  7,138          Stranding numbers
                                                                 -1.12............  -1.12           suggest this
                                                                                                    species is more
                                                                                                    common than
                                                                                                    infrequent
                                                                                                    sightings during
                                                                                                    survey (Barlow
                                                                                                    2006) indicated.
Dwarf sperm whale.............  Kogia sima.......  SOCAL         California,        Unknown        .................  Seaward of 500-   ................
                                                                  Oregon, &                                            1000 m; no
                                                                  Washington.                                          confirmed
                                                                                                                       sightings over
                                                                                                                       entire Southern
                                                                                                                       Cal. Bight (all
                                                                                                                       Kogia spp. or
                                                                                                                       Kogia
                                                                                                                       breviceps).

[[Page 6990]]

 
                                                   HRC           Hawaiian.........  17,519         17,519             Stranding         ................
                                                                                    -0.74          -0.74               numbers suggest
                                                                                                                       this species is
                                                                                                                       more common
                                                                                                                       than infrequent
                                                                                                                       sightings
                                                                                                                       during survey
                                                                                                                       (Barlow 2006)
                                                                                                                       indicated.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Family Delphinidae (Dolphins)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Killer whale..................  Orcinus orca.....  SOCAL         Eastern North      240            30                 Uncommon; occurs  ................
                                                                  Pacific Offshore. -0.49          -0.73               infrequently;
                                                                                                                       more likely in
                                                                                                                       winter.
                                                   SOCAL         Eastern North      451            .................  Uncommon; occurs  ................
                                                                  Pacific           -0.49                              infrequently;
                                                                  Transient.                                           more likely in
                                                                                                                       winter.
                                                   HRC           Hawaiian.........  349            349                Uncommon;         ................
                                                                                    -0.98          -0.98               infrequent
                                                                                                                       sightings.
False killer whale............  Pseudorca          SOCAL         Eastern Tropical   Unknown        .................  Uncommon; warm    ................
                                 crassidens.                      Pacific.                                             water species;
                                                                                                                       although
                                                                                                                       stranding
                                                                                                                       records from
                                                                                                                       the Channel
                                                                                                                       Islands.
                                                   HRC           Hawaii Insular     151            151                Regular.........  Endangered.
                                                                  [7],[8].          -0.2           -0.2
                                                   HRC           Hawaii Pelagic     1,503          1,503              Regular.........  ................
                                                                  \7\.              -0.66          -0.66
                                                   HRC           Northwest          522            522                Regular.........  ................
                                                                  Hawaiian Islands  -1.09          -1.09
                                                                  \7\.
Pygmy killer whale............  Feresa attenuata.  SOCAL         Tropical.........  Unknown        Extralimital.      Extralimital      ................
                                                                                                                       within the
                                                                                                                       south-west
                                                                                                                       boundary of the
                                                                                                                       SOCAL Range
                                                                                                                       Complex.
                                                   HRC           Hawaiian.........  956            956                Year-round        ................
                                                                                    -0.83          -0.83               resident;
                                                                                                                       abundance based
                                                                                                                       on 3 sightings
                                                                                                                       (Barlow 2006)..
Short-finned pilot whale......  Globicephala       SOCAL         California,        760            118                Uncommon; more    ................
                                 macrorhynchus.                   Oregon, &         -0.64          -1.04               common before
                                                                  Washington.                                          1982.
                                                   HRC           Hawaiian.........  8,870          8,870              Commonly          ................
                                                                                    -0.38          -0.38               observed around
                                                                                                                       main Hawaiian
                                                                                                                       Islands and
                                                                                                                       Northwestern
                                                                                                                       Hawaiian
                                                                                                                       Islands.
                                                                ----------------------------------------------------------------------------------------
Melon-headed whale............  Peponocephala      SOCAL                                           No known occurrence
                                 electra.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC           Hawaiian.........  2,950          2,950              Regular.........
                                                                                    -1.17          -1.17
Long-beaked common dolphin....  Delphinus          SOCAL         California.......  27,046         17,530             Common; more      ................
                                 capensis.                                          -0.59          -0.57               inshore
                                                                                                                       distribution
                                                                                                                       (within 50 nm
                                                                                                                       of coast).
                                                                ----------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
                                                                ----------------------------------------------------------------------------------------
Short-beaked common dolphin...  Delphinus delphis  SOCAL         California,        411,211        165,400            Common; one of    ................
                                                                  Oregon, &         -0.21          -0.19               the most
                                                                  Washington.                                          abundant SOCAL
                                                                                                                       dolphins;
                                                                                                                       higher summer
                                                                                                                       densities.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
                                                                ----------------------------------------------------------------------------------------

[[Page 6991]]

 
Bottlenose dolphin............  Tursiops           SOCAL         California         323            323                Limited, small    ................
                                 truncatus.                       Coastal.          -0.13          -0.13               population
                                                                                                                       within 1 km of
                                                                                                                       shore.
                                                   SOCAL         California,        1,006          1,831              Common..........  ................
                                                                  Oregon, &         -0.48          -0.47
                                                                  Washington
                                                                  Offshore.
                                                   HRC           Hawaii Pelagic...  3,178          3,178              Common in deep    ................
                                                                                    -0.59          -0.59               offshore waters.
                                                   HRC           Kauai and Niihau.  147            147                Common in         ................
                                                                                    -0.11          -0.11               shallow
                                                                                                                       nearshore
                                                                                                                       waters (1000 m
                                                                                                                       or less).
                                                   HRC           Oahu.............  594            594                Common in         ................
                                                                                    -0.54          -0.54               shallow
                                                                                                                       nearshore
                                                                                                                       waters (1000 m
                                                                                                                       or less).
                                                   HRC           4-Islands Region.  153            153                Common in         ................
                                                                                    -0.24          -0.24               shallow
                                                                                                                       nearshore
                                                                                                                       waters (1000 m
                                                                                                                       or less).
                                                   HRC           Hawaii Island....  102            102                Common in         ................
                                                                                    -0.13          -0.13               shallow
                                                                                                                       nearshore
                                                                                                                       waters (1000 m
                                                                                                                       or less).
Pantropical spotted dolphin...  Stenella           SOCAL         Eastern Tropical   Unknown.       .................  Rare; associated  ................
                                 attenuata.                       Pacific.                                             with warm
                                                                                                                       tropical
                                                                                                                       surface waters.
                                                   HRC           Hawaiian.........  8,978          8,978              Common; primary   ................
                                                                                    -0.48          -0.48               occurrence
                                                                                                                       between 100 and
                                                                                                                       4,000 meters
                                                                                                                       depth.
Striped dolphin...............  Stenella           SOCAL         California,        10,908         8,697              Occasional        ................
                                 coerulealba.                     Oregon, &         -0.34          -0.34               visitor; warm
                                                                  Washington.                                          water oceanic
                                                                                                                       species.
                                                   HRC           Hawaiian.........  13,143         13,143             Occurs regularly  ................
                                                                                    -0.46          -0.46               year round but
                                                                                                                       infrequent
                                                                                                                       sighting data.
                                                                ----------------------------------------------------------------------------------------
Spinner dolphin...............  Stenella           SOCAL                                           No known occurrence
                                 longirostris.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC           Hawaii Pelagic...  Unknown.       3,351              Common year       ................
                                                                                                   -0.74 for entire    round in
                                                                                                    Hawaiian Islands   offshore waters.
                                                                                                    Stock Complex
                                                   HRC           Hawaii Island....  Unknown.       3,351              Common year       ................
                                                                                                   -0.74 for entire    round; rest in
                                                                                                    Hawaiian Islands   nearshore
                                                                                                    Stock Complex      waters during
                                                                                                                       the day and
                                                                                                                       move offshore
                                                                                                                       to feed at
                                                                                                                       night.
                                                   HRC           Oahu/4-Islands...  Unknown.       3,351              Common year       ................
                                                                                                   -0.74 for entire    round; rest in
                                                                                                    Hawaiian Islands   nearshore
                                                                                                    Stock Complex      waters during
                                                                                                                       the day and
                                                                                                                       move offshore
                                                                                                                       to feed at
                                                                                                                       night.
                                                   HRC           Kauai/Niihau.....  Unknown.       3,351              Common year       ................
                                                                                                   -0.74 for entire    round; rest in
                                                                                                    Hawaiian Islands   nearshore
                                                                                                    Stock Complex      waters during
                                                                                                                       the day and
                                                                                                                       move offshore
                                                                                                                       to feed at
                                                                                                                       night.

[[Page 6992]]

 
                                                   HRC           Pearl and Hermes   Unknown.       3,351              Common year       ................
                                                                  Reef.                            -0.74 for entire    round; rest in
                                                                                                    Hawaiian Islands   nearshore
                                                                                                    Stock Complex      waters during
                                                                                                                       the day and
                                                                                                                       move offshore
                                                                                                                       to feed at
                                                                                                                       night.
                                                   HRC           Kure/Midway......  Unknown.       3,351              Common year       ................
                                                                                                   -0.74 for entire    round; rest in
                                                                                                    Hawaiian Islands   nearshore
                                                                                                    Stock Complex      waters during
                                                                                                                       the day and
                                                                                                                       move offshore
                                                                                                                       to feed at
                                                                                                                       night.
Rough-toothed dolphin.........  Steno bredanensis  SOCAL         Tropical and warm  Unknown.       .................  Rare; more        ................
                                                                  temperate.                                           tropical
                                                                                                                       offshore
                                                                                                                       species.
                                                   HRC           Hawaiian.........  8,709          8,709              Common            ................
                                                                                    -0.45          -0.45               throughout the
                                                                                                                       main Hawaiian
                                                                                                                       Islands and
                                                                                                                       Hawaii
                                                                                                                       Exclusive
                                                                                                                       Economic Zone.
Pacific white-sided dolphin...  Lagenorhynchus     SOCAL         California,        26,930         2,196              Common; year-     ................
                                 obliquidens.                     Oregon, &         -0.28          -0.71               round cool
                                                                  Washington.                                          water species;
                                                                                                                       more abundant
                                                                                                                       November-April.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
--------------------------------------------------------------------------------------------------------------------------------------------------------
Northern right whale dolphin..  Lissodelphis       SOCAL         California,        8,334          1,172              Common; cool      ................
                                 borealis.                        Oregon, &         -0.4           -0.52               water species;
                                                                  Washington.                                          more abundant
                                                                                                                       November-April.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
                                                                ----------------------------------------------------------------------------------------
Fraser's dolphin..............  Lagenodelphis      SOCAL                                           No known occurrence
                                 hosei.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC           Hawaiian.........  10,226         10,226             Tropical species  ................
                                                                                    -1.16          -1.16               only recently
                                                                                                                       documented
                                                                                                                       within Hawaii
                                                                                                                       Exclusive
                                                                                                                       Economic Zone
                                                                                                                       (2002 survey).
Risso's dolphins..............  Grampus griseus..  SOCAL         California,        6,272          3,418              Common; present   ................
                                                                  Oregon, &         -0.3           -0.31               in summer, but
                                                                  Washington.                                          higher
                                                                                                                       densities
                                                                                                                       November-April.
                                                   HRC           Hawaiian.........  2,372          2,372              Have been         ................
                                                                                    -0.97          -0.97               considered rare
                                                                                                                       but six
                                                                                                                       sightings in
                                                                                                                       Hawaii
                                                                                                                       Exclusive
                                                                                                                       Economic Zone
                                                                                                                       during 2002
                                                                                                                       survey.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Family Phocoenidae (Porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dall's porpoise...............  Phocoenoidea       SOCAL         California,        42,000         727                Common in cold    ................
                                 dalli.                           Oregon, &         -0.33          -0.99               water periods;
                                                                  Washington.                                          more abundant
                                                                                                                       November-April.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
                                                                ----------------------------------------------------------------------------------------

[[Page 6993]]

 
                                                            Family Ziphiidae (Beaked Whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Cuvier's beaked whale.........  Ziphius            SOCAL         California,        2,143          911                Possible year-    ................
                                 cavirostris.                     Oregon, &         -0.65          -0.68               round
                                                                  Washington.                                          occurrence but
                                                                                                                       difficult to
                                                                                                                       detect due to
                                                                                                                       diving behavior.
                                                   HRC           Hawaiian.........  15,242         15,242             Year-round        ................
                                                                                    -1.43          -1.43               occurrence but
                                                                                                                       difficult to
                                                                                                                       detect due to
                                                                                                                       diving behavior.
Baird's beaked whale..........  Berardius bairdii  SOCAL         California,        907            127                Primarily along   ................
                                                                  Oregon, &         -0.49          -1.14               continental
                                                                  Washington.                                          slope from late
                                                                                                                       spring to early
                                                                                                                       fall.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
                                                                ----------------------------------------------------------------------------------------
Longman's beaked whale........  Indopacetus        SOCAL                                           No known occurrence
                                 pacificus.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC           Hawaiian.........  1,007          1,007              One of the        ................
                                                                                    -1.26          -1.26               rarest and
                                                                                                                       least known
                                                                                                                       cetacean
                                                                                                                       species;
                                                                                                                       abundance based
                                                                                                                       on Barlow 2006
                                                                                                                       with 3
                                                                                                                       sightings,
                                                                                                                       however,
                                                                                                                       multiple
                                                                                                                       sightings
                                                                                                                       during 2010
                                                                                                                       HICEAS.
Blainville's beaked whale.....  Mesoplodon         SOCAL         California,        603            132                Distributed       ................
                                 densirostris.                    Oregon, &         -1.16          (0.96; for          throughout deep
                                                                  Washington.                       Mesoplodon         waters and
                                                                                                    spp.).             continental
                                                                                                                       slope regions;
                                                                                                                       difficult to
                                                                                                                       detect given
                                                                                                                       diving behavior.
                                                   HRC           Hawaiian.........  2,872          2,872              Year-round        ................
                                                                                    -1.25          -1.25               occurrence but
                                                                                                                       difficult to
                                                                                                                       detect due to
                                                                                                                       diving behavior.
Mesoplodont beaked whales       Mesoplodon spp...  SOCAL         California,        1,024          132                Distributed       ................
 (SOCAL estimates also include                                    Oregon, &         -0.77          -0.96               throughout deep
 Blainville's beaked whale                                        Washington.                                          waters and
 listed separately above).                                                                                             continental
                                                                                                                       slope regions;
                                                                                                                       difficult to
                                                                                                                       detect given
                                                                                                                       diving
                                                                                                                       behavior.
                                                                                                                       Limited
                                                                                                                       sightings;
                                                                                                                       generally
                                                                                                                       seaward of 500-
                                                                                                                       1000 m.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC               No known occurrence of five Mesoplodon species (M. carlhubbsi, M. ginkgodens, M.
                                                                                          perrini, M. peruvianus, M. stejnegeri)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Suborder Pinnipedia [9, 10]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Family Otariidae (Fur Seals and Sea Lions)
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion...........  Zalophus           SOCAL         U.S. Stock.......  238,000        .................  Most common       ................
                                 californianus.                                                                        pinniped,
                                                                                                                       Channel Islands
                                                                                                                       breeding sites
                                                                                                                       in summer.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
                                                                ----------------------------------------------------------------------------------------

[[Page 6994]]

 
Northern fur seal.............  Callorhinus        SOCAL         San Miguel Island  9,968          Stock is outside   Common; small     ................
                                 ursinus.                                                           of SOCAL.          population
                                                                                                                       breeds on San
                                                                                                                       Miguel Island.
                                                                                                                       May-October.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
                                                                ----------------------------------------------------------------------------------------
Guadalupe fur seal............  Arctocephalus      SOCAL         Mexico...........  7,408          .................  Rare; Occasional  Threatened/
                                 townsendi.                                                                            visitor to        Depleted.
                                                                                                                       northern
                                                                                                                       Channel
                                                                                                                       Islands; mainly
                                                                                                                       breeds on
                                                                                                                       Guadalupe
                                                                                                                       Island, Mexico,
                                                                                                                       May-July.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Family Phocidae (True Seals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Hawaiian monk seal............  Monachus           SOCAL                                           No known occurrence
                                 schauinslandi.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   HRC           Hawaiian.........  1,161          1,161              Predominantly     Endangered/
                                                                                                                       occur at          Depleted.
                                                                                                                       Northwestern
                                                                                                                       Hawaiian
                                                                                                                       Islands;
                                                                                                                       approximately
                                                                                                                       150 in Main
                                                                                                                       Hawaiian
                                                                                                                       Islands.
Northern elephant seal........  Mirounga           SOCAL         California         124,000        SNI 9,794 pups in  Common; Channel   ................
                                 angustirostris.                  Breeding.                         2000. SCI up to    Island haul-
                                                                                                    16 through 2000    outs of
                                                                                                                       different age
                                                                                                                       classes;
                                                                                                                       including SCI
                                                                                                                       December-March
                                                                                                                       and April-
                                                                                                                       August; spend 8-
                                                                                                                       10 months at
                                                                                                                       sea.
                                                   HRC                              .............  .................  Extralimital....
Harbor seal...................  Phoca vitulina...  SOCAL         California.......  34,233         5,271              Common; Channel   ................
                                                                                                   (All age classes    Islands haul-
                                                                                                    from aerial        outs including
                                                                                                    counts).           SCI and La
                                                                                                                       Jolla; bulk of
                                                                                                                       stock found
                                                                                                                       north of Pt.
                                                                                                                       Conception.
                                                                ----------------------------------------------------------------------------------------
                                                   HRC                                             No known occurrence
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Information on the status, distribution, abundance, and 
vocalizations of marine mammal species in the Study Area may be viewed 
in Chapter 4 of their LOA application (http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications). Further information on the 
general biology and ecology of marine mammals is included in the HSTT 
Draft EIS/OEIS. In addition, NMFS publishes annual stock assessment 
reports for marine mammals, including stocks that occur within the 
Study Area (http://www.nmfs.noaa.gov/pr/species/mammals).

Marine Mammal Hearing and Vocalizations

    Cetaceans have an auditory anatomy that follows the basic mammalian 
pattern, with some changes to adapt to the demands of hearing 
underwater. The typical mammalian ear is divided into an outer ear, 
middle ear, and inner ear. The outer ear is separated from the inner 
ear by a tympanic membrane, or eardrum. In terrestrial mammals, the 
outer ear, eardrum, and middle ear transmit airborne sound to the inner 
ear, where the sound waves are propagated through the cochlear fluid. 
Since the impedance of water is close to that of the tissues of a 
cetacean, the outer ear is not required to transduce sound energy as it 
does when sound waves travel from air to fluid (inner ear). Sound waves 
traveling through the inner ear cause the basilar membrane to vibrate. 
Specialized cells, called hair cells, respond to the vibration and 
produce nerve pulses that are transmitted to the central nervous 
system. Acoustic energy causes the basilar membrane in the cochlea to 
vibrate. Sensory cells at different positions along the basilar 
membrane are excited by different frequencies of sound (Pickles, 1998).
    Marine mammal vocalizations often extend both above and below the 
range of human hearing; vocalizations with frequencies lower than 20 Hz 
are labeled as infrasonic and those higher than 20 kHz as ultrasonic 
(National Research Council (NRC), 2003; Figure 4-1). Measured data on 
the hearing abilities of cetaceans are sparse, particularly for the 
larger cetaceans such as the baleen whales. The auditory thresholds of 
some of the smaller

[[Page 6995]]

odontocetes have been determined in captivity. It is generally believed 
that cetaceans should at least be sensitive to the frequencies of their 
own vocalizations. Comparisons of the anatomy of cetacean inner ears 
and models of the structural properties and the response to vibrations 
of the ear's components in different species provide an indication of 
likely sensitivity to various sound frequencies. The ears of small 
toothed whales are optimized for receiving high-frequency sound, while 
baleen whale inner ears are best in low to infrasonic frequencies 
(Ketten, 1992; 1997; 1998).
    Baleen whale vocalizations are composed primarily of frequencies 
below 1 kHz, and some contain fundamental frequencies as low as 16 Hz 
(Watkins et al., 1987; Richardson et al., 1995; Rivers, 1997; Moore et 
al., 1998; Stafford et al., 1999; Wartzok and Ketten, 1999) but can be 
as high as 24 kHz (humpback whale; Au et al., 2006). Clark and Ellison 
(2004) suggested that baleen whales use low-frequency sounds not only 
for long-range communication, but also as a simple form of echo 
ranging, using echoes to navigate and orient relative to physical 
features of the ocean. Information on auditory function in baleen 
whales is extremely lacking. Sensitivity to low-frequency sound by 
baleen whales has been inferred from observed vocalization frequencies, 
observed reactions to playback of sounds, and anatomical analyses of 
the auditory system. Although there is apparently much variation, the 
source levels of most baleen whale vocalizations lie in the range of 
150-190 dB re 1 [micro]Pa at 1 m. Low-frequency vocalizations made by 
baleen whales and their corresponding auditory anatomy suggest that 
they have good low-frequency hearing (Ketten, 2000), although specific 
data on sensitivity, frequency or intensity discrimination, or 
localization abilities are lacking. Marine mammals, like all mammals, 
have typical U-shaped audiograms that begin with relatively low 
sensitivity (high threshold) at some specified low frequency with 
increased sensitivity (low threshold) to a species specific optimum 
followed by a generally steep rise at higher frequencies (high 
threshold) (Fay, 1988).
    The toothed whales produce a wide variety of sounds, which include 
species-specific broadband ``clicks'' with peak energy between 10 and 
200 kHz, individually variable ``burst pulse'' click trains, and 
constant frequency or frequency-modulated (FM) whistles ranging from 4 
to 16 kHz (Wartzok and Ketten, 1999). The general consensus is that the 
tonal vocalizations (whistles) produced by toothed whales play an 
important role in maintaining contact between dispersed individuals, 
while broadband clicks are used during echolocation (Wartzok and 
Ketten, 1999). Burst pulses have also been strongly implicated in 
communication, with some scientists suggesting that they play an 
important role in agonistic encounters (McCowan and Reiss, 1995), while 
others have proposed that they represent ``emotive'' signals in a 
broader sense, possibly representing graded communication signals 
(Herzing, 1996). Sperm whales, however, are known to produce only 
clicks, which are used for both communication and echolocation 
(Whitehead, 2003). Most of the energy of toothed whale social 
vocalizations is concentrated near 10 kHz, with source levels for 
whistles as high as 100 to 180 dB re 1 [micro]Pa at 1 m (Richardson et 
al., 1995). No odontocete has been shown audiometrically to have acute 
hearing (<80 dB re 1 [micro]Pa) below 500 Hz (DoN, 2001). Sperm whales 
produce clicks, which may be used to echolocate (Mullins et al., 1988), 
with a frequency range from less than 100 Hz to 30 kHz and source 
levels up to 230 dB re 1 [micro]Pa 1 m or greater (Mohl et al., 2000).

Marine Mammal Density Estimates

    A quantitative analysis of impacts on a species requires data on 
the abundance and distribution of the species population in the 
potentially impacted area. One metric for performing this type of 
analysis is density, which is the number of animals present per unit 
area. The Navy compiled existing, publically available density data for 
use in the quantitative acoustic impact analysis. There is no single 
source of density data for every area of the world, species, and season 
because of the costs, resources, and effort required to provide 
adequate survey coverage to sufficiently estimate density. Therefore, 
to estimate marine mammal densities for large areas like the HSTT Study 
Area, the Navy compiled data from several sources. The Navy developed a 
hierarchy of density data sources to select the best available data 
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 (Navy, 2012).
    The Navy Marine Species Density Database includes a compilation of 
the best available density data from several primary sources and 
published works including survey data from NMFS within the U.S. 
Exclusive Economic Zone. The Navy ranked their modeling methods as 
follows:
    1. Density spatial model based estimates will be used when 
available (e.g., NMFS' Southwest Fisheries Science Center models for 
the California Current Ecosystem and the Central Pacific).
    2. If no density spatial model based estimates are available, the 
following can be used in order of preference:
    a. Density estimates using designed-based methods incorporating 
line-transect survey data and involving spatial stratification (i.e., 
estimates split by depth strata or arbitrary survey sub-regions).
    b. Density estimates using designed-based methods incorporating 
only line-transect survey data (i.e., regional density estimate, stock 
assessment report).
    c. Density estimates derived using a Relative Environmental 
Suitability (RES) model in conjunction with survey data from Sea Mammal 
Research Unit (SMRU) Ltd or in conjunction with a global population 
estimate from Kaschner et al.'s (2006) density data.
    In some cases, extrapolation from neighboring regional density 
estimates or population/stock assessments is appropriate based on 
expert opinion. This is often preferred over using RES models because 
of discrepancies identified by local expert knowledge. This includes an 
extrapolation of no occurrence based on other sources of data such as 
the NMFS stock assessment reports or expert judgment. Additional 
information on the density data sources and how the database was 
applied to the HSTT Study Area is detailed in the Navy Marine Species 
Density Database Technical Report (http://hstteis.com/DocumentsandReferences/HSTTDocuments/SupportingTechnicalDocuments.aspx">hstteis.com/DocumentsandReferences/HSTTDocuments/SupportingTechnicalDocuments.aspx).

Brief Background on Sound

    An understanding of the basic properties of underwater sound is 
necessary to comprehend many of the concepts and analyses presented in 
this document. A summary is included below.
    Sound is a wave of pressure variations propagating through a medium 
(e.g., water). Pressure variations are created by compressing and 
relaxing the medium. Sound measurements can be expressed in two forms: 
Intensity and pressure. Acoustic intensity is the average rate of 
energy transmitted through a unit area in a specified direction and is 
expressed in watts per square meter (W/m\2\). Acoustic intensity is 
rarely measured directly, but rather

[[Page 6996]]

from ratios of pressures; the standard reference pressure for 
underwater sound is 1 microPascal ([micro]Pa); for airborne sound, the 
standard reference pressure is 20 [micro]Pa (Richardson et al., 1995).
    Acousticians have adopted a logarithmic scale for sound 
intensities, which is denoted in decibels (dB). Decibel measurements 
represent the ratio between a measured pressure value and a reference 
pressure value (in this case 1 [micro]Pa or, for airborne sound, 20 
[micro]Pa). The logarithmic nature of the scale means that each 10-dB 
increase is a ten-fold increase in acoustic power (and a 20-dB increase 
is then a 100-fold increase in power; and a 30-dB increase is a 1,000-
fold increase in power). A ten-fold increase in acoustic power does not 
mean that the sound is perceived as being ten times louder, however. 
Humans perceive a 10-dB increase in sound level as a doubling of 
loudness, and a 10-dB decrease in sound level as a halving of loudness. 
The term ``sound pressure level'' implies a decibel measure and a 
reference pressure that is used as the denominator of the ratio. 
Throughout this document, NMFS uses 1 microPascal (denoted re: 
1[micro]Pa) as a standard reference pressure unless noted otherwise.
    It is important to note that decibel values underwater and decibel 
values in air are not the same (different reference pressures and 
densities/sound speeds between media) and should not be directly 
compared. Because of the different densities of air and water and the 
different decibel standards (i.e., reference pressures) in air and 
water, a sound with the same level in air and in water would be 
approximately 62 dB lower in air. Thus, a sound that measures 160 dB 
(re 1 [micro]Pa) underwater would have the same approximate effective 
level as a sound that is 98 dB (re 20 [micro]Pa) in air.
    Sound frequency is measured in cycles per second, or Hertz 
(abbreviated Hz), and is analogous to musical pitch; high-pitched 
sounds contain high frequencies and low-pitched sounds contain low 
frequencies. Natural sounds in the ocean span a huge range of 
frequencies: From earthquake noise at 5 Hz to harbor porpoise clicks at 
150,000 Hz (150 kHz). These sounds are so low or so high in pitch that 
humans cannot even hear them; acousticians call these infrasonic 
(typically below 20 Hz) and ultrasonic (typically above 20,000 Hz) 
sounds, respectively. A single sound may be made up of many different 
frequencies together. Sounds made up of only a small range of 
frequencies are called ``narrowband'', and sounds with a broad range of 
frequencies are called ``broadband''; explosives are an example of a 
broadband sound source and active tactical sonars are an example of a 
narrowband sound source.
    When considering the influence of various kinds of sound on the 
marine environment, it is necessary to understand that different kinds 
of marine life are sensitive to different frequencies of sound. Based 
on available behavioral data, audiograms derived using behavioral 
protocols or auditory evoked potential (AEP) techniques, anatomical 
modeling, and other data, Southall et al. (2007) designate ``functional 
hearing groups'' for marine mammals and estimate the lower and upper 
frequencies of functional hearing of the groups. Further, the frequency 
range in which each group's hearing is estimated as being most 
sensitive is represented in the flat part of the M-weighting functions 
(which are derived from the audiograms described above; see Figure 1 in 
Southall et al., 2007) developed for each broad group. The functional 
groups and the associated frequencies are indicated below (though, 
again, animals are less sensitive to sounds at the outer edge of their 
functional range and most sensitive to sounds of frequencies within a 
smaller range somewhere in the middle of their functional hearing 
range):
     Low-frequency cetaceans--functional hearing is estimated 
to occur between approximately 7 Hz and 30 kHz;
     Mid-frequency cetaceans--functional hearing is estimated 
to occur between approximately 150 Hz and 160 kHz;
     High-frequency cetaceans--functional hearing is estimated 
to occur between approximately 200 Hz and 180 kHz;
     Pinnipeds in water--functional hearing is estimated to 
occur between approximately 75 Hz and 75 kHz.
    The estimated hearing range for low-frequency cetaceans has been 
extended slightly from previous analyses (from 22 to 30 kHz). This 
decision is based on data from Watkins et al. (1986) for numerous 
mysticete species, Au et al. (2006) for humpback whales, an abstract 
from Frankel (2005) and paper from Lucifredi and Stein (2007) on gray 
whales, and an unpublished report (Ketten and Mountain, 2009) and 
abstract (Tubelli et al., 2012) for minke whales. As more data from 
more species and/or individuals become available, these estimated 
hearing ranges may require modification.
    When sound travels (propagates) from its source, its loudness 
decreases as the distance traveled by the sound increases. Thus, the 
loudness of a sound at its source is higher than the loudness of that 
same sound a kilometer away. Acousticians often refer to the loudness 
of a sound at its source (typically referenced to one meter from the 
source) as the source level and the loudness of sound elsewhere as the 
received level (i.e., typically the receiver). For example, a humpback 
whale 3 km from a device that has a source level of 230 dB may only be 
exposed to sound that is 160 dB loud, depending on how the sound 
travels through water (e.g., spherical spreading [3 dB reduction with 
doubling of distance] was used in this example). As a result, it is 
important to understand the difference between source levels and 
received levels when discussing the loudness of sound in the ocean or 
its impacts on the marine environment.
    As sound travels from a source, its propagation in water is 
influenced by various physical characteristics, including water 
temperature, depth, salinity, and surface and bottom properties that 
cause refraction, reflection, absorption, and scattering of sound 
waves. Oceans are not homogeneous and the contribution of each of these 
individual factors is extremely complex and interrelated. The physical 
characteristics that determine the sound's speed through the water will 
change with depth, season, geographic location, and with time of day 
(as a result, in actual active sonar operations, crews will measure 
oceanic conditions, such as sea water temperature and depth, to 
calibrate models that determine the path the sonar signal will take as 
it travels through the ocean and how strong the sound signal will be at 
a given range along a particular transmission path). As sound travels 
through the ocean, the intensity associated with the wavefront 
diminishes, or attenuates. This decrease in intensity is referred to as 
propagation loss, also commonly called transmission loss.

Metrics Used in This Document

    This section includes a brief explanation of the two sound 
measurements (sound pressure level (SPL) and sound exposure level 
(SEL)) frequently used to describe sound levels in the discussions of 
acoustic effects in this document.
    Sound pressure level (SPL)--Sound pressure is the sound force per 
unit area, and is usually measured in micropascals ([micro]Pa), where 1 
Pa is the pressure resulting from a force of one newton exerted over an 
area of one square meter. SPL is expressed as the ratio of a measured 
sound pressure and a reference level.


[[Page 6997]]


SPL (in dB) = 20 log (pressure/reference pressure)

    The commonly used reference pressure level in underwater acoustics 
is 1 [micro]Pa, and the units for SPLs are dB re: 1 [micro]Pa. SPL is 
an instantaneous pressure measurement and can be expressed as the peak, 
the peak-peak, or the root mean square (rms). Root mean square 
pressure, which is the square root of the arithmetic average of the 
squared instantaneous pressure values, is typically used in discussions 
of the effects of sounds on vertebrates and all references to SPL in 
this document refer to the root mean square. SPL does not take the 
duration of exposure into account. SPL is the applicable metric used in 
the risk continuum, which is used to estimate behavioral harassment 
takes (see Level B Harassment Risk Function (Behavioral Harassment) 
Section).
    Sound exposure level (SEL)--SEL is an energy metric that integrates 
the squared instantaneous sound pressure over a stated time interval. 
The units for SEL are dB re: 1 [micro]Pa\2\-s. Below is a simplified 
formula for SEL.

SEL = SPL + 10log(duration in seconds)

    As applied to active sonar, the SEL includes both the SPL of a 
sonar ping and the total duration. Longer duration pings and/or pings 
with higher SPLs will have a higher SEL. If an animal is exposed to 
multiple pings, the SEL in each individual ping is summed to calculate 
the cumulative SEL. The cumulative SEL depends on the SPL, duration, 
and number of pings received. The thresholds that NMFS uses to indicate 
at what received level the onset of temporary threshold shift (TTS) and 
permanent threshold shift (PTS) in hearing are likely to occur are 
expressed as cumulative SEL.

Potential Effects of Specified Activities on Marine Mammals

    The Navy has requested authorization for the take of marine mammals 
that may occur incidental to training and testing activities in the 
Study Area. The Navy has analyzed potential impacts to marine mammals 
from impulsive and non-impulsive sound sources and vessel strike.
    Other potential impacts to marine mammals from training activities 
in the Study Area were analyzed in the Navy's HSTT DEIS/OEIS, in 
consultation with NMFS as a cooperating agency, and determined to be 
unlikely to result in marine mammal harassment. Therefore, the Navy has 
not requested authorization for take of marine mammals that might occur 
incidental to other components of their proposed activities. In this 
document, NMFS analyzes the potential effects on marine mammals from 
exposure to non-impulsive sound sources (sonar and other active 
acoustic sources), impulsive sound sources (underwater detonations and 
pile driving), and vessel strikes.
    For the purpose of MMPA authorizations, NMFS' effects assessments 
serve four primary purposes: (1) To prescribe the permissible methods 
of taking (i.e., Level B harassment (behavioral harassment), Level A 
harassment (injury), or mortality, including an identification of the 
number and types of take that could occur by harassment or mortality) 
and to prescribe other means of effecting the least practicable adverse 
impact on such species or stock and its habitat (i.e., mitigation); (2) 
to determine whether the specified activity would have a negligible 
impact on the affected species or stocks of marine mammals (based on 
the likelihood that the activity would adversely affect the species or 
stock through effects on annual rates of recruitment or survival); (3) 
to determine whether the specified activity would have an unmitigable 
adverse impact on the availability of the species or stock(s) for 
subsistence uses; and (4) to prescribe requirements pertaining to 
monitoring and reporting.
    More specifically, for activities involving non-impulsive or 
impulsive sources, NMFS' analysis will identify the probability of 
lethal responses, physical trauma, sensory impairment (permanent and 
temporary threshold shifts and acoustic masking), physiological 
responses (particular stress responses), behavioral disturbance (that 
rises to the level of harassment), and social responses (effects to 
social relationships) that would be classified as a take and whether 
such take would have a negligible impact on such species or stocks. 
Vessel strikes, which have the potential to result in incidental take 
from direct injury and/or mortality, will be discussed in more detail 
in the Estimated Take of Marine Mammals section. In this section, we 
will focus qualitatively on the different ways that non-impulsive and 
impulsive sources may affect marine mammals (some of which NMFS would 
not classify as harassment). Then, in the Estimated Take of Marine 
Mammals section, we will relate the potential effects to marine mammals 
from non-impulsive and impulsive sources to the MMPA definitions of 
Level A and Level B Harassment, along with the potential effects from 
vessel strikes, and attempt to quantify those effects.

Non-Impulsive Sources

Direct Physiological Effects

    Based on the literature, there are two basic ways that non-
impulsive sources might directly result in physical trauma or damage: 
Noise-induced loss of hearing sensitivity (more commonly-called 
``threshold shift'') and acoustically mediated bubble growth. 
Separately, an animal's behavioral reaction to an acoustic exposure 
might lead to physiological effects that might ultimately lead to 
injury or death, which is discussed later in the Stranding section.
    Threshold Shift (noise-induced loss of hearing)--When animals 
exhibit reduced hearing sensitivity (i.e., sounds must be louder for an 
animal to detect them) following exposure to an intense sound or sound 
for long duration, it is referred to as a noise-induced threshold shift 
(TS). An animal can experience temporary threshold shift (TTS) or 
permanent threshold shift (PTS). TTS can last from minutes or hours to 
days (i.e., there is complete recovery), can occur in specific 
frequency ranges (i.e., an animal might only have a temporary loss of 
hearing sensitivity between the frequencies of 1 and 10 kHz), and can 
be of varying amounts (for example, an animal's hearing sensitivity 
might be reduced initially by only 6 dB or reduced by 30 dB). PTS is 
permanent, but some recovery is possible. PTS can also occur in a 
specific frequency range and amount as mentioned above for TTS.
    The following physiological mechanisms are thought to play a role 
in inducing auditory TS: Effects to sensory hair cells in the inner ear 
that reduce their sensitivity, modification of the chemical environment 
within the sensory cells, residual muscular activity in the middle ear, 
displacement of certain inner ear membranes, increased blood flow, and 
post-stimulatory reduction in both efferent and sensory neural output 
(Southall et al., 2007). The amplitude, duration, frequency, temporal 
pattern, and energy distribution of sound exposure all can affect the 
amount of associated TS and the frequency range in which it occurs. As 
amplitude and duration of sound exposure increase, so, generally, does 
the amount of TS, along with the recovery time. For intermittent 
sounds, less TS could occur than compared to a continuous exposure with 
the same energy (some recovery could occur between intermittent 
exposures depending on the duty cycle between sounds) (Kryter et al., 
1966; Ward, 1997). For example, one short but loud (higher SPL) sound 
exposure may

[[Page 6998]]

induce the same impairment as one longer but softer sound, which in 
turn may cause more impairment than a series of several intermittent 
softer sounds with the same total energy (Ward, 1997). Additionally, 
though TTS is temporary, prolonged exposure to sounds strong enough to 
elicit TTS, or shorter-term exposure to sound levels well above the TTS 
threshold, can cause PTS, at least in terrestrial mammals (Kryter, 
1985). Although in the case of mid- and high-frequency active sonar 
(MFAS/HFAS), animals are not expected to be exposed to levels high 
enough or durations long enough to result in PTS.
    PTS is considered auditory injury (Southall et al., 2007). 
Irreparable damage to the inner or outer cochlear hair cells may cause 
PTS; however, other mechanisms are also involved, such as exceeding the 
elastic limits of certain tissues and membranes in the middle and inner 
ears and resultant changes in the chemical composition of the inner ear 
fluids (Southall et al., 2007).
    Although the published body of scientific literature contains 
numerous theoretical studies and discussion papers on hearing 
impairments that can occur with exposure to a loud sound, only a few 
studies provide empirical information on the levels at which noise-
induced loss in hearing sensitivity occurs in nonhuman animals. For 
marine mammals, published data are limited to the captive bottlenose 
dolphin, beluga, harbor porpoise, and Yangtze finless porpoise 
(Finneran et al., 2000, 2002b, 2003, 2005a, 2007, 2010a, 2010b; 
Finneran and Schlundt, 2010; Lucke et al., 2009; Mooney et al., 2009a, 
2009b; Popov et al., 2011a, 2011b; Kastelein et al., 2012a; Schlundt et 
al., 2000; Nachtigall et al., 2003, 2004). For pinnipeds in water, data 
are limited to measurements of TTS in harbor seals, an elephant seal, 
and California sea lions (Kastak et al., 1999, 2005; Kastelein et al., 
2012b).
    Marine mammal hearing plays a critical role in communication with 
conspecifics, and interpretation of environmental cues for purposes 
such as predator avoidance and prey capture. Depending on the degree 
(elevation of threshold in dB), duration (i.e., recovery time), and 
frequency range of TTS, and the context in which it is experienced, TTS 
can have effects on marine mammals ranging from discountable to serious 
(similar to those discussed in auditory masking, below). For example, a 
marine mammal may be able to readily compensate for a brief, relatively 
small amount of TTS in a non-critical frequency range that occurs 
during a time where ambient noise is lower and there are not as many 
competing sounds present. Alternatively, a larger amount and longer 
duration of TTS sustained during time when communication is critical 
for successful mother/calf interactions could have more serious 
impacts. Also, depending on the degree and frequency range, the effects 
of PTS on an animal could range in severity, although it is considered 
generally more serious because it is a permanent condition. Of note, 
reduced hearing sensitivity as a simple function of aging has been 
observed in marine mammals, as well as humans and other taxa (Southall 
et al., 2007), so we can infer that strategies exist for coping with 
this condition to some degree, though likely not without cost.
    Acoustically Mediated Bubble Growth--One theoretical cause of 
injury to marine mammals is rectified diffusion (Crum and Mao, 1996), 
the process of increasing the size of a bubble by exposing it to a 
sound field. This process could be facilitated if the environment in 
which the ensonified bubbles exist is supersaturated with gas. 
Repetitive diving by marine mammals can cause the blood and some 
tissues to accumulate gas to a greater degree than is supported by the 
surrounding environmental pressure (Ridgway and Howard, 1979). The 
deeper and longer dives of some marine mammals (for example, beaked 
whales) are theoretically predicted to induce greater supersaturation 
(Houser et al., 2001b). If rectified diffusion were possible in marine 
mammals exposed to high-level sound, conditions of tissue 
supersaturation could theoretically speed the rate and increase the 
size of bubble growth. Subsequent effects due to tissue trauma and 
emboli would presumably mirror those observed in humans suffering from 
decompression sickness.
    It is unlikely that the short duration of sonar pings or explosion 
sounds would be long enough to drive bubble growth to any substantial 
size, if such a phenomenon occurs. However, an alternative but related 
hypothesis has also been suggested: Stable bubbles could be 
destabilized by high-level sound exposures such that bubble growth then 
occurs through static diffusion of gas out of the tissues. In such a 
scenario the marine mammal would need to be in a gas-supersaturated 
state for a long enough period of time for bubbles to become of a 
problematic size.
    Yet another hypothesis (decompression sickness) has speculated that 
rapid ascent to the surface following exposure to a startling sound 
might produce tissue gas saturation sufficient for the evolution of 
nitrogen bubbles (Jepson et al., 2003; Fernandez et al., 2005). In this 
scenario, the rate of ascent would need to be sufficiently rapid to 
compromise behavioral or physiological protections against nitrogen 
bubble formation. Alternatively, Tyack et al. (2006) studied the deep 
diving behavior of beaked whales and concluded that: ``Using current 
models of breath-hold diving, we infer that their natural diving 
behavior is inconsistent with known problems of acute nitrogen 
supersaturation and embolism.'' Collectively, these hypotheses can be 
referred to as ``hypotheses of acoustically mediated bubble growth.''
    Although theoretical predictions suggest the possibility for 
acoustically mediated bubble growth, there is considerable disagreement 
among scientists as to its likelihood (Piantadosi and Thalmann, 2004; 
Evans and Miller, 2003). Crum and Mao (1996) hypothesized that received 
levels would have to exceed 190 dB in order for there to be the 
possibility of significant bubble growth due to supersaturation of 
gases in the blood (i.e., rectified diffusion). More recent work 
conducted by Crum et al. (2005) demonstrated the possibility of 
rectified diffusion for short duration signals, but at SELs and tissue 
saturation levels that are highly improbable to occur in diving marine 
mammals. To date, energy levels (ELs) predicted to cause in vivo bubble 
formation within diving cetaceans have not been evaluated (NOAA, 
2002b). Although it has been argued that traumas from some recent 
beaked whale strandings are consistent with gas emboli and bubble-
induced tissue separations (Jepson et al., 2003), there is no 
conclusive evidence of this. However, Jepson et al. (2003, 2005) and 
Fernandez et al. (2004, 2005) concluded that in vivo bubble formation, 
which may be exacerbated by deep, long-duration, repetitive dives may 
explain why beaked whales appear to be particularly vulnerable to sonar 
exposures. Further investigation is needed to further assess the 
potential validity of these hypotheses. More information regarding 
hypotheses that attempt to explain how behavioral responses to non-
impulsive sources can lead to strandings is included in the Stranding 
and Mortality section.

Acoustic Masking

    Marine mammals use acoustic signals for a variety of purposes, 
which differ among species, but include communication between 
individuals, navigation, foraging, reproduction, and

[[Page 6999]]

learning about their environment (Erbe and Farmer 2000, Tyack 2000). 
Masking, or auditory interference, generally occurs when sounds in the 
environment are louder than and of a similar frequency to, auditory 
signals an animal is trying to receive. Masking is a phenomenon that 
affects animals that are trying to receive acoustic information about 
their environment, including sounds from other members of their 
species, predators, prey, and sounds that allow them to orient in their 
environment. Masking these acoustic signals can disturb the behavior of 
individual animals, groups of animals, or entire populations.
    The extent of the masking interference depends on the spectral, 
temporal, and spatial relationships between the signals an animal is 
trying to receive and the masking noise, in addition to other factors. 
In humans, significant masking of tonal signals occurs as a result of 
exposure to noise in a narrow band of similar frequencies. As the sound 
level increases, though, the detection of frequencies above those of 
the masking stimulus decreases also. This principle is expected to 
apply to marine mammals as well because of common biomechanical 
cochlear properties across taxa.
    Richardson et al. (1995b) argued that the maximum radius of 
influence of an industrial noise (including broadband low frequency 
sound transmission) on a marine mammal is the distance from the source 
to the point at which the noise can barely be heard. This range is 
determined by either the hearing sensitivity of the animal or the 
background noise level present. Industrial masking is most likely to 
affect some species' ability to detect communication calls and natural 
sounds (i.e., surf noise, prey noise, etc.; Richardson et al., 1995).
    The echolocation calls of toothed whales are subject to masking by 
high frequency sound. Human data indicate low-frequency sound can mask 
high-frequency sounds (i.e., upward masking). Studies on captive 
odontocetes by Au et al. (1974, 1985, 1993) indicate that some species 
may use various processes to reduce masking effects (e.g., adjustments 
in echolocation call intensity or frequency as a function of background 
noise conditions). There is also evidence that the directional hearing 
abilities of odontocetes are useful in reducing masking at the high-
frequencies these cetaceans use to echolocate, but not at the low-to-
moderate frequencies they use to communicate (Zaitseva et al.,1980). A 
recent study by Nachtigall and Supin (2008) showed that false killer 
whales adjust their hearing to compensate for ambient sounds and the 
intensity of returning echolocation signals.
    As mentioned previously, the functional hearing ranges of 
mysticetes, odontocetes, and pinnipeds underwater all encompass the 
frequencies of the sonar sources used in the Navy's MFAS/HFAS training 
exercises. Additionally, almost all species' vocal repertoires span 
across the frequencies of these sonar sources used by the Navy. The 
closer the characteristics of the masking signal to the signal of 
interest, the more likely masking is to occur. For hull-mounted sonar, 
which accounts for the largest takes of marine mammals (because of the 
source strength and number of hours it's conducted), the pulse length 
and low duty cycle of the MFAS/HFAS signal makes it less likely that 
masking would occur as a result.

Impaired Communication

    In addition to making it more difficult for animals to perceive 
acoustic cues in their environment, anthropogenic sound presents 
separate challenges for animals that are vocalizing. When they 
vocalize, animals are aware of environmental conditions that affect the 
``active space'' of their vocalizations, which is the maximum area 
within which their vocalizations can be detected before it drops to the 
level of ambient noise (Brenowitz, 2004; Brumm et al., 2004; Lohr et 
al., 2003). Animals are also aware of environmental conditions that 
affect whether listeners can discriminate and recognize their 
vocalizations from other sounds, which is more important than simply 
detecting that a vocalization is occurring (Brenowitz, 1982; Brumm et 
al., 2004; Dooling, 2004, Marten and Marler, 1977; Patricelli et al., 
2006). Most animals that vocalize have evolved with an ability to make 
adjustments to their vocalizations to increase the signal-to-noise 
ratio, active space, and recognizability/distinguishability of their 
vocalizations in the face of temporary changes in background noise 
(Brumm et al., 2004; Patricelli et al., 2006). Vocalizing animals can 
make adjustments to vocalization characteristics such as the frequency 
structure, amplitude, temporal structure, and temporal delivery.
    Many animals will combine several of these strategies to compensate 
for high levels of background noise. Anthropogenic sounds that reduce 
the signal-to-noise ratio of animal vocalizations, increase the masked 
auditory thresholds of animals listening for such vocalizations, or 
reduce the active space of an animal's vocalizations impair 
communication between animals. Most animals that vocalize have evolved 
strategies to compensate for the effects of short-term or temporary 
increases in background or ambient noise on their songs or calls. 
Although the fitness consequences of these vocal adjustments remain 
unknown, like most other trade-offs animals must make, some of these 
strategies probably come at a cost (Patricelli et al., 2006). For 
example, vocalizing more loudly in noisy environments may have 
energetic costs that decrease the net benefits of vocal adjustment and 
alter a bird's energy budget (Brumm, 2004; Wood and Yezerinac, 2006). 
Shifting songs and calls to higher frequencies may also impose 
energetic costs (Lambrechts, 1996).

Stress Responses

    Classic stress responses begin when an animal's central nervous 
system perceives a potential threat to its homeostasis. That perception 
triggers stress responses regardless of whether a stimulus actually 
threatens the animal; the mere perception of a threat is sufficient to 
trigger a stress response (Moberg, 2000; Sapolsky et al., 2005; Seyle, 
1950). Once an animal's central nervous system perceives a threat, it 
mounts a biological response or defense that consists of a combination 
of the four general biological defense responses: Behavioral responses, 
autonomic nervous system responses, neuroendocrine responses, or immune 
responses.
    In the case of many stressors, an animal's first and sometimes most 
economical (in terms of biotic costs) response is behavioral avoidance 
of the potential stressor or avoidance of continued exposure to a 
stressor. An animal's second line of defense to stressors involves the 
sympathetic part of the autonomic nervous system and the classical 
``fight or flight'' response which includes the cardiovascular system, 
the gastrointestinal system, the exocrine glands, and the adrenal 
medulla to produce changes in heart rate, blood pressure, and 
gastrointestinal activity that humans commonly associate with 
``stress.'' These responses have a relatively short duration and may or 
may not have significant long-term effect on an animal's welfare.
    An animal's third line of defense to stressors involves its 
neuroendocrine systems; the system that has received the most study has 
been the hypothalmus-pituitary-adrenal system (also known as the HPA 
axis in mammals or the hypothalamus-pituitary-interrenal axis in fish 
and some reptiles). Unlike stress responses associated with the 
autonomic nervous

[[Page 7000]]

system, virtually all neuro-endocrine functions that are affected by 
stress--including immune competence, reproduction, metabolism, and 
behavior--are regulated by pituitary hormones. Stress-induced changes 
in the secretion of pituitary hormones have been implicated in failed 
reproduction (Moberg, 1987; Rivier, 1995), altered metabolism (Elasser 
et al., 2000), reduced immune competence (Blecha, 2000), and behavioral 
disturbance. Increases in the circulation of glucocorticosteroids 
(cortisol, corticosterone, and aldosterone in marine mammals; see 
Romano et al., 2004) have been equated with stress for many years.
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and distress is the biotic cost 
of the response. During a stress response, an animal uses glycogen 
stores that can be quickly replenished once the stress is alleviated. 
In such circumstances, the cost of the stress response would not pose a 
risk to the animal's welfare. However, when an animal does not have 
sufficient energy reserves to satisfy the energetic costs of a stress 
response, energy resources must be diverted from other biotic function, 
which impairs those functions that experience the diversion. For 
example, when mounting a stress response diverts energy away from 
growth in young animals, those animals may experience stunted growth. 
When mounting a stress response diverts energy from a fetus, an 
animal's reproductive success and its fitness will suffer. In these 
cases, the animals will have entered a pre-pathological or pathological 
state which is called ``distress'' (sensu Seyle 1950) or ``allostatic 
loading'' (sensu McEwen and Wingfield, 2003). This pathological state 
will last until the animal replenishes its biotic reserves sufficient 
to restore normal function. Note that these examples involved a long-
term (days or weeks) stress response exposure to stimuli.
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses have also been documented 
fairly well through controlled experiments; because this physiology 
exists in every vertebrate that has been studied, it is not surprising 
that stress responses and their costs have been documented in both 
laboratory and free-living animals (for examples see, Holberton et al., 
1996; Hood et al., 1998; Jessop et al., 2003; Krausman et al., 2004; 
Lankford et al., 2005; Reneerkens et al., 2002; Thompson and Hamer, 
2000). Information has also been collected on the physiological 
responses of marine mammals to exposure to anthropogenic sounds (Fair 
and Becker, 2000; Romano et al., 2002; Wright et al., 2008). For 
example, Rolland et al. (2012) found that noise reduction from reduced 
ship traffic in the Bay of Fundy was associated with decreased stress 
in North Atlantic right whales. In a conceptual model developed by the 
Population Consequences of Acoustic Disturbance (PCAD) working group, 
serum hormones were identified as possible indicators of behavioral 
effects that are translated into altered rates of reproduction and 
mortality. The Office of Naval Research hosted a workshop (Effects of 
Stress on Marine Mammals Exposed to Sound) in 2009 that focused on this 
very topic (ONR, 2009).
    Studies of other marine animals and terrestrial animals would also 
lead us to expect some marine mammals to experience physiological 
stress responses and, perhaps, physiological responses that would be 
classified as ``distress'' upon exposure to high frequency, mid-
frequency and low-frequency sounds. For example, Jansen (1998) reported 
on the relationship between acoustic exposures and physiological 
responses that are indicative of stress responses in humans (for 
example, elevated respiration and increased heart rates). Jones (1998) 
reported on reductions in human performance when faced with acute, 
repetitive exposures to acoustic disturbance. Trimper et al. (1998) 
reported on the physiological stress responses of osprey to low-level 
aircraft noise while Krausman et al. (2004) reported on the auditory 
and physiology stress responses of endangered Sonoran pronghorn to 
military overflights. Smith et al. (2004a, 2004b), for example, 
identified noise-induced physiological transient stress responses in 
hearing-specialist fish (i.e., goldfish) that accompanied short- and 
long-term hearing losses. Welch and Welch (1970) reported physiological 
and behavioral stress responses that accompanied damage to the inner 
ears of fish and several mammals.
    Hearing is one of the primary senses marine mammals use to gather 
information about their environment and to communicate with 
conspecifics. Although empirical information on the relationship 
between sensory impairment (TTS, PTS, and acoustic masking) on marine 
mammals remains limited, it seems reasonable to assume that reducing an 
animal's ability to gather information about its environment and to 
communicate with other members of its species would be stressful for 
animals that use hearing as their primary sensory mechanism. Therefore, 
we assume that acoustic exposures sufficient to trigger onset PTS or 
TTS would be accompanied by physiological stress responses because 
terrestrial animals exhibit those responses under similar conditions 
(NRC, 2003). More importantly, marine mammals might experience stress 
responses at received levels lower than those necessary to trigger 
onset TTS. Based on empirical studies of the time required to recover 
from stress responses (Moberg, 2000), we also assume that stress 
responses are likely to persist beyond the time interval required for 
animals to recover from TTS and might result in pathological and pre-
pathological states that would be as significant as behavioral 
responses to TTS.

Behavioral Disturbance

    Behavioral responses to sound are highly variable and context-
specific. Many different variables can influence an animal's perception 
of and response to (nature and magnitude) an acoustic event. An 
animal's prior experience with a sound or sound source effects whether 
it is less likely (habituation) or more likely (sensitization) to 
respond to certain sounds in the future (animals can also be innately 
pre-disposed to respond to certain sounds in certain ways) (Southall et 
al., 2007). Related to the sound itself, the perceived nearness of the 
sound, bearing of the sound (approaching vs. retreating), similarity of 
a sound to biologically relevant sounds in the animal's environment 
(i.e., calls of predators, prey, or conspecifics), and familiarity of 
the sound may affect the way an animal responds to the sound (Southall 
et al., 2007). Individuals (of different age, gender, reproductive 
status, etc.) among most populations will have variable hearing 
capabilities, and differing behavioral sensitivities to sounds that 
will be affected by prior conditioning, experience, and current 
activities of those individuals. Often, specific acoustic features of 
the sound and contextual variables (i.e., proximity, duration, or 
recurrence of the sound or the current behavior that the marine mammal 
is engaged in or its prior experience), as well as entirely separate 
factors such as the physical presence of a nearby vessel, may be more 
relevant to the animal's response than the received level alone.
    Exposure of marine mammals to sound sources can result in no 
response or responses including, but not limited to: increased 
alertness; orientation or attraction to a sound source; vocal 
modifications; cessation of feeding;

[[Page 7001]]

cessation of social interaction; alteration of movement or diving 
behavior; habitat abandonment (temporary or permanent); and, in severe 
cases, panic, flight, stampede, or stranding, potentially resulting in 
death (Southall et al., 2007). A review of marine mammal responses to 
anthropogenic sound was first conducted by Richardson and others in 
1995. A more recent review (Nowacek et al., 2007) addresses studies 
conducted since 1995 and focuses on observations where the received 
sound level of the exposed marine mammal(s) was known or could be 
estimated. The following sub-sections provide examples of behavioral 
responses that provide an idea of the variability in behavioral 
responses that would be expected given the differential sensitivities 
of marine mammal species to sound and the wide range of potential 
acoustic sources to which a marine mammal may be exposed. Estimates of 
the types of behavioral responses that could occur for a given sound 
exposure should be determined from the literature that is available for 
each species, or extrapolated from closely related species when no 
information exists.
    Flight Response--A flight response is a dramatic change in normal 
movement to a directed and rapid movement away from the perceived 
location of a sound source. Relatively little information on flight 
responses of marine mammals to anthropogenic signals exist, although 
observations of flight responses to the presence of predators have 
occurred (Connor and Heithaus, 1996). Flight responses have been 
speculated as being a component of marine mammal strandings associated 
with sonar activities (Evans and England, 2001).
    Response to Predator--Evidence suggests that at least some marine 
mammals have the ability to acoustically identify potential predators. 
For example, harbor seals that reside in the coastal waters off British 
Columbia are frequently targeted by certain groups of killer whales, 
but not others. The seals discriminate between the calls of threatening 
and non-threatening killer whales (Deecke et al., 2002), a capability 
that should increase survivorship while reducing the energy required 
for attending to and responding to all killer whale calls. The 
occurrence of masking or hearing impairment provides a means by which 
marine mammals may be prevented from responding to the acoustic cues 
produced by their predators. Whether or not this is a possibility 
depends on the duration of the masking/hearing impairment and the 
likelihood of encountering a predator during the time that predator 
cues are impeded.
    Diving--Changes in dive behavior can vary widely. They may consist 
of increased or decreased dive times and surface intervals as well as 
changes in the rates of ascent and descent during a dive. Variations in 
dive behavior may reflect interruptions in biologically significant 
activities (e.g., foraging) or they may be of little biological 
significance. Variations in dive behavior may also expose an animal to 
potentially harmful conditions (e.g., increasing the chance of ship-
strike) or may serve as an avoidance response that enhances 
survivorship. The impact of a variation in diving resulting from an 
acoustic exposure depends on what the animal is doing at the time of 
the exposure and the type and magnitude of the response.
    Nowacek et al. (2004) reported disruptions of dive behaviors in 
foraging North Atlantic right whales when exposed to an alerting 
stimulus, an action, they noted, that could lead to an increased 
likelihood of ship strike. However, the whales did not respond to 
playbacks of either right whale social sounds or vessel noise, 
highlighting the importance of the sound characteristics in producing a 
behavioral reaction. Conversely, Indo-Pacific humpback dolphins have 
been observed to dive for longer periods of time in areas where vessels 
were present and/or approaching (Ng and Leung, 2003). In both of these 
studies, the influence of the sound exposure cannot be decoupled from 
the physical presence of a surface vessel, thus complicating 
interpretations of the relative contribution of each stimulus to the 
response. Indeed, the presence of surface vessels, their approach, and 
speed of approach, seemed to be significant factors in the response of 
the Indo-Pacific humpback dolphins (Ng and Leung, 2003). Low frequency 
signals of the Acoustic Thermometry of Ocean Climate (ATOC) sound 
source were not found to affect dive times of humpback whales in 
Hawaiian waters (Frankel and Clark, 2000) or to overtly affect elephant 
seal dives (Costa et al., 2003). They did, however, produce subtle 
effects that varied in direction and degree among the individual seals, 
illustrating the equivocal nature of behavioral effects and consequent 
difficulty in defining and predicting them.
    Due to past incidents of beaked whale strandings associated with 
sonar operations, feedback paths are provided between avoidance and 
diving and indirect tissue effects. This feedback accounts for the 
hypothesis that variations in diving behavior and/or avoidance 
responses can possibly result in nitrogen tissue supersaturation and 
nitrogen off-gassing, possibly to the point of deleterious vascular 
bubble formation (Jepson et al., 2003). Although hypothetical, 
discussions surrounding this potential process are controversial.
    Foraging--Disruption of feeding behavior can be difficult to 
correlate with anthropogenic sound exposure, so it is usually inferred 
by observed displacement from known foraging areas, the appearance of 
secondary indicators (e.g., bubble nets or sediment plumes), or changes 
in dive behavior. Noise from seismic surveys was not found to impact 
the feeding behavior in western grey whales off the coast of Russia 
(Yazvenko et al., 2007) and sperm whales engaged in foraging dives did 
not abandon dives when exposed to distant signatures of seismic airguns 
(Madsen et al., 2006). Balaenopterid whales exposed to moderate low-
frequency signals similar to the ATOC sound source demonstrated no 
variation in foraging activity (Croll et al., 2001), whereas five out 
of six North Atlantic right whales exposed to an acoustic alarm 
interrupted their foraging dives (Nowacek et al., 2004). Although the 
received sound pressure levels were similar in the latter two studies, 
the frequency, duration, and temporal pattern of signal presentation 
were different. These factors, as well as differences in species 
sensitivity, are likely contributing factors to the differential 
response. A determination of whether foraging disruptions incur fitness 
consequences will require information on or estimates of the energetic 
requirements of the individuals and the relationship between prey 
availability, foraging effort and success, and the life history stage 
of the animal.
    Breathing--Variations in respiration naturally vary with different 
behaviors and variations in respiration rate as a function of acoustic 
exposure can be expected to co-occur with other behavioral reactions, 
such as a flight response or an alteration in diving. However, 
respiration rates in and of themselves may be representative of 
annoyance or an acute stress response. Mean exhalation rates of gray 
whales at rest and while diving were found to be unaffected by seismic 
surveys conducted adjacent to the whale feeding grounds (Gailey et al., 
2007). Studies with captive harbor porpoises showed increased 
respiration rates upon introduction of acoustic alarms (Kastelein et 
al., 2001; Kastelein et al., 2006a) and emissions for underwater data 
transmission (Kastelein et al., 2005). However, exposure of the same

[[Page 7002]]

acoustic alarm to a striped dolphin under the same conditions did not 
elicit a response (Kastelein et al., 2006a), again highlighting the 
importance in understanding species differences in the tolerance of 
underwater noise when determining the potential for impacts resulting 
from anthropogenic sound exposure.
    Social relationships--Social interactions between mammals can be 
affected by noise via the disruption of communication signals or by the 
displacement of individuals. Disruption of social relationships 
therefore depends on the disruption of other behaviors (e.g., caused 
avoidance, masking, etc.) and no specific overview is provided here. 
However, social disruptions must be considered in context of the 
relationships that are affected. Long-term disruptions of mother/calf 
pairs or mating displays have the potential to affect the growth and 
survival or reproductive effort/success of individuals, respectively.
    Vocalizations (also see Masking Section)--Vocal changes in response 
to anthropogenic noise can occur across the repertoire of sound 
production modes used by marine mammals, such as whistling, 
echolocation click production, calling, and singing. Changes may result 
in response to a need to compete with an increase in background noise 
or may reflect an increased vigilance or startle response. For example, 
in the presence of low-frequency active sonar, humpback whales have 
been observed to increase the length of their ``songs'' (Miller et al., 
2000; Fristrup et al., 2003), possibly due to the overlap in 
frequencies between the whale song and the low-frequency active sonar. 
A similar compensatory effect for the presence of low-frequency vessel 
noise has been suggested for right whales; right whales have been 
observed to shift the frequency content of their calls upward while 
reducing the rate of calling in areas of increased anthropogenic noise 
(Parks et al., 2007). Killer whales off the northwestern coast of the 
U.S. have been observed to increase the duration of primary calls once 
a threshold in observing vessel density (e.g., whale watching) was 
reached, which has been suggested as a response to increased masking 
noise produced by the vessels (Foote et al., 2004). In contrast, both 
sperm and pilot whales potentially ceased sound production during the 
Heard Island feasibility test (Bowles et al., 1994), although it cannot 
be absolutely determined whether the inability to acoustically detect 
the animals was due to the cessation of sound production or the 
displacement of animals from the area.
    Avoidance--Avoidance is the displacement of an individual from an 
area as a result of the presence of a sound. Richardson et al., (1995) 
noted that avoidance reactions are the most obvious manifestations of 
disturbance in marine mammals. It is qualitatively different from the 
flight response, but also differs in the magnitude of the response 
(i.e., directed movement, rate of travel, etc.). Oftentimes avoidance 
is temporary, and animals return to the area once the noise has ceased. 
Longer term displacement is possible, however, which can lead to 
changes in abundance or distribution patterns of the species in the 
affected region if they do not become acclimated to the presence of the 
sound (Blackwell et al., 2004; Bejder et al., 2006; Teilmann et al., 
2006). Acute avoidance responses have been observed in captive 
porpoises and pinnipeds exposed to a number of different sound sources 
(Kastelein et al., 2001; Finneran et al., 2003; Kastelein et al., 
2006a; Kastelein et al., 2006b). Short-term avoidance of seismic 
surveys, low frequency emissions, and acoustic deterrents have also 
been noted in wild populations of odontocetes (Bowles et al., 1994; 
Goold, 1996; 1998; Stone et al., 2000; Morton and Symonds, 2002) and to 
some extent in mysticetes (Gailey et al., 2007), while longer term or 
repetitive/chronic displacement for some dolphin groups and for 
manatees has been suggested to be due to the presence of chronic vessel 
noise (Haviland-Howell et al., 2007; Miksis-Olds et al., 2007).
    Maybaum (1993) conducted sound playback experiments to assess the 
effects of MFAS on humpback whales in Hawaiian waters. Specifically, 
she exposed focal pods to sounds of a 3.3-kHz sonar pulse, a sonar 
frequency sweep from 3.1 to 3.6 kHz, and a control (blank) tape while 
monitoring behavior, movement, and underwater vocalizations. The two 
types of sonar signals (which both contained mid- and low-frequency 
components) differed in their effects on the humpback whales, but both 
resulted in avoidance behavior. The whales responded to the pulse by 
increasing their distance from the sound source and responded to the 
frequency sweep by increasing their swimming speeds and track 
linearity. In the Caribbean, sperm whales avoided exposure to mid-
frequency submarine sonar pulses, in the range of 1000 Hz to 10,000 Hz 
(IWC 2005).
    Kvadsheim et al., (2007) conducted a controlled exposure experiment 
in which killer whales fitted with D-tags were exposed to mid-frequency 
active sonar (Source A: a 1.0 second upsweep 209 dB @ 1-2 kHz every 10 
seconds for 10 minutes; Source B: with a 1.0 second upsweep 197 dB @ 6-
7 kHz every 10 seconds for 10 minutes). When exposed to Source A, a 
tagged whale and the group it was traveling with did not appear to 
avoid the source. When exposed to Source B, the tagged whales along 
with other whales that had been carousel feeding, ceased feeding during 
the approach of the sonar and moved rapidly away from the source. When 
exposed to Source B, Kvadsheim and his co-workers reported that a 
tagged killer whale seemed to try to avoid further exposure to the 
sound field by the following behaviors: immediately swimming away 
(horizontally) from the source of the sound; engaging in a series of 
erratic and frequently deep dives that seemed to take it below the 
sound field; or swimming away while engaged in a series of erratic and 
frequently deep dives. Although the sample sizes in this study are too 
small to support statistical analysis, the behavioral responses of the 
orcas were consistent with the results of other studies.
    In 2007, the first in a series of behavioral response studies, a 
collaboration by the Navy, NMFS, and other scientists showed one beaked 
whale (Mesoplodon densirostris) responding to an MFAS playback. Tyack 
et al. (2011) indicates that the playback began when the tagged beaked 
whale was vocalizing at depth (at the deepest part of a typical feeding 
dive), following a previous control with no sound exposure. The whale 
appeared to stop clicking significantly earlier than usual, when 
exposed to mid-frequency signals in the 130-140 dB (rms) received level 
range. After a few more minutes of the playback, when the received 
level reached a maximum of 140-150 dB, the whale ascended on the slow 
side of normal ascent rates with a longer than normal ascent, at which 
point the exposure was terminated. The results are from a single 
experiment and a greater sample size is needed before robust and 
definitive conclusions can be drawn.
    Tyack et al. (2011) also indicates that Blainville's beaked 
whales--a resident species within the study area--appear to be 
sensitive to noise at levels well below expected TTS (~160 dB 
re1[micro]Pa). This sensitivity is manifest by an adaptive movement 
away from a sound source. This response was observed irrespective of 
whether the signal transmitted was within the band width of MFAS, which 
suggests that beaked whales may not respond to the specific sound 
signatures. Instead, they may be sensitive to any pulsed sound from a

[[Page 7003]]

point source in this frequency range. The response to such stimuli 
appears to involve maximizing the distance from the sound source.
    Results from a 2007-2008 study conducted near the Bahamas showed a 
change in diving behavior of an adult Blainville's beaked whale to 
playback of mid-frequency source and predator sounds (Boyd et al., 
2008; Tyack et al., 2011). Reaction to mid-frequency sounds included 
premature cessation of clicking and termination of a foraging dive, and 
a slower ascent rate to the surface. Preliminary results from a similar 
behavioral response study in southern California waters have been 
presented for the 2010-2011 field season (Southall et al., 2011). 
Cuvier's beaked whale responses suggested particular sensitivity to 
sound exposure as consistent with results for Blainville's beaked 
whale. Similarly, beaked whales exposed to sonar during British 
training exercises stopped foraging (DSTL 2007), and preliminary 
results of controlled playback of sonar may indicate feeding/foraging 
disruption of killer whales and sperm whales (Miller et al., 2011).
    Orientation--A shift in an animal's resting state or an attentional 
change via an orienting response represent behaviors that would be 
considered mild disruptions if occurring alone. As previously 
mentioned, the responses may co-occur with other behaviors; for 
instance, an animal may initially orient toward a sound source, and 
then move away from it. Thus, any orienting response should be 
considered in context of other reactions that may occur.
    There are few empirical studies of avoidance responses of free-
living cetaceans to MFAS. Much more information is available on the 
avoidance responses of free-living cetaceans to other acoustic sources, 
such as seismic airguns and low-frequency tactical sonar, than MFAS.

Behavioral Responses

    Southall et al. (2007) reports the results of the efforts of a 
panel of experts in acoustic research from behavioral, physiological, 
and physical disciplines that convened and reviewed the available 
literature on marine mammal hearing and physiological and behavioral 
responses to human-made sound with the goal of proposing exposure 
criteria for certain effects. This peer-reviewed compilation of 
literature is very valuable, though Southall et al. (2007) note that 
not all data are equal, some have poor statistical power, insufficient 
controls, and/or limited information on received levels, background 
noise, and other potentially important contextual variables--such data 
were reviewed and sometimes used for qualitative illustration but were 
not included in the quantitative analysis for the criteria 
recommendations. All of the studies considered, however, contain an 
estimate of the received sound level when the animal exhibited the 
indicated response.
    In the Southall et al. (2007) publication, for the purposes of 
analyzing responses of marine mammals to anthropogenic sound and 
developing criteria, the authors differentiate between single pulse 
sounds, multiple pulse sounds, and non-pulse sounds. MFAS/HFAS sonar is 
considered a non-pulse sound. Southall et al. (2007) summarize the 
studies associated with low-frequency, mid-frequency, and high-
frequency cetacean and pinniped responses to non-pulse sounds, based 
strictly on received level, in Appendix C of their article 
(incorporated by reference and summarized in the three paragraphs 
below).
    The studies that address responses of low-frequency cetaceans to 
non-pulse sounds include data gathered in the field and related to 
several types of sound sources (of varying similarity to MFAS/HFAS) 
including: vessel noise, drilling and machinery playback, low-frequency 
M-sequences (sine wave with multiple phase reversals) playback, 
tactical low-frequency active sonar playback, drill ships, Acoustic 
Thermometry of Ocean Climate (ATOC) source, and non-pulse playbacks. 
These studies generally indicate no (or very limited) responses to 
received levels in the 90 to 120 dB re: 1 [micro]Pa range and an 
increasing likelihood of avoidance and other behavioral effects in the 
120 to 160 dB range. As mentioned earlier, though, contextual variables 
play a very important role in the reported responses and the severity 
of effects are not linear when compared to received level. Also, few of 
the laboratory or field datasets had common conditions, behavioral 
contexts or sound sources, so it is not surprising that responses 
differ.
    The studies that address responses of mid-frequency cetaceans to 
non-pulse sounds include data gathered both in the field and the 
laboratory and related to several different sound sources (of varying 
similarity to MFAS/HFAS) including: pingers, drilling playbacks, ship 
and ice-breaking noise, vessel noise, Acoustic Harassment Devices 
(AHDs), Acoustic Deterrent Devices (ADDs), MFAS, and non-pulse bands 
and tones. Southall et al. (2007) were unable to come to a clear 
conclusion regarding the results of these studies. In some cases, 
animals in the field showed significant responses to received levels 
between 90 and 120 dB, while in other cases these responses were not 
seen in the 120 to 150 dB range. The disparity in results was likely 
due to contextual variation and the differences between the results in 
the field and laboratory data (animals typically responded at lower 
levels in the field).
    The studies that address responses of high frequency cetaceans to 
non-pulse sounds include data gathered both in the field and the 
laboratory and related to several different sound sources (of varying 
similarity to MFAS/HFAS) including: pingers, AHDs, and various 
laboratory non-pulse sounds. All of these data were collected from 
harbor porpoises. Southall et al. (2007) concluded that the existing 
data indicate that harbor porpoises are likely sensitive to a wide 
range of anthropogenic sounds at low received levels (~ 90 to 120 dB), 
at least for initial exposures. All recorded exposures above 140 dB 
induced profound and sustained avoidance behavior in wild harbor 
porpoises (Southall et al., 2007). Rapid habituation was noted in some 
but not all studies. There is no data to indicate whether other high 
frequency cetaceans are as sensitive to anthropogenic sound as harbor 
porpoises are.
    The studies that address the responses of pinnipeds in water to 
non-pulse sounds include data gathered both in the field and the 
laboratory and related to several different sound sources (of varying 
similarity to MFAS/HFAS) including: AHDs, ATOC, various non-pulse 
sounds used in underwater data communication; underwater drilling, and 
construction noise. Few studies exist with enough information to 
include them in the analysis. The limited data suggested that exposures 
to non-pulse sounds between 90 and 140 dB generally do not result in 
strong behavioral responses in pinnipeds in water, but no data exist at 
higher received levels.
    In addition to summarizing the available data, the authors of 
Southall et al. (2007) developed a severity scaling system with the 
intent of ultimately being able to assign some level of biological 
significance to a response. Following is a summary of their scoring 
system; a comprehensive list of the behaviors associated with each 
score, along with the assigned scores, may be found in the report:
     0-3 (Minor and/or brief behaviors) includes, but is not 
limited to: no response; minor changes in speed or locomotion (but with 
no avoidance); individual alert behavior; minor cessation in vocal 
behavior; minor

[[Page 7004]]

changes in response to trained behaviors (in laboratory)
     4-6 (Behaviors with higher potential to affect foraging, 
reproduction, or survival) includes, but is not limited to: moderate 
changes in speed, direction, or dive profile; brief shift in group 
distribution; prolonged cessation or modification of vocal behavior 
(duration > duration of sound), minor or moderate individual and/or 
group avoidance of sound; brief cessation of reproductive behavior; or 
refusal to initiate trained tasks (in laboratory)
     7-9 (Behaviors considered likely to affect the 
aforementioned vital rates) includes, but is not limited to: extensive 
or prolonged aggressive behavior; moderate, prolonged or significant 
separation of females and dependent offspring with disruption of 
acoustic reunion mechanisms; long-term avoidance of an area; outright 
panic, stampede, stranding; threatening or attacking sound source (in 
laboratory)

Potential Effects of Behavioral Disturbance

    The different ways that marine mammals respond to sound are 
sometimes indicators of the ultimate effect that exposure to a given 
stimulus will have on the well-being (survival, reproduction, etc.) of 
an animal. There is little marine mammal data quantitatively relating 
the exposure of marine mammals to sound to effects on reproduction or 
survival, though data exists for terrestrial species to which we can 
draw comparisons for marine mammals.
    Attention is the cognitive process of selectively concentrating on 
one aspect of an animal's environment while ignoring other things 
(Posner, 1994). Because animals (including humans) have limited 
cognitive resources, there is a limit to how much sensory information 
they can process at any time. The phenomenon called ``attentional 
capture'' occurs when a stimulus (usually a stimulus that an animal is 
not concentrating on or attending to) ``captures'' an animal's 
attention. This shift in attention can occur consciously or 
subconsciously (for example, when an animal hears sounds that it 
associates with the approach of a predator) and the shift in attention 
can be sudden (Dukas, 2002; van Rij, 2007). Once a stimulus has 
captured an animal's attention, the animal can respond by ignoring the 
stimulus, assuming a ``watch and wait'' posture, or treat the stimulus 
as a disturbance and respond accordingly, which includes scanning for 
the source of the stimulus or ``vigilance'' (Cowlishaw et al., 2004).
    Vigilance is normally an adaptive behavior that helps animals 
determine the presence or absence of predators, assess their distance 
from conspecifics, or to attend cues from prey (Bednekoff and Lima, 
1998; Treves, 2000). Despite those benefits, however, vigilance has a 
cost of time; when animals focus their attention on specific 
environmental cues, they are not attending to other activities such as 
foraging. These costs have been documented best in foraging animals, 
where vigilance has been shown to substantially reduce feeding rates 
(Saino, 1994; Beauchamp and Livoreil, 1997; Fritz et al., 2002). 
Animals will spend more time being vigilant, which may translate to 
less time foraging or resting, when disturbance stimuli approach them 
more directly, remain at closer distances, have a greater group size 
(for example, multiple surface vessels), or when they co-occur with 
times that an animal perceives increased risk (for example, when they 
are giving birth or accompanied by a calf). Most of the published 
literature, however, suggests that direct approaches will increase the 
amount of time animals will dedicate to being vigilant. For example, 
bighorn sheep and Dall's sheep dedicated more time being vigilant, and 
less time resting or foraging, when aircraft made direct approaches 
over them (Frid, 2001; Stockwell et al., 1991).
    Several authors have established that long-term and intense 
disturbance stimuli can cause population declines by reducing the body 
condition of individuals that have been disturbed, followed by reduced 
reproductive success, reduced survival, or both (Daan et al., 1996; 
Madsen, 1994; White, 1983). For example, Madsen (1994) reported that 
pink-footed geese in undisturbed habitat gained body mass and had about 
a 46-percent reproductive success rate compared with geese in disturbed 
habitat (being consistently scared off the fields on which they were 
foraging) which did not gain mass and had a 17-percent reproductive 
success rate. Similar reductions in reproductive success have been 
reported for mule deer disturbed by all-terrain vehicles (Yarmoloy et 
al., 1988), caribou disturbed by seismic exploration blasts (Bradshaw 
et al., 1998), caribou disturbed by low-elevation military jet-fights 
(Luick et al., 1996), and caribou disturbed by low-elevation jet 
flights (Harrington and Veitch, 1992). Similarly, a study of elk that 
were disturbed experimentally by pedestrians concluded that the ratio 
of young to mothers was inversely related to disturbance rate (Phillips 
and Alldredge, 2000).
    The primary mechanism by which increased vigilance and disturbance 
appear to affect the fitness of individual animals is by disrupting an 
animal's time budget and, as a result, reducing the time they might 
spend foraging and resting (which increases an animal's activity rate 
and energy demand). For example, a study of grizzly bears reported that 
bears disturbed by hikers reduced their energy intake by an average of 
12 kcal/minute (50.2 x 103kJ/minute), and spent energy 
fleeing or acting aggressively toward hikers (White et al. 1999). 
Alternately, Ridgway et al., (2006) reported that increased vigilance 
in bottlenose dolphins exposed to sound over a 5-day period did not 
cause any sleep deprivation or stress effects such as changes in 
cortisol or epinephrine levels.
    On a related note, many animals perform vital functions, such as 
feeding, resting, traveling, and socializing, on a diel cycle (24-hour 
cycle). Substantive behavioral reactions to noise exposure (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). Consequently, a behavioral response lasting less than 1 day and 
not recurring on subsequent days is not considered particularly severe 
unless it could directly affect reproduction or survival (Southall et 
al., 2007).
    In response to the National Research Council of the National 
Academies (2005) review, the Office of Naval Research founded a working 
group to formalize the Population Consequences of Acoustic Disturbance 
(PCAD) framework. The PCAD model connects observable data through a 
series of transfer functions using a case study approach. The long-term 
goal is to improve the understanding of how effects of sound on marine 
mammals transfer between behavior and life functions and between life 
functions and vital rates of individuals. Then, this understanding of 
how disturbance can affect the vital rates of individuals will 
facilitate the further assessment of the population level effects of 
anthropogenic sound on marine mammals by providing a quantitative 
approach to evaluate effects and the relationship between takes and 
possible changes to adult survival and/or annual recruitment.

Stranding and Mortality

    When a live or dead marine mammal swims or floats onto shore and 
becomes

[[Page 7005]]

``beached'' or incapable of returning to sea, the event is termed a 
``stranding'' (Geraci et al., 1999; Perrin and Geraci, 2002; Geraci and 
Lounsbury, 2005; NMFS, 2007). The legal definition for a stranding 
within the U.S. is that (A) ``a marine mammal is dead and is (i) on a 
beach or shore of the United States; or (ii) in waters under the 
jurisdiction of the United States (including any navigable waters); or 
(B) a marine mammal is alive and is (i) on a beach or shore of the 
United States and unable to return to the water; (ii) on a beach or 
shore of the United States and, although able to return to the water, 
is in need of apparent medical attention; or (iii) in the waters under 
the jurisdiction of the United States (including any navigable waters), 
but is unable to return to its natural habitat under its own power or 
without assistance.'' (16 U.S.C. 1421h).
    Marine mammals are known to strand for a variety of reasons, such 
as infectious agents, biotoxicosis, starvation, fishery interaction, 
ship strike, unusual oceanographic or weather events, sound exposure, 
or combinations of these stressors sustained concurrently or in series. 
However, the cause or causes of most strandings are unknown (Geraci et 
al., 1976; Eaton, 1979; Odell et al., 1980; Best, 1982). Numerous 
studies suggest that the physiology, behavior, habitat relationships, 
age, or condition of cetaceans may cause them to strand or might 
predispose them to strand when exposed to another phenomenon. These 
suggestions are consistent with the conclusions of numerous other 
studies that have demonstrated that combinations of dissimilar 
stressors commonly combine to kill an animal or dramatically reduce its 
fitness, even though one exposure without the other does not produce 
the same result (Chroussos, 2000; Creel, 2005; DeVries et al., 2003; 
Fair and Becker, 2000; Foley et al., 2001; Moberg, 2000; Relyea, 2005a, 
2005b; Romero, 2004; Sih et al., 2004). For reference, between 2001 and 
2009, there was an annual average of 1,400 cetacean strandings and 
4,300 pinniped strandings along the coasts of the continental U.S. and 
Alaska (NMFS, 2011).
    Several sources have published lists of mass stranding events of 
cetaceans in an attempt to identify relationships between those 
stranding events and military sonar (Hildebrand, 2004; IWC, 2005; 
Taylor et al., 2004). For example, based on a review of stranding 
records between 1960 and 1995, the International Whaling Commission 
(2005) identified ten mass stranding events of Cuvier's beaked whales 
had been reported and one mass stranding of four Baird's beaked whale. 
The IWC concluded that, out of eight stranding events reported from the 
mid-1980s to the summer of 2003, seven had been coincident with the use 
of tactical mid-frequency sonar, one of those seven had been associated 
with the use of tactical low-frequency sonar, and the remaining 
stranding event had been associated with the use of seismic airguns.
    Most of the stranding events reviewed by the International Whaling 
Commission involved beaked whales. A mass stranding of Cuvier's beaked 
whales in the eastern Mediterranean Sea occurred in 1996 (Frantzis, 
1998) and mass stranding events involving Gervais' beaked whales, 
Blainville's beaked whales, and Cuvier's beaked whales occurred off the 
coast of the Canary Islands in the late 1980s (Simmonds and Lopez-
Jurado, 1991). The stranding events that occurred in the Canary Islands 
and Kyparissiakos Gulf in the late 1990s and the Bahamas in 2000 have 
been the most intensively-studied mass stranding events and have been 
associated with naval maneuvers involving the use of tactical sonar.
    Between 1960 and 2006, 48 strandings (68 percent) involved beaked 
whales, three (4 percent) involved dolphins, and 14 (20 percent) 
involved whale species. Cuvier's beaked whales were involved in the 
greatest number of these events (48 or 68 percent), followed by sperm 
whales (seven or 10 percent), and Blainville's and Gervais' beaked 
whales (four each or 6 percent). Naval activities (not just activities 
conducted by the U.S. Navy) that might have involved active sonar are 
reported to have coincided with nine or 10 (13 to 14 percent) of those 
stranding events. Between the mid-1980s and 2003 (the period reported 
by the International Whaling Commission), we identified reports of 44 
mass cetacean stranding events of which at least seven were coincident 
with naval exercises that were using MFAS.

Strandings Associated With Impulse Sound

    During a Navy training event on March 4, 2011 at the Silver Strand 
Training Complex in San Diego, California, three or possibly four 
dolphins were killed in an explosion. During an underwater detonation 
training event, a pod of 100 to 150 long-beaked common dolphins were 
observed moving toward the 700-yd (640.1-m) exclusion zone around the 
explosive charge, monitored by personnel in a safety boat and 
participants in a dive boat. Approximately 5 minutes remained on a 
time-delay fuse connected to a single 8.76 lb (3.97 kg) explosive 
charge (C-4 and detonation cord). Although the dive boat was placed 
between the pod and the explosive in an effort to guide the dolphins 
away from the area, that effort was unsuccessful and three long-beaked 
common dolphins near the explosion died. In addition to the three 
dolphins found dead on March 4, the remains of a fourth dolphin were 
discovered on March 7, 2011 near Ocean Beach, California (3 days later 
and approximately 11.8 mi. [19 km] from Silver Strand where the 
training event occurred), which might also have been related to this 
event. Association of the fourth stranding with the training event is 
uncertain because dolphins strand on a regular basis in the San Diego 
area. Details such as the dolphins' depth and distance from the 
explosive at the time of the detonation could not be estimated from the 
250 yd (228.6 m) standoff point of the observers in the dive boat or 
the safety boat.
    These dolphin mortalities are the only known occurrence of a U.S. 
Navy training or testing event involving impulse energy (underwater 
detonation) that caused mortality or injury to a marine mammal. Despite 
this being a rare occurrence, the Navy has reviewed training 
requirements, safety procedures, and possible mitigation measures and 
implemented changes to reduce the potential for this to occur in the 
future. Discussions of procedures associated with these and other 
training and testing events are presented in the Mitigation section.

Strandings Associated With MFAS

    Over the past 16 years, there have been five stranding events 
coincident with military mid-frequency sonar use in which exposure to 
sonar is believed to have been a contributing factor: Greece (1996); 
the Bahamas (2000); Madeira (2000); Canary Islands (2002); and Spain 
(2006). Additionally, in 2004, during the Rim of the Pacific (RIMPAC) 
exercises, between 150 and 200 usually pelagic melon-headed whales 
occupied the shallow waters of Hanalei Bay, Kauai, Hawaii for over 28 
hours. NMFS determined that MFAS was a plausible, if not likely, 
contributing factor in what may have been a confluence of events that 
led to the stranding. A number of other stranding events coincident 
with the operation of mid-frequency sonar, including the death of 
beaked whales or other species (minke whales, dwarf sperm whales, pilot 
whales), have been reported; however, the majority have not been 
investigated to the degree necessary to determine the cause of the 
stranding and only one of these stranding events, the Bahamas (2000),

[[Page 7006]]

was associated with exercises conducted by the U.S. Navy.
    Greece (1996)--Twelve Cuvier's beaked whales stranded atypically 
(in both time and space) along a 38.2-km strand of the Kyparissiakos 
Gulf coast on May 12 and 13, 1996 (Frantzis, 1998). From May 11 through 
May 15, the North Atlantic Treaty Organization (NATO) research vessel 
Alliance was conducting sonar tests with signals of 600 Hz and 3 kHz 
and source levels of 228 and 226 dB re: 1[mu]Pa, respectively (D'Amico 
and Verboom, 1998; D'Spain et al., 2006). The timing and location of 
the testing encompassed the time and location of the strandings 
(Frantzis, 1998).
    Necropsies of eight of the animals were performed but were limited 
to basic external examination and sampling of stomach contents, blood, 
and skin. No ears or organs were collected, and no histological samples 
were preserved. No apparent abnormalities or wounds were found. 
Examination of photos of the animals, taken soon after their death, 
revealed that the eyes of at least four of the individuals were 
bleeding. Photos were taken soon after their death (Frantzis, 2004). 
Stomach contents contained the flesh of cephalopods, indicating that 
feeding had recently taken place (Frantzis, 1998).
    All available information regarding the conditions associated with 
this stranding event were compiled, and many potential causes were 
examined including major pollution events, prominent tectonic activity, 
unusual physical or meteorological events, magnetic anomalies, 
epizootics, and conventional military activities (International Council 
for the Exploration of the Sea, 2005a). However, none of these 
potential causes coincided in time or space with the mass stranding, or 
could explain its characteristics (International Council for the 
Exploration of the Sea, 2005a). The robust condition of the animals, 
plus the recent stomach contents, is inconsistent with pathogenic 
causes. In addition, environmental causes can be ruled out as there 
were no unusual environmental circumstances or events before or during 
this time period and within the general proximity (Frantzis, 2004).
    Because of the rarity of this mass stranding of Cuvier's beaked 
whales in the Kyparissiakos Gulf (first one in history), the 
probability for the two events (the military exercises and the 
strandings) to coincide in time and location, while being independent 
of each other, was thought to be extremely low (Frantzis, 1998). 
However, because full necropsies had not been conducted, and no 
abnormalities were noted, the cause of the strandings could not be 
precisely determined (Cox et al., 2006). A Bioacoustics Panel convened 
by NATO concluded that the evidence available did not allow them to 
accept or reject sonar exposures as a causal agent in these stranding 
events. The analysis of this stranding event provided support for, but 
no clear evidence for, the cause-and-effect relationship of tactical 
sonar training activities and beaked whale strandings (Cox et al., 
2006).
    Bahamas (2000)--NMFS and the Navy prepared a joint report 
addressing the multi-species stranding in the Bahamas in 2000, which 
took place within 24 hours of U.S. Navy ships using MFAS as they passed 
through the Northeast and Northwest Providence Channels on March 15-16, 
2000. The ships, which operated both AN/SQS-53C and AN/SQS-56, moved 
through the channel while emitting sonar pings approximately every 24 
seconds. Of the 17 cetaceans that stranded over a 36-hr period 
(Cuvier's beaked whales, Blainville's beaked whales, minke whales, and 
a spotted dolphin), seven animals died on the beach (five Cuvier's 
beaked whales, one Blainville's beaked whale, and the spotted dolphin), 
while the other 10 were returned to the water alive (though their 
ultimate fate is unknown). As discussed in the Bahamas report (DOC/DON, 
2001), there is no likely association between the minke whale and 
spotted dolphin strandings and the operation of MFAS.
    Necropsies were performed on five of the stranded beaked whales. 
All five necropsied beaked whales were in good body condition, showing 
no signs of infection, disease, ship strike, blunt trauma, or fishery 
related injuries, and three still had food remains in their stomachs. 
Auditory structural damage was discovered in four of the whales, 
specifically bloody effusions or hemorrhaging around the ears. 
Bilateral intracochlear and unilateral temporal region subarachnoid 
hemorrhage, with blood clots in the lateral ventricles, were found in 
two of the whales. Three of the whales had small hemorrhages in their 
acoustic fats (located along the jaw and in the melon).
    A comprehensive investigation was conducted and all possible causes 
of the stranding event were considered, whether they seemed likely at 
the outset or not. Based on the way in which the strandings coincided 
with ongoing naval activity involving tactical MFAS use, in terms of 
both time and geography, the nature of the physiological effects 
experienced by the dead animals, and the absence of any other acoustic 
sources, the investigation team concluded that MFAS aboard U.S. Navy 
ships that were in use during the active sonar exercise in question 
were the most plausible source of this acoustic or impulse trauma to 
beaked whales. This sound source was active in a complex environment 
that included the presence of a surface duct, unusual and steep 
bathymetry, a constricted channel with limited egress, intensive use of 
multiple, active sonar units over an extended period of time, and the 
presence of beaked whales that appear to be sensitive to the 
frequencies produced by these active sonars. The investigation team 
concluded that the cause of this stranding event was the confluence of 
the Navy MFAS and these contributory factors working together, and 
further recommended that the Navy avoid operating MFAS in situations 
where these five factors would be likely to occur. This report does not 
conclude that all five of these factors must be present for a stranding 
to occur, nor that beaked whales are the only species that could 
potentially be affected by the confluence of the other factors. Based 
on this, NMFS believes that the operation of MFAS in situations where 
surface ducts exist, or in marine environments defined by steep 
bathymetry and/or constricted channels may increase the likelihood of 
producing a sound field with the potential to cause cetaceans 
(especially beaked whales) to strand, and therefore, suggests the need 
for increased vigilance while operating MFAS in these areas, especially 
when beaked whales (or potentially other deep divers) are likely 
present.
    Madeira, Spain (2000)--From May 10-14, 2000, three Cuvier's beaked 
whales were found atypically stranded on two islands in the Madeira 
archipelago, Portugal (Cox et al., 2006). A fourth animal was reported 
floating in the Madeiran waters by fisherman but did not come ashore 
(Woods Hole Oceanographic Institution, 2005). Joint NATO amphibious 
training peacekeeping exercises involving participants from 17 
countries 80 warships, took place in Portugal during May 2-15, 2000.
    The bodies of the three stranded whales were examined post mortem 
(Woods Hole Oceanographic Institution, 2005), though only one of the 
stranded whales was fresh enough (24 hours after stranding) to be 
necropsied (Cox et al., 2006). Results from the necropsy revealed 
evidence of hemorrhage and congestion in the right lung and both 
kidneys (Cox et al., 2006). There was also evidence of intercochlear 
and intracranial hemorrhage similar to that which was observed in the 
whales that

[[Page 7007]]

stranded in the Bahamas event (Cox et al., 2006). There were no signs 
of blunt trauma, and no major fractures (Woods Hole Oceanographic 
Institution, 2005).
    The cranial sinuses and airways were found to be clear with little 
or no fluid deposition, which may indicate good preservation of tissues 
(Woods Hole Oceanographic Institution, 2005).
    Several observations on the Madeira stranded beaked whales, such as 
the pattern of injury to the auditory system, are the same as those 
observed in the Bahamas strandings. Blood in and around the eyes, 
kidney lesions, pleural hemorrhages, and congestion in the lungs are 
particularly consistent with the pathologies from the whales stranded 
in the Bahamas, and are consistent with stress and pressure related 
trauma. The similarities in pathology and stranding patterns between 
these two events suggest that a similar pressure event may have 
precipitated or contributed to the strandings at both sites (Woods Hole 
Oceanographic Institution, 2005).
    Even though no definitive causal link can be made between the 
stranding event and naval exercises, certain conditions may have 
existed in the exercise area that, in their aggregate, may have 
contributed to the marine mammal strandings (Freitas, 2004): exercises 
were conducted in areas of at least 547 fathoms (1,000 m) depth near a 
shoreline where there is a rapid change in bathymetry on the order of 
547 to 3,281 fathoms (1,000 to 6,000 m) occurring across a relatively 
short horizontal distance (Freitas, 2004); multiple ships were 
operating around Madeira, though it is not known if MFAS was used, and 
the specifics of the sound sources used are unknown (Cox et al., 2006, 
Freitas, 2004); and exercises took place in an area surrounded by 
landmasses separated by less than 35 nm (65 km) and at least 10 nm (19 
km) in length, or in an embayment. Exercises involving multiple ships 
employing MFAS near land may produce sound directed towards a channel 
or embayment that may cut off the lines of egress for marine mammals 
(Freitas, 2004).
    Canary Islands, Spain (2002)--The southeastern area within the 
Canary Islands is well known for aggregations of beaked whales due to 
its ocean depths of greater than 547 fathoms (1,000 m) within a few 
hundred meters of the coastline (Fernandez et al., 2005). On September 
24, 2002, 14 beaked whales were found stranded on Fuerteventura and 
Lanzarote Islands in the Canary Islands (International Council for 
Exploration of the Sea, 2005a). Seven whales died, while the remaining 
seven live whales were returned to deeper waters (Fernandez et al., 
2005). Four beaked whales were found stranded dead over the next three 
days either on the coast or floating offshore. These strandings 
occurred within near proximity of an international naval exercise that 
utilized MFAS and involved numerous surface warships and several 
submarines. Strandings began about 4 hours after the onset of MFAS 
activity (International Council for Exploration of the Sea, 2005a; 
Fernandez et al., 2005).
    Eight Cuvier's beaked whales, one Blainville's beaked whale, and 
one Gervais' beaked whale were necropsied, six of them within 12 hours 
of stranding (Fernandez et al., 2005). No pathogenic bacteria were 
isolated from the carcasses (Jepson et al., 2003). The animals 
displayed severe vascular congestion and hemorrhage especially around 
the tissues in the jaw, ears, brain, and kidneys, displaying marked 
disseminated microvascular hemorrhages associated with widespread fat 
emboli (Jepson et al., 2003; International Council for Exploration of 
the Sea, 2005a). Several organs contained intravascular bubbles, 
although definitive evidence of gas embolism in vivo is difficult to 
determine after death (Jepson et al., 2003). The livers of the 
necropsied animals were the most consistently affected organ, which 
contained macroscopic gas-filled cavities and had variable degrees of 
fibrotic encapsulation. In some animals, cavitary lesions had 
extensively replaced the normal tissue (Jepson et al., 2003). Stomachs 
contained a large amount of fresh and undigested contents, suggesting a 
rapid onset of disease and death (Fernandez et al., 2005). Head and 
neck lymph nodes were enlarged and congested, and parasites were found 
in the kidneys of all animals (Fernandez et al., 2005).
    The association of NATO MFAS use close in space and time to the 
beaked whale strandings, and the similarity between this stranding 
event and previous beaked whale mass strandings coincident with sonar 
use, suggests that a similar scenario and causative mechanism of 
stranding may be shared between the events. Beaked whales stranded in 
this event demonstrated brain and auditory system injuries, 
hemorrhages, and congestion in multiple organs, similar to the 
pathological findings of the Bahamas and Madeira stranding events. In 
addition, the necropsy results of Canary Islands stranding event lead 
to the hypothesis that the presence of disseminated and widespread gas 
bubbles and fat emboli were indicative of nitrogen bubble formation, 
similar to what might be expected in decompression sickness (Jepson et 
al., 2003; Fern[aacute]ndez et al., 2005).
    Hanalei Bay (2004)--On July 3 and 4, 2004, approximately 150 to 200 
melon-headed whales occupied the shallow waters of the Hanalei Bay, 
Kaua'i, Hawaii for over 28 hrs. Attendees of a canoe blessing observed 
the animals entering the Bay in a single wave formation at 7 a.m. on 
July 3, 2004. The animals were observed moving back into the shore from 
the mouth of the Bay at 9 a.m. The usually pelagic animals milled in 
the shallow bay and were returned to deeper water with human assistance 
beginning at 9:30 a.m. on July 4, 2004, and were out of sight by 10:30 
a.m.
    Only one animal, a calf, was known to have died following this 
event. The animal was noted alive and alone in the Bay on the afternoon 
of July 4, 2004, and was found dead in the Bay the morning of July 5, 
2004. A full necropsy, magnetic resonance imaging, and computerized 
tomography examination were performed on the calf to determine the 
manner and cause of death. The combination of imaging, necropsy and 
histological analyses found no evidence of infectious, internal 
traumatic, congenital, or toxic factors. Cause of death could not be 
definitively determined, but it is likely that maternal separation, 
poor nutritional condition, and dehydration contributed to the final 
demise of the animal. Although we do not know when the calf was 
separated from its mother, the animals' movement into the Bay and 
subsequent milling and re-grouping may have contributed to the 
separation or lack of nursing, especially if the maternal bond was weak 
or this was an inexperienced mother with her first calf.
    Environmental factors, abiotic and biotic, were analyzed for any 
anomalous occurrences that would have contributed to the animals 
entering and remaining in Hanalei Bay. The Bay's bathymetry is similar 
to many other sites within the Hawaiian Island chain and dissimilar to 
sites that have been associated with mass strandings in other parts of 
the U.S. The weather conditions appeared to be normal for that time of 
year with no fronts or other significant features noted. There was no 
evidence of unusual distribution, occurrence of predator or prey 
species, or unusual harmful algal blooms, although Mobley et al., 2007 
suggested that the full moon cycle that occurred at that time may have 
influenced a run of squid into the Bay. Weather patterns and bathymetry 
that have been associated with mass

[[Page 7008]]

strandings elsewhere were not found to occur in this instance.
    The Hanalei event was spatially and temporally correlated with 
RIMPAC. Official sonar training and tracking exercises in the Pacific 
Missile Range Facility (PMRF) warning area did not commence until 
approximately 8 a.m. on July 3 and were thus ruled out as a possible 
trigger for the initial movement into the Bay. However, six naval 
surface vessels transiting to the operational area on July 2 
intermittently transmitted active sonar (for approximately 9 hours 
total from 1:15 p.m. to 12:30 a.m.) as they approached from the south. 
The potential for these transmissions to have triggered the whales' 
movement into Hanalei Bay was investigated. Analyses with the 
information available indicated that animals to the south and east of 
Kaua'i could have detected active sonar transmissions on July 2, and 
reached Hanalei Bay on or before 7 a.m. on July 3. However, data 
limitations regarding the position of the whales prior to their arrival 
in the Bay, the magnitude of sonar exposure, behavioral responses of 
melon-headed whales to acoustic stimuli, and other possible relevant 
factors preclude a conclusive finding regarding the role of sonar in 
triggering this event. Propagation modeling suggests that transmissions 
from sonar use during the July 3 exercise in the PMRF warning area may 
have been detectable at the mouth of the Bay. If the animals responded 
negatively to these signals, it may have contributed to their continued 
presence in the Bay. The U.S. Navy ceased all active sonar 
transmissions during exercises in this range on the afternoon of July 
3. Subsequent to the cessation of sonar use, the animals were herded 
out of the Bay.
    While causation of this stranding event may never be unequivocally 
determined, we consider the active sonar transmissions of July 2-3, 
2004, a plausible, if not likely, contributing factor in what may have 
been a confluence of events. This conclusion is based on the following: 
(1) The evidently anomalous nature of the stranding; (2) its close 
spatiotemporal correlation with wide-scale, sustained use of sonar 
systems previously associated with stranding of deep-diving marine 
mammals; (3) the directed movement of two groups of transmitting 
vessels toward the southeast and southwest coast of Kauai; (4) the 
results of acoustic propagation modeling and an analysis of possible 
animal transit times to the Bay; and (5) the absence of any other 
compelling causative explanation. The initiation and persistence of 
this event may have resulted from an interaction of biological and 
physical factors. The biological factors may have included the presence 
of an apparently uncommon, deep-diving cetacean species (and possibly 
an offshore, non-resident group), social interactions among the animals 
before or after they entered the Bay, and/or unknown predator or prey 
conditions. The physical factors may have included the presence of 
nearby deep water, multiple vessels transiting in a directed manner 
while transmitting active sonar over a sustained period, the presence 
of surface sound ducting conditions, and/or intermittent and random 
human interactions while the animals were in the Bay.
    A separate event involving melon-headed whales and rough-toothed 
dolphins took place over the same period of time in the Northern 
Mariana Islands (Jefferson et al., 2006), which is several thousand 
miles from Hawaii. Some 500 to 700 melon-headed whales came into 
Sasanhaya Bay on July 4, 2004, near the island of Rota and then left of 
their own accord after 5.5 hours; no known active sonar transmissions 
occurred in the vicinity of that event. The Rota incident led to 
scientific debate regarding what, if any, relationship the event had to 
the simultaneous events in Hawaii and whether they might be related by 
some common factor (e.g., there was a full moon on July 2, 2004, as 
well as during other melon-headed whale strandings and nearshore 
aggregations (Brownell et al., 2009; Lignon et al., 2007; Mobley et 
al., 2007). Brownell et al. (2009) compared the two incidents, along 
with one other stranding incident at Nuka Hiva in French Polynesia and 
normal resting behaviors observed at Palmyra Island, in regard to 
physical features in the areas, melon-headed whale behavior, and lunar 
cycles. Brownell et al., (2009) concluded that the rapid entry of the 
whales into Hanalei Bay, their movement into very shallow water far 
from the 100-m contour, their milling behavior (typical pre-stranding 
behavior), and their reluctance to leave the bay constituted an unusual 
event that was not similar to the events that occurred at Rota (but was 
similar to the events at Palmyra), which appear to be similar to 
observations of melon-headed whales resting normally at Palmyra Island. 
Additionally, there was no correlation between lunar cycle and the 
types of behaviors observed in the Brownell et al. (2009) examples.
    Spain (2006)--The Spanish Cetacean Society reported an atypical 
mass stranding of four beaked whales that occurred January 26, 2006, on 
the southeast coast of Spain, near Mojacar (Gulf of Vera) in the 
Western Mediterranean Sea. According to the report, two of the whales 
were discovered the evening of January 26 and were found to be still 
alive. Two other whales were discovered during the day on January 27, 
but had already died. The first three animals were located near the 
town of Mojacar and the fourth animal was found dead, a few kilometers 
north of the first three animals. From January 25-26, 2006, Standing 
NATO Response Force Maritime Group Two (five of seven ships including 
one U.S. ship under NATO Operational Control) had conducted active 
sonar training against a Spanish submarine within 50 nm (93 km) of the 
stranding site.
    Veterinary pathologists necropsied the two male and two female 
Cuvier's beaked whales. According to the pathologists, the most likely 
primary cause of this type of beaked whale mass stranding event was 
anthropogenic acoustic activities, most probably anti-submarine MFAS 
used during the military naval exercises. However, no positive acoustic 
link was established as a direct cause of the stranding. Even though no 
causal link can be made between the stranding event and naval 
exercises, certain conditions may have existed in the exercise area 
that, in their aggregate, may have contributed to the marine mammal 
strandings (Freitas, 2004): exercises were conducted in areas of at 
least 547 fathoms (1,000 m) depth near a shoreline where there is a 
rapid change in bathymetry on the order of 547 to 3,281 fathoms (1,000 
to 6,000 m) occurring across a relatively short horizontal distance 
(Freitas, 2004); multiple ships (in this instance, five) were operating 
MFAS in the same area over extended periods of time (in this case, 20 
hours) in close proximity; and exercises took place in an area 
surrounded by landmasses, or in an embayment. Exercises involving 
multiple ships employing MFAS near land may have produced sound 
directed towards a channel or embayment that may have cut off the lines 
of egress for the affected marine mammals (Freitas, 2004).

Association Between Mass Stranding Events and Exposure to MFAS

    Several authors have noted similarities between some of these 
stranding incidents: they occurred in islands or archipelagoes with 
deep water nearby, several appeared to have been associated with 
acoustic waveguides like surface ducting, and the sound fields created 
by ships transmitting MFAS (Cox et al., 2006, D'Spain et al., 2006). 
Although Cuvier's

[[Page 7009]]

beaked whales have been the most common species involved in these 
stranding events (81 percent of the total number of stranded animals), 
other beaked whales (including Mesoplodon europeaus, M. densirostris, 
and Hyperoodon ampullatus) comprise 14 percent of the total. Other 
species (Stenella coeruleoalba, Kogia breviceps and Balaenoptera 
acutorostrata) have stranded, but in much lower numbers and less 
consistently than beaked whales.
    Based on the evidence available, however, we cannot determine 
whether (a) Cuvier's beaked whale is more prone to injury from high-
intensity sound than other species; (b) their behavioral responses to 
sound makes them more likely to strand; or (c) they are more likely to 
be exposed to MFAS than other cetaceans (for reasons that remain 
unknown). Because the association between active sonar exposures and 
marine mammals mass stranding events is not consistent--some marine 
mammals strand without being exposed to sonar and some sonar 
transmissions are not associated with marine mammal stranding events 
despite their co-occurrence--other risk factors or a grouping of risk 
factors probably contribute to these stranding events.

Behaviorally Mediated Responses to MFAS That May Lead to Stranding

    Although the confluence of Navy MFAS with the other contributory 
factors noted in the report was identified as the cause of the 2000 
Bahamas stranding event, the specific mechanisms that led to that 
stranding (or the others) are not understood, and there is uncertainty 
regarding the ordering of effects that led to the stranding. It is 
unclear whether beaked whales were directly injured by sound (e.g., 
acoustically mediated bubble growth, as addressed above) prior to 
stranding or whether a behavioral response to sound occurred that 
ultimately caused the beaked whales to be injured and strand.
    Although causal relationships between beaked whale stranding events 
and active sonar remain unknown, several authors have hypothesized that 
stranding events involving these species in the Bahamas and Canary 
Islands may have been triggered when the whales changed their dive 
behavior in a startled response to exposure to active sonar or to 
further avoid exposure (Cox et al., 2006, Rommel et al., 2006). These 
authors proposed three mechanisms by which the behavioral responses of 
beaked whales upon being exposed to active sonar might result in a 
stranding event. These include the following: gas bubble formation 
caused by excessively fast surfacing; remaining at the surface too long 
when tissues are supersaturated with nitrogen; or diving prematurely 
when extended time at the surface is necessary to eliminate excess 
nitrogen. More specifically, beaked whales that occur in deep waters 
that are in close proximity to shallow waters (for example, the 
``canyon areas'' that are cited in the Bahamas stranding event; see 
D'Spain and D'Amico, 2006), may respond to active sonar by swimming 
into shallow waters to avoid further exposures and strand if they were 
not able to swim back to deeper waters. Second, beaked whales exposed 
to active sonar might alter their dive behavior. Changes in their dive 
behavior might cause them to remain at the surface or at depth for 
extended periods of time which could lead to hypoxia directly by 
increasing their oxygen demands or indirectly by increasing their 
energy expenditures (to remain at depth) and increase their oxygen 
demands as a result. If beaked whales are at depth when they detect a 
ping from an active sonar transmission and change their dive profile, 
this could lead to the formation of significant gas bubbles, which 
could damage multiple organs or interfere with normal physiological 
function (Cox et al., 2006; Rommel et al., 2006; Zimmer and Tyack, 
2007). Baird et al. (2005) found that slow ascent rates from deep dives 
and long periods of time spent within 50 m of the surface were typical 
for both Cuvier's and Blainville's beaked whales, the two species 
involved in mass strandings related to naval sonar. These two 
behavioral mechanisms may be necessary to purge excessive dissolved 
nitrogen concentrated in their tissues during their frequent long dives 
(Baird et al., 2005). Baird et al. (2005) further suggests that 
abnormally rapid ascents or premature dives in response to high-
intensity sonar could indirectly result in physical harm to the beaked 
whales, through the mechanisms described above (gas bubble formation or 
non-elimination of excess nitrogen).
    Because many species of marine mammals make repetitive and 
prolonged dives to great depths, it has long been assumed that marine 
mammals have evolved physiological mechanisms to protect against the 
effects of rapid and repeated decompressions. Although several 
investigators have identified physiological adaptations that may 
protect marine mammals against nitrogen gas supersaturation (alveolar 
collapse and elective circulation; Kooyman et al., 1972; Ridgway and 
Howard, 1979), Ridgway and Howard (1979) reported that bottlenose 
dolphins that were trained to dive repeatedly had muscle tissues that 
were substantially supersaturated with nitrogen gas. Houser et al. 
(2001) used these data to model the accumulation of nitrogen gas within 
the muscle tissue of other marine mammal species and concluded that 
cetaceans that dive deep and have slow ascent or descent speeds would 
have tissues that are more supersaturated with nitrogen gas than other 
marine mammals. Based on these data, Cox et al. (2006) hypothesized 
that a critical dive sequence might make beaked whales more prone to 
stranding in response to acoustic exposures. The sequence began with 
(1) Very deep (to depths as deep as 2 kilometers) and long (as long as 
90 minutes) foraging dives; (2) relatively slow, controlled ascents; 
and (3) a series of ``bounce'' dives between 100 and 400 m in depth 
(also see Zimmer and Tyack, 2007). They concluded that acoustic 
exposures that disrupted any part of this dive sequence (for example, 
causing beaked whales to spend more time at surface without the bounce 
dives that are necessary to recover from the deep dive) could produce 
excessive levels of nitrogen supersaturation in their tissues, leading 
to gas bubble and emboli formation that produces pathologies similar to 
decompression sickness.
    Zimmer and Tyack (2007) modeled nitrogen tension and bubble growth 
in several tissue compartments for several hypothetical dive profiles 
and concluded that repetitive shallow dives (defined as a dive where 
depth does not exceed the depth of alveolar collapse, approximately 72 
m for Ziphius), perhaps as a consequence of an extended avoidance 
reaction to sonar sound, could pose a risk for decompression sickness 
and that this risk should increase with the duration of the response. 
Their models also suggested that unrealistically rapid ascent rates of 
ascent from normal dive behaviors are unlikely to result in 
supersaturation to the extent that bubble formation would be expected. 
Tyack et al. (2006) suggested that emboli observed in animals exposed 
to mid-frequency range sonar (Jepson et al., 2003; Fernandez et al., 
2005) could stem from a behavioral response that involves repeated 
dives shallower than the depth of lung collapse. Given that nitrogen 
gas accumulation is a passive process (i.e. nitrogen is metabolically 
inert), a bottlenose dolphin was trained to repetitively dive a profile 
predicted to elevate nitrogen saturation to the point that nitrogen 
bubble formation was

[[Page 7010]]

predicted to occur. However, inspection of the vascular system of the 
dolphin via ultrasound did not demonstrate the formation of 
asymptomatic nitrogen gas bubbles (Houser et al., 2007). Baird et al. 
(2008), in a beaked whale tagging study off Hawaii, showed that deep 
dives are equally common during day or night, but ``bounce dives'' are 
typically a daytime behavior, possibly associated with visual predator 
avoidance. This may indicate that ``bounce dives'' are associated with 
something other than behavioral regulation of dissolved nitrogen 
levels, which would be necessary day and night.
    If marine mammals respond to a Navy vessel that is transmitting 
active sonar in the same way that they might respond to a predator, 
their probability of flight responses should increase when they 
perceive that Navy vessels are approaching them directly, because a 
direct approach may convey detection and intent to capture (Burger and 
Gochfeld, 1981, 1990; Cooper, 1997, 1998). The probability of flight 
responses should also increase as received levels of active sonar 
increase (and the ship is, therefore, closer) and as ship speeds 
increase (that is, as approach speeds increase). For example, the 
probability of flight responses in Dall's sheep (Ovis dalli dalli) 
(Frid 2001a, b), ringed seals (Phoca hispida) (Born et al., 1999), 
Pacific brant (Branta bernic nigricans) and Canada geese (B. 
Canadensis) increased as a helicopter or fixed-wing aircraft approached 
groups of these animals more directly (Ward et al., 1999). Bald eagles 
(Haliaeetus leucocephalus) perched on trees alongside a river were also 
more likely to flee from a paddle raft when their perches were closer 
to the river or were closer to the ground (Steidl and Anthony, 1996).
    Despite the many theories involving bubble formation (both as a 
direct cause of injury (see Acoustically Mediated Bubble Growth 
Section) and an indirect cause of stranding (See Behaviorally Mediated 
Bubble Growth Section), Southall et al., (2007) summarizes that there 
is either scientific disagreement or a lack of information regarding 
each of the following important points: (1) Received acoustical 
exposure conditions for animals involved in stranding events; (2) 
pathological interpretation of observed lesions in stranded marine 
mammals; (3) acoustic exposure conditions required to induce such 
physical trauma directly; (4) whether noise exposure may cause 
behavioral reactions (such as atypical diving behavior) that 
secondarily cause bubble formation and tissue damage; and (5) the 
extent the post mortem artifacts introduced by decomposition before 
sampling, handling, freezing, or necropsy procedures affect 
interpretation of observed lesions.

Impulsive Sources

    Underwater explosive detonations send a shock wave and sound energy 
through the water and can release gaseous by-products, create an 
oscillating bubble, or cause a plume of water to shoot up from the 
water surface. The shock wave and accompanying noise are of most 
concern to marine animals. Depending on the intensity of the shock wave 
and size, location, and depth of the animal, an animal can be injured, 
killed, suffer non-lethal physical effects, experience hearing related 
effects with or without behavioral responses, or exhibit temporary 
behavioral responses or tolerance from hearing the blast sound. 
Generally, exposures to higher levels of impulse and pressure levels 
would result in greater impacts to an individual animal.
    Injuries resulting from a shock wave take place at boundaries 
between tissues of different densities. Different velocities are 
imparted to tissues of different densities, and this can lead to their 
physical disruption. Blast effects are greatest at the gas-liquid 
interface (Landsberg, 2000). Gas-containing organs, particularly the 
lungs and gastrointestinal tract, are especially susceptible (Goertner, 
1982; Hill, 1978; Yelverton et al., 1973). In addition, gas-containing 
organs including the nasal sacs, larynx, pharynx, trachea, and lungs 
may be damaged by compression/expansion caused by the oscillations of 
the blast gas bubble (Reidenberg and Laitman, 2003). Intestinal walls 
can bruise or rupture, with subsequent hemorrhage and escape of gut 
contents into the body cavity. Less severe gastrointestinal tract 
injuries include contusions, petechiae (small red or purple spots 
caused by bleeding in the skin), and slight hemorrhaging (Yelverton et 
al., 1973).
    Because the ears are the most sensitive to pressure, they are the 
organs most sensitive to injury (Ketten, 2000). Sound-related damage 
associated with sound energy from detonations can be theoretically 
distinct from injury from the shock wave, particularly farther from the 
explosion. If a noise is audible to an animal, it has the potential to 
damage the animal's hearing by causing decreased sensitivity (Ketten, 
1995). Sound-related trauma can be lethal or sublethal. Lethal impacts 
are those that result in immediate death or serious debilitation in or 
near an intense source and are not, technically, pure acoustic trauma 
(Ketten, 1995). Sublethal impacts include hearing loss, which is caused 
by exposures to perceptible sounds. Severe damage (from the shock wave) 
to the ears includes tympanic membrane rupture, fracture of the 
ossicles, damage to the cochlea, hemorrhage, and cerebrospinal fluid 
leakage into the middle ear. Moderate injury implies partial hearing 
loss due to tympanic membrane rupture and blood in the middle ear. 
Permanent hearing loss also can occur when the hair cells are damaged 
by one very loud event, as well as by prolonged exposure to a loud 
noise or chronic exposure to noise. The level of impact from blasts 
depends on both an animal's location and, at outer zones, on its 
sensitivity to the residual noise (Ketten, 1995).
    There have been fewer studies addressing the behavioral effects of 
explosives on marine mammals compared to MFAS/HFAS. However, though the 
nature of the sound waves emitted from an explosion are different (in 
shape and rise time) from MFAS/HFAS, we still anticipate the same sorts 
of behavioral responses to result from repeated explosive detonations 
(a smaller range of likely less severe responses (i.e., not rising to 
the level of MMPA harassment) would be expected to occur as a result of 
exposure to a single explosive detonation that was not powerful enough 
or close enough to the animal to cause TTS or injury).

Vessel Strike

    Commercial and Navy ship strikes of cetaceans can cause major 
wounds, which may lead to the death of the animal. An animal at the 
surface could be struck directly by a vessel, a surfacing animal could 
hit the bottom of a vessel, or an animal just below the surface could 
be cut by a vessel's propeller. The severity of injuries typically 
depends on the size and speed of the vessel (Knowlton and Kraus, 2001; 
Laist et al., 2001; Vanderlaan and Taggart, 2007). 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., the sperm whale). In addition, some baleen whales, 
such as the North Atlantic right whale, 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. Smaller marine mammals (e.g., bottlenose dolphin) move quickly 
through the water column and are often seen riding the bow wave of 
large ships. Marine mammal responses to vessels

[[Page 7011]]

may include avoidance and changes in dive pattern (NRC, 2003).
    An examination of all known ship strikes from all shipping sources 
(civilian and military) indicates vessel speed is a principal factor in 
whether a vessel strike results in death (Knowlton and Kraus, 2001; 
Laist et al., 2001; Jensen and Silber, 2003; Vanderlaan and Taggart, 
2007). In assessing records in which vessel speed was known, Laist et 
al. (2001) found a direct relationship between the occurrence of a 
whale strike and the speed of the vessel involved in the collision. The 
authors concluded that most deaths occurred when a vessel was traveling 
in excess of 13 knots.
    Jensen and Silber (2003) detailed 292 records of known or probable 
ship strikes of all large whale species from 1975 to 2002. Of these, 
vessel speed at the time of collision was reported for 58 cases. Of 
these cases, 39 (or 67 percent) resulted in serious injury or death (19 
of those resulted in serious injury as determined by blood in the 
water, propeller gashes or severed tailstock, and fractured skull, jaw, 
vertebrae, hemorrhaging, massive bruising or other injuries noted 
during necropsy and 20 resulted in death). Operating speeds of vessels 
that struck various species of large whales ranged from 2 to 51 knots. 
The majority (79 percent) of these strikes occurred at speeds of 13 
knots or greater. The average speed that resulted in serious injury or 
death was 18.6 knots. Pace and Silber (2005) found that the probability 
of death or serious injury increased rapidly with increasing vessel 
speed. Specifically, the predicted probability of serious injury or 
death increased from 45 to 75 percent as vessel speed increased from 10 
to 14 knots, and exceeded 90 percent at 17 knots. Higher speeds during 
collisions result in greater force of impact, but higher speeds also 
appear to increase the chance of severe injuries or death by pulling 
whales toward the vessel. Computer simulation modeling showed that 
hydrodynamic forces pulling whales toward the vessel hull increase with 
increasing speed (Clyne, 1999; Knowlton et al., 1995).
    The Jensen and Silber (2003) report notes that the database 
represents a minimum number of collisions, because the vast majority 
probably goes undetected or unreported. In contrast, Navy vessels are 
likely to detect any strike that does occur, and they are required to 
report all ship strikes involving marine mammals. Overall, the 
percentages of Navy traffic relative to overall large shipping traffic 
are very small (on the order of 2 percent).
    Over a period of 20 years from 1991 to 2010 there have been a total 
of 16 Navy vessel strikes in SOCAL, and five Navy vessel strikes in 
HRC. Two of the five HRC Navy strikes were by smaller workboats (less 
than 12 m in length), versus larger Navy ships. In terms of the 16 
consecutive 5-year periods in the last 20 years, no single 5-year 
period exceeded ten whales struck within SOCAL and HRC (periods from 
2000-2004 and 2001-2005). For Navy vessel strikes in SOCAL, there were 
six consecutive 5-year periods with six or more whales struck (1997-
2001, 1998-2002, 1999-2003, 2000-2004, 2001-2005, and 2002-2006), and 
no more than three whales struck in the last 5-year period from 2006-
2010. No whales have been struck by Navy vessels in SOCAL since 2009. 
For Navy vessel strikes in the HRC for the same time period, there was 
one 5-year period when three whales were struck (2003-2007), seven 
periods when two whales were struck, five periods when one whale was 
struck, and three periods when no whales were struck. Within the data 
set analyzed for HRC through 2010, no whales have been struck by a Navy 
vessel since 2008.

Mitigation

    In order to issue an incidental take authorization 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.'' The NDAA of 2004 amended the MMPA as 
it relates to military-readiness activities and the ITA process such 
that ``least practicable adverse impact'' shall include consideration 
of personnel safety, practicality of implementation, and impact on the 
effectiveness of the ``military readiness activity''. The training and 
testing activities described in the Navy's LOA application are 
considered military readiness activities.
    NMFS reviewed the proposed activities and the proposed mitigation 
measures as described in the Navy's LOA application to determine if 
they would result in the least practicable adverse effect on marine 
mammals, which includes a careful balancing of the likely benefit of 
any particular measure to the marine mammals with the likely effect of 
that measure on personnel safety, practicality of implementation, and 
impact on the effectiveness of the ``military-readiness activity.'' 
Included below are the mitigation measures the Navy proposed in their 
LOA application.

Proposed Mitigation Measures

    They Navy's proposed mitigation measures are modifications to the 
proposed activities that are implemented for the sole purpose of 
reducing a specific potential environmental impact on a particular 
resource. These do not include standard operating procedures, which are 
established for reasons other than environmental benefit. Most of the 
following proposed mitigation measures are currently, or were 
previously, implemented as a result of past environmental compliance 
documents. The Navy's overall approach to assessing potential 
mitigation measures is based on two principles: (1) mitigation measures 
will be effective at reducing potential impacts on the resource, and 
(2) from a military perspective, the mitigation measures are 
practicable, executable, and safety and readiness will not be impacted.

Lookouts

    The use of lookouts is a critical component of Navy procedural 
measures and implementation of mitigation zones. Navy lookouts are 
highly qualified and experienced observers of the marine environment. 
Their duties require that they report all objects sighted in the water 
to the Officer of the Deck (OOD) (e.g., trash, a periscope, marine 
mammals, sea turtles) and all disturbances (e.g., surface disturbance, 
discoloration) that may be indicative of a threat to the vessel and its 
crew. There are personnel standing watch on station at all times (day 
and night) when a ship or surfaced submarine is moving through the 
water.
    The Navy would have two types of lookouts for the purposes of 
conducting visual observations: (1) those positioned on surface ships, 
and (2) those positioned in aircraft or on boats. Lookouts positioned 
on surface ships would be dedicated solely to diligent observation of 
the air and surface of the water. They would have multiple observation 
objectives, which include but are not limited to detecting the presence 
of biological resources and recreational or fishing boats, observing 
mitigation zones, and monitoring for vessel and personnel safety 
concerns.
    Due to aircraft and boat manning and space restrictions, lookouts 
positioned in aircraft or on boats would consist of the aircraft crew, 
pilot, or boat crew. Lookouts positioned in aircraft and boats may 
necessarily be responsible for tasks in addition to observing the air 
or surface of the water (for example,

[[Page 7012]]

navigation of a helicopter or rigid hull inflatable boat). However, 
aircraft and boat lookouts would, to the maximum extent practicable and 
consistent with aircraft and boat safety and training and testing 
requirements, comply with the observation objectives described above 
for lookouts positioned on surface ships.
    The Navy proposes to use at least one lookout during the training 
and testing activities provided in Table 10. Additional details on 
lookout procedures and implementation are provided in Chapter 11 of the 
Navy's LOA application (http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications).

     Table 10--Lookout Mitigation Measures for Training and Testing
                  Activities Within the HSTT Study Area
------------------------------------------------------------------------
                              Training and testing
     Number of lookouts            activities              Benefit
------------------------------------------------------------------------
4...........................  Mine countermeasure   Lookouts can
                               and neutralization    visually detect
                               activities using      marine mammals so
                               time delay would      that potentially
                               use 4, depending on   harmful impacts
                               the explosives        from explosives use
                               being used. If        can be avoided.
                               applicable, aircrew
                               and divers would
                               report sightings of
                               marine mammals.
                                                    Lookouts dedicated
                                                     to observations can
                                                     more quickly and
                                                     effectively relay
                                                     sighting
                                                     information so that
                                                     corrective action
                                                     can be taken.
                                                     Support from
                                                     aircrew and divers,
                                                     if they have are
                                                     involved, would
                                                     increase the
                                                     probability of
                                                     sightings, reducing
                                                     the potential for
                                                     impacts.
1 to 2......................  Vessels using low-    Lookouts can
                               frequency active      visually detect
                               sonar or hull-        marine mammals so
                               mounted mid-          that potentially
                               frequency active      harmful impacts
                               sonar associated      from Navy sonar and
                               with ASW activities   explosives use can
                               would have either     be avoided.
                               one or two            Dedicated lookouts
                               lookouts, depending   can more quickly
                               on the size and       and effectively
                               status/location of    relay sighting
                               the vessel.           information so that
                                                     corrective action
                                                     can be taken.
                                                     Support from
                                                     aircrew and divers,
                                                     if they are
                                                     involved, would
                                                     increase the
                                                     probability of
                                                     sightings, reducing
                                                     the potential for
                                                     impacts.
                              Mine countermeasure
                               and neutralization
                               activities with
                               positive control
                               would use one or
                               two lookouts
                               (depending on net
                               explosive weight),
                               with at least one
                               on each support
                               vessel. If
                               applicable, aircrew
                               and divers would
                               also report the
                               presence of marine
                               mammals.
                              Mine neutralization
                               activities
                               involving diver
                               placed charges of
                               up to 100 lb (45
                               kg) net explosive
                               weight detonation
                               would use two
                               lookouts.
                              Sinking exercises
                               would use two
                               lookouts (one in an
                               aircraft and one on
                               a vessel).
                              At sea explosives
                               testing would have
                               at least one
                               lookout.
1...........................  Surface ships and     Lookouts can
                               aircraft conducting   visually detect
                               ASW, ASUW, or MIW     marine mammals so
                               activities using      that potentially
                               high-frequency        harmful impacts
                               active sonar; non-    from Navy sonar;
                               hull mounted mid-     explosives;
                               frequency active      sonobuoys; gunnery
                               sonar; helicopter     rounds; missiles;
                               dipping mid-          explosive
                               frequency active      torpedoes; pile
                               sonar; anti-swimmer   driving; towed
                               grenades; IEER        systems; surface
                               sonobuoys; line       vessel propulsion;
                               charge testing;       and non-explosive
                               surface gunnery       munitions can be
                               activities; surface   avoided.
                               missile activities;
                               bombing activities;
                               explosive torpedo
                               testing; elevated
                               causeway system
                               pile driving; towed
                               in-water devices;
                               full power
                               propulsion testing
                               of surface vessels;
                               and activities
                               using non-explosive
                               practice munitions,
                               would have one
                               lookout.
------------------------------------------------------------------------

    Personnel standing watch on the bridge, Commanding Officers, 
Executive Officers, maritime patrol aircraft aircrews, anti-submarine 
warfare helicopter crews, civilian equivalents, and lookouts would 
complete the NMFS-approved Marine Species Awareness Training (MSAT) 
prior to standing watch or serving as a lookout. Additional details on 
the Navy's MSAT program are provided in Chapter 5 of the HSTT DEIS/
OEIS.

Mitigation Zones

    The Navy proposes to use mitigation zones to reduce the potential 
impacts to marine mammals from training and testing activities. 
Mitigation zones are measured as the radius from a source and represent 
a distance that the Navy would monitor. Mitigation zones are applied to 
acoustic stressors (i.e., non-impulsive and impulsive sound) and 
physical strike and disturbance (e.g., vessel movement and bombing 
exercises). In each instance, visual detections of marine mammals would 
be communicated immediately to a watch station for information 
dissemination and appropriate action. Acoustic detections would be 
communicated to lookouts posted in aircraft and on surface vessels.
    Most of the current mitigation zones for activities that involve 
the use of impulsive and non-impulsive sources were originally designed 
to reduce the potential for onset of TTS. The Navy updated their 
acoustic propagation modeling to incorporate new hearing threshold 
metrics (i.e., upper and lower frequency limits), new marine mammal 
density data, and factors such as an animal's likely presence at 
various depths. An explanation of the acoustic propagation modeling 
process can be found in the Marine Species Modeling Team Technical 
Report (U.S. Department of the Navy 2012a).
    As a result of updates to the acoustic propagation modeling, some 
of the ranges to effects are larger than previous model outputs. Due to 
the ineffectiveness of mitigating such large areas, the Navy is unable 
to mitigate for onset of TTS during every activity. However, some 
ranges to effects are smaller than previous models estimated, and the 
mitigation zones were adjusted accordingly to provide consistency 
across the measures. The Navy developed each proposed mitigation zone 
to avoid or reduce the potential for

[[Page 7013]]

onset of the lowest level of injury, PTS, out to the predicted maximum 
range. Mitigating to the predicted maximum range to PTS also mitigates 
to the predicted maximum range to onset mortality (1 percent 
mortality), onset slight lung injury, and onset slight gastrointestinal 
tract injury, since the maximum range to effects for these criteria are 
shorter than for PTS. Furthermore, in most cases, the predicted maximum 
range to PTS also covers the predicted average range to TTS. Tables 11 
and 12 summarize the predicted average range to TTS, average range to 
PTS, maximum range to PTS, and recommended mitigation zone for each 
activity category, based on the Navy's acoustic propagation modeling 
results. It is important for the Navy to have standardized mitigation 
zones wherever training and testing may be conducted. The information 
in Tables 11 and 12 was developed in consideration of both Atlantic and 
Pacific Ocean conditions, marine mammal species, environmental factors, 
effectiveness, and operational assessments. Therefore, the ranges to 
effects in Tables 11 and 12 provide effective values that ensure 
appropriate mitigation ranges for both Atlantic Fleet and Pacific Fleet 
activities, and may not align with range to effects values found in 
other tables of the Navy's LOA application.
    The Navy's proposed mitigation zones are based on the longest range 
for all the marine mammal and sea turtle functional hearing groups. 
Most mitigation zones were driven by the high-frequency cetaceans or 
sea turtles functional hearing group. Therefore, the mitigation zones 
are more conservative for the remaining functional hearing groups (low-
frequency and mid-frequency cetaceans, and pinnipeds), and likely cover 
a larger portion of the potential range to onset of TTS. Additional 
information on the estimated range to effects for each acoustic 
stressor is detailed in Chapter 11 of the Navy's LOA application 
(http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications).

                                        Table 11--Predicted Ranges to TTS, PTS, and Recommended Mitigation Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                       Bin (representative      Predicted average      Predicted average      Predicted maximum         Recommended
         Activity category                  source)*              range to TTS            range to PTS           range to PTS         mitigation zone
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Non-Impulsive Sound
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
Low-Frequency and Hull-Mounted Mid-  MF1 (SQS-53 ASW hull-   4,251 yd. (3,887 m)...  281 yd. (257 m)......  <292 yd. (<267 m)....  6 dB power down at
 Frequency Active Sonar \1\.          mounted sonar).                                                                               1,000 yd. (914 m); 4
                                                                                                                                    dB power down at 500
                                                                                                                                    yd. (457 m); and
                                                                                                                                    shutdown at 200 yd.
                                                                                                                                    (183 m).
High-Frequency and Non-Hull Mounted  MF4 (AQS-22 ASW         226 yd. (207 m).......  <55 yd. (<50 m)......  <55 yd. (<50 m)......  200 yd. (183 m).
 Mid-Frequency Active Sonar.          dipping sonar).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Explosive and Impulsive Sound
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
Improved Extended Echo Ranging       E4 (Explosive           434 yd. (397 m).......  156 yd. (143 m)......  563 yd. (515 m)......  600 yd. (549 m).
 Sonobuoys.                           sonobuoy).
Explosive Sonobuoys using 0.6-2.5    E3 (Explosive           290 yd. (265 m).......  113 yd. (103 m)......  309 yd. (283 m)......  350 yd. (320 m).
 lb. NEW.                             sonobuoy).
Anti-Swimmer Grenades..............  E2 (Up to 0.5 lb. NEW)  190 yd. (174 m).......  83 yd. (76 m)........  182 yd. (167 m)......  200 yd. (183 m).
                                    --------------------------------------------------------------------------------------------------------------------
Mine Countermeasure and                                                         NEW dependent (see Table 12).
 Neutralization Activities Using
 Positive Control Firing Devices.
                                    --------------------------------------------------------------------------------------------------------------------
Mine Neutralization Diver-Placed     E6 (Up to 20 lb. NEW).  647 yd. (592 m).......  232 yd. (212 m)......  469 yd. (429 m)......  1,000 yd. (915 m).
 Mines Using Time-Delay Firing
 Devices.
Ordnance Testing (Line Charge        E4 (Numerous 5 lb.      434 yd. (397 m).......  156 yd. (143 m)......  563 yd. (515 m)......  900 yd. (823 m).**
 Testing).                            charges).
Gunnery Exercises--Small- and        E2 (40 mm projectile).  190 yd. (174 m).......  83 yd. (76 m)........  182 yd. (167 m)......  200 yd. (183 m).
 Medium-Caliber (Surface Target).
Gunnery Exercises--Large-Caliber     E5 (5 in. projectiles   453 yd. (414 m).......  186 yd. (170 m)......  526 yd. (481 m)......  600 yd. (549 m).
 (Surface Target).                    at the surface***).
Missile Exercises up to 250 lb. NEW  E9 (Maverick missile).  949 yd. (868 m).......  398 yd. (364 m)......  699 yd. (639 m)......  900 yd. (823 m).
 (Surface Target).
Missile Exercises up to 500 lb. NEW  E10 (Harpoon missile).  1,832 yd. (1,675 m)...  731 yd. (668 m)......  1,883 yd. (1,721 m)..  2,000 yd. (1.8 km).
 (Surface Target).
Bombing Exercises..................  E12 (MK-84 2,000 lb.    2,513 yd. (2.3 km)....  991 yd. (906 m)......  2,474 yd. (2.3 km)...  2,500 yd. (2.3 km).**
                                      bomb).
Torpedo (Explosive) Testing........  E11 (MK-48 torpedo)...  1,632 yd. (1.5 km)....  697 yd. (637 m)......  2,021 yd. (1.8 km)...  2,100 yd. (1.9 km).
Sinking Exercises..................  E12 (Various sources    2,513 yd. (2.3 km)....  991 yd. (906 m)......  2,474 yd. (2.3 km)...  2.5 nm.
                                      up to the MK-84 2,000
                                      lb. bomb).

[[Page 7014]]

 
At-Sea Explosive Testing...........  E5 (Various sources     525 yd. (480 m).......  204 yd. (187 m)......  649 yd. (593 m)......  1,600 yd. (1.4 km).**
                                      less than 10 lb. NEW
                                      at various depths***).
Elevated Causeway System--Pile       24 in. steel impact     1,094 yd. (1,000 m)...  51 yd. (46 m)........  51 yd. (46 m)........  60 yd. (55 m).
 Driving.                             hammer.
--------------------------------------------------------------------------------------------------------------------------------------------------------
ASW: anti-submarine warfare; JAX: Jacksonville; NEW: net explosive weight; PTS: permanent threshold shift; TTS: temporary threshold shift.
\1\ The mitigation zone would be 200 yd for bin LF4 testing sources.
* This table does not provide an inclusive list of source bins; bins presented here represent the source bin with the largest range to effects within
  the given activity category.
** Recommended mitigation zones are larger than the modeled injury zones to account for multiple types of sources or charges being used.
*** The representative source bin E5 has different range to effects depending on the depth of activity occurrence (at the surface or at various depths).


                  Table 12--Predicted Ranges to Effects and Mitigation Zone Radius for Mine Countermeasure and Neutralization Activities Using Positive Control Firing Devices
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                     General mine countermeasure and neutralization activities using positive      Mine countermeasure and neutralization activities using diver placed charges
                                                             control firing devices *                                                        under positive control **
Charge size net explosive weight ---------------------------------------------------------------------------------------------------------------------------------------------------------------
             (bins)                Predicted average   Predicted average   Predicted maximum      Recommended      Predicted average   Predicted average   Predicted maximum      Recommended
                                     range to TTS        range to PTS        range to PTS       mitigation zone      range to TTS        range to PTS        range to PTS       mitigation zone
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
2.6-5 lb. (1.2-2.3 kg) (E4).....  434 yd. (474 m)...  197 yd. (180 m)...  563 yd. (515 m)...  600 yd. (549 m)...  545 yd. (498 m)...  169 yd. (155 m)...  301 yd. (275 m)...  350 yd. (320 m).
6-10 lb. (2.7-4.5 kg) (E5)......  525 yd. (480 m)...  204 yd. (187 m)...  649 yd. (593 m)...  800 yd. (732 m)...  587 yd. (537 m)...  203 yd. (185 m)...  464 yd. (424 m)...  500 yd. (457 m).
11-20 lb. (5-9.1 kg) (E6).......  766 yd. (700 m)...  288 yd. (263 m)...  648 yd. (593 m)...  800 yd. (732 m)...  647 yd. (592 m)...  232 yd. (212 m)...  469 yd. (429 m)...  500 yd. (457 m).
21-60 lb. (9.5-27.2 kg) (E7) ***  1,670 yd. (1,527    581 yd. (531 m)...  964 yd. (882 m)...  1,200 yd. (1.1 km)  1,532 yd. (1,401    473 yd. (432 m)...  789 yd. (721 m)...  800 yd. (732 m).
                                   m).                                                                             m).
61-100 lb. (27.7-45.4 kg) (E8)    878 yd. (802 m)...  383 yd. (351 m)...  996 yd. (911 m)...  1,600 yd. (1.4 m).  969 yd. (886 m)...  438 yd. (400 m)...  850 yd. (777 m)...  850 yd. (777 m).
 ****.
250-500 lb. (113.4-226.8 kg)      1,832 yd. (1,675    731 yd. (668 m)...  1,883 yd. (1,721    2,000 yd. (1.8 km)  ..................  ..................  ..................  Not Applicable.
 (E10).                            m).                                     m).
501-650 lb. (227.3-294.8) (E11).  1,632 yd. (1,492    697 yd. (637 m)...  2,021 yd. (1,848    2,100 yd. (1.9 km)  ..................  ..................  ..................  Not Applicable.
                                   m).                                     m).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
PTS: permanent threshold shift; TTS: temporary threshold shift
* These mitigation zones are applicable to all mine countermeasure and neutralization activities conducted in all locations that Tables 2.8-1 through 2.8-5 specifies.
** These mitigation zones are only applicable to mine countermeasure and neutralization activities involving the use of diver placed charges. These activities are conducted in shallow water
  and the mitigation zones are based only on the functional hearing groups with species that occur in these areas (mid-frequency cetaceans and sea turtles).
*** The E7 bin was only modeled in shallow-water locations so there is no difference for the diver placed charges category.
**** The E8 bin was only modeled for surface explosions, so some of the ranges are shorter than for sources modeled in the E7 bin which occur at depth.

    When mine neutralization activities using diver placed charges (up 
to a 20 lb. NEW) are conducted with a time-delay firing device, the 
detonation is fused with a specified time-delay by the personnel 
conducting the activity and is not authorized until the area is clear 
at the time the fuse is initiated. During these activities, the 
detonation cannot be terminated once the fuse is initiated due to human 
safety concerns. The Navy is proposing to modify the number of lookouts 
currently used for mine neutralization activities using diver-placed 
time-delay firing devices. As a reference, the current mitigation 
involves the use of six lookouts and three small rigid hull inflatable 
boats (two lookouts positioned in each of the three boats) for 
mitigation zones equal to or larger than 1,400 yd. (1,280 m), or four 
lookouts and two boats for mitigation zones smaller than 1,400 yd. 
(1,280 m), which was incorporated into the current Silver Strand 
Training Complex IHA to minimize the possibility of take by serious 
injury or mortality (which is not authorized under an IHA). The Navy 
has determined that using six lookouts and three boats in the long term 
is impracticable to implement from an operational standpoint due to the 
impact that it is causing on resource requirements (i.e., limited 
personnel resources and boat availability). During activities using up 
to a 20 lb. NEW (bin E6) detonation, the Navy is proposing to have four 
lookouts and two small rigid hull inflatable boats (two lookouts 
positioned in each of the two boats) monitoring a 1,000-yd (915-m) 
mitigation zone. In addition, when aircraft are used, the pilot or 
member of the aircrew will serve as an additional lookout.
    NMFS believes that the Navy's proposed modification to this 
mitigation measure will still reduce the potential for injury or 
mortality for a few reasons: (1) The Navy's acoustic propagation 
modeling results show that the predicted ranges to TTS and PTS for mine 
neutralization diver-placed mines using time-delay firing devices do 
not exceed 647 yd (592 m), which is well within the proposed 1,000-yd 
(915-m) mitigation zone; (2) the number of lookouts for a 1,000-yd 
(915-m) mitigation zone would not change; (3)

[[Page 7015]]

the maximum net explosive weight would decrease from 29 lb (currently) 
to 20 lb (proposed); (4) the Navy would continue to monitor the 
mitigation zone for 30 minutes before, during, and 30 after the 
activity to ensure that the area is clear of marine mammals; and (5) 
time-delay firing device activities are only conducted during daylight 
hours.

Vessels and In-Water Devices

    Vessel Movement--Ships would avoid approaching marine mammals head 
on and would maneuver to maintain a mitigation zone of 457 m around 
observed whales, and 183 m around all other marine mammals (except bow 
riding dolphins), providing it is safe to do so.
    Towed In-water Devices--The Navy would ensure towed in-water 
devices avoid coming within a mitigation zone of 229 m around any 
observed marine mammal, providing it is safe to do so.

Non-Explosive Practice Munitions

    Gunnery Exercises (small, medium, and large caliber using a surface 
target)--Mitigation would include visual observation immediately before 
and during the exercise within a mitigation zone of 183 m around the 
intended impact location. The exercise would not commence if 
concentrations of floating vegetation (Sargassum or kelp patties) are 
observed in the mitigation zone. Firing would cease if a marine mammal 
is visually detected within the mitigation zone. Firing would 
recommence if any one of the following conditions are met: (1) The 
animal is observed exiting the mitigation zone, (2) the animal is 
thought to have exited the mitigation zone based on its course and 
speed, (3) the mitigation zone has been clear from any additional 
sightings for a period of 30 minutes, or (4) the intended target 
location has been repositioned more than 366 m away from the location 
of the last sighting.
    Bombing Exercises--Mitigation would include visual observation from 
the aircraft immediately before the exercise and during target approach 
within a mitigation zone of 914 m around the intended impact location. 
The exercise would not commence if concentrations of floating 
vegetation (Sargassum or kelp patties) are observed in the mitigation 
zone. Bombing would cease if a marine mammal is visually detected 
within the mitigation zone. Bombing would recommence if any one of the 
following conditions are met: (1) The animal is observed exiting the 
mitigation zone, (2) the animal is thought to have exited the 
mitigation zone based on its course and speed, or (3) the mitigation 
zone has been clear from any additional sightings for a period of 30 
minutes.

Other Mitigation

    The Navy Marine Mammal Program utilizes the following standard 
operating procedures to help to limit the low risk of disease 
transmission from Navy marine mammals to indigenous marine mammals, 
including the Hawaiian monk seals, while training in the HRC:
     Waste from Navy sea lions would be collected and disposed 
of in an approved sewer system;
     During operations, all onsite personnel would be made 
aware of the potential for disease transfer, and asked to report any 
sightings of monk seals immediately to other training participants;
     Sea lion handlers would visually scan for indigenous 
marine animals, especially monk seals, for at least 5 minutes before a 
Navy sea lion enters the water and would continue monitoring while the 
sea lion is in the water. If a monk seal is seen approaching or within 
100 m of the Navy sea lion, the handler would hold the Navy sea lion in 
the boat or recall the Navy sea lion immediately if it has already been 
released; and
     The Navy would obtain an import permit from the State of 
Hawaii Department of Agriculture and would adhere to the conditions of 
that permit.

Humpback Whale Cautionary Area

    The Navy is proposing to continue their designation of a humpback 
whale cautionary area in Hawaiian waters. Humpback whales migrate to 
the Hawaiian Islands each winter to rear their calves and mate. Data 
indicate that, historically, humpback whales have concentrated in high 
densities in certain areas around the Hawaiian Islands. NMFS has 
reviewed the Navy's data on MFAS training in these dense humpback whale 
areas since June 2006 and found it to be rare and infrequent. While 
past data is no guarantee of future activity, it documents a history of 
low level MFAS activity in dense humpback areas. In order to be 
successful at operational missions and against the threat of quiet, 
diesel-electric submarines, the Navy has, for more than 40 years, 
routinely conducted Anti-Submarine Warfare (ASW) training in the waters 
off the Hawaiian Islands, including the Humpback Whale National Marine 
Sanctuary. During this period, no reported cases of harmful effects to 
humpback whales attributed to MFAS use have occurred. Coincident with 
this use of MFAS, abundance estimates reflect an annual increase in the 
humpback whale stock (Mobley 2001a, 2004). A recent long-term study of 
humpback whales in Hawaiian waters shows long-term fidelity to the 
Hawaiian winter grounds, with many showing sighting spans ranging from 
10 to 32 years (Herman et al., 2011).
    NMFS and the Navy have explored ways of effecting the least 
practicable impact (which includes a consideration of practicality of 
implementation and impacts to training fidelity) to humpback whales 
from exposure to MFAS. Proficiency in ASW requires that Sailors gain 
and maintain expert skills and experience in operating MFAS in myriad 
marine environments. The Hawaiian Islands, including areas in which 
humpback whales concentrate, contain unique bathymetric features the 
Navy needs to ensure sailors gain critical skills and unique experience 
by training in coastal waters. Sound propagates differently in shallow 
water and no two shallow water areas are the same. So as not to 
negatively affect military readiness, the Navy contends that it is 
necessary to maintain the possibility of using all shallow water 
training areas. Crew members will be working in similar areas during 
real world events and these are the types of environments where enemy 
submarines may be operating.
    The Navy recognizes the significance of the Hawaiian Islands for 
humpback whales. The Navy has designated a humpback whale cautionary 
area, which consists of a 5-km (3.1-mi) buffer zone having one of the 
highest concentrations of humpback whales during winter months. Similar 
to the previous HRC rulemaking, conducting exercises in the humpback 
whale cautionary area would continue to require a much higher level of 
clearance than typically required for MFAS activities. Should national 
security needs require MFAS training and testing in the humpback whale 
cautionary area between December 15 and April 15, it shall be 
personally authorized by the Commander, U.S. Pacific Fleet (CPF). The 
CPF shall base such authorization on the unique characteristics of the 
area from a military readiness perspective, taking into account the 
importance of the area for humpback whales and the need to minimize 
adverse impacts on humpback whales from MFAS whenever practicable. 
Approval at this level for this type of activity is extraordinary. CPF 
is a four-star Admiral and the highest ranking officer in the U.S. 
Pacific Fleet. This case-by-case authorization cannot be delegated and 
represents the Navy's commitment to fully consider and balance mission 
requirements with environmental

[[Page 7016]]

stewardship. Further, CPF would provide specific direction on required 
mitigation prior to operational units transiting to and training in the 
humpback whale cautionary area. This process would ensure the decisions 
to train in this area are made at the highest level in the Pacific 
Fleet, heighten awareness of humpback whale activities in the 
cautionary area, and serve to reemphasize that mitigation measures are 
to be scrupulously followed. The Navy would provide NMFS with advance 
notification of any MFAS training and testing activities in the 
humpback whale cautionary area.
    Data from several sources, which are summarized and cited on NOAA's 
Cetacean and Sound Mapping Web site (cetsound.noaa.gov) indicate that 
there are several resident populations of odontocetes off the western 
side of the Big Island of Hawaii (e.g., beaked whales, melon-headed 
whales, dwarf sperm whales, pilot whales). Generally, we highlight the 
presence of resident populations in the interest of helping to support 
decisions that ensure that these small populations, limited to a small 
area of preferred habitat, are not exposed to concentrations of 
activities within their ranges that have the potential to impact a 
large portion of the stock/species over longer amounts of time that 
could have detrimental consequences to the stock/species. However, NMFS 
has reviewed the Navy's exercise reports and considered/discussed their 
historical level of activity in the area where these resident 
populations are concentrated, which is very low, and concluded that 
time/area restrictions would not afford much reduction of impacts in 
this location and are not necessary at this point. If future monitoring 
and exercise reports suggest that increased operations overlap with 
these resident populations, NMFS would revisit the consideration of 
time/area limitations around these populations.

Cetacean and Sound Mapping

    NMFS Office of Protected Resources standardly considers available 
information about marine mammal habitat use to inform discussions with 
applicants regarding potential spatio-temporal limitations of their 
activities that might help effect the least practicable adverse impact 
(e.g., Humpback Whale Cautionary Area). Through the Cetacean and Sound 
Mapping effort (www.cetsound.noaa.gov), NOAA's Cetacean Density and 
Distribution Mapping Working Group (CetMap) is currently involved in a 
process to compile available literature and solicit expert review to 
identify areas and times where species are known to concentrate for 
specific behaviors (e.g., feeding, breeding/calving, or migration) or 
be range-limited (e.g., small resident populations). These areas, 
called Biologically Important Areas (BIAs), are useful tools for 
planning and impact assessments and are being provided to the public 
via the CetSound Web site, along with a summary of the supporting 
information. While these BIAs are useful tools for analysts, any 
decisions regarding protective measures based on these areas must go 
through the normal MMPA evaluation process (or any other statutory 
process that the BIAs are used to inform)--the designation of a BIA 
does not pre-suppose any specific management decision associated with 
those areas. Additionally, the BIA process is iterative and the areas 
will be updated as new information becomes available. Currently, NMFS 
has published BIAs for the Arctic Slope and some in Hawaii (which were 
considered in the Mitigation Section for HSTT). The BIAs in other 
regions, such as the Atlantic and West Coast of the continental U.S. 
are still in development. We have indicated to the Navy that once these 
BIAs are complete and put on the Web site, we may need to discuss 
whether (in the context of the nature and scope of any Navy activities 
planned in and around the BIAs, what impacts might be anticipated, and 
practicability) additional protective measures might be appropriate.

Stranding Response Plan

    NMFS and the Navy developed a Stranding Response Plan for the HRC 
and SOCAL Range Complex in 2009 as part of the incidental take 
authorization process. The Stranding Response Plans are specifically 
intended to outline the applicable requirements the authorizations are 
conditioned upon in the event that a marine mammal stranding is 
reported in the HRC or SOCAL Range Complex during a major training 
exercise. NMFS considers all plausible causes within the course of a 
stranding investigation and these plans in no way presume that any 
strandings in a Navy range complex are related to, or caused by, Navy 
training and testing activities, absent a determination made during 
investigation. The plans are designed to address mitigation, 
monitoring, and compliance. The Navy is currently working with NMFS to 
refine these plans for the new HSTT Study Area (to include regionally 
specific plans that include more logistical detail). The current 
Stranding Response Plans for the HRC and SOCAL Range Complex are 
available for review here: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.

Mitigation Conclusions

    NMFS has carefully evaluated the Navy's proposed mitigation 
measures and considered a broad range of other measures in the context 
of ensuring that NMFS prescribes the means of effecting the least 
practicable adverse impact on the affected marine mammal species and 
stocks and their habitat. Our evaluation of potential measures included 
consideration of the following factors in relation to one another: the 
manner in which, and the degree to which, the successful implementation 
of the measure is expected to minimize adverse impacts to marine 
mammals; the proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned; and the practicability of the 
measure for applicant implementation, including consideration of 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.
    In some cases, additional mitigation measures are required beyond 
those that the applicant proposes. Any mitigation measure(s) prescribed 
by NMFS should be able to accomplish, have a reasonable likelihood of 
accomplishing (based on current science), or contribute to the 
accomplishment of one or more of the general goals listed below:
    a. Avoidance or minimization of injury or death of marine mammals 
wherever possible (goals b, c, and d may contribute to this goal).
    b. A reduction in the numbers of marine mammals (total number or 
number at biologically important time or location) exposed to received 
levels of MFAS/HFAS, underwater detonations, or other activities 
expected to result in the take of marine mammals (this goal may 
contribute to a, above, or to reducing harassment takes only).
    c. A reduction in the number of times (total number or number at 
biologically important time or location) individuals would be exposed 
to received levels of MFAS/HFAS, underwater detonations, or other 
activities expected to result in the take of marine mammals (this goal 
may contribute to a, above, or to reducing harassment takes only).
    d. A reduction in the intensity of exposures (either total number 
or number at biologically important time or location) to received 
levels of MFAS/HFAS, underwater detonations, or other activities 
expected to result in the take of marine mammals (this goal may 
contribute to a, above, or to reducing the severity of harassment takes 
only).

[[Page 7017]]

    e. Avoidance or minimization of adverse effects to marine mammal 
habitat, paying special attention to the food base, activities that 
block or limit passage to or from biologically important areas, 
permanent destruction of habitat, or temporary destruction/disturbance 
of habitat during a biologically important time.
    f. For monitoring directly related to mitigation--an increase in 
the probability of detecting marine mammals, thus allowing for more 
effective implementation of the mitigation (shut-down zone, etc.).
    Based on our evaluation of the Navy's proposed measures, as well as 
other measures considered by NMFS or recommended by the public, NMFS 
has determined preliminarily that the Navy's proposed mitigation 
measures (especially when the adaptive management component is taken 
into consideration (see Adaptive Management, below)) are adequate 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, while 
also considering personnel safety, practicality of implementation, and 
impact on the effectiveness of the military readiness activity. Further 
detail is included below.
    The proposed rule comment period will afford the public an 
opportunity to submit recommendations, views, and/or concerns regarding 
this action and the proposed mitigation measures. While NMFS has 
determined preliminarily that the Navy's proposed mitigation measures 
would affect the least practicable adverse impact on the affected 
species or stocks and their habitat, NMFS will consider all public 
comments to help inform our final decision. Consequently, the proposed 
mitigation measures may be refined, modified, removed, or added to 
prior to the issuance of the final rule based on public comments 
received, and where appropriate, further analysis of any additional 
mitigation measures.

Monitoring

    Section 101(a)(5)(A) of the MMPA states that in order to issue an 
ITA 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 LOAs 
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.
    Monitoring measures prescribed by NMFS should accomplish one or 
more of the following general goals:
     An increase in the probability of detecting marine 
mammals, both within the safety zone (thus allowing for more effective 
implementation of the mitigation) and in general to generate more data 
to contribute to the analyses mentioned below
     An increase in our understanding of how many marine 
mammals are likely to be exposed to levels of MFAS/HFAS (or explosives 
or other stimuli) that we associate with specific adverse effects, such 
as behavioral harassment, TTS, or PTS.
     An increase in our understanding of how marine mammals 
respond to MFAS/HFAS (at specific received levels), explosives, or 
other stimuli expected to result in take and how anticipated adverse 
effects on individuals (in different ways and to varying degrees) may 
impact the population, species, or stock (specifically through effects 
on annual rates of recruitment or survival) through any of the 
following methods:
    [cir] Behavioral observations in the presence of MFAS/HFAS compared 
to observations in the absence of sonar (need to be able to accurately 
predict received level and report bathymetric conditions, distance from 
source, and other pertinent information)
    [cir] Physiological measurements in the presence of MFAS/HFAS 
compared to observations in the absence of tactical sonar (need to be 
able to accurately predict received level and report bathymetric 
conditions, distance from source, and other pertinent information)
    [cir] Pre-planned and thorough investigation of stranding events 
that occur coincident to naval activities
    [cir] Distribution and/or abundance comparisons in times or areas 
with concentrated MFAS/HFAS versus times or areas without MFAS/HFAS
     An increased knowledge of the affected species
     An increase in our understanding of the effectiveness of 
certain mitigation and monitoring measures.

Overview of Navy Monitoring

    The current Navy Fleet monitoring program is composed of a 
collection of ``range-specific'' monitoring plans, each developed 
individually as part of the MMPA/ESA authorization processes. These 
individual plans establish specific monitoring requirements for each 
range complex based on a set of effort-based metrics (e.g., 20 days of 
aerial survey). Concurrent with implementation of the initial range-
specific monitoring plans, the Navy and NMFS began development of the 
Integrated Comprehensive Monitoring Program (ICMP). The ICMP has been 
developed in direct response to Navy permitting requirements 
established in various MMPA final rules, ESA consultations, Biological 
Opinions, and applicable regulations. The ICMP is intended to 
coordinate 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 a 
flexible, scalable, and adaptable through the adaptive management and 
strategic planning processes to periodically assess progress and 
reevaluate objectives. Although the ICMP does not specify actual 
monitoring field work or projects, it does establish top-level goals 
that have been developed in coordination with NMFS. As the ICMP is 
implemented, detailed and specific studies will be developed which 
support the Navy's 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 
accomplish one or more of the following top-level goals:
     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);
     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., tonal and impulsive sound), 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) associated 
with specific adverse effects, 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);
     An increase in our understanding of how individual marine 
mammals or ESA-listed marine species respond

[[Page 7018]]

(behaviorally or physiologically) to the specific stressors associated 
with the action (in specific contexts, where possible, e.g., at what 
distance or received level);
     An increase in 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);
     An increase in our understanding of the effectiveness of 
mitigation and monitoring measures;
     A better understanding and record of the manner in which 
the authorized entity complies with the ITA and Incidental Take 
Statement;
     An increase in the probability of detecting marine mammals 
(through improved technology or methods), both specifically within the 
safety zone (thus allowing for more effective implementation of the 
mitigation) and in general, to better achieve the above goals; and
     A reduction in the adverse impact of activities to the 
least practicable level, as defined in the MMPA.
    While the ICMP only directly applies to monitoring activities under 
applicable MMPA and ESA authorizations, it also serves to facilitate 
coordination among the Navy's marine species monitoring program and the 
basic and applied research programs discussed in the Ongoing Navy-
funded Research section of this document.
    An October 2010 Navy monitoring meeting initiated a process to 
critically evaluate current Navy monitoring plans and begin development 
of revisions to existing range-specific monitoring plans and associated 
updates to the ICMP. Discussions at that meeting and through the Navy/
NMFS adaptive management process established a way ahead for continued 
refinement of the Navy's monitoring program. This process included 
establishing a Scientific Advisory Group (SAG) composed of technical 
experts to provide objective scientific guidance for Navy 
consideration. The Navy established the SAG in early 2011 with the 
initial task of evaluating current Navy monitoring approaches under the 
ICMP and existing LOAs and developing objective scientific 
recommendations that would serve as the basis for a Strategic Planning 
Process for Navy monitoring to be incorporated as a major component of 
the ICMP. The SAG convened in March 2011, composed of leading academic 
and civilian scientists with significant expertise in marine species 
monitoring, acoustics, ecology, and modeling. The SAG's final report 
laid out both over-arching and range-specific recommendations for the 
Navy's Marine Species Monitoring program and is available through the 
Navy's Marine Species Monitoring web portal: http://www.navymarinespeciesmonitoring.us.
    Adaptive management discussions between the Navy and NMFS 
established a way ahead for continued refinement of the Navy's 
monitoring program. Consensus was that the ICMP and associated 
implementation components would continue the evolution of Navy marine 
species monitoring towards a single integrated program, incorporate SAG 
recommendations when appropriate and logistically feasible, and 
establish a more collaborative framework for evaluating, selecting, and 
implementing future monitoring across all the Navy range complexes 
through the adaptive management and strategic planning process.

Past and Current Monitoring in the HSTT Study Area

    NMFS has received multiple years' worth of annual exercise and 
monitoring reports addressing active sonar use and explosive 
detonations within the HRC, SOCAL Range Complex, and SSTC. The data and 
information contained in these reports have been considered in 
developing mitigation and monitoring measures for the proposed 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.htm#applications and http://www.navymarinespeciesmonitoring.us. NMFS has reviewed these reports and 
summarized the results, as related to marine mammal monitoring, below.
    1. The Navy has shown significant initiative in developing its 
marine species monitoring program and made considerable progress toward 
reaching goals and objectives of the ICMP.
    2. Observation data from watchstanders aboard navy vessels is 
generally useful to indicate the presence or absence of marine mammals 
within the mitigation zones (and sometimes beyond) and to document the 
implementation of mitigation measures, but does not provide useful 
species-specific information or behavioral data.
    3. Data gathered by experienced marine mammal observers can provide 
very valuable information at a level of detail not possible with 
watchstanders.
    4. Though it is by no means conclusive, it is worth noting that no 
instances of obvious behavioral disturbance have been observed by Navy 
watchstanders or experienced marine mammal observers conducting visual 
monitoring.
    5. Visual surveys generally provide suitable data for addressing 
questions of distribution and abundance of marine mammals, but are much 
less effective at providing information on movements and behavior, with 
a few notable exceptions where sightings are most frequent. For 
example, Navy-funded focal follows of marine mammals during aerial 
visual surveys in SOCAL have provided unique new science on regional 
at-sea marine mammal behavior including group size, travel direction, 
spatial occurrence within SOCAL, maximum inter-animal dispersal, and 
behavioral state.
    6. Passive acoustics and animal tagging have significant potential 
for applications addressing animal movements and behavioral response to 
Navy training activities, but require a longer time horizon and heavy 
investment in analysis to produce relevant results.
    7. NMFS and the Navy should more carefully consider what and how 
information should be gathered by watchstanders during training 
exercises and monitoring events, as some reports contain different 
information, making cross-report comparisons difficult.
    Navy-funded monitoring accomplishments in the HRC and SOCAL 
portions of HSTT from 2009 to 2012 are provided in the Navy's draft 5-
year Comprehensive Report, as required by the 2009 rulemakings and 
available here: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications. Following is a summary of the work 
conducted:
     Conducted over 4,000 hours of visual survey effort;
     Covered over 64,800 nautical miles of ocean;
     Sighted over 256,000 individual marine mammals;
     Taken over 45,500 digital photos and 32 hours of digital 
video;
     Attached 70 satellite tracking tags to individual marine 
mammals; and
     Collected over 25,000 hours of passive acoustic 
recordings.
    Some recent highlights of findings include:
     Increased understanding of Hawaiian monk seal habitat use 
and behavior throughout the Main Hawaiian Islands;
     Estimated received levels and reconstructions of animal 
movements during an ASW training event from the bottom-mounted 
hydrophone arrays at the Pacific Missile Range Facility;

[[Page 7019]]

     Increased knowledge of baseline marine mammal behavior 
information in SOCAL from focal follows of priority cetacean species; 
and
     Observed northern right whale dolphin mother-calf pairs 
for the first time since SOCAL aerial monitoring surveys began in fall 
2008.
    Data collection and analysis within these range complexes is 
ongoing. From 2009 to 2011, Navy lookouts aboard Navy ships reported 
1,262 sightings for an estimated 12,875 marine mammals within the HSTT 
Study Area. These observations were mainly during major at-sea training 
events and there were no reported observations of adverse reactions by 
marine mammals and no dead or injured animals reported associated with 
Navy training activities.

Proposed Monitoring for the HSTT Study Area

    Based on discussions between the Navy and NMFS, future monitoring 
would address the ICMP top-level goals through a collection of specific 
regional and ocean basin studies based on scientific objectives. 
Quantitative metrics of monitoring effort (e.g., 20 days of aerial 
survey) would not be a specific requirement. The adaptive management 
process and reporting requirements would serve as the basis for 
evaluating performance and compliance, primarily considering the 
quality of the work and results produced, as well as peer review and 
publications, and public dissemination of information, reports, and 
data. The strategic planning process would be used to set intermediate 
scientific objectives, identify potential species of interest at a 
regional scale, and evaluate and select specific monitoring projects to 
fund or continue supporting for a given fiscal year. The strategic 
planning process would also address 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.

Ongoing Navy Research

Overview
    The Navy is one of the world's leading organizations in assessing 
the effects of human activities on the marine environment, and provides 
a significant amount of funding and support to marine research, outside 
of the monitoring required by their incidental take authorizations. 
They also develop approaches to ensure that these resources are 
minimally impacted by current and future Navy operations. Navy 
scientists work cooperatively with other government researchers and 
scientists, universities, industry, and non-governmental conservation 
organizations in collecting, evaluating, and modeling information on 
marine resources, including working towards a better understanding of 
marine mammals and sound. From 2004 to 2012, the Navy has provided over 
$230 million for marine species research. The Navy sponsors 70 percent 
of all U.S. research concerning the effects of human-generated sound on 
marine mammals and 50 percent of such research conducted worldwide. 
Major topics of Navy-supported marine species research directly 
applicable to proposed activities within the HSTT Study Area include 
the following:
     Better understanding of marine species distribution and 
important habitat areas;
     Developing methods to detect and monitor marine species 
before and during training and testing activities;
     Better understanding the impacts of sound on marine 
mammals, sea turtles, fish, and birds; and
     Developing tools to model and estimate potential impacts 
of sound.
    It is imperative that the Navy's research and development (R&D) 
efforts related to marine mammals are conducted in an open, transparent 
manner with validated study needs and requirements. The goal of the 
Navy's R&D program is to enable collection and publication of 
scientifically valid research as well as development of techniques and 
tools for Navy, academic, and commercial use. The two Navy 
organizations that account for most funding and oversight of the Navy 
marine mammal research program are the Office of Naval Research (ONR) 
Marine Mammals and Biology Program, and the Office of the Chief of 
Naval Operations (CNO) Energy and Environmental Readiness Division 
(N45) Living Marine Resources (LMR) Program. The primary focus of these 
programs has been on understanding the effects of sound on marine 
mammals, including physiological, behavioral and ecological effects.
    The ONR Marine Mammals and Biology Program supports basic and 
applied research and technology development related to understanding 
the effects of sound on marine mammals, including physiological, 
behavioral, ecological, and population-level effects. Current program 
thrusts include, but are not limited to:
     Monitoring and detection;
     Integrated ecosystem research including sensor and tag 
development;
     Effects of sound on marine life including hearing, 
behavioral response studies, diving and stress physiology, and 
Population Consequences of Acoustic Disturbance (PCAD); and
     Models and databases for environmental compliance.
    To manage some of the Navy's marine mammal research programmatic 
elements, OPNAV N45 developed in 2011 a new Living Marine Resources 
(LMR) Research and Development Program. The mission of the LMR program 
is to develop, demonstrate, and assess information and technology 
solutions to protect living marine resources by minimizing the 
environmental risks of Navy at-sea training and testing activities 
while preserving core Navy readiness capabilities. This mission is 
accomplished by:
     Improving knowledge of the status and trends of marine 
species of concern and the ecosystems of which they are a part;
     Developing the scientific basis for the criteria and 
thresholds to measure the effects of Navy generated sound;
     Improving understanding of underwater sound and sound 
field characterization unique to assessing the biological consequences 
resulting from underwater sound (as opposed to tactical applications of 
underwater sound or propagation loss modeling for military 
communications or tactical applications); and
     Developing technologies and methods to monitor and, where 
possible, mitigate biologically significant consequences to living 
marine resources resulting from naval activities, emphasizing those 
consequences that are most likely to be biologically significant.
    The program is focused on three primary objectives that influence 
program management priorities and directly affect the program's success 
in accomplishing its mission:
    1. Collect, Validate, and Rank R&D Needs: Expand awareness of R&D 
program opportunities within the Navy marine resource community to 
encourage and facilitate the submittal of well-defined and appropriate 
needs statements.
    2. Address High Priority Needs: Ensure that program investments and 
the resulting projects maintain a direct and consistent link to the 
defined user needs.
    3. Transition Solutions and Validate Benefits: Maximize the number 
of program-derived solutions that are successfully transitioned to the 
Fleet and system commands.

[[Page 7020]]

    The LMR program primarily invests in the following areas:
     Developing Data to Support Risk Threshold Criteria;
     Improved Data Collection on Protected Species, Critical 
Habitat within Navy Ranges;
     New Monitoring and Mitigation Technology Demonstrations;
     Database and Model Development; and
     Education and Outreach, Emergent Opportunities.
    The Navy has also developed the technical reports and supporting 
data used for analysis in the HSTT DEIS/OEIS and this proposed rule, 
which include the Navy Marine Species Density Database, Acoustic 
Criteria and Thresholds, and Determination of Acoustic Effects on 
Marine Mammals and Sea Turtles. Furthermore, research cruises by NMFS 
and by academic institutions have received funding from the Navy. For 
instance, LMR currently supports the Marine Mammal Monitoring on Ranges 
program at Pacific Missile Range Facility on Kauai and, along with ONR, 
the multi-year Southern California Behavioral Response Study (http://www.socal-brs.org). All of this research helps in understanding the 
marine environment and the effects that may arise from underwater noise 
in oceans. Further, NMFS is working on a long-term stranding study that 
will be supported by the Navy by way of a funding and information 
sharing component (see below).
Navy Research and Development
    Navy Funded--Both OPNAV N45 and ONR R&D programs have projects 
ongoing within the HSTT Study Area. Some data and results from these 
R&D projects are summarized in the Navy's annual range complex 
monitoring reports, and available on NMFS' Web site (http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications) and the 
Fleet's new marine species monitoring Web site (http://www.navymarinespeciesmonitoring.us). In addition, the Navy's Fleet 
monitoring is coordinated with R&D monitoring in a given region to 
leverage research objectives, assets, and studies where possible under 
the Navy's Integrated Comprehensive Monitoring Program.
    Below are some current Navy R&D funded projects or joint Navy-NMFS/
academic funded projects through 2012 in the HSTT Study Area. Southern 
California:
     Behavioral Response Study (multiple academic, NMFS, 
contract scientists, Navy science organizations, and other 
collaborators; $1.8M funded by OPNAV N45 and ONR)
     Small Boat Based Marine Mammal Surveys in Southern 
California (Scripps Institute of Oceanography, University of California 
San Diego; $400K funded by OPNAV N45)
     Distribution and Demographics of Marine Mammals in SOCAL 
Through Photo-Identification, Genetics, and Satellite Telemetry 
(Cascadia Research Collective; $260K funded by OPNAV N45)
     Blue and Humpback Acoustic Survey Methods (Southwest 
Fisheries Science Center, National Marine Fisheries Service Fisheries 
Science Center, $160K funded by OPNAV N45)
     Tracking Marine Mammals on Southern California Offshore 
ASW Range (SOAR) using Marine Mammal Monitoring on Navy Ranges (M3R) 
(Naval Undersea Warfare Center Newport; $500K funded by OPNAV N45)
    Hawaii:
     Passive Acoustic Methods for Tracking Marine Mammals Using 
Widely-Spaced Bottom Mounted Hydrophones (University of Hawaii; funded 
by ONR)
     Satellite Tagging Odontocetes in the Navy's Pacific 
Missile Range Facility (PMRF) and Kauai (Cascadia Research Collective; 
$150K funded by OPNAV N45)
     Tracking Marine Mammals on PMRF using Marine Mammal 
Monitoring on Navy Ranges (M3R) System (Naval Undersea Warfare Center 
Newport; $290K funded by OPNAV N45)
     Remote Monitoring of Dolphins and Whales in the High Naval 
Activity Areas in Hawaiian Waters (Hawaii Institute of Marine Biology, 
funded by ONR)
    The integration between the Navy's new LMR R&D program and related 
fleet and Systems Command HSTT monitoring would continue and improve 
over the 5-year period with applicable R&D results presented in HSTT 
annual monitoring reports.
    Other National Department of Defense Funded Initiatives--The 
Strategic Environmental Research and Development Program (SERDP) and 
Environmental Security Technology Certification Program (ESTCP) are the 
Department of Defense's environmental research programs, harnessing the 
latest science and technology to improve environmental performance, 
reduce costs, and enhance and sustain mission capabilities. The 
programs respond to environmental technology requirements common to all 
military services, complementing the services' research programs. SERDP 
and ESTCP promote partnerships and collaboration among academia, 
industry, the military services, and other federal agencies. They are 
independent programs managed from a joint office to coordinate the full 
spectrum of efforts, from basic and applied research to field 
demonstration and validation. Beginning in March 2012, an ESTCP project 
that might eventually be applicable to future Navy training and testing 
is the Biodegradable Sonobuoy Decelerators. More information about this 
project can be found at: http://www.serdp.org/Program-Areas/Weapons-Systems-and-Platforms/Waste-Reduction-and-Treatment-in-DoD-Operations/WP-201222/WP-201222/(language)/eng-US).

Adaptive Management

    The final regulations governing the take of marine mammals 
incidental to Navy training and testing activities in the HSTT Study 
Area would contain an adaptive management component carried over from 
previous authorizations. Although better than 5 years ago, our 
understanding of the effects of Navy training and testing activities 
(e.g., MFAS/HFAS, underwater detonations) on marine mammals is still 
relatively limited, and yet the science in this field is evolving 
fairly quickly. These circumstances make the inclusion of an adaptive 
management component both valuable and necessary within the context of 
5-year regulations for activities that have been associated with marine 
mammal mortality in certain circumstances and locations.
    The reporting requirements associated with this proposed rule are 
designed to provide NMFS with monitoring data from the previous year to 
allow NMFS to consider whether any changes are appropriate. NMFS and 
the Navy would meet to discuss the monitoring reports, Navy R&D 
developments, and current science and whether mitigation or monitoring 
modifications 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 reducing adverse effects to marine mammals and 
if the measures are practicable.
    The following are some of the possible sources of applicable data 
to be considered through the adaptive

[[Page 7021]]

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 Navy is currently establishing a strategic planning process 
under the ICMP in coordination with NMFS. The objective of the 
strategic planning process is to guide the continued evolution of Navy 
marine species monitoring towards a single integrated program, 
incorporating expert review and recommendations, and establishing a 
more structured and collaborative framework for evaluating, selecting, 
and implementing future monitoring across the all Navy range complexes. 
The Strategic Plan is intended to be a primary component of the ICMP 
and provide a ``vision'' for navy monitoring across geographic 
regions--serving as guidance for determining how to most efficiently 
and effectively invest the marine species monitoring resources to 
address ICMP top-level goals and satisfy MMPA monitoring requirements. 
This process is being designed to integrate various elements including:
     ICMP top-level goals;
     SAG recommendations;
     Integration of regional scientific expert input;
     Ongoing adaptive management review dialogue between NMFS 
and the Navy;
     Lessons learned from past and future monitoring at Navy 
training and testing ranges; and
     Leveraged research and lessons learned from other Navy 
funded marine science programs.

Reporting

    In order to issue an ITA for an activity, section 101(a)(5)(A) of 
the MMPA states that NMFS must set forth ``requirements pertaining to 
the monitoring and reporting of such taking''. Effective reporting is 
critical both to compliance as well as ensuring that the most value is 
obtained from the required monitoring. Some of the reporting 
requirements are still in development and the final rulemaking may 
contain additional details not contained here. Additionally, proposed 
reporting requirements may be modified, removed, or added based on 
information or comments received during the public comment period. 
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 proposed 
regulations:

General Notification of Injured or Dead Marine Mammals

    Navy personnel would ensure that NMFS (the appropriate Regional 
Stranding Coordinator) is notified immediately (or as soon as clearance 
procedures allow) if an injured or dead marine mammal is found during 
or shortly after, and in the vicinity of, any Navy training exercise 
utilizing MFAS, HFAS, or underwater explosive detonations. The Navy 
would provide NMFS with species identification or a description of the 
animal(s), the condition of the animal(s) (including carcass condition 
if the animal is dead), location, time of first discovery, observed 
behaviors (if alive), and photographs or video (if available). The HSTT 
Stranding Response Plan contains further reporting requirements for 
specific circumstances (http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications).

Annual Monitoring and Exercise Reports

    As noted above, 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 as they become available. Progress and results 
from all monitoring activity conducted within the HSTT Study Area, as 
well as required Major Training Event exercise activity, would be 
summarized in an annual report. A draft of this report would be 
submitted to NMFS for review by April 15 of each year. NMFS would 
review the report and provide comments for incorporation within 3 
months.

Comprehensive Monitoring and Exercise Summary Report

    The Navy would submit to NMFS a draft report that analyzes and 
summarizes all of the multi-year marine mammal monitoring and Major 
Training Event exercise information gathered during training and 
testing exercises for which individual annual reports are required 
under the proposed regulations. This report would be submitted at the 
end of the fourth year of the rule (December 2018), covering activities 
that have occurred through June 1, 2018. The Navy will respond to NMFS 
comments on the draft comprehensive report if submitted within 3 months 
of receipt. The report will be considered final after the Navy has 
addressed NMFS' comments, or three months after the submittal of the 
draft if NMFS does not provide comments.

Estimated Take of Marine Mammals

    In the potential effects section, NMFS' analysis identified the 
lethal responses, physical trauma, sensory impairment (PTS, TTS, and 
acoustic masking), physiological responses (particular stress 
responses), and behavioral responses that could potentially result from 
exposure to MFAS/HFAS or underwater explosive detonations. In this 
section, we will relate the potential effects to marine mammals from 
MFAS/HFAS and underwater detonation of explosives to the MMPA 
regulatory definitions of Level A and Level B Harassment and attempt to 
quantify the effects that might occur from the proposed training and 
testing activities in the Study Area.
    As mentioned previously, behavioral responses are context-
dependent, complex, and influenced to varying degrees by a number of 
factors other than just received level. For example, an animal may 
respond differently to a sound emanating from a ship that is moving 
towards the animal than it would to an identical received level coming 
from a vessel that is moving away, or to a ship traveling at a 
different speed or at a different distance from the animal. At greater 
distances, though, the nature of vessel movements could also 
potentially not have any effect on the animal's response to the sound. 
In any case, a full description of the suite of factors that elicited a 
behavioral response would require a mention of the vicinity, speed and 
movement of the vessel, or other factors. So, while sound sources and 
the received levels are the primary focus of the analysis and those 
that are laid out quantitatively in the regulatory text, it is with the 
understanding that other factors related to the training are sometimes 
contributing to the behavioral responses of marine mammals, although 
they cannot be quantified.

Definition of Harassment

    As mentioned previously, with respect to military readiness 
activities, section 3(18)(B) of 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

[[Page 7022]]

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].

Level B Harassment

    Of the potential effects that were described earlier in this 
document, the following are the types of effects that fall into the 
Level B Harassment category:
    Behavioral Harassment--Behavioral disturbance that rises to the 
level described in the definition above, when resulting from exposures 
to non-impulsive or impulsive sound, is considered Level B Harassment. 
Some of the lower level physiological stress responses discussed 
earlier would also 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. 
When Level B Harassment is predicted based on estimated behavioral 
responses, those takes may have a stress-related physiological 
component as well.
    Earlier in this document, we described the Southall et al., (2007) 
severity scaling system and listed some examples of the three broad 
categories of behaviors: 0-3 (Minor and/or brief behaviors); 4-6 
(Behaviors with higher potential to affect foraging, reproduction, or 
survival); 7-9 (Behaviors considered likely to affect the 
aforementioned vital rates). Generally speaking, MMPA Level B 
Harassment, as defined in this document, would include the behaviors 
described in the 7-9 category, and a subset, dependent on context and 
other considerations, of the behaviors described in the 4-6 category. 
Behavioral harassment does not generally include behaviors ranked 0-3 
in Southall et al., (2007).
    Acoustic Masking and Communication Impairment--Acoustic masking is 
considered Level B Harassment as it can disrupt natural behavioral 
patterns by interrupting or limiting the marine mammal's receipt or 
transmittal of important information or environmental cues.
    Temporary Threshold Shift (TTS)--As discussed previously, TTS can 
affect how an animal behaves in response to the environment, including 
conspecifics, predators, and prey. The following physiological 
mechanisms are thought to play a role in inducing auditory fatigue: 
effects to sensory hair cells in the inner ear that reduce their 
sensitivity, modification of the chemical environment within the 
sensory cells; residual muscular activity in the middle ear, 
displacement of certain inner ear membranes; increased blood flow; and 
post-stimulatory reduction in both efferent and sensory neural output. 
Ward (1997) suggested that when these effects result in TTS rather than 
PTS, they are within the normal bounds of physiological variability and 
tolerance and do not represent a physical injury. Additionally, 
Southall et al. (2007) indicate that although PTS is a tissue injury, 
TTS is not because the reduced hearing sensitivity following exposure 
to intense sound results primarily from fatigue, not loss, of cochlear 
hair cells and supporting structures and is reversible. Accordingly, 
NMFS classifies TTS (when resulting from exposure to sonar and other 
active acoustic sources and explosives and other impulsive sources) as 
Level B Harassment, not Level A Harassment (injury).

Level A Harassment

    Of the potential effects that were described earlier, following are 
the types of effects that fall into the Level A Harassment category:
    Permanent Threshold Shift (PTS)--PTS (resulting either from 
exposure to MFAS/HFAS or explosive detonations) is irreversible and 
considered an injury. PTS results from exposure to intense sounds that 
cause a permanent loss of inner or outer cochlear hair cells or exceed 
the elastic limits of certain tissues and membranes in the middle and 
inner ears and result in changes in the chemical composition of the 
inner ear fluids.
    Tissue Damage due to Acoustically Mediated Bubble Growth--A few 
theories suggest ways in which gas bubbles become enlarged through 
exposure to intense sounds (MFAS/HFAS) to the point where tissue damage 
results. In rectified diffusion, exposure to a sound field would cause 
bubbles to increase in size. A short duration of sonar pings (such as 
that which an animal exposed to MFAS would be most likely to encounter) 
would not likely be long enough to drive bubble growth to any 
substantial size. Alternately, bubbles could be destabilized by high-
level sound exposures such that bubble growth then occurs through 
static diffusion of gas out of the tissues. The degree of 
supersaturation and exposure levels observed to cause microbubble 
destabilization are unlikely to occur, either alone or in concert 
because of how close an animal would need to be to the sound source to 
be exposed to high enough levels, especially considering the likely 
avoidance of the sound source and the required mitigation. Still, 
possible tissue damage from either of these processes would be 
considered an injury.
    Tissue Damage due to Behaviorally Mediated Bubble Growth--Several 
authors suggest mechanisms in which marine mammals could behaviorally 
respond to exposure to MFAS/HFAS by altering their dive patterns 
(unusually rapid ascent, unusually long series of surface dives, etc.) 
in a manner that might result in unusual bubble formation or growth 
ultimately resulting in tissue damage. In this scenario, the rate of 
ascent would need to be sufficiently rapid to compromise behavioral or 
physiological protections against nitrogen bubble formation. There is 
considerable disagreement among scientists as to the likelihood of this 
phenomenon (Piantadosi and Thalmann, 2004; Evans and Miller, 2003). 
Although it has been argued that traumas from recent beaked whale 
strandings are consistent with gas emboli and bubble-induced tissue 
separations (Jepson et al., 2003; Fernandez et al., 2005), nitrogen 
bubble formation as the cause of the traumas has not been verified. If 
tissue damage does occur by this phenomenon, it would be considered an 
injury.
    Physical Disruption of Tissues Resulting From Explosive Shock 
Wave--Physical damage of tissues resulting from a shock wave (from an 
explosive detonation) is classified as an injury. Blast effects are 
greatest at the gas-liquid interface (Landsberg, 2000) and gas-
containing organs, particularly the lungs and gastrointestinal tract, 
are especially susceptible (Goertner, 1982; Hill, 1978; Yelverton et 
al., 1973). Nasal sacs, larynx, pharynx, trachea, and lungs may be 
damaged by compression/expansion caused by the oscillations of the 
blast gas bubble (Reidenberg and Laitman, 2003). Severe damage (from 
the shock wave) to the ears can include tympanic membrane rupture, 
fracture of the ossicles, damage to the cochlea, hemorrhage, and 
cerebrospinal fluid leakage into the middle ear.
    Vessel or Ordnance Strike--Vessel strike or ordnance strike 
associated with the specified activities would be considered Level A 
Harassment, serious injury, or mortality.

Take Criteria

    For the purposes of an MMPA authorization, three types of take are 
identified: Level B Harassment; Level A Harassment; and mortality (or 
serious injury leading to mortality). The categories of marine mammal 
responses (physiological and behavioral) that fall

[[Page 7023]]

into the two harassment categories were described in the previous 
section.
    Because the physiological and behavioral responses of the majority 
of the marine mammals exposed to non-impulse and impulse sounds cannot 
be easily detected or measured, and because NMFS must authorize take 
prior to the impacts to marine mammals, a method is needed to estimate 
the number of individuals that will be taken, pursuant to the MMPA, 
based on the proposed action. To this end, NMFS developed acoustic 
criteria that estimate at what received level (when exposed to non-
impulse or impulse sounds) Level B Harassment and Level A Harassment of 
marine mammals would occur. The acoustic criteria for non-impulse and 
impulse sounds are discussed below.
    Level B Harassment Threshold (TTS)--Behavioral disturbance, 
acoustic masking, and TTS are all considered Level B Harassment. Marine 
mammals would usually be behaviorally disturbed at lower received 
levels than those at which they would likely sustain TTS, so the levels 
at which behavioral disturbance are likely to occur is considered the 
onset of Level B Harassment. The behavioral responses of marine mammals 
to sound are variable, context specific, and, therefore, difficult to 
quantify (see Risk Function section, below). Alternately, TTS is a 
physiological effect that has been studied and quantified in laboratory 
conditions. Because data exist to support an estimate of the received 
levels at which marine mammals will incur TTS, NMFS uses an acoustic 
criteria to estimate the number of marine mammals that might sustain 
TTS. TTS is a subset of Level B Harassment (along with sub-TTS 
behavioral harassment) and we are not specifically required to estimate 
those numbers; however, the more specifically we can estimate the 
affected marine mammal responses, the better the analysis.
    Level A Harassment Threshold (PTS)--For acoustic effects, because 
the tissues of the ear appear to be the most susceptible to the 
physiological effects of sound, and because threshold shifts tend to 
occur at lower exposures than other more serious auditory effects, NMFS 
has determined that PTS is the best indicator for the smallest degree 
of injury that can be measured. Therefore, the acoustic exposure 
associated with onset-PTS is used to define the lower limit of Level A 
Harassment.
    PTS data do not currently exist for marine mammals and are unlikely 
to be obtained due to ethical concerns. However, PTS levels for these 
animals may be estimated using TTS data from marine mammals and 
relationships between TTS and PTS that have been determined through 
study of terrestrial mammals.
    We note here that behaviorally mediated injuries (such as those 
that have been hypothesized as the cause of some beaked whale 
strandings) could potentially occur in response to received levels 
lower than those believed to directly result in tissue damage. As 
mentioned previously, data to support a quantitative estimate of these 
potential effects (for which the exact mechanism is not known and in 
which factors other than received level may play a significant role) 
does not exist. However, based on the number of years (more than 60) 
and number of hours of MFAS per year that the U.S. (and other 
countries) has operated compared to the reported (and verified) cases 
of associated marine mammal strandings, NMFS believes that the 
probability of these types of injuries is very low. Tables 13 and 14 
provide a summary of non-impulsive thresholds to TTS and PTS for marine 
mammals. A detailed explanation of how these thresholds were derived is 
provided in the HSTT DEIS/OEIS Criteria and Thresholds Technical Report 
(http://hstteis.com/DocumentsandReferences/HSTTDocuments/SupportingTechnicalDocuments.aspx) and summarized in Chapter 6 of the 
Navy's LOA application (http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications).

                          Table 13--Onset TTS and PTS Thresholds for Non-Impulse Sound
----------------------------------------------------------------------------------------------------------------
                Group                          Species                 Onset TTS                Onset PTS
----------------------------------------------------------------------------------------------------------------
Low-Frequency Cetaceans..............  All mysticetes.........  178 dB re 1[mu]Pa2-      198 dB re 1[mu]Pa2-
                                                                 sec(LFII).               sec(LFII).
Mid-Frequency Cetaceans..............  Most delphinids, beaked  178 dB re 1[mu]Pa2-      198 dB re 1[mu]Pa2-
                                        whales, medium and       sec(MFII).               sec(MFII).
                                        large toothed whales.
High-Frequency Cetaceans.............  Porpoises, Kogia spp...  152 dB re 1[mu]Pa2-      172 dB re 1[mu]Pa2-
                                                                 sec(HFII).               secSEL (HFII).
Phocidae In-water....................  Harbor, Hawaiian monk,   183 dB re 1[mu]Pa2-      197 dB re 1[mu]Pa2-
                                        elephant seals.          sec(PWI).                sec(PWI).
Otariidae & Obodenidae In-water......  Sea lions and fur seals  206 dB re 1[mu]Pa2-      220 dB re 1[mu]Pa2-
                                                                 sec(OWI).                sec(OWI).
Mustelidae In-water..................  Sea otters.
----------------------------------------------------------------------------------------------------------------
LFII, MFII, HFII: New compound Type II weighting functions; PWI, OWI: Original Type I (Southall et al. 2007) for
  pinniped and mustelid in water.


         Table 14--Impulsive Sound Explosive Criteria and Thresholds for Predicting Injury and Mortality
----------------------------------------------------------------------------------------------------------------
                                                                   Slight injury
            Group                   Species     --------------------------------------------------   Mortality
                                                        PTS           GI Tract          Lung
----------------------------------------------------------------------------------------------------------------
Low-frequency Cetaceans......  All mysticetes..  187 dB SEL        237 dB SPL or   Equation 1....  Equation 2.
                                                  (LFII) or 230     104 psi.
                                                  dB Peak SPL.
Mid-frequency Cetaceans......  Most delphinids,  187 dB SEL
                                medium and        (MFII) or 230
                                large toothed     dB Peak SPL.
                                whales.
High-frequency Cetaceans.....  Porpoises and     161 dB SEL
                                Kogia spp.        (HFII) or 201
                                                  dB Peak SPL.
Phocidae.....................  Hawaiian monk,    192 dB SEL (PWI)
                                elephant, and     or 218 dB Peak
                                harbor seal.      SPL.
Otariidae....................  Sea lions and     215 dB SEL (OWI)
                                fur seals.        or 218 dB Peak
                                                  SPL.
Mustelidae...................  Sea otters.
----------------------------------------------------------------------------------------------------------------


[[Page 7024]]

    Equation 1:

= 39.1M1/3 (1+[DRm/10.081]) 1/2 Pa-sec
    Equation 2:

= 91.4M1/3 (1+[DRm/10.081])1/2 Pa-sec



Where: M = mass of the animals in kg.
DRm = depth of the receiver (animal) in meters.

    Level B Harassment Risk Function (Behavioral Harassment)--In 2006, 
NMFS issued the first MMPA authorization to allow the take of marine 
mammals incidental to MFAS (to the Navy for RIMPAC). For that 
authorization, NMFS used 173 dB SEL as the criterion for the onset of 
behavioral harassment (Level B Harassment). This type of single number 
criterion is referred to as a step function, in which (in this example) 
all animals estimated to be exposed to received levels above 173 db SEL 
would be predicted to be taken by Level B Harassment and all animals 
exposed to less than 173 dB SEL would not be taken by Level B 
Harassment. As mentioned previously, marine mammal behavioral responses 
to sound are highly variable and context specific (affected by 
differences in acoustic conditions; differences between species and 
populations; differences in gender, age, reproductive status, or social 
behavior; or the prior experience of the individuals), which does not 
support the use of a step function to estimate behavioral harassment.
    Unlike step functions, acoustic risk continuum functions (which are 
also called ``exposure-response functions'' or ``dose-response 
functions'' in other risk assessment contexts) allow for probability of 
a response that NMFS would classify as harassment to occur over a range 
of possible received levels (instead of one number) and assume that the 
probability of a response depends first on the ``dose'' (in this case, 
the received level of sound) and that the probability of a response 
increases as the ``dose'' increases (see Figure 1a). In January 2009, 
NMFS issued three final rules governing the incidental take of marine 
mammals (within Navy's HRC, SOCAL, and Atlantic Fleet Active Sonar 
Training (AFAST)) that used a risk continuum to estimate the percent of 
marine mammals exposed to various levels of MFAS that would respond in 
a manner NMFS considers harassment.
    The Navy and NMFS have previously used acoustic risk functions to 
estimate the probable responses of marine mammals to acoustic exposures 
for other training and research programs. Examples of previous 
application include the Navy FEISs on the SURTASS LFA sonar (U.S. 
Department of the Navy, 2001c); the North Pacific Acoustic Laboratory 
experiments conducted off the Island of Kauai (Office of Naval 
Research, 2001); and the Supplemental EIS for SURTASS LFA sonar (U.S. 
Department of the Navy, 2007d). As discussed earlier, factors other 
than received level (such as distance from or bearing to the sound 
source, context of animal at time of exposure) can affect the way that 
marine mammals respond; however, data to support a quantitative 
analysis of those (and other factors) do not currently exist. NMFS will 
continue to modify these criteria as new data become available and can 
be appropriately and effectively incorporated.
    The particular acoustic risk functions developed by NMFS and the 
Navy (see Figures 1a and 1b) estimate the probability of behavioral 
responses to MFAS/HFAS (interpreted as the percentage of the exposed 
population) that NMFS would classify as harassment for the purposes of 
the MMPA given exposure to specific received levels of MFAS/HFAS. The 
mathematical function (below) underlying this curve is a cumulative 
probability distribution adapted from a solution in Feller (1968) and 
was also used in predicting risk for the Navy's SURTASS LFA MMPA 
authorization as well.
[GRAPHIC] [TIFF OMITTED] TP31JA13.001

Where:

R = Risk (0-1.0)
L = Received level (dB re: 1 [mu]Pa).
B = Basement received level = 120 dB re: 1 [mu]Pa.
K = Received level increment above B where 50-percent risk = 45 dB 
re: 1 [mu]Pa.
A = Risk transition sharpness parameter = 10 (odontocetes and 
pinnipeds) or 8 (mysticetes).

    Detailed information on the above equation and its parameters is 
available in the HSTT DEIS/OEIS and previous Navy documents listed 
above.
    The inclusion of a special behavioral response criterion for beaked 
whales of the family Ziphiidae is new to these criteria. It has been 
speculated that beaked whales might have unusual sensitivities to sonar 
sound due to their likelihood of stranding in conjunction with MFAS 
use, even in areas where other species were more abundant (D'Amico et 
al. 2009), but there were not sufficient data to support a separate 
treatment for beaked whales until recently. With the recent publication 
of results from Blainville's beaked whale monitoring and experimental 
exposure studies on the instrumented Atlantic Undersea Test and 
Evaluation Center range in the Bahamas (McCarthy et al. 2011; Tyack et 
al. 2011), there are now statistically strong data suggesting that 
beaked whales tend to avoid both actual naval MFAS in real anti-
submarine training scenarios as well as sonar-like signals and other 
signals used during controlled sound exposure studies in the same area. 
An unweighted 140 dB re 1 [mu]Pa sound pressure level threshold has 
been adopted by the Navy for significant behavioral effects for all 
beaked whales (family: Ziphiidae).
    If more than one explosive event occurs within any given 24-hour 
period within a training or testing event, behavioral criteria are 
applied to predict the number of animals that may be taken by Level B 
Harassment. For multiple explosive events the behavioral threshold used 
in this analysis is 5 dB less than the TTS onset threshold (in sound 
exposure level). This value is derived from observed onsets of 
behavioral response by test subjects (bottlenose dolphins) during non-
impulse TTS testing (Schlundt et al. 2000). Some multiple explosive 
events, such as certain naval gunnery exercises, may be treated as a 
single impulsive event because a few explosions occur closely spaced 
within a very short period of time (a few seconds). For single impulses 
at received sound levels below hearing loss thresholds, the most likely 
behavioral response is a brief alerting or orienting response. Since no 
further sounds follow the initial brief impulses, Level B take in the 
form of behavioral harassment beyond that associated with potential TTS 
would not be expected to occur. Explosive criteria and thresholds are 
summarized in Table 15 and further detailed in the Navy's LOA 
application.
    Since impulse events can be quite short, it may be possible to 
accumulate multiple received impulses at sound pressure levels 
considerably above the energy-based criterion and still not be 
considered a behavioral take. The Navy treats all individual received 
impulses as if they were one second long for the purposes of 
calculating cumulative sound exposure level for multiple impulse 
events. For example, five air gun impulses, each 0.1 second long, 
received at 178 dB sound pressure level would equal a 175 dB sound 
exposure level, and would not be predicted as leading to a take. 
However, if the five 0.1 second pulses are treated as a 5 second 
exposure, it would yield an adjusted value of approximately 180 dB, 
exceeding the threshold. For impulses

[[Page 7025]]

associated with explosions that have durations of a few microseconds, 
this assumption greatly overestimates effects based on sound exposure 
level metrics such as TTS and PTS and behavioral responses. Appropriate 
weighting values will be applied to the received impulse in one-third 
octave bands and the energy summed to produce a total weighted sound 
exposure level value. For impulsive behavioral criteria, the Navy's new 
weighting functions (detailed in the LOA application) are applied to 
the received sound level before being compared to the threshold.

                                                      Table 15-- Explosive Criteria and Thresholds
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                      Slight injury
              Group                       Species       ------------------------------------------------------------------------        Mortality
                                                                  PTS                  GI Tract                   Lung
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low Frequency Cetaceans..........  All mysticetes......  187 dB SEL (LFII) or  237 dB SPL or 104 psi..  Equation 1.............  Equation 2.
                                                          230 dB Peak SPL.
Mid-Frequency Cetaceans..........  Most delphinids,      187 dB SEL (MFII) or
                                    medium and large      230 dB Peak SPL.
                                    toothed whales.
High Frequency Cetaceans.........  Porpoises and Kogia   161 dB SEL (HFII) or
                                    spp.                  201dB Peak SPL.
Phocidae.........................  Hawaiian monk,        192 dB SEL (PWI) or
                                    elephant, and         218 dB Peak SPL.
                                    harbor seal.
Otariidae........................  Sea lions and Fur     215 dB SEL (OWI) or
                                    seals.                218 dB Peak SPL.
Mustelidae.......................  Sea Otters.
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                   [GRAPHIC] [TIFF OMITTED] TP31JA13.002
                                   
    Existing NMFS criteria was applied to sounds generated by pile 
driving and airguns (Table 16).

                                Table 16--Thresholds for Pile Driving and Airguns
----------------------------------------------------------------------------------------------------------------
                                     Underwater vibratory pile driving      Underwater impact pile driving and
                                   criteria (sound pressure level, dB re  airgun criteria (sound pressure level,
                                                 1 [mu]Pa)                            dB re 1 [mu]Pa)
         Species groups          -------------------------------------------------------------------------------
                                                            Level B                                 Level B
                                    Level A injury        disturbance       Level A injury        disturbance
                                       threshold           threshold           threshold           threshold
----------------------------------------------------------------------------------------------------------------
Cetaceans (whales, dolphins,      180 dB rms........  120 dB rms........  180 dB rms........  160 dB rms.
 porpoises).
Pinnipeds (seals)...............  190 dB rms........  120 dB rms........  190 dB rms........  160 dB rms.
----------------------------------------------------------------------------------------------------------------

Quantitative Modeling for Impulsive and Non-Impulsive Sound

    The Navy performed a quantitative analysis to estimate the number 
of marine mammals that could be harassed by acoustic sources or 
explosives used during Navy training and testing activities. Inputs to 
the quantitative analysis included marine mammal density estimates; 
marine mammal depth occurrence distributions; oceanographic and 
environmental data; marine mammal hearing data; and criteria and 
thresholds for levels of potential effects. The quantitative analysis 
consists of computer-modeled estimates and a post-model analysis to 
determine the number of potential mortalities and harassments. The 
model calculates sound energy propagation from sonars, 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 received by a marine mammal exceeds the thresholds for 
effects. The model estimates are then further analyzed to consider 
animal avoidance and implementation of mitigation measures, resulting 
in final estimates of effects due to Navy training and testing. This 
process results in a reduction to take numbers and is detailed in 
Chapter 6 (section 6.3) of the Navy's application.
    A number of computer models and mathematical equations can be used 
to predict how energy spreads from a sound source (e.g., sonar or 
underwater detonation) to a receiver (e.g., dolphin or sea turtle). 
Basic underwater sound models calculate the overlap of energy and 
marine life using assumptions that account for the many, variable, and 
often unknown factors that can greatly influence the result. 
Assumptions in previous Navy models have intentionally erred on the 
side of overestimation when there are unknowns or when the addition of 
other variables was not likely to substantively change the final 
analysis. For example, because the ocean environment is extremely 
dynamic and information is often limited to a synthesis of data 
gathered over wide areas and requiring many years of research, known 
information tends to be an average of a seasonal or annual variation. 
The Equatorial Pacific El Nino disruption of the ocean-atmosphere 
system is an example of dynamic change where unusually warm ocean 
temperatures are likely to redistribute marine life and alter the 
propagation of underwater sound energy. Previous Navy modeling 
therefore made some assumptions

[[Page 7026]]

indicative of a maximum theoretical propagation for sound energy (such 
as a perfectly reflective ocean surface and a flat seafloor). More 
complex computer models build upon basic modeling by factoring in 
additional variables in an effort to be more accurate by accounting for 
such things as bathymetry and an animal's likely presence at various 
depths.
    The Navy has developed a set of data and new software tools for 
quantification of estimated marine mammal impacts from Navy activities. 
This new approach is the resulting evolution of the basic model 
previously used by the Navy and reflects a more complex modeling 
approach as described below. Although this more complex computer 
modeling approach accounts for various environmental factors affecting 
acoustic propagation, the current software tools do not consider the 
likelihood that a marine mammal would attempt to avoid repeated 
exposures to a sound or avoid an area of intense activity where a 
training or testing event may be focused. Additionally, the software 
tools do not consider the implementation of mitigation (e.g., stopping 
sonar transmissions when a marine mammal is within a certain distance 
of a ship or range clearance prior to detonations). In both of these 
situations, naval activities are modeled as though an activity would 
occur regardless of proximity to marine mammals and without any 
horizontal movement by the animal away from the sound source or human 
activities (e.g., without accounting for likely animal avoidance). 
Therefore, 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.
    The quantified results of the marine mammal acoustic effects 
analysis presented in the Navy's LOA application differ from the 
quantified results presented in the HSTT DEIS/OEIS. Presentation of the 
results in this new manner for MMPA, ESA, and other regulatory analyses 
is well within the framework of the previous NEPA analyses presented in 
the DEIS. The differences are due to three main factors: (1) 
Administrative corrections to the modeling inputs for training and 
testing; (2) use of a more accurate seasonal density for the species 
(short-beaked common dolphins) having the highest abundance of any 
marine mammal in the Study Area; and (3) additional post-model 
quantification to further refine the numerical analysis of acoustic 
effects so as to include animal avoidance of sound sources, avoidance 
of areas of activity before use of a sound source or explosive, and 
implementation of mitigation. This additional quantification was in 
direct response to public comments received on the HSTT DEIS/OEIS with 
regard to a somewhat universal misunderstanding of the numbers 
presented as modeling results. These comments indicated that many 
readers believed the modeling effects numbers presented in the tables 
were the entire acoustic impact analysis. Furthermore, it was clear 
that these same readers had missed the critical subsequent qualitative 
analysis required to accurately interpret those numbers since the model 
does not account for animal avoidance of repeated explosive exposures, 
movement, or standard Navy mitigations. In response to these comments, 
the numbers presented in Navy's LOA application will be reflected in 
the HSTT FEIS/OEIS to more fully quantify the analyzed effects to 
marine mammals. The differences between the HSTT DEIS/OEIS and the 
Navy's LOA application reflect reductions in the analyzed mortality 
takes, Level A takes, and Level B takes. The Navy has advised NMFS that 
all comments received on the proposed rule that address (1) 
Administrative corrections to the modeling inputs for training and 
testing; (2) use of more accurate seasonal density data; and (3) post-
model quantification based on animal avoidance of sound sources and 
mitigation will be reviewed and addressed by the Navy in the HSTT FEIS/
OEIS.
    The steps of the quantitative analysis of acoustic effects, the 
values that went into the Navy's model, and the resulting ranges to 
effects are detailed in Chapter 6 of the Navy's LOA application (http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications).

Take Request

    The HSTT DEIS/OEIS considered all training and testing activities 
proposed to occur in the Study Area that have the potential to result 
in the MMPA defined take of marine mammals. The stressors associated 
with these activities included the following:
     Acoustic (sonar and other active non-impulse sources, 
explosives, pile driving, swimmer defense airguns, weapons firing, 
launch and impact noise, vessel noise, aircraft noise);
     Energy (electromagnetic devices);
     Physical disturbance or strikes (vessels, in-water 
devices, military expended materials, seafloor devices);
     Entanglement (fiber optic cables, guidance wires, 
parachutes);
     Ingestion (munitions, military expended materials other 
than munitions); and
     Indirect stressors (risk to monk seals from Navy 
California sea lions from the transmission of disease or parasites).
    The Navy determined, and NMFS agrees, that three stressors could 
potentially result in the incidental taking of marine mammals from 
training and testing activities within the Study Area: (1) Non-
impulsive stressors (sonar and other active acoustic sources), (2) 
impulsive stressors (explosives, pile driving and removal), and (3) 
vessel strikes. Non-impulsive and impulsive stressors have the 
potential to result in incidental takes of marine mammals by 
harassment, injury, or mortality. Vessel strikes have the potential to 
result in incidental take from direct injury and/or mortality.
    Training Activities--Based on the Navy's model and post-model 
analysis (described in detail in Chapter 6 of their LOA application), 
Table 18 summarizes the Navy's take request for training activities for 
an annual maximum year (a notional 12-month period when all annual and 
non-annual events could occur) and the summation over a 5-year period 
(annual events occurring five times and non-annual events occurring 
three times). Table 19 summarizes the Navy's take request for training 
activities by species from the modeling estimates.
    While the Navy does not anticipate any marine mammal strandings or 
that the mortalities predicted by the acoustic modeling would occur, 
the Navy requests annual authorization for take by mortality of up to 
seven small odontocetes (i.e., dolphins) and pinnipeds to include any 
combination of such species that may be present in the Study Area. 
While the Navy does not anticipate any beaked whale strandings or 
mortalities from sonar and other active sources, in order to account 
for unforeseen circumstances that could lead to such effects the Navy 
requests the annual take, by mortality, of two beaked whales as part of 
training activities.
    Vessel strike to marine mammals is not associated with any specific 
training activity but rather a limited, sporadic, and accidental result 
of Navy vessel movement within the Study Area. 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 Study Area, the 
Navy is seeking take authorization in the event a Navy vessel strike 
does occur while conducting training. The Navy's take authorization

[[Page 7027]]

request is based on the probabilities of whale strikes suggested by the 
data from NMFS Southwest Regional Office, NMFS Pacific Islands Regional 
Office, the Navy, and the calculations detailed in Chapter 6 of the 
Navy's LOA application. The number of Navy and commercial whale strikes 
for which the species has been positively identified suggests that the 
probability of striking a gray whale in the SOCAL Range Complex and 
humpback whale in the HRC is greater than striking other species. 
However, since species identification has not been possible in most 
vessel strike cases, the Navy cannot quantifiably predict what species 
may be taken. Therefore, the Navy seeks take authorization by vessel 
strike for any combined number of large whale species to include gray 
whale, fin whale, blue whale, humpback whale, Bryde's whale, sei whale, 
minke whale, or sperm whale. The Navy requests takes of large marine 
mammals over the course of the 5-year regulations from training 
activities as discussed below:
     The take by vessel strike during training activities in 
any given year of no more than four large whales total of any 
combination of species including gray whale, fin whale, blue whale, 
humpback whale, Bryde's whale, sei whale, minke whale, or sperm whale. 
The four takes per year requested would be no more than two of any one 
species of blue whale, fin whale, humpback whale, sei whale, or sperm 
whale in any given year.
     The take by vessel strike of no more than 12 large whales 
from training activities over the course of the five years of the HSTT 
regulations.
    Over a period of 20 years from 1991 to 2010 there have been a total 
of 16 Navy vessel strikes in SOCAL, and five Navy vessel strikes in 
HRC. It should be noted that two of the five HRC Navy strikes were by 
<12-meter workboats vice larger Navy ships. In terms of the 16 
consecutive 5-year periods in the last 20 years, no single 5-year 
period exceeded ten whales struck within SOCAL and HRC (periods from 
2000-2004 and 2001-2005). For Navy vessel strikes in SOCAL, there were 
six consecutive 5-year periods with six or more whales struck (1997-
2001, 1998-2002, 1999-2003, 2000-2004, 2001-2005, and 2002-2006), and 
no more than three whales struck in the last 5-year period from 2006-
2010. No whales have been struck by Navy vessels in SOCAL since 2009. 
For Navy vessel strikes in the HRC for the same time period, there was 
one 5-year period when three whales were struck (2003-2007), seven 
periods when two whales were struck, five periods when one whale was 
struck, and three periods when no whales were struck. Within the data 
set analyzed for HRC through 2010, no whales have been struck by a Navy 
vessel since 2008. Also as discussed in Chapter 6 of the Navy's LOA 
application, the Poisson probability of striking as many as two large 
whales in the SOCAL portion of the HSTT is only 14 percent per year, 
and the probability of striking two large whales in the HRC portion of 
the HSTT is only 2 percent.

                   Table 17--Summary of Annual and 5-Year Take Request for Training Activities
----------------------------------------------------------------------------------------------------------------
                                                                            Training activities
                                                          ------------------------------------------------------
           MMPA Category                    Source            Annual authorization        5-Year authorization
                                                                   sought \1\                  sought \2\
----------------------------------------------------------------------------------------------------------------
Mortality.........................  Impulse..............  7 mortalities applicable    35 mortalities applicable
                                                            to any small odontocete     to any small odontocete
                                                            or pinniped species.        or pinniped species over
                                                                                        five years.
                                    Unspecified \3\......  2 mortalities to beaked     10 mortalities to beaked
                                                            whales \3\.                 whales over five
                                                                                        years.\3\
                                    Vessel strike........  No more than 4 large whale  No more than 12 large
                                                            mortalities in any given    whale mortalities over
                                                            year \4\.                   five years.\4\
Level A...........................  Impulse and Non-       266--Species specific data  1,314--Species specific
                                     Impulse.               shown in Table 19.          data shown in Table 19.
Level B...........................  Impulse and Non-       1,691,123--Species          8,398,931--Species
                                     Impulse.               specific data shown in      specific data shown in
                                                            Table 19.                   Table 19.
----------------------------------------------------------------------------------------------------------------
\1\ These numbers constitute the total for an annual maximum year (a notional 12-month period when all annual
  and non-annual events could occur) in which a RIMPAC exercise and Civilian Port Defense events would occur in
  Hawaii and SOCAL.
\2\ These numbers constitute the summation over a 5-year period with annual events occurring five times and non-
  annual events occurring three times.
\3\ The Navy's NAEMO model did not quantitatively predict these mortalities. Navy, however, is seeking this
  particular authorization given sensitivities these species may have to anthropogenic activities. Request
  includes 2 Ziphidae beaked whale annually to include any combination of Cuvier's beaked whale, Baird's beaked
  whale, Longman's beaked whale, and unspecified Mesoplodon sp. (not to exceed 10 beaked whales total over the 5-
  year length of requested authorization).
\4\ The Navy cannot quantifiably predict that proposed takes from training will be of any particular species,
  and therefore seeks take authorization for any combination of large whale species (gray whale, fin whale, blue
  whale, humpback whale, Bryde's whale, sei whale, minke whale, or sperm whale), but of the four takes per year
  no more than two of any one species of blue whale, fin whale, humpback whale, sei whale, or sperm whale is
  requested.


        Table 18--Species-Specific Take Request From Modeling Estimates of Impulsive and Non-Impulsive Source Effects for All Training Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                             Annually \1\                 Total over 5-year rule \2\
                    Species                                   Stock              -----------------------------------------------------------------------
                                                                                    Level B     Level A    Mortality    Level B     Level A    Mortality
--------------------------------------------------------------------------------------------------------------------------------------------------------
Blue whale....................................  Eastern North Pacific...........       4,145           0           0      20,725           0           0
                                                 Central North Pacific..........         180           0           0         834           0           0
Fin whale.....................................  California, Oregon, & Washington       1,528           0           0       7,640           0           0
                                                Hawaiian........................         191           0           0         891           0           0
Humpback whale................................  California, Oregon, & Washington       1,081           0           0       5,405           0           0
                                                Central North Pacific...........       8,192           0           0      40,960           0           0

[[Page 7028]]

 
Sei whale.....................................  Eastern North Pacific...........         146           0           0         730           0           0
                                                Hawaiian........................         484           0           0       2,266           0           0
Sperm whale...................................  California, Oregon, & Washington       1,958           0           0       9,790           0           0
                                                Hawaiian........................       1,374           0           0       6,130           0           0
Guadalupe fur seal............................  Mexico..........................       2,603           0           0      13,015           0           0
Hawaiian monk seal............................  Hawaiian........................       1,292           0           0       6,334           0           0
Bryde's whale.................................  Eastern Tropical Pacific........         112           0           0         560           0           0
                                                Hawaiian........................         137           0           0         637           0           0
Gray whale....................................  Eastern North Pacific...........       9,560           2           0      47,800          10           0
Minke whale...................................  California, Oregon, & Washington         359           0           0       1,795           0           0
                                                Hawaiian........................         447           0           0       2,235           0           0
Baird's beaked whale..........................  California, Oregon, & Washington       4,420           0           0      22,100           0           0
Blainville's beaked whale.....................  Hawaiian........................      10,316           0           0      48,172           0           0
Bottlenose dolphin............................  California coastal..............         521           0           0       2,605           0           0
                                                California, Oregon & Washington       26,618           0           0     133,090           0           0
                                                 offshore.
                                                Hawaii Stock Complex............       5,163           0           0      22,895           0           0
Cuvier's beaked whale.........................  California, Oregon, & Washington      13,353           0           0      66,765           0           0
                                                Hawaiian........................      52,893           0           0     248,025           0           0
Dwarf sperm whale.............................  Hawaiian........................      22,359          46           0     101,291         214           0
Dall's porpoise...............................  California, Oregon, & Washington      36,891          47           0     184,455         235           0
False killer whale............................  Hawaii Insular..................          49           0           0         220           0           0
                                                Hawaii Pelagic..................         480           0           0       2,116           0           0
                                                Northwest Hawaiian Islands......         177           0           0         776           0           0
Fraser's dolphin..............................  Hawaiian........................       2,009           0           0       8,809           0           0
Killer whale..................................  Eastern North Pacific offshore/          321           0           0       1,605           0           0
                                                 transient.
                                                Hawaiian........................         182           0           0         822           0           0
Kogia spp.....................................  California......................      12,943          33           0      64,715         165           0
Long-beaked common dolphin....................  California......................      73,113           2           0     365,565          10           0
Longman's beaked whale........................  Hawaiian........................       3,666           0           0      17,296           0           0
Melon-headed whale............................  Hawaiian........................       1,511           0           0       6,733           0           0
Mesoplodon beaked whales \3\..................  California, Oregon, & Washington       1,994           0           0       9,970           0           0
Northern right whale dolphin..................  California, Oregon, & Washington      51,596           1           0     257,980           5           0
Pacific white-sided dolphin...................  California, Oregon, & Washington      38,467           1           0     192,335           5           0
Pantropical spotted dolphin...................  Hawaiian........................      10,887           0           0      48,429           0           0
Pygmy killer whale............................  Hawaiian........................         571           0           0       2,603           0           0
Pygmy sperm whale.............................  Hawaiian........................         229           0           0       1,093           0           0
Risso's dolphin...............................  California, Oregon, & Washington      86,564           1           0     432,820           5           0
                                                Hawaiian........................       1,085           0           0       4,887           0           0
Rough-toothed dolphin.........................  Hawaiian........................       5,131           0           0      22,765           0           0
Short-beaked common dolphin...................  California, Oregon, & Washington     999,282          70          *3   4,996,410         350         *15
Short-finned pilot whale......................  California, Oregon, & Washington         308           0           0       1,540           0           0
                                                Hawaiian........................       9,150           0           0      40,760           0           0
Spinner dolphin...............................  Hawaii Stock Complex............       2,576           0           0      11,060           0           0
Striped dolphin...............................  California, Oregon, & Washington       3,545           0           0      17,725           0           0
                                                Hawaiian........................       3,498           0           0      15,422           0           0
California sea lion...........................  U.S. Stock......................     126,961          25          *4     634,805         125         *20
Northern fur seal.............................  San Miguel Island...............      20,083           5           0     100,415          25           0
Harbor seal...................................  California......................       5,906          11           0      29,530          55           0
Northern elephant seal........................  California Breeding.............      22,516          22           0     112,580         110           0
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ These numbers constitute the total for an annual maximum year (a notional 12-month period when all annual and non-annual events could occur) in
  which a RIMPAC exercise and Civilian Port Defense events would occur in Hawaii and SOCAL.
\2\ These numbers constitute the summation over a 5-year period with annual events occurring five times and non-annual events occurring three times.
\3\ Mesoplodon spp. in SOCAL for the undifferentiated occurrence of five Mesoplodon species (M. carlhubbsi, M. ginkgodens, M. perrini, M. peruvianus, M.
  stejnegeri but does not include Blainville's beaked whale listed separately above.

[[Page 7029]]

 
* These mortalities are considered in Table 18 as an unspecified ``any small odontocete and pinniped species.''

    Testing Activities--Table 19 summarizes the Navy's take request for 
testing activities and Table 20 specifies the Navy's take request for 
testing activities by species from the modeling estimates.
    While the Navy does not anticipate any mortalities predicted for 
testing activities by the acoustic modeling would occur, the Navy 
requests annual authorization for take by mortality of up to 19 small 
odontocetes (i.e., dolphins) and pinnipeds to include any combination 
of such species with potential presence in the Study Area as part of 
testing activities using impulsive sources.
    The Navy does not anticipate vessel strikes of marine mammals would 
occur during testing activities in the Study Area in any given year. 
Most testing conducted in the Study Area that involves surface ships is 
conducted on Navy ships. Therefore, the vessel strike take request for 
training activities covers those activities. For the smaller number of 
testing activities not conducted in conjunction with fleet training, 
the Navy requests a smaller number of takes resulting incidental to 
vessel strike. However, in order to account for the accidental nature 
of vessel strikes to large whales in general, and potential risk from 
any vessel movement within the Study Area, the Navy is seeking take 
authorization in the event a Navy vessel strike does occur while 
conducting testing during the five year period of NMFS' final 
authorization as follows:
     The take by vessel strike during testing activities in any 
given year of no more than two large whales total of any combination of 
species including gray whale, fin whale, blue whale, humpback whale, 
Bryde's whale, sei whale, minke whale, or sperm whale. The two takes 
per year requested would be no more than one of any species of blue 
whale, fin whale, humpback whale, sei whale, or sperm whale in any 
given year.
     The take by vessel strike of no more than three large 
whales from testing activities over the course of the 5-year 
regulations.

                   Table 19--Summary of Annual and 5-Year Take Request for Testing Activities
----------------------------------------------------------------------------------------------------------------
                                                                             Testing activities
                                                          ------------------------------------------------------
           MMPA Category                    Source            Annual authorization        5-Year authorization
                                                                     sought                      sought
----------------------------------------------------------------------------------------------------------------
Mortality.........................  Impulse..............  19 mortalities applicable   95 mortalities applicable
                                                            to any small odontocete     to any small odontocete
                                                            or pinniped species.        or pinniped species over
                                                                                        five years.
                                    Vessel strike........  No more than 2 large whale  No more than 3 large
                                                            mortalities in any given    whale mortalities over
                                                            year.\1\                    five years.\1\
Level A...........................  Impulse and Non-       145--Species specific data  725--Species specific
                                     Impulse.               shown in Table 21.          data shown in Table 21.
Level B...........................  Impulse and Non-       238,880--Species specific   1,194,400--Species
                                     Impulse.               data shown in Table 21.     specific data shown in
                                                                                        Table 21.
----------------------------------------------------------------------------------------------------------------
\1\ Navy cannot quantifiably predict that the proposed takes from testing (a total of two in a given year or
  over the course of 5-years) will be of any particular species, and therefore seeks take authorization for any
  combination of large whale species (gray whale, fin whale, blue whale, humpback whale, Bryde's whale, sei
  whale, minke whale, or sperm whale), but of the two takes in any given year, no more than one of each species
  of blue whale, fin whale, humpback whale, sei whale, or sperm whale is requested.


        Table 20--Species-Specific Take Requests From Modeling Estimates of Impulsive and Non-Impulsive Source Effects for All Testing Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                               Annually                     Total over 5-year rule
                    Species                                   Stock              -----------------------------------------------------------------------
                                                                                    Level B     Level A    Mortality    Level B     Level A    Mortality
--------------------------------------------------------------------------------------------------------------------------------------------------------
Blue whale....................................  Eastern North Pacific...........         413           0           0       2,065           0           0
                                                Central North Pacific...........          15           0           0          75           0           0
Fin whale.....................................  California, Oregon, & Washington         202           0           0       1,010           0           0
                                                Hawaiian........................          23           0           0         115           0           0
Humpback whale................................  California, Oregon, & Washington         101           0           0         505           0           0
                                                Central North Pacific...........         820           0           0       4,100           0           0
Sei whale.....................................  Eastern North Pacific...........          21           0           0         105           0           0
                                                Hawaiian........................          30           0           0         150           0           0
Sperm whale...................................  California, Oregon, & Washington         146           0           0         730           0           0
                                                Hawaiian........................         117           0           0         585           0           0
Guadalupe fur seal............................  Mexico..........................         269           0           0       1,345           0           0
Hawaiian monk seal............................  Hawaiian........................         358           0           0       1,790           0           0
Bryde's whale.................................  Eastern Tropical Pacific........           5           0           0          25           0           0
                                                Hawaiian........................          13           0           0          65           0           0
Gray whale....................................  Eastern North Pacific...........       2,570           1           0      12,850           5           0
Minke whale...................................  California, Oregon, & Washington          49           0           0         245           0           0
                                                Hawaiian........................          30           0           0         150           0           0
Baird's beaked whale..........................  California, Oregon, & Washington       1,045           0           0       5,225           0           0
Blainville's beaked whale.....................  Hawaiian........................         960           0           0       4,800           0           0

[[Page 7030]]

 
Bottlenose dolphin............................  California coastal..............         769           0           0       3,845           0           0
                                                California, Oregon & Washington        2,407           0           0      12,035           0           0
                                                 offshore.
                                                Hawaii Stock Complex............         337           0           0       1,685           0           0
Cuvier's beaked whale.........................  California, Oregon, & Washington       2,319           0           0      11,595           0           0
                                                Hawaiian........................       4,549           0           0      22,745           0           0
Dwarf sperm whale.............................  Hawaiian........................       2,376          28           0      11,880         140           0
Dall's porpoise...............................  California, Oregon, & Washington       5,215          32           0      26,075         160           0
False killer whale............................  Hawaii Insular..................           4           0           0          20           0           0
                                                Hawaii Pelagic..................          37           0           0         185           0           0
False killer whale............................  Northwest Hawaiian Islands......          14           0           0          70           0           0
Fraser's dolphin..............................  Hawaiian........................          45           0           0         225           0           0
Killer whale..................................  Eastern North Pacific offshore/           53           0           0         265           0           0
                                                 transient.
                                                Hawaiian........................          14           0           0          70           0           0
Kogia spp.....................................  California......................       1,232           6           0       6,160          30           0
Long-beaked common dolphin....................  California......................      47,851           2           0     239,255          10           0
Longman's beaked whale........................  Hawaiian........................         436           0           0       2,180           0           0
Melon-headed whale............................  Hawaiian........................         124           0           0         620           0           0
Mesoplodon beaked whales \1\..................  California, Oregon, & Washington         345           0           0       1,725           0           0
Northern right whale dolphin..................  California, Oregon, & Washington       5,729           1           0      28,645           5           0
Pacific white-sided dolphin...................  California, Oregon, & Washington       4,924           1           0      24,620           5           0
Pantropical spotted dolphin...................  Hawaiian........................         685           2           0       3,425          10           0
Pygmy killer whale............................  Hawaiian........................          61           0           0         305           0           0
Pygmy sperm whale.............................  Hawaiian........................         117           1           0         585           5           0
Risso's dolphin...............................  California, Oregon, & Washington       8,739           1           0      43,695           5           0
                                                Hawaiian........................         113           0           0         565           0           0
Rough-toothed dolphin.........................  Hawaiian........................         410           0           0       2,050           0           0
Short-beaked common dolphin...................  California, Oregon, & Washington     122,748          40        * 13     613,740         200        * 65
Short-finned pilot whale......................  California, Oregon, & Washington          79           0           0         395           0           0
                                                Hawaiian........................         797           0           0       3,985           0           0
Spinner dolphin...............................  Hawaii Stock Complex............         167           1           0         835           5           0
Striped dolphin...............................  California, Oregon, & Washington         998           0           0       4,990           0           0
                                                Hawaiian........................         269           1           0       1,345           5           0
California sea lion...........................  U.S. Stock......................      13,038          17         * 6      65,190          85        * 30
Northern fur seal.............................  San Miguel Island...............       1,088           3           0       5,440          15           0
Harbor seal...................................  California......................         892           3           0       4,460          15           0
Northern elephant seal........................  California Breeding.............       2,712           5           0      13,560          25           0
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Mesoplodon spp. in SOCAL for the undifferentiated occurrence of five Mesoplodon species (M. carlhubbsi, M. ginkgodens, M. perrini, M. peruvianus, M.
  stejnegeri) but does not include Blainville's beaked whale listed separately above.
* These mortalities are considered in Table 20 as an unspecified ``any small odontocete and pinniped species.''

Marine Mammal Habitat

    The Navy's proposed training and testing activities could 
potentially affect marine mammal habitat through the introduction of 
sound into the water column, impacts to the prey species of marine 
mammals, bottom disturbance, or changes in water quality. Each of these 
components was considered in the HSTT DEIS/OEIS and was determined by 
the Navy to have no effect on marine mammal habitat. Based on the 
information below and the supporting information included in the HSTT 
DEIS/OEIS, NMFS has preliminarily determined that the proposed training 
and testing activities would not have adverse or long-term impacts on 
marine mammal habitat.

Important Marine Mammal Habitat

    The only ESA-listed marine mammal with designated critical habitat 
within the HSTT Study Area is the Hawaiian monk seal. Critical habitat 
was first established for the Hawaiian monk seal in 1986 to include all 
beach areas, sand spits and islets, lagoon waters, inner reef waters, 
and ocean waters to a depth of 18.3 m around specified northwestern 
Hawaiian Islands. These areas were expanded in 1988 and in 2011, NMFS 
proposed that six new extensive areas in the main Hawaiian Islands be 
added. However, specific areas were excluded from critical habitat 
designation because it was determined that the national security 
benefits of exclusion outweighed the benefits of inclusion, and that 
their exclusion would not result in extinction of the species. The 
excluded areas include: Kingfisher

[[Page 7031]]

Underwater Training area in marine areas off the northeast coast of 
Niihau; Pacific Missile Range Facility Main Base at Barking Sands, 
Kauai; Pacific Missile Range Facility Offshore Areas in marine areas 
off the western coast of Kauai; the Naval Defensive Sea Area and Puuloa 
Underwater Training Range in marine areas outside Pearl Harbor, Oahu; 
and the Shallow Water Minefield Sonar Training Range off the western 
coast of Kahoolawe in the Maui Nui area.
    The nearshore areas in and around the Hawaiian Humpback Whale 
National Marine Sanctuary contain very important breeding and calving 
habitat for the humpback whale; however, effects in this area have been 
analyzed previously in this document in the context of the whales 
themselves. There are no known specific breeding areas within the SOCAL 
Range Complex with the exception of pinnipeds. Much is unknown about 
the specifics of dolphin mating, but it is presumed that these species 
mate throughout their habitat and possibly throughout the year. Even 
less is known about the mating habits of beaked whales. Most of the 
offshore area within the SOCAL Range Complex could potentially be 
utilized for active sonar activities or underwater detonations. The 
Navy assumes that active sonar activities could take place within 
potential mating areas of these toothed whale species within SOCAL, 
although current state of knowledge is very limited and there may be 
seasonal components to distribution that could account for breeding 
activities outside of the SOCAL Range Complex. Baleen whales and sperm 
whales breed in deep tropical and subtropical waters south and west of 
the SOCAL Range Complex.

Expected Effects on Habitat

    Unless the sound source or explosive detonation is stationary and/
or continuous over a long duration in one area, the effects of the 
introduction of sound into the environment are generally considered to 
have a less severe impact on marine mammal habitat than the physical 
alteration of the habitat. Activities involving sound or energy from 
sonar and other active acoustic sources would not occur on shore in 
designated Hawaiian monk seal critical habitat where haul out and 
resting behavior occurs and would have no effect on critical habitat at 
sea. Acoustic exposures are not expected to result in long-term 
physical alteration of the water column or bottom topography, as the 
occurrences are of limited duration and are intermittent in time. 
Surface vessels associated with the activities are present in limited 
duration and are intermittent as they are continuously and relatively 
rapidly moving through any given area. Most of the high-explosive 
military expended materials would detonate at or near the water 
surface. Only bottom-laid explosives are likely to affect bottom 
substrate; habitat used for underwater detonations and seafloor device 
placement would primarily be soft-bottom sediment. Once on the 
seafloor, military expended material would likely be colonized by 
benthic organisms because the materials would serve as anchor points in 
the shifting bottom substrates, similar to a reef. The surface area of 
bottom substrate affected would make up a very small percentage of the 
total training area available in the HSTT Study Area.

Effects on Marine Mammal Prey

    Invertebrates--Marine invertebrate distribution in the HSTT Study 
Area is influenced by habitat, ocean currents, and water quality 
factors such as temperature, salinity, and nutrient content (Levinton 
2009). The distribution of invertebrates is also influenced by their 
distance from the equator (latitude); in general, the number of marine 
invertebrate species increases toward the equator (Macpherson 2002). 
The higher number of species (diversity) and abundance of marine 
invertebrates in coastal habitats, compared with the open ocean, is a 
result of more nutrient availability from terrestrial environments and 
the variety of habitats and substrates found in coastal waters 
(Levinton 2009).
    Marine invertebrates in the Hawaii Range Complex (HRC) portion of 
the HSTT Study Area inhabit coastal waters and seafloor habitats, 
including rocky intertidal zones, coral reefs, deep-water slopes, 
canyons, and seamounts. Corals are the primary living structural 
components of Hawaii's subtidal zone, with an average of about 20.3 
percent coral coverage in the main Hawaiian Islands (Friedlander et al. 
2005). Approximately 250 species of corals are found within the main 
Hawaiian Islands, but the area is dominated by six species (Maragos et 
al., 2004; Friedlander et al., 2005). The Northwestern Hawaiian Islands 
have at least 57 species of stony coral (Maragos et al. 2004). The 
coral reefs of the Northwestern Hawaiian Islands support diverse 
communities of bottom-dwelling invertebrates. Over 800 non-coral 
invertebrate species have been identified from the Northwestern 
Hawaiian Islands. Mollusks, echinoderms, and crustaceans dominate, 
representing 80 percent of the invertebrate species (Friedlander et al. 
2005).
    Marine invertebrates in the Southern California portion of the HSTT 
Study Area inhabit coastal waters and benthic habitats, including salt 
marshes, kelp forests, soft sediments, canyons, and the continental 
shelf. The diverse range of species include oysters, crabs, worms, 
ghost shrimp, California horn snails (Cerithidea californica), sponges, 
sea fans, isopods, and stony corals (Proctor et al., 1980; Dugan et 
al., 2000; Chess and Hobson, 1997). The Channel Islands, off the coast 
of Southern California, are situated in a transitional location between 
cold and warm water, making them host to over 5,000 invertebrate 
species (Tissot et al., 2006). Soft-bottom communities of California 
estuaries, such as San Diego Bay, are home to mostly crustaceans, 
marine worms, and mollusks (Navy and San Diego Unified Port District, 
2000).
    Very little is known about sound detection and use of sound by 
aquatic invertebrates (Budelmann 2010; Montgomery et al., 2006; Popper 
et al., 2001). Organisms may detect sound by sensing either the 
particle motion or pressure component of sound, or both. Aquatic 
invertebrates probably do not detect pressure since many are generally 
the same density as water and few, if any, have air cavities that would 
function like the fish swim bladder in responding to pressure 
(Budelmann 2010; Popper et al., 2001). Many marine invertebrates, 
however, have ciliated ``hair'' cells that may be sensitive to water 
movements, such as those caused by currents or water particle motion 
very close to a sound source (Budelmann 2010; Mackie and Singla 2003). 
These cilia may allow invertebrates to sense nearby prey or predators 
or help with local navigation. Marine invertebrates may produce and use 
sound in territorial behavior, to deter predators, to find a mate, and 
to pursue courtship (Popper et al., 2001).
    Both behavioral and auditory brainstem response studies suggest 
that crustaceans may sense sounds up to three kilohertz (kHz), but best 
sensitivity is likely below 200 Hz (Lovell et al., 2005; Lovell et al. 
2006; Goodall et al. 1990). Most cephalopods (e.g., octopus and squid) 
likely sense low-frequency sound below 1,000 Hz, with best 
sensitivities at lower frequencies (Budelmann 2010; Mooney et al., 
2010; Packard et al., 1990). A few cephalopods may sense higher 
frequencies up to 1,500 Hz (Hu et al., 2009). Squid did not respond to 
toothed whale ultrasonic echolocation clicks at sound pressure levels 
ranging from 199 to 226 dB re 1 [mu]Pa peak-to-peak, likely because 
these clicks were outside of squid hearing range (Wilson et al.,

[[Page 7032]]

2007). However, squid exhibited alarm responses when exposed to 
broadband sound from an approaching seismic airgun with received levels 
exceeding 145 to 150 dB re 1 [mu]Pa root mean square (McCauley et al., 
2000b).
    Little information is available on the potential impacts on marine 
invertebrates of exposure to sonar, explosions, and other sound-
producing activities. It is expected that most marine invertebrates 
would not sense mid- or high-frequency sounds, distant sounds, or 
aircraft noise transmitted through the air-water interface. Most marine 
invertebrates would not be close enough to intense sound sources, such 
as some sonars, to potentially experience impacts to sensory 
structures. Any marine invertebrate capable of sensing sound may alter 
its behavior if exposed to non-impulsive sound, although it is unknown 
if responses to non-impulsive sounds occur. Continuous noise, such as 
from vessels, may contribute to masking of relevant environmental 
sounds, such as reef noise. Because the distance over which most marine 
invertebrates are expected to detect any sounds is limited and vessels 
would be in transit, any sound exposures with the potential to cause 
masking or behavioral responses would be brief and long-term impacts 
are not expected. Although non-impulsive underwater sounds produced 
during training and testing activities may briefly impact individuals, 
intermittent exposures to non-impulsive sounds are not expected to 
impact survival, growth, recruitment, or reproduction of widespread 
marine invertebrate populations.
    Most detonations would occur greater than 3 nm from shore. As water 
depth increases away from shore, benthic invertebrates would be less 
likely to be impacted by detonations at or near the surface. In 
addition, detonations near the surface would release a portion of their 
explosive energy into the air, reducing the explosive impacts in the 
water. Some marine invertebrates may be sensitive to the low-frequency 
component of impulsive sound, and they may exhibit startle reactions or 
temporary changes in swim speed in response to an impulsive exposure. 
Because exposures are brief, limited in number, and spread over a large 
area, no long-term impacts due to startle reactions or short-term 
behavioral changes are expected. Although individual marine 
invertebrates may be injured or killed during an explosion or pile 
driving, no long-term impacts on the survival, growth, recruitment, or 
reproduction of marine invertebrate populations are expected.
    Fish--Fish are not distributed uniformly throughout the HSTT Study 
Area, but are closely associated with a variety of habitats. Some 
species range across thousands of square miles while others have small 
home ranges and restricted distributions (Helfman et al., 2009).
    Currently 566 species of reef and shore fishes are known to occur 
around the Insular Pacific-Hawaiian Large Marine Ecosystem within the 
HSTT Study Area. The high number of species that are found only in 
Hawaii can be explained by its geographical and hydrographical 
isolation (Randall 1998). Migratory open ocean fishes, such as the 
larger tunas, the billfishes, and some sharks, are able to move across 
the great distance that separates the Hawaiian Islands from other 
islands or continents in the Pacific. Coral reef fish communities in 
the Hawaiian Islands (excluding Nihoa) show a consistent pattern of 
species throughout the year. Exceptions include the seasonal 
distributions of migratory, open ocean species. Several reef fish 
species also show seasonal fluctuations which are usually related to 
movements of juveniles into new areas or spawning activity (U. S. Navy 
Office of Naval Research, 2001).
    The Southern California portion of the HSTT Study Area is in a 
region of highly productive fisheries (Leet et al., 2001) within the 
California Current Large Marine Ecosystem. The portion of the 
California Bight in the HSTT Study Area is a transitional zone between 
cold and warm water masses, geographically separated by Point 
Conception. The cold-water California Current Large Marine Ecosystem is 
rich in microscopic plankton (diatoms, krill, and other organisms), 
which form the base of the food chain in the Southern California 
portion of the HSTT Study Area. Small coastal pelagic fishes depend on 
this plankton and in turn are fed on by larger species (such as highly 
migratory species). The high fish diversity found in the HSTT Study 
Area occurs for several reasons: (1) The ranges of many temperate and 
tropical species extend into Southern California; (2) the area has 
complex bottom features and physical oceanographic features that 
include several water masses and a changeable marine climate (Allen et 
al. 2006; Horn and Allen 1978); and (3) the islands and coastal areas 
provide a diversity of habitats that include soft bottom, rocky reefs, 
kelp beds, and estuaries, bays, and lagoons.
    All fish have two sensory systems to detect sound in the water: the 
inner ear, which functions very much like the inner ear in other 
vertebrates, and the lateral line, which consists of a series of 
receptors along the fish's body (Popper 2008). The inner ear generally 
detects relatively higher-frequency sounds, while the lateral line 
detects water motion at low frequencies (below a few hundred Hz) 
(Hastings and Popper 2005a). Although hearing capability data only 
exist for fewer than 100 of the 32,000 fish species, current data 
suggest that most species of fish detect sounds from 50 to 1,000 Hz, 
with few fish hearing sounds above 4 kHz (Popper 2008). It is believed 
that most fish have their best hearing sensitivity from 100 to 400 Hz 
(Popper 2003b). Additionally, some clupeids (shad in the subfamily 
Alosinae) possess ultrasonic hearing (i.e., able to detect sounds above 
100,000 Hz) (Astrup 1999). Permanent hearing loss, or permanent 
threshold shift has not been documented in fish. The sensory hair cells 
of the inner ear in fish can regenerate after they are damaged, unlike 
in mammals where sensory hair cells loss is permanent (Lombarte et al. 
1993; Smith et al. 2006). As a consequence, any hearing loss in fish 
may be as temporary as the timeframe required to repair or replace the 
sensory cells that were damaged or destroyed (e.g., Smith et al. 2006).
    Potential direct injuries from non-impulsive sound sources, such as 
sonar, are unlikely because of the relatively lower peak pressures and 
slower rise times than potentially injurious sources such as 
explosives. Non-impulsive sources also lack the strong shock waves 
associated with an explosion. Therefore, direct injury is not likely to 
occur from exposure to non-impulsive sources such as sonar, vessel 
noise, or subsonic aircraft noise. Only a few fish species are able to 
detect high-frequency sonar and could have behavioral reactions or 
experience auditory masking during these activities. These effects are 
expected to be transient and long-term consequences for the population 
are not expected. MFAS is unlikely to impact fish species because most 
species are unable to detect sounds in this frequency range and vessels 
operating MFAS would be transiting an area (not stationary). While a 
large number of fish species may be able to detect low-frequency sonar 
and other active acoustic sources, low-frequency active usage is rare 
and mostly conducted in deeper waters. Overall effects to fish from 
would be localized and infrequent.
    Physical effects from pressure waves generated by underwater sounds 
(e.g. underwater explosions) could potentially affect fish within 
proximity of training or testing activities. In particular, the rapid 
oscillation between high- and low-pressure peaks has the

[[Page 7033]]

potential to burst the swim bladders and other gas-containing organs of 
fish (Keevin and Hemen 1997). Sublethal effects, such as changes in 
behavior of fish, have been observed in several occasions as a result 
of noise produced by explosives (National Research Council of the 
National Academies 2003; Wright 1982). If an individual fish were 
repeatedly exposed to sounds from underwater explosions that caused 
alterations in natural behavioral patterns or physiological stress, 
these impacts could lead to long-term consequences for the individual 
such as reduced survival, growth, or reproductive capacity. However, 
the time scale of individual explosions is very limited, and training 
exercises involving explosions are dispersed in space and time. 
Consequently, repeated exposure of individual fish to sounds from 
underwater explosions is not likely and most acoustic effects are 
expected to be short-term and localized. Long-term consequences for 
populations would not be expected. A limited number of fish may be 
killed in the immediate proximity of pile driving locations and 
additional fish may be injured. Short-term effects such as masking, 
stress, behavioral change, and hearing threshold shifts are also 
expected during pile driving operations. However, given the relatively 
small area that would be affected, and the abundance and distribution 
of the species concerned, no population-level effects are expected. The 
abundances of various fish and invertebrates near the detonation point 
of an explosion or around a pile driving location could be altered for 
a few hours before animals from surrounding areas repopulate the area; 
however these populations would be replenished as waters near the sound 
source are mixed with adjacent waters.

Marine Mammal Avoidance

    Marine mammals may be temporarily displaced from areas where Navy 
training and testing is occurring, but the area should be utilized 
again after the activities have ceased. Avoidance of an area can help 
the animal avoid further acoustic effects by avoiding or reducing 
further exposure. The intermittent or short duration of many activities 
should prevent animals from being exposed to stressors on a continuous 
basis. In areas of repeated and frequent acoustic disturbance, some 
animals may habituate or learn to tolerate the new baseline or 
fluctuations in noise level. 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.

Other Expected Effects

    Other sources that may affect marine mammal habitat were considered 
in the HSTT DEIS/OEIS and potentially include the introduction of fuel, 
debris, ordnance, and chemical residues into the water column. The 
majority of high-order explosions would occur at or above the surface 
of the ocean, and would have no impacts on sediments and minimal 
impacts on water quality. While disturbance or strike from an item 
falling through the water column is possible, it is unlikely because 
(1) Objects sink slowly, (2) most projectiles are fired at targets (and 
hit those targets), and (3) animals are generally widely dispersed 
throughout the water column and over the HSTT Study Area. Chemical, 
physical, or biological changes in sediment or water quality would not 
be detectable. In the event of an ordnance failure, the energetic 
materials it contained would remain mostly intact. The explosive 
materials in failed ordnance items and metal components from training 
and testing would leach slowly and would quickly disperse in the water 
column. Chemicals from other explosives would not be introduced into 
the water column in large amounts and all torpedoes would be recovered 
following training and testing activities, reducing the potential for 
chemical concentrations to reach levels that can affect sediment 
quality, water quality, or benthic habitats.

Analysis and Negligible Impact Determination

    Pursuant to NMFS' regulations implementing the MMPA, an applicant 
is required to estimate the number of animals that will be ``taken'' by 
the specified activities (i.e., takes by harassment only, or takes by 
harassment, injury, and/or death). This estimate informs the analysis 
that NMFS must perform to determine whether the activity will have a 
``negligible impact'' on the affected species or stock. Level B 
(behavioral) harassment occurs at the level of the individual(s) and 
does not assume any resulting population-level consequences, though 
there are known avenues through which behavioral disturbance of 
individuals can result in population-level effects (e.g., pink-footed 
geese (Anser brachyrhynchus) in undisturbed habitat gained body mass 
and had about a 46-percent reproductive success compared with geese in 
disturbed habitat (being consistently scared off the fields on which 
they were foraging) which did not gain mass and had a 17-percent 
reproductive success). 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 Level B 
harassment 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 behavioral 
harassment, NMFS must consider other factors, such as the likely nature 
of any responses (their intensity, duration, etc.), the context of any 
responses (critical reproductive time or location, migration, etc.), as 
well as the number and nature of estimated Level A harassment takes, 
the number of estimated mortalities, and effects on habitat. Generally 
speaking, and especially with other factors being equal, 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 throughout species, individuals, or circumstances) and 
less severe effects from takes resulting from exposure to lower 
received levels.
    The Navy's specified activities have been described based on best 
estimates of the maximum number of activity hours or detonations that 
the Navy would conduct. There may be some flexibility in the exact 
number of hours, items, or detonations may vary from year to year, but 
totals would not exceed the 5-year totals indicated in Tables 19 and 
21. Furthermore the Navy's take request is based on their model and 
post-model analysis. The requested number of Level B 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) 
that will occur. Depending on the location, duration, and frequency of 
activities, along with the distribution and movement of marine mammals, 
individual animals may be exposed multiple times to impulse or non-
impulse sounds at or above the Level B harassment threshold. However, 
the Navy is currently unable to estimate the number of individuals that 
may be taken during training and testing activities. The model results 
over estimate the overall number of takes that may occur to a smaller 
number of individuals. While the model shows that an increased number 
of exposures may take place (compared to the 2009 rulemakings for HRC 
and the SOCAL Range Complex), the types and severity of individual 
responses to training and testing activities are not expected to 
change.

[[Page 7034]]

    Taking the above into account, considering the sections discussed 
below, and dependent upon the implementation of the proposed mitigation 
measures, NMFS has preliminarily determined that Navy's proposed 
training and testing exercises would have a negligible impact on the 
marine mammal species and stocks present in the Study Area.

Behavioral Harassment

    As discussed previously in this document, marine mammals can 
respond to MFAS/HFAS in many different ways, a subset of which 
qualifies as harassment (see Behavioral Harassment Section). One thing 
that the take estimates do not take into account is the fact that most 
marine mammals will likely avoid strong sound sources to one extent or 
another. Although an animal that avoids the sound source will likely 
still be taken in some instances (such as if the avoidance results in a 
missed opportunity to feed, interruption of reproductive behaviors, 
etc.) in other cases avoidance may result in fewer instances of take 
than were estimated or in the takes resulting from exposure to a lower 
received level than was estimated, which could result in a less severe 
response. For MFAS/HFAS, the Navy provided information (Table 21) 
estimating the percentage of behavioral harassment that would occur 
within the 6-dB bins (without considering mitigation or avoidance). As 
mentioned above, an animal's exposure to a higher received level is 
more likely to result in a behavioral response that is more likely to 
adversely affect the health of the animal. As the table illustrates, 
the vast majority (about 83 percent, at least for hull-mounted sonar, 
which is responsible for most of the sonar takes) of calculated takes 
for MFAS result from exposures between 156 dB and 162 dB. Less than 0.5 
percent of the takes are expected to result from exposures above 174 
dB.

                                                      Table 21--Non-Impulsive Ranges in 6-dB Bins and Ppercentage of Behavioral Harassments
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                   Sonar bin MF1 (e.g., SQS-53; ASW hull     Sonar bin MF4 (e.g., AQS-22; ASW        Sonar Bin MF5 (e.g., SSQ-62; ASW        Sonar Bin HF4 (e.g., SQQ-32; MIW
                                              mounted sonar)                          dipping sonar)                             sonobuoy)                                sonar)
                                 ---------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Percentage of                           Percentage of                           Percentage of                           Percentage of
         Received level            Distance at which      behavioral       Distance at which      behavioral       Distance at which      behavioral       Distance at which      behavioral
                                     levels occur         harassments        levels occur         harassments        levels occur         harassments        levels occur         harassments
                                   within radius of   occurring at given   within radius of   occurring at given   within radius of   occurring at given   within radius of   occurring at given
                                      source (m)            levels            source (m)            levels            source (m)            levels            source (m)            levels
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                     Low Frequency Cetaceans
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
120 <=SPL <126..................  172,558-162,925...  0.00..............  40,000-40,000.....  0.00..............  23,880-17,330.....  0.00..............  3,100-2,683.......  0.00
126 <=SPL <132..................  162,925-117,783...  0.00..............  40,000-40,000.....  0.00..............  17,330-12,255.....  0.10..............  2,683-2,150.......  0.01
132 <=SPL <138..................  117,783-108,733...  0.04..............  40,000-12,975.....  3.03..............  12,255-7,072......  4.12..............  2,150-1,600.......  0.48
138 <=SPL <144..................  108,733-77,850....  1.57..............  12,975-12,800.....  0.14..............  7,072-3,297.......  23.69.............  1,600-1,150.......  4.20
144 <=SPL <150..................  77,850-58,400.....  5.32..............  12,800-6,525......  27.86.............  3,297-1,113.......  42.90.............  1,150-575.........  24.79
150 <=SPL <156..................  58,400-53,942.....  4.70..............  6,525-2,875.......  36.83.............  1,113-255.........  24.45.............  575-300...........  28.10
156 <=SPL <162..................  53,942-8,733......  83.14.............  2,875-1,088.......  23.78.............  255-105...........  3.52..............  300-150...........  24.66
162 <=SPL <168..................  8,733-4,308.......  3.51..............  1,088-205.........  7.94..............  105-55............  1.08..............  150-100...........  9.46
168 <=SPL <174..................  4,308-1,950.......  1.31..............  205-105...........  0.32..............  55-55.............  0.00..............  100-<50...........  8.30
174 <=SPL <180..................  1,950-850.........  0.33..............  105-55............  0.10..............  55-55.............  0.00..............  <50...............  0.00
180 <=SPL <186..................  850-400...........  0.06..............  55-<50............  0.01..............  55-<50............  0.13..............  <50...............  0.00
186 <=SPL <192..................  400-200...........  0.01..............  <50...............  0.00..............  <50...............  0.00..............  <50...............  0.00
192 <= SPL <198.................  200-100...........  0.00..............  <50...............  0.00..............  <50...............  0.00..............  <50...............  0.00
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                     Mid-Frequency Cetaceans
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
120 <= SPL <126.................  172,592-162,933...  0.00..............  40,000-40,000.....  0.00..............  24,205-18,872.....  0.00..............  4,133-3,600.......  0.00
126 <= SPL <132.................  162,933-124,867...  0.00..............  40,000-40,000.....  0.00..............  18,872-12,697.....  0.10..............  3,600-3,075.......  0.00
132 <= SPL <138.................  124,867-108,742...  0.07..............  40,000-12,975.....  2.88..............  12,697-7,605......  3.03..............  3,075-2,525.......  0.01
138 <= SPL <144.................  108,742-78,433....  1.54..............  12,975-12,800.....  0.02..............  7,605-4,080.......  17.79.............  2,525-1,988.......  0.33
144 <= SPL <150.................  78,433-58,650.....  5.41..............  12,800-6,525......  26.73.............  4,080-1,383.......  46.83.............  1,988-1,500.......  2.83
150 <= SPL <156.................  58,650-53,950.....  4.94..............  6,525-2,875.......  36.71.............  1,383-300.........  27.08.............  1,500-1,000.......  14.92
156 <= SPL <162.................  53,950-8,925......  82.62.............  2,875-1,088.......  25.65.............  300-155...........  3.06..............  1,000-500.........  40.11
162 <= SPL <168.................  8,925-4,375.......  3.66..............  1,088-205.........  7.39..............  155-55............  2.02..............  500-300...........  22.18
168 <= SPL <174.................  4,375-1,992.......  1.34..............  205-105...........  0.52..............  55-55.............  0.00..............  300-150...........  14.55
174 <= SPL <180.................  1,992-858.........  0.34..............  105-55............  0.09..............  55-55.............  0.00..............  150-<50...........  5.07
180 <= SPL <186.................  858-408...........  0.06..............  55-<50............  0.01..............  55-<50............  0.09..............  <50...............  0.00
186 <= SPL <192.................  408-200...........  0.01..............  <50...............  0.00..............  <50...............  0.00..............  <50...............  0.00
192 <= SPL <198.................  200-100...........  0.00..............  <50...............  0.00..............  <50...............  0.00..............  <50...............  0.00
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
ASW: anti-submarine warfare; MIW: mine warfare; m: meter; SPL: sound pressure level

    Although the Navy has been monitoring to discern the effects of 
MFAS/HFAS on marine mammals since 2006, and research on the effects of 
MFAS is advancing, our understanding of exactly how marine mammals in 
the Study Area will respond to MFAS/HFAS is still limited. The Navy has 
submitted reports from more than 60 major exercises conducted in the 
HRC and SOCAL, and off the Atlantic Coast, that indicate no behavioral 
disturbance was observed. One cannot conclude from these results that 
marine mammals were not harassed from MFAS/HFAS, as a portion of 
animals within the area of concern were not seen (especially those more 
cryptic, deep-diving species, such as beaked whales or Kogia spp.), the 
full series of behaviors that would more accurately show an important 
change is not typically seen (i.e., only the surface behaviors are 
observed), and some of the non-biologist watchstanders might not be 
well-qualified to characterize behaviors. However, one can say that the 
animals that were observed did not respond in any of the obviously more 
severe ways, such as panic, aggression, or anti-predator response.

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

[[Page 7035]]

more than one diel cycle or recur on subsequent days (Southall et al., 
2007). 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).
    In the previous section, we discussed that potential behavioral 
responses to MFAS/HFAS that fall into the category of harassment could 
range in severity. By definition, for military readiness activities, 
takes by behavioral harassment involve the disturbance or likely 
disturbance of a marine mammal or marine mammal stock in the wild by 
causing disruption of natural behavioral patterns (such as migration, 
surfacing, nursing, breeding, feeding, or sheltering) to a point where 
such behavioral patterns are abandoned or significantly altered. These 
reactions would, however, be more of a concern if they were expected to 
last over 24 hrs or be repeated in subsequent days. However, vessels 
with hull-mounted active sonar are typically moving at speeds of 10-15 
knots, 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. Animals may be exposed to MFAS/HFAS for more than one day or 
on successive days. However, because neither the vessels nor the 
animals are stationary, significant long-term effects are not expected.
    Most planned explosive exercises are of a short duration (1-6 
hours). 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. TTS
    As mentioned previously, 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. 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 [frac12] 
octave above). The more powerful MF sources used have center 
frequencies between 3.5 and 8 kHz and the other unidentified MF sources 
are, by definition, less than 10 kHz, which suggests that TTS induced 
by any of these MF sources would be in a frequency band somewhere 
between approximately 2 and 20 kHz. 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 20 and 100 
kHz, which means that TTS could range up to 200 kHz; 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 
even less likely). TTS from explosives would be broadband. Vocalization 
data for each species was provided in the Navy's LOA application.
    2. Degree of the shift (i.e., how many dB is the sensitivity of the 
hearing reduced by)--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 document. 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 knots). In the TTS studies, 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, MFAS emits a 
nominal ping every 50 seconds, and incurring those levels of TTS is 
highly unlikely.
    3. Duration of TTS (recovery time)--In the TTS laboratory studies, 
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), though 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 MFAS/HFAS training exercises in the 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 days (and any 
incident of TTS would likely be far less severe due to the short 
duration of the majority of the exercises and the speed of a typical 
vessel). Also, for the same reasons discussed in the 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. If impaired, marine mammals would typically be aware of 
their impairment and implement behaviors to compensate (see Acoustic 
Masking or Communication Impairment section), though these 
compensations may incur energetic costs.

Acoustic Masking or Communication Impairment

    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. Standard MFAS nominally pings every 
50 seconds for hull-mounted sources. For the sources for which we know 
the pulse length, most are significantly shorter than hull-mounted 
active sonar, on the order of several microseconds to tens of 
microseconds. For hull-mounted active sonar, though some of the 
vocalizations that marine mammals make are less than one second long, 
there is only a 1 in 50 chance that they would occur exactly when the 
ping was received, and when vocalizations are longer than one second, 
only parts of them are masked. Alternately, when the pulses are only 
several microseconds long, the majority of most animals' vocalizations 
would not be masked. Masking effects from MFAS/HFAS are expected to be 
minimal. If masking or communication impairment were to occur briefly, 
it would be in the frequency range of MFAS, which overlaps with some 
marine mammal vocalizations; however, it would likely not mask the 
entirety of any particular vocalization or communication series because 
the signal length, frequency, and duty cycle of the MFAS/HFAS signal 
does not perfectly mimic the characteristics of any marine mammal's 
vocalizations.

[[Page 7036]]

PTS, Injury, or Mortality

    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 vessel at a close distance, NMFS believes 
that the mitigation measures (i.e., shutdown/powerdown zones for MFAS/
HFAS) 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 
all ASW exercises) in addition to watchstanders on vessels to detect 
marine mammals for mitigation implementation.
    If a marine mammal is able to approach a surface vessel within the 
distance necessary to incur PTS, the likely speed of the vessel 
(nominal 10-15 knots) 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 and 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, and many animals are 
able to compensate for the shift, although it may include energetic 
costs.
    As discussed previously, marine mammals (especially beaked whales) 
could potentially respond to MFAS at a received level lower than the 
injury threshold in a manner that indirectly results in the animals 
stranding. The exact mechanism of this potential response, behavioral 
or physiological, is not known. When naval exercises have been 
associated with strandings in the past, it has typically been when 
three or more vessels are operating simultaneously, in the presence of 
a strong surface duct, and in areas of constricted channels, semi-
enclosed areas, and/or steep bathymetry. Based on the number of 
occurrences where strandings have been definitively associated with 
military active sonar versus the number of hours of active sonar 
training that have been conducted, we believe that the probability is 
small that this will occur. Lastly, an active sonar shutdown protocol 
for strandings involving live animals milling in the water minimizes 
the chances that these types of events turn into mortalities.
    While NMFS does not expect any mortalities from impulsive sources 
to occur, we are proposing to authorize takes by mortality of a limited 
number of small odontocetes and pinnipeds from training and testing 
activities. Based on previous vessel strikes in the Study Area, NMFS is 
also proposing to authorize takes by mortality of a limited number of 
large whales from vessel strike. As described previously, although we 
have a good sense of how many marine mammals the Navy may strike over 
the course of 5 years (and it is much smaller than the 15 large whale 
mortalities requested for all training and testing activities), the 
species distribution is unpredictable. Thus, we have analyzed the 
possibility that all large whale takes requested in one year may be of 
the same species. However, the number of takes authorized of a single 
species is limited (for example, no more than three takes of any one of 
the following species may occur in a single year: blue whale, fin 
whale, humpback whale, sei whale, and sperm whale). Over the first 
three years of the existing HRC and SOCAL rules, five mortalities have 
resulted from activities that would be covered by the HSTT rule: two 
mortalities from ship strike, and three confirmed mortalities from 
explosive exercises (which occurred before the monitoring was modified 
to its current form, which better protects animals when time-delay 
firing devices are used). The number of mortalities from vessel strikes 
are not expected to be an increase over the past decade, but rather 
they are being addressed under the incidental take authorization for 
the first time.

Species-Specific Analysis

    In the discussions below, the ``acoustic analysis'' refers to the 
Navy's model results and post-model analysis. The Navy performed a 
quantitative analysis to estimate the number of marine mammals that 
could be harassed by acoustic sources or explosives used during Navy 
training and testing activities. Inputs to the quantitative analysis 
included marine mammal density estimates; marine mammal depth 
occurrence distributions; oceanographic and environmental data; marine 
mammal hearing data; and criteria and thresholds for levels of 
potential effects. Marine mammal densities used in the model may 
overestimate actual densities when species data is limited and for 
species with seasonal migrations (e.g., humpbacks, blue whales, 
Hawaiian stock of fin whales, sei whales, gray whales). The 
quantitative analysis consists of computer modeled estimates and a 
post-model analysis to determine the number of potential mortalities 
and harassments. The model calculates sound energy propagation from 
sonars, 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 received by a marine mammal 
exceeds the thresholds for effects. The model estimates are then 
further analyzed to consider animal avoidance and implementation of 
mitigation measures, resulting in final estimates of effects due to 
Navy training and testing. It is important to note that the Navy's take 
estimates represent the total number of takes and not the number of 
individuals taken, as a single individual may be taken multiple times 
over the course of a year.
    Although this more complex computer modeling approach accounts for 
various environmental factors affecting acoustic propagation, the 
current software tools do not consider the likelihood that a marine 
mammal would attempt to avoid repeated exposures to a sound or avoid an 
area of intense activity where a training or testing event may be 
focused. Additionally, the software tools do not consider the 
implementation of mitigation (e.g., stopping sonar transmissions when a 
marine mammal is within a certain distance of a ship or range clearance 
prior to detonations). In both of these situations, naval activities 
are modeled as though an activity would occur regardless of proximity 
to marine mammals and without any horizontal movement by the animal 
away from the sound source or human activities (e.g., without 
accounting for likely animal avoidance). The initial model results 
overestimate the number of takes (as described previously), primarily 
by behavioral disturbance. 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. NMFS provided input to the Navy on this process and 
the Navy's qualitative analysis is described in detail in section 6.3 
of their LOA application (http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications).
    Mysticetes--The Navy's acoustic analysis indicates that numerous 
exposures of mysticete species to sound levels likely to result in 
Level B harassment may occur, mostly from sonar and other active 
acoustic stressors associated with mostly training and

[[Page 7037]]

some testing activities in the HSTT Study Area. Of these species, 
humpback, blue, fin, and sei whales are listed as endangered under the 
ESA. Level B takes are anticipated to be in the form of behavioral 
harassment and no injurious takes of humpback, blue, fin, or sei whales 
from sonar, or other active acoustic stressors are expected. The 
majority of acoustic effects to mysticetes from sonar and other active 
sound sources during training activities would be primarily from anti-
submarine warfare events involving surface ships and hull mounted (mid-
frequency) sonar. Most Level B harassments to mysticetes from sonar 
would result from received levels between 144 and 162 SPL. High-
frequency systems are not within mysticetes' ideal hearing range and it 
is unlikely that they would cause a significant behavioral reaction. 
The only mysticete species that may be exposed to sound or energy from 
explosions resulting in the possibility of PTS is the gray whale. 
Exposures would occur in the SOCAL Range Complex during the cool season 
However, the Navy's proposed mitigation zones for explosive activities 
extend beyond the predicted maximum range to PTS. The implementation of 
mitigation and the sightability of mysticetes (due to their large size) 
reduces the potential for a significant behavioral reaction or a 
threshold shift to occur. Furthermore, gray whales in particular should 
be easier to sight because they would be migrating through the HSTT 
Study Area and there is often more than one whale in an area at the 
same time.
    In addition to Level B takes, the Navy is requesting no more than 
12 large whale mortalities over 5 years (no more than 4 large whale 
mortalities in a given year) due to vessel strike during training 
activities and no more than three large whale mortalities over 5 years 
(no more than 2 large whale mortalities in any given year) due to 
vessel strike during testing activities. However, no more than three 
mortalities of any of the following species would be authorized to 
occur in a given year: blue whale, fin whale, humpback whale, sei 
whale, and sperm whale. The Navy provided a detailed analysis of strike 
data in section 6.3.4 of their LOA application. Marine mammal 
mortalities were not previously analyzed by NMFS in the 2009 
rulemakings for HRC and the SOCAL Range Complex. However, over a period 
of 20 years (1991 to 2010), there have been 16 Navy vessel strikes in 
the SOCAL Range Complex and five Navy vessel strikes in HRC. No single 
5-year period exceeded ten whales struck within SOCAL and HRC. The 
number of mortalities from vessel strike are not expected to be an 
increase over the past decade, but rather NMFS is proposing to 
authorize these takes for the first time.
    Areas of high humpback whale density in the HRC were discussed 
earlier in this document. Since humpback whales migrate to the north in 
the summer, impacts are predicted only for the cool season in the HSTT 
Study Area. While the humpback breeding areas around Hawaii are 
important, NMFS has determined that MFAS training in these areas is 
rare and infrequent and should not affect annual rates of recruitment 
or survival. As discussed in the Proposed Mitigation section of this 
document, the Navy has agreed that training exercises in the designated 
Humpback Whale Cautionary Area would require a much higher level of 
clearance than is normal practice in planning and conducting MFAS 
training. Furthermore, no reported cases of harmful effects to humpback 
whales attributed to MFAS use have occurred during the Navy's 40-plus 
years of training in the waters off the Hawaiian Islands. Coincident 
with this use of MFAS, abundance estimates reflect an annual increase 
in the humpback whale stock (Mobley 2001a, 2004). A recent long-term 
study of humpback whales in Hawaiian waters shows long-term fidelity to 
the Hawaiian winter grounds, with many showing sighting spans ranging 
from 10 to 32 years (Herman et al., 2011). The overall abundance of 
humpback whales in the north Pacific has continued to increase and is 
now greater than some pre-whaling abundance estimates (Barlow et al., 
2011). The California, Oregon, Washington stock of humpback whales use 
the waters within the Southern California portion of the HSTT Study 
Area as a summer feeding ground. No areas of specific importance for 
reproduction or feeding for other mysticetes have been identified in 
the HSTT Study Area.
    Sperm Whales--The Navy's acoustic analysis indicates that 3,595 
exposures of sperm whales to sound levels likely to result in Level B 
harassment may occur in the HSTT Study Area from sonar or other active 
acoustic stressors during training and testing activities. These Level 
B takes are anticipated to be in the form of behavioral harassment and 
no injurious takes of sperm whales from sonar, other active acoustic 
stressors, or explosives are requested or proposed for authorization. 
Sperm whales have shown resilience to acoustic and human disturbance, 
although they may react to sound sources and activities within a few 
kilometers. Sperm whales that are exposed to activities that involve 
the use of sonar and other active acoustic sources may alert, ignore 
the stimulus, avoid the area by swimming away or diving, or display 
aggressive behavior. Some (but not all) sperm whale vocalizations might 
overlap with the MFAS/HFAS TTS frequency range, which could temporarily 
decrease an animal's sensitivity to the calls of conspecifics or 
returning echolocation signals. However, as noted previously, NMFS does 
not anticipate TTS of a long duration or severe degree to occur as a 
result of exposure to MFAS/HFAS. The majority of Level B takes are 
expected to be in the form of mild responses. No areas of specific 
importance for reproduction or feeding for sperm whales have been 
identified in the HSTT Study Area.
    Pygmy and Dwarf Sperm Whales--The Navy's acoustic analysis 
indicates that 25,081 exposures of pygmy and dwarf sperm whales to 
sound levels likely to result in Level B harassment may occur from 
sonar and other active acoustic stressors and explosives associated 
with training and testing activities in the HRC. In SOCAL, the two 
Kogia species are managed as a single stock and management unit and up 
to 14,175 exposures to sound levels likely to result in Level B 
harassment may occur from sonar and other active acoustic stressors and 
explosives associated with training and testing activities. The Navy's 
acoustic analysis also indicates that 74 exposures of dwarf sperm whale 
and one exposure of pygmy sperm whale to sound levels likely to result 
in Level A harassment may occur from active acoustic stressors and 
explosions in HRC and 39 exposures of Kogia to sound levels likely to 
result in Level A harassment may occur from active acoustic stressors 
or explosions in SOCAL. Behavioral responses can range from a mild 
orienting response, or a shifting of attention, to flight and panic. 
These species tend to avoid human activity and presumably anthropogenic 
sounds. Pygmy and dwarm sperm whales may startle and leave the 
immediate area of activity, reducing the potential impacts. Significant 
behavioral reactions seem more likely than with most other odontocetes; 
however, it is unlikely that animals would receive multiple exposures 
over a short period of time, allowing animals to recover lost resources 
(e.g., food) or opportunities (e.g., mating). Therefore, long-term 
consequences for individual Kogia or their respective populations are 
not expected. Furthermore, many explosions actually occur upon impact

[[Page 7038]]

with above-water targets. However, sources such as these were modeled 
as exploding at 1 meter depth, which overestimates the potential 
effects.
    Data from several sources, which are summarized and cited on NOAA's 
Cetacean and Sound Mapping Web site (cetsound.noaa.gov) indicate that 
there are resident populations of dwarf sperm whales (among other 
species) off the western side of the Big Island of Hawaii. As discussed 
earlier, we highlight the presence of resident populations in the 
interest of helping to support decisions that ensure that these small 
populations, limited to a small area of preferred habitat, are not 
exposed to concentrations of activities within their ranges that have 
the potential to impact a large portion of the stock/species over 
longer amounts of time that could have detrimental consequences to the 
stock/species. However, NMFS has reviewed the Navy's exercise reports 
and considered/discussed their historical level of activity in the area 
where these resident populations are concentrated, which is very low, 
and concluded that time/area restrictions would not afford much 
reduction of impacts in this location and are not necessary at this 
point. If future monitoring and exercise reports suggest that increased 
operations are overlapping with these resident populations, NMFS would 
revisit the consideration of time/area limitations around these 
populations.
    Dall's Porpoise--The Navy's acoustic analysis indicates that 42,106 
exposures of Dall's porpoise to sound levels likely to result in Level 
B Harassment may occur from sonar and other active acoustic stressors 
and explosives associated with training and testing activities in the 
SOCAL Range Complex. The analysis also indicates that 79 exposures to 
sound levels likely to result in Level A Harassment may occur from 
sonar and other active acoustic stressors.
    Predicted impacts to odontocetes from activities from sonar and 
other active acoustic sources are mostly from anti-submarine warfare 
events involving surface ships and hull mounted sonar. For high-
frequency cetaceans, such as Dall's porpoise, ranges to TTS for 
multiple pings can, under certain conditions, reach over 10 km from a 
source. Activities involving ASW training often involve multiple 
participants and activities associated with the event. Sensitive 
species, such as Dall's porpoise, may avoid the area for the duration 
of the event and then return, allowing the animal to recover from any 
energy expenditure or missed resources. However, the Navy's proposed 
mitigation has a provision that allows the Navy to continue operation 
of MFAS if the animals are clearly bow-riding even after the Navy has 
initially maneuvered to try and avoid closing with the animals. Since 
these animals sometimes bow-ride, they could potentially be exposed to 
levels associated with TTS. Some dolphin vocalizations might overlap 
with the MFAS/HFAS TTS frequency range (2-20 kHz), which could 
potentially temporarily decrease an animal's sensitivity to the calls 
of conspecifics or returning echolocation signals. However, for the 
reasons described in the beginning of this section, NMFS does not 
anticipate TTS of a long duration or severe degree to occur as a result 
of exposure to MFA/HFAS.
    Ranges to PTS are on average about 855 meters from the largest 
explosive (Bin E12) for a high-frequency cetacean such as Dall's 
porpoise, which is less than the proposed mitigation zone for most 
explosive source bins. The metrics used to estimate PTS are based on 
the animal's mass; the smaller an animal, the more susceptible that 
individual is to these effects. In the Navy's analysis, all individuals 
of a given species were assigned the weight of that species' newborn 
calf. Since many individual Dall's porpoise are obviously larger than a 
newborn calf, this assumption causes the acoustic model to overestimate 
the potential effects. Threshold shifts do not necessarily affect all 
hearing frequencies equally, so some threshold shifts may not interfere 
with an animal hearing biologically relevant sounds.
    Odontocetes, such as Dall's porpoise, may further minimize sound 
exposure during avoidance due to directional hearing. No areas of 
specific importance for reproduction or feeding for Dall's porpoise 
have been identified in the HSTT Study Area.
    Beaked Whales--The Navy's acoustic analysis indicates that numerous 
exposures of beaked whale species to sound levels likely to result in 
Level B Harassment may occur from sonar and other active acoustic 
stressors associated with training and testing activities. 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 (McCarthy et 
al., 2011). Furthermore, in research done at the Navy's instrumented 
tracking range in the Bahamas, animals leave the immediate area of the 
anti-submarine warfare training exercise, but return within a few days 
after the event ends. At the Bahamas range and at Navy instrumented 
ranges in the HSTT Study Area that have been operating for decades (in 
Hawaii north of Kauai and in SOCAL west of San Clemente Island), 
populations of beaked whales appear to be stable. The analysis also 
indicates that no exposures to sound levels likely to result in Level A 
Harassment would occur. However, while the Navy's model did not 
quantitatively predict any mortalities of beaked whales, the Navy is 
requesting a limited number of takes by mortality given the 
sensitivities these species may have to anthropogenic activities. 
Almost 40 years of conducting similar exercises in the HSTT Study Area 
without observed incident indicates that injury or mortality are not 
expected to occur as a result of Navy activities.
    Some beaked whale vocalizations might overlap with the MFAS/HFAS 
TTS frequency range (2-20 kHz), which could potentially temporarily 
decrease an animal's sensitivity to the calls of conspecifics or 
returning echolocation signals. However, NMFS does not anticipate TTS 
of a long duration or severe degree to occur as a result of exposure to 
MFA/HFAS. No beaked whales are predicted to be exposed to MFAS/HFAS 
sound levels associated with PTS or injury. No areas of specific 
importance for reproduction or feeding for beaked whales have been 
identified in the HSTT Study Area.
    As discussed previously, scientific uncertainty exists regarding 
the potential contributing causes of beaked whale strandings and the 
exact behavioral or physiological mechanisms that can potentially lead 
to the ultimate physical effects (stranding and/or death) that have 
been documented in a few cases. Although NMFS does not expect injury or 
mortality of any of these species to occur as a result of the MFAS/HFAS 
training exercises, there remains the potential for the operation of 
MFAS to contribute to the mortality of beaked whales. Consequently, 
NMFS intends to authorize mortality and we consider the 10 potential 
mortalities from across the seven species potentially effected over the 
course of 5 years in our negligible impact determination (NMFS only 
intends to authorize a total of 10 beaked whale mortality takes, but 
since they could be of any of the species, we consider the effects of 
10 mortalities of any of the seven species).
    False Killer Whale--The Navy's acoustic analysis indicates that 761 
exposures of false killer whales (53 exposures to the Hawaii insular 
stock) to sound levels likely to result in Level B harassment may occur 
from sonar or other active acoustic stressors associated with training 
and testing activities in the HRC. False killer whales are not

[[Page 7039]]

expected to be present within the SOCAL Range Complex. These takes are 
anticipated to be in the form of behavioral harassment and no injurious 
takes of false killer whales from active acoustic stressors or 
explosives are requested or proposed for authorization. Behavioral 
responses can range from a mild orienting response, or a shifting of 
attention, to flight and panic.
    No areas of specific importance for reproduction or feeding for 
false killer whales have been identified in the HSTT Study Area.
    Short-beaked Common Dolphin--The Navy's acoustic analysis indicates 
that 1,122,030 exposures of short-beaked common dolphins to sound 
levels likely to result in Level B Harassment may occur from sonar and 
other active acoustic stressors associated with training and testing 
activities and sound or energy from explosions. Analysis also indicates 
that 110 exposures to sound levels likely to result in Level A 
Harassment may occur from active acoustic stressors and sound or energy 
from explosions. Up to 16 short-beaked common dolphin mortalities are 
also requested as part of an unspecified ``any small odontocete and 
pinniped species'' take. Short-beaked common dolphins are one of the 
most abundant dolphin species in SOCAL. Behavioral responses can range 
from alerting, to changing their behavior or vocalizations, to avoiding 
the sound source by swimming away or diving. The high take numbers are 
due in part to an increase in expended materials. However, this species 
generally travels in large pods and should be visible from a distance 
in order to implement mitigation measures and reduce potential impacts.
    No areas of specific importance for reproduction or feeding for 
short-beaked common dolphins have been identified in the HSTT Study 
Area.
    California Sea Lion--The Navy's acoustic analysis indicates that 
139,999 exposures of California sea lions to sound levels likely to 
result in Level B harassment may occur from sonar and other active 
acoustic stressors associated with training and testing activities and 
sound or energy from explosions. Analysis also indicates that 42 
exposures to sound levels likely to result in Level A Harassment may 
occur from active acoustic stressors and sound or energy from 
explosions. Up to 10 California sea lion mortalities are also requested 
as part of an unspecified ``any small odontocete and pinniped species'' 
take. California sea lions are the most abundant pinniped species along 
the California coast. Research and observations show that pinnipeds in 
the water are tolerant of anthropogenic noise and activity. California 
sea lions 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 behavior, or avoid the immediate area by swimming away or 
diving. Significant behavioral reactions are not expected, based on 
previous observations. The high take numbers are due in part to the 
explosive criteria being based on newborn calf weights. Assuming that 
the majority of the population is larger than a newborn calf, the model 
overestimates the effects to California sea lions. The criteria for 
slight lung injury are also very conservative and may overpredict the 
effects. Research and observations show that pinnipeds in the water are 
tolerant of anthropogenic noise and activity. 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 exposure.
    Northern Fur Seal--The Navy's acoustic analysis indicates that 
21,171 exposures of northern fur seals to sound levels likely to result 
in Level B Harassment may occur from sonar and other active acoustic 
stressors associated with training and testing activities in the SOCAL 
Range Complex and sound or energy from explosions. Analysis also 
indicates that eight exposures to sound levels likely to result in 
Level A Harassment may occur from active acoustic stressors and sound 
or energy from explosions. Northern fur seals are common in SOCAL. 
Behavioral responses can range from a mild orienting response, or a 
shifting of attention, to flight and panic. Research and observations 
show that pinnipeds in the water are tolerant of anthropogenic noise 
and activity. 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 exposure.
    A small population breeds on San Miguel Island, outside of the 
SOCAL Range Complex.
    Northern Elephant Seal--The Navy's acoustic analysis indicates that 
25,228 exposures of northern elephant seals to sound levels likely to 
result in Level B Harassment may occur from sonar and other active 
acoustic stressors associated with training and testing activities in 
the SOCAL Range Complex and sound or energy from explosions. Analysis 
also indicates that 27 exposures to sound levels likely to result in 
Level A Harassment may occur from active acoustic stressors and sound 
or energy from explosions. The majority of predicted effects would be 
from anti-submarine warfare events involving surface ships, submarines, 
and hull mounted sonar, while a small percentage of effects would be 
from mine countermeasure events. Northern elephant seals are common in 
SOCAL and the proposed take is less than 21 percent of the California 
breeding population. Behavioral responses can range from a mild 
orienting response, or a shifting of attention, to flight and panic. 
Research and observations show that pinnipeds in the water are tolerant 
of anthropogenic noise and activity. 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 exposure.
    Different age classes of northern elephant seals haul out on the 
Channel Islands within SOCAL and spend 8-10 months at sea each year.
    Hawaiian Monk Seal--The Navy's acoustic analysis indicates that 
1,650 exposures of Hawaiian monk seals (listed as endangered under the 
ESA) to sound levels likely to result in Level B harassment may occur 
from sonar or other active acoustic stressors associated with training 
and testing activities in HRC. No exposures to sound levels likely to 
result in Level A harassment are expected to occur and takes from 
injury or mortality are not requested or proposed for authorization. 
The majority of exposures from testing have ranges to TTS less than 50 
m. Behavioral effects are not expected to be significant because (1) 
Significant behavioral effects are more likely at higher received 
levels within a few kilometers of the source, (2) Hawaiian monk seals 
may avoid the activity area; and (3) mitigation measures would be 
implemented. Hawaiian monk seals predominantly occur in the 
Northwestern Hawaiian Islands and the Papahanaumokuakea National Marine 
Monument, which is outside of the main Hawaii Operating Area. Ranges to 
TTS for hull mounted sonars can be on the order of several kilometers 
for monk seals, and some behavioral impacts could take place at 
distances exceeding 173 km, although significant behavioral effects are 
much more likely at higher received levels within a few kilometers of 
the sound source and therefore, the majority of behavioral effects are 
not expected to be significant. Activities involving sound or energy 
from sonar and other active acoustic sources would not occur on shore 
in designated Hawaiian monk seal critical habitat where haul out and 
resting behavior occurs and would have no effect on critical habitat at 
sea.

[[Page 7040]]

Preliminary Determination

    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat and dependent 
upon the implementation of the mitigation and monitoring measures, NMFS 
preliminarily finds that the total taking from Navy training and 
testing exercises in the HSTT Study Area will have a negligible impact 
on the affected species or stocks. NMFS has proposed regulations for 
these exercises that prescribe the means of effecting the least 
practicable adverse impact on marine mammals and their habitat and set 
forth requirements pertaining to the monitoring and reporting of that 
taking.

Subsistence Harvest of Marine Mammals

    NMFS has preliminarily determined that the issuance of 5-year 
regulations and subsequent LOAs for Navy training and testing exercises 
in the HSTT Study Area would not have an unmitigable adverse impact on 
the availability of the affected species or stocks for subsistence use, 
since there are no such uses in the specified area.

ESA

    There are eight marine mammal species under NMFS jurisdiction that 
are listed as endangered or threatened under the ESA with confirmed or 
possible occurrence in the Study Area: blue whale, humpback whale, fin 
whale, sei whale, sperm whale, the Hawaiian insular stock of false 
killer whale, Guadalupe fur seal, and Hawaiian monk seal. The Navy will 
consult with NMFS pursuant to section 7 of the ESA, and NMFS will also 
consult internally on the issuance of LOAs under section 101(a)(5)(A) 
of the MMPA for HSTT activities. Consultation will be concluded prior 
to a determination on the issuance of the final rule and an LOA.

NMSA

    Some Navy activities may potentially affect resources within 
National Marine Sanctuaries. The Navy will continue to analyze 
potential impacts to sanctuary resources and has provided the analysis 
in the Navy's HSTT DEIS/OEIS to NOAA's Office of National Marine 
Sanctuaries. The Navy will initiate consultation with NOAA's Office of 
National Marine Sanctuaries pursuant to the requirements of the NMSA as 
warranted by ongoing analysis of the activities and their effects on 
sanctuary resources.

NEPA

    NMFS has participated as a cooperating agency on the HSTT DEIS/
OEIS, which was published on May 11, 2012. The HSTT DEIS/OEIS is posted 
on NMFS' Web site: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications. NMFS intends to adopt the Navy's final 
HSTT EIS/OEIS (FEIS/OEIS), if adequate and appropriate. Currently, we 
believe that the adoption of the Navy's HSTT FEIS/OEIS will allow NMFS 
to meet its responsibilities under NEPA for the issuance of regulations 
and LOAs for HSTT. If the Navy's HSTT FEIS/OEIS is deemed inadequate, 
NMFS would supplement the existing analysis to ensure that we comply 
with NEPA prior to the issuance of the final rule or LOA.

Classification

    The Office of Management and Budget has determined that this 
proposed 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 
proposed rule, if adopted, would 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. 
NMFS does not expect the issuance of these regulations or the 
associated LOAs to result in any impacts to small entities pursuant to 
the RFA. Because this action, if adopted, would directly affect the 
Navy and not a small entity, NMFS concludes the action would not result 
in a significant economic impact on a substantial number of small 
entities.

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: January 23, 2013.
Alan D. Risenhoover,
Director, Office of Sustainable Fisheries, performing the functions and 
duties of the Deputy Assistant Administrator for Regulatory Programs, 
National Marine Fisheries Service.

    For reasons set forth in the preamble, 50 CFR part 218 is proposed 
to be amended 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 follow:

    Authority: 16 U.S.C. 1361 et seq.

0
2. Subpart H is added 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 specified geographical region.
218.71 Effective dates and definitions.
218.72 Permissible methods of taking.
218.73 Prohibitions.
218.74 Mitigation.
218.75 Requirements for monitoring and reporting.
218.76 Applications for Letters of Authorization
218.77 Letters of Authorization.
218.78 Renewal of Letters of Authorization and Adaptive Management.
218.79 Modifications to Letters of Authorization

Subpart H--Taking and Importing Marine Mammals; U.S. Navy's Hawaii-
Southern California Training and Testing (HSTT)


Sec.  218.70  Specified activity and specified 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 outlined in paragraph 
(b) of this section and that occurs incidental to the activities 
described in paragraph (c) of this section.
    (b) The taking of marine mammals by the Navy is only authorized if 
it occurs within the HSTT Study Area, which is comprised of established 
operating and warning areas across the north-central Pacific Ocean, 
from Southern California west to Hawaii and the International Date Line 
(see Figure 1-1 in the Navy's application). The Study Area includes 
three existing range complexes: the Southern California (SOCAL) Range 
Complex, Hawaii Range Complex

[[Page 7041]]

(HRC), and Silver Strand Training Complex (SSTC). In addition, the 
Study Area also includes Navy pierside locations where sonar 
maintenance and testing occurs within the Study Area, and areas on the 
high seas that are not part of the range complexes, where training and 
testing may occur during vessel transit.
    (c) The taking of marine mammals by the Navy is only authorized if 
it occurs incidental to the following activities within the designated 
amounts of use:
    (1) Non-impulsive Sources Used During Training:
    (i) Mid-frequency (MF) Source Classes:
    (A) MF1--an average of 11,588 hours per year.
    (B) MF1K--an average of 88 hours per year.
    (C) MF2--an average of 3,060 hours per year.
    (D) MF2K--an average of 34 hours per year.
    (E) MF3--an average of 2,336 hours per year.
    (F) MF4--an average of 888 hours per year.
    (G) MF5--an average of 13,718 items per year.
    (H) MF11--an average of 1,120 hours per year.
    (I) MF12--an average of 1,094 hours per year.
    (ii) High-frequency (HF) and Very High-frequency (VHF) Source 
Classes:
    (A) HF1--an average of 1,754 hours per year.
    (B) HF4--an average of 4,848 hours per year.
    (iii) Anti-Submarine Warfare (ASW) Source Classes:
    (A) ASW1--an average of 224 hours per year.
    (B) ASW2--an average of 1,800 items per year.
    (C) ASW3--an average of 16,561 hours per year.
    (D) ASW4--an average of 1,540 items per year.
    (iv) Torpedoes (TORP) Source Classes:
    (A) TORP1--an average of 170 items per year.
    (B) TORP2--an average of 400 items per year.
    (2) Non-impulsive Sources Used During Testing:
    (i) Low-frequency (LF) Source Classes:
    (A) LF4--an average of 52 hours per year.
    (B) LF5--an average of 2,160 hours per year.
    (C) LF6--an average of 192 hours per year.
    (ii) Mid-frequency (MF):
    (A) MF1--an average of 180 hours per year.
    (B) MF1K--an average of 18 hours per year.
    (C) MF2--an average of 84 hours per year.
    (D) MF3--an average of 392 hours per year.
    (E) MF4--an average of 693 hours per year.
    (F) MF5--an average of 5,024 items per year.
    (G) MF6--an average of 540 items per year.
    (H) MF8--an average of 2 hours per year.
    (I) MF9--an average of 3,039 hours per year.
    (J) MF10--an average of 35 hours per year.
    (K) MF12--an average of 336 hours per year.
    (iii) High-frequency (HF) and Very High-frequency (VHF):
    (A) HF1--an average of 1,025 hours per year.
    (B) HF3--an average of 273 hours per year.
    (C) HF4--an average of 1,336 hours per year.
    (D) HF5--an average of 1,094 hours per year.
    (E) HF6--an average of 3,460 hours per year.
    (iv) ASW:
    (A) ASW1--an average of 224 hours per year.
    (B) ASW2--an average of 2,260 items per year.
    (C) ASW2H--an average of 255 hours per year.
    (D) ASW3--an average of 1,278 hours per year.
    (E) ASW4--an average of 477 items per year.
    (v) TORP:
    (A) TORP1--an average of 701 items per year.
    (B) TORP2--an average of 732 items per year.
    (vi) Acoustic Modems (M):
    (A) M3--an average of 4,995 hours per year.
    (vii) Swimmer Detection Sonar (SD):
    (A) SD1--an average of 38 hours per year.
    (viii) Airguns (AG):
    (A) AG--an average of 5 airgun uses per year.
    (ix) Synthetic Aperture Sonar (SAS):
    (A) SAS1--an average of 2,700 hours per year.
    (B) SAS2--an average of 4,956 hours per year.
    (C) SAS3--an average of 3,360 hours per year.
    (3) Annual Number of Impulsive Source Detonations During Training:
    (i) Explosive Classes:
    (A) E1 (0.1 to 0.25 lb NEW)--an average of 19,840 detonations per 
year.
    (B) E2 (1.26 to 0.5 lb NEW)--an average of 1,044 detonations per 
year.
    (C) E3 (0.6 to 2.5 lb NEW)--an average of 3,020 detonations per 
year.
    (D) E4 (>2.5 to 5 lb NEW)--an average of 668 detonations per year.
    (E) E5 (>5 to 10 lb NEW)--an average of 8,154 detonations per year.
    (F) E6 (>10 to 20 lb NEW)--an average of 538 detonations per year.
    (G) E7 (>20 to 60 lb NEW)--an average of 407 detonations per year.
    (H) E8 (>60 to 100 lb NEW)--an average of 64 detonations per year.
    (I) E9 (>100 to 250 lb NEW)--an average of 16 detonations per year.
    (J) E10 (>250 to 500 lb NEW)--an average of 19 detonations per 
year.
    (K) E11 (>500 to 650 lb NEW)--an average of 8 detonations per year.
    (L) E12 (>650 to 1,000 lb NEW)--an average of 224 detonations per 
year.
    (M) E13 (>1,000 to 1,740 lb NEW)--an average of 9 detonations per 
year.
    (ii) [Reserved]
    (4) Impulsive Source Detonations During Testing:
    (i) Explosive Classes:
    (A) E1 (0.1 to 0.25 lb NEW)--an average of 14,501 detonations per 
year.
    (B) E2 (0.26 to 0.5 lb NEW)--an average of 0 detonations per year.
    (C) E3 (0.6 to 2.5 lb NEW)--an average of 2,990 detonations per 
year.
    (D) E4 (>2.5 to 5 lb NEW)--an average of 753 detonations per year.
    (E) E5 (>5 to 10 lb NEW)--an average of 202 detonations per year.
    (F) E6 (>10 to 20 lb NEW)--an average of 37 detonations per year.
    (G) E7 (>20 to 60 lb NEW)--an average of 21 detonations per year.
    (H) E8 (>60 to 100 lb NEW)--an average of 12 detonations per year.
    (I) E9 (>100 to 250 lb NEW)--an average of 0 detonations per year.
    (J) E10 (>250 to 500 lb NEW)--an average of 31 detonations per 
year.
    (K) E11 (>500 to 650 lb NEW)--an average of 14 detonations per 
year.
    (L) E12 (>650 to 1,000 lb NEW)--an average of 0 detonations per 
year.
    (M) E13 (>1,000 to 1,740 lb NEW)--an average of 0 detonations per 
year.
    (ii) [Reserved]


Sec.  218.71  Effective dates and definitions.

    (a) Regulations are effective January 25, 2013 through Janaury 25, 
2018.
    (b) The following definitions are utilized in these regulations:
    (1) Uncommon Stranding Event (USE)--A stranding event that takes 
place during a major training exercise (MTE) and involves any one of 
the following:
    (i) Two or more individuals of any cetacean species (not including 
mother/calf pairs), unless of species of concern listed in Sec.  
218.71(b)(1)(ii) found dead or live on shore within a 2-day period and

[[Page 7042]]

occurring within 30 miles of one another.
    (ii) A single individual or mother/calf pair of any of the 
following marine mammals of concern: beaked whale of any species, Kogia 
spp., Risso's dolphin, melon-headed whale, pilot whale, humpback whale, 
sperm whale, blue whale, fin whale, sei whale, or monk seal.
    (iii) A group of two or more cetaceans of any species exhibiting 
indicators of distress.
    (2) Shutdown--The cessation of MFAS/HFAS operation or detonation of 
explosives within 14 nautical miles of any live, in the water, animal 
involved in a USE.


Sec.  218.72  Permissible methods of taking.

    (a) Under Letters of Authorization (LOAs) issued pursuant to Sec.  
218.77, the Holder of the Letter of Authorization may incidentally, but 
not intentionally, take marine mammals within the area described in 
Sec.  218.70, provided the activity is in compliance with all terms, 
conditions, and requirements of these regulations and the appropriate 
LOA.
    (b) The activities identified in Sec.  218.70(c) must be conducted 
in a manner that minimizes, to the greatest extent practicable, any 
adverse impacts on marine mammals and their habitat.
    (c) The incidental take of marine mammals under the activities 
identified in Sec.  218.70(c) is limited to the following species, by 
the identified method of take and the indicated number of times:
    (1) Level B Harassment for all Training Activities:
    (i) Mysticetes:
    (A) Blue whale (Balaenoptera musculus)--21,559 (an average of 4,312 
per year).
    (B) Bryde's whale (Balaenoptera edeni)--1,197 (an average of 240 
per year).
    (C) Fin whale (Balaenoptera physalus)--8,531 (an average of 1,707 
per year).
    (D) Gray whale (Eschrichtius robustus)--47,800 (an average of 9,560 
per year).
    (E) Humpback whale (Megaptera novaeangliae)--46,365 (an average of 
9,273 per year).
    (F) Minke whale (Balaenoptera acutorostrata)--4,030 (an average of 
806 per year).
    (G) Sei whale (Balaenoptera borealis)--2,996 (an average of 600 per 
year).
    (ii) Odontocetes:
    (A) Baird's beaked whale (Berardius bairdii)--22,100 (an average of 
4,420 per year).
    (B) Blainville's beaked whale (Mesoplodon densirostris)--48,172 (an 
average of 10,316 per year).
    (C) Bottlenose dolphin (Tursiops truncatus)--158,590 (an average of 
32,302 per year).
    (D) Cuvier's beaked whale (Ziphius cavirostris)--314,790 (an 
average of 66,246 per year).
    (E) Dwarf sperm whale (Kogia sima)--101,291 (an average of 22,359 
per year).
    (F) Dall's porpoise (Phocoenoidea dalli)--184,455 (an average of 
36,891 per year).
    (G) False killer whale (Pseudorca crassidens), Hawaii Insular--220 
(an average of 49 per year).
    (H) False killer whale (Pseudorca crassidens)--2,892 (an average of 
657 per year).
    (I) Fraser's dolphin (Lagenodelphis hosei)--8,809 (an average of 
2,009 per year).
    (J) Killer whale (Orcinus orca)--2,427 (an average of 503 per 
year).
    (K) Kogia spp.--64,715 (an average of 12,943 per year).
    (L) Long-beaked common dolphin (Delphinus capensis)--365,565 (an 
average of 73,113 per year).
    (M) Longman's beaked whale (Indopacetus pacificus)--17,296 (an 
average of 3,666 per year).
    (N) Melon-headed whale (Peponocephala electra)--6,733 (an average 
of 1,511 per year).
    (O) Mesoplodon beaked whales--9,970 (an average of 1,994 per year).
    (P) Northern right whale dolphin (Lissodelphis borealis)--257,980 
(an average of 51,596 per year).
    (Q) Pacific white-sided dolphin (Lagenorhynchus obliquidens)--
192,335 (an average of 38,467 per year).
    (R) Pantropical spotted dolphin (Stenella attenuata)--48,429 (an 
average of 10,887 per year).
    (S) Pygmy killer whale (Feresa attenuata)--2,603 (an average of 571 
per year).
    (T) Pygmy sperm whale (Kogia breviceps)--1,093 (an average of 229 
per year).
    (U) Risso's dolphin (Grampus griseus)--437,707 (an average of 
87,649 per year).
    (V) Rough-toothed dolphin (Steno bredanensis)--22,765 (an average 
of 5,131 per year).
    (W) Short-beaked common dolphin (Delphinus delphis)--4,996,410 (an 
average of 999,282 per year).
    (X) Short-finned pilot whale (Globicephala macrorhynchus)--42,300 
(an average of 9,458 per year).
    (Y) Sperm whale (Physeter macrocephalus)--15,920 (an average of 
3,332 per year).
    (Z) Spinner dolphin (Stenella longirostris)--11,060 (an average of 
2,212 per year).
    (AA) Striped dolphin (Stenella coerulealba)--33,147 (an average of 
7,043 per year).
    (iii) Pinnipeds:
    (A) California sea lion (Zalophus californianus)--634,805 (an 
average of 126,961 per year).
    (B) Guadalupe fur seal (Arctocephalus townsendi)--13,014 (an 
average of 2,603 per year).
    (C) Harbor seal (Phoca vitulina)--29,530 (an average of 5,906 per 
year).
    (D) Hawaiian monk seal (Monachus schauinslandi)--6,334 (an average 
of 1,292 per year).
    (E) Northern elephant seal (Mirounga angustirostris)--112,580 (an 
average of 22,516 per year).
    (F) Northern fur seal (Callorhinus ursinus)--100,415 (an average of 
20,083 per year).
    (2) Level A Harassment for all Training Activities:
    (i) Mysticetes:
    (A) Gray whale (Eschrichtius robustus)--10 (an average of 2 per 
year).
    (B) [Reserved].
    (ii) Odontocetes:
    (A) Dwarf sperm whale (Kogia sima)--214 (an average of 46 per 
year).
    (B) Dall's porpoise (Phocoenoidea dalli)--235 (an average of 47 per 
year).
    (C) Kogia spp.--165 (an average of 33 per year).
    (D) Long-beaked common dolphin (Delphinus capensis)--10 (an average 
of 2 per year).
    (E) Northern right whale dolphin (Lissodelphis borealis)--5 (an 
average of 1 per year).
    (F) Pacific white-sided dolphin (Lagenorhynchus obliquidens)--5 (an 
average of 1 per year).
    (G) Risso's dolphin (Grampus griseus)--5 (an average of 1 per 
year).
    (H) Short-beaked common dolphin (Delphinus delphis)--350 (an 
average of 70 per year).
    (iii) Pinnipeds:
    (A) California sea lion (Zalophus californianus)--125 (an average 
of 25 per year).
    (B) Harbor seal (Phoca vitulina)--55 (an average of 11 per year).
    (C) Northern elephant seal (Mirounga angustirostris)--110 (an 
average of 22 per year).
    (D) Northern fur seal (Callorhinus ursinus)--25 (an average of 5 
per year).
    (3) Mortality for all Training Activities:
    (i) No more than 35 mortalities (7 per year) applicable to any 
small odontocete or pinniped species from an impulse source.
    (ii) No more than 10 beaked whale mortalities (2 per year).
    (iii) No more than 12 large whale mortalities (no more than 4 in 
any given year) from vessel strike.

[[Page 7043]]

    (4) Level B Harassment for all Testing Activities:
    (i) Mysticetes:
    (A) Blue whale (Balaenoptera musculus)--2,140 (an average of 428 
per year).
    (B) Bryde's whale (Balaenoptera edeni)--90 (an average of 18 per 
year).
    (C) Fin whale (Balaenoptera physalus)--1,125 (an average of 225 per 
year).
    (D) Gray whale (Eschrichtius robustus)--12,850 (an average of 2,570 
per year).
    (E) Humpback whale (Megaptera novaeangliae)--4,605 (an average of 
921 per year).
    (F) Minke whale (Balaenoptera acutorostrata)--395 (an average of 79 
per year).
    (G) Sei whale (Balaenoptera borealis)--255 (an average of 51 per 
year).
    (ii) Odontocetes:
    (A) Baird's beaked whale (Berardius bairdii)--5,225 (an average of 
1,045 per year).
    (B) Blainville's beaked whale (Mesoplodon densirostris)--4,800 (an 
average of 960 per year).
    (C) Bottlenose dolphin (Tursiops truncatus)--17,565 (an average of 
3,513 per year).
    (D) Cuvier's beaked whale (Ziphius cavirostris)--34,340 (an average 
of 6,868 per year).
    (E) Dwarf sperm whale (Kogia sima)--11,880 (an average of 2,376 per 
year).
    (F) Dall's porpoise (Phocoenoidea dalli)--26,075 (an average of 
5,215 per year).
    (G) False killer whale (Pseudorca crassidens), Hawaii Insular--20 
(an average of 4 per year).
    (H) False killer whale (Pseudorca crassidens)--255 (an average of 
51 per year).
    (I) Fraser's dolphin (Lagenodelphis hosei)--225 (an average of 45 
per year).
    (J) Killer whale (Orcinus orca)--335 (an average of 67 per year).
    (K) Kogia spp.--6,160 (an average of 1,232 per year).
    (L) Long-beaked common dolphin (Delphinus capensis)--239,255 (an 
average of 47,851 per year).
    (M) Longman's beaked whale (Indopacetus pacificus)--2,180 (an 
average of 436 per year).
    (N) Melon-headed whale (Peponocephala electra)--620 (an average of 
124 per year).
    (O) Mesoplodon beaked whales--1,725 (an average of 345 per year).
    (P) Northern right whale dolphin (Lissodelphis borealis)--28,645 
(an average of 5,729 per year).
    (Q) Pacific white-sided dolphin (Lagenorhynchus obliquidens)--
24,620 (an average of 4,924 per year).
    (R) Pantropical spotted dolphin (Stenella attenuata)--3,425 (an 
average of 685 per year).
    (S) Pygmy killer whale (Feresa attenuata)--305 (an average of 61 
per year).
    (T) Pygmy sperm whale (Kogia breviceps)--585 (an average of 117 per 
year).
    (U) Risso's dolphin (Grampus griseus)--44,260 (an average of 8,852 
per year).
    (V) Rough-toothed dolphin (Steno bredanensis)--2,050 (an average of 
410 per year).
    (W) Short-beaked common dolphin (Delphinus delphis)--613,740 (an 
average of 122,748 per year).
    (X) Short-finned pilot whale (Globicephala macrorhynchus)--4,380 
(an average of 876 per year).
    (Y) Sperm whale (Physeter macrocephalus)--1,315 (an average of 263 
per year).
    (Z) Spinner dolphin (Stenella longirostris)--835 (an average of 167 
per year).
    (AA) Striped dolphin (Stenella coerulealba)--6,335 (an average of 
1,267 per year).
    (iii) Pinnipeds:
    (A) California sea lion (Zalophus californianus)--65,190 (an 
average of 13,038 per year).
    (B) Guadalupe fur seal (Arctocephalus townsendi)--1,345 (an average 
of 269 per year).
    (C) Harbor seal (Phoca vitulina)--4,460 (an average of 892 per 
year).
    (D) Hawaiian monk seal (Monachus schauinslandi)--1,790 (an average 
of 358 per year).
    (E) Northern elephant seal (Mirounga angustirostris)--13,560 (an 
average of 2,712 per year).
    (F) Northern fur seal (Callorhinus ursinus)--5,440 (an average of 
1,088 per year).
    (5) Level A Harassment for all Testing Activities:
    (i) Mysticetes:
    (A) Gray whale (Eschrichtius robustus)--5 (an average of 1 per 
year).
    (B) [Reserved].
    (ii) Odontocetes:
    (A) Dwarf sperm whale (Kogia sima)--140 (an average of 28 per 
year).
    (B) Dall's porpoise (Phocoenoidea dalli)--160 (an average of 32 per 
year).
    (C) Kogia spp.--30 (an average of 6 per year).
    (D) Long-beaked common dolphin (Delphinus capensis)--10 (an average 
of 2 per year).
    (E) Northern right whale dolphin (Lissodelphis borealis)--5 (an 
average of 1 per year).
    (F) Pacific white-sided dolphin (Lagenorhynchus obliquidens)--5 (an 
average of 1 per year).
    (G) Pantropical spotted dolphin (Stenella attenuata)--10 (an 
average of 2 per year).
    (H) Pygmy sperm whale (Kogia breviceps)--5 (an average of 1 per 
year).
    (I) Risso's dolphin (Grampus griseus)--5 (an average of 1 per 
year).
    (J) Short-beaked common dolphin (Delphinus delphis)--200 (an 
average of 40 per year).
    (K) Spinner dolphin (Stenella longirostris)--5 (an average of 1 per 
year).
    (L) Striped dolphin (Stenella coerulealba)--5 (an average of 1 per 
year).
    (iii) Pinnipeds:
    (A) California sea lion (Zalophus californianus)--85 (an average of 
17 per year).
    (B) Harbor seal (Phoca vitulina)--15 (an average of 3 per year).
    (C) Northern elephant seal (Mirounga angustirostris)--25 (an 
average of 5 per year).
    (D) Northern fur seal (Callorhinus ursinus)--15 (an average of 3 
per year).
    (3) Mortality for all Testing Activities:
    (i) No more than 95 mortalities (an average of 19 per year) 
applicable to any small odontocete or pinniped species from an impulse 
source.
    (ii) No more than 3 large whale mortalities (no more than 2 in any 
given year) from vessel strike.


Sec.  218.73  Prohibitions.

    Notwithstanding takings contemplated in Sec.  218.72 and authorized 
by an LOA issued under Sec. Sec.  216.106 and 218.77 of this chapter, 
no person in connection with the activities described in Sec.  218.70 
may:
    (a) Take any marine mammal not specified in Sec.  218.72(c);
    (b) Take any marine mammal specified in Sec.  218.72(c) other than 
by incidental take as specified in Sec.  218.72(c);
    (c) Take a marine mammal specified in Sec.  218.72(c) if such 
taking results in more than a negligible impact on the species or 
stocks of such marine mammal; or
    (d) Violate, or fail to comply with, the terms, conditions, and 
requirements of these regulations or an LOA issued under Sec. Sec.  
216.106 and 218.77.


Sec.  218.74  Mitigation.

    (a) When conducting training and testing activities, as identified 
in Sec.  218.70, the mitigation measures contained in the LOA issued 
under Sec. Sec.  216.106 and 218.77 of this chapter must be 
implemented. These mitigation measures include, but are not limited to:
    (1) Lookouts. The following are protective measures concerning the 
use of lookouts.

[[Page 7044]]

    (i) Lookouts positioned on surface ships will be dedicated solely 
to diligent observation of the air and surface of the water. Their 
observation objectives will include, but are not limited to, detecting 
the presence of biological resources and recreational or fishing boats, 
observing buffer zones, and monitoring for vessel and personnel safety 
concerns.
    (ii) Lookouts positioned in aircraft or on boats will, to the 
maximum extent practicable and consistent with aircraft and boat safety 
and training and testing requirements, comply with the observation 
objectives described above in Sec.  218.74 (a)(1)(i).
    (iii) Lookout measures for non-impulsive sound:
    (A) With the exception of vessels less than 65 ft (20 m) in length 
and the Littoral Combat Ship (and similar vessels which are minimally 
manned), ships using low-frequency or hull-mounted mid-frequency active 
sonar sources associated with anti-submarine warfare and mine warfare 
activities at sea will have two lookouts at the forward position of the 
vessel. For the purposes of this rule, low-frequency active sonar does 
not include surface towed array surveillance system low-frequency 
active sonar.
    (B) While using low-frequency or hull-mounted mid-frequency active 
sonar sources associated with anti-submarine warfare and mine warfare 
activities at sea, vessels less than 65 ft (20 m) in length and the 
Littoral Combat Ship (and similar vessels which are minimally manned) 
will have one lookout at the forward position of the vessel due to 
space and manning restrictions.
    (C) Ships conducting active sonar activities while moored or at 
anchor (including pierside testing or maintenance) will maintain one 
lookout.
    (D) Ships or aircraft conducting non-hull-mounted mid-frequency 
active sonar, such as helicopter dipping sonar systems, will maintain 
one lookout.
    (E) Surface ships or aircraft conducting high-frequency or non-
hull-mounted mid-frequency active sonar activities associated with 
anti-submarine warfare and mine warfare activities at sea will have one 
lookout.
    (iii) Lookout measures for explosives and impulsive sound:
    (A) Aircraft conducting IEER sonobuoy activities will have one 
lookout.
    (B) Surface vessels conducting anti-swimmer grenade activities will 
have one lookout.
    (C) During general mine countermeasure and neutralization 
activities using up to a 500-lb net explosive weight detonation (bin 
E10 and below), vessels greater than 200 ft will have two lookouts, 
while vessels less than 200 ft will have one lookout.
    (D) General mine countermeasure and neutralization activities using 
a 501 to 650-lb net explosive weight detonation (bin E11), will have 
two lookouts. One lookout will be positioned in an aircraft and one in 
a support vessel.
    (E) Mine neutralization activities involving diver-placed charges 
using up to a 20-lb net explosive weight detonation will have one 
lookout.
    (F) Mine neutralization activities involving diver-placed charges 
using a 21 to 100-lb net explosive weight detonation (E8) will have two 
lookouts. One lookout will be positioned in each of the two support 
vessels. If aircraft are used, the pilot or member of the aircrew will 
serve as an additional lookout. The divers placing the charges on mines 
will report all marine mammal sightings to their dive support vessel.
    (G) When mine neutralization activities using diver-placed charges 
with up to a 20-lb net explosive weight detonation (bin E6) are 
conducted with a time-delay firing device, four lookouts will be used. 
Two lookouts will be positioned in each of two small rigid hull 
inflatable boats. When aircraft are used, the pilot or member of the 
aircrew will serve as an additional lookout. The divers placing the 
charges on mines will report all marine mammal sightings to their dive 
support vessel.
    (H) Surface vessels conducting line charge testing will have one 
lookout.
    (I) Surface vessels or aircraft conducting small- and medium-
caliber gunnery exercises will have one lookout.
    (J) Surface vessels or aircraft conducting large-caliber gunnery 
exercises will have one lookout.
    (K) Surface vessels or aircraft conducting missile exercises 
against surface targets will have one lookout.
    (L) Aircraft conducting bombing exercises will have one lookout.
    (M) During explosive torpedo testing, one lookout will be used and 
positioned in an aircraft.
    (N) During sinking exercises, two lookouts will be used. One 
lookout will be positioned in an aircraft and one on a surface vessel.
    (O) Each surface vessel supporting at-sea explosive testing will 
have at least one lookout.
    (P) During pile driving, one lookout will be used and positioned on 
the platform that will maximize the potential for marine mammal 
sightings (e.g., the shore, an elevated causeway, or on a ship).
    (Q) Surface vessels conducting explosive and non-explosive large-
caliber gunnery exercises will have one lookout. This may be the same 
lookout used during large-caliber gunnery exercises with a surface 
target.
    (iv) Lookout measures for physical strike and disturbance:
    (A) While underway, surface ships will have at least one lookout.
    (B) During activities using towed in-water devices, one lookout 
will be used.
    (C) Activities involving non-explosive practice munitions (e.g., 
small-, medium-, and large-caliber gunnery exercises) using a surface 
target will have one lookout.
    (D) During activities involving non-explosive bombing exercises, 
one lookout will be used.
    (2) Mitigation Zones. The following are protective measures 
concerning the implementation of mitigation zones.
    (i) Mitigation zones will be measured as the radius from a source 
and represent a distance to be monitored.
    (ii) Visual detections of marine mammals within a mitigation zone 
will be communicated immediately to a watch station for information 
dissemination and appropriate action.
    (iii) Mitigation zones for non-impulsive sound: \1\
---------------------------------------------------------------------------

    \1\ The mitigation zone would be 200 yd for low-frequency non-
hull mounted sources in bin LF4.
---------------------------------------------------------------------------

    (A) When marine mammals are detected by any means, the Navy shall 
ensure that low-frequency and hull-mounted mid-frequency active sonar 
transmission levels are limited to at least 6 dB below normal operating 
levels if any detected marine mammals are within 1,000 yd (914 m) of 
the sonar dome (the bow).
    (B) The Navy shall ensure that low-frequency and hull-mounted mid-
frequency active sonar transmissions are limited to at least 10 dB 
below the equipment's normal operating level if any detected marine 
mammals are within 500 yd (457 m) of the sonar dome.
    (C) The Navy shall ensure that low-frequency and hull-mounted mid-
frequency active sonar transmissions are ceased if any detected marine 
mammals are within 200 yd (183 m) of the sonar dome. Transmissions will 
not resume until the marine mammal has been seen to leave the area, has 
not been detected for 30 minutes, or the vessel has transited more than 
2,000 yd beyond the location of the last detection.
    (D) When marine mammals are detected by any means, the Navy shall 
ensure that high-frequency and non-hull-mounted mid-frequency active 
sonar transmission levels are ceased if

[[Page 7045]]

any detected marine mammals are within 200 yd (183 m) of the source. 
Transmissions will not resume until the marine mammal has been seen to 
leave the area, has not been detected for 30 minutes, or the vessel has 
transited more than 2,000 yd beyond the location of the last detection.
    (E) Special conditions applicable for dolphins and porpoises only: 
If, after conducting an initial maneuver to avoid close quarters with 
dolphins or porpoises, the Officer of the Deck concludes that dolphins 
or porpoises are deliberately closing to ride the vessel's bow wave, no 
further mitigation actions are necessary while the dolphins or 
porpoises continue to exhibit bow wave riding behavior.
    (F) Prior to start up or restart of active sonar, operators shall 
check that the mitigation zone radius around the sound source is clear 
of marine mammals.
    (G) Generally, the Navy shall operate sonar at the lowest 
practicable level, not to exceed 235 dB, except as required to meet 
tactical training objectives.
    (iv) Mitigation zones for explosive and impulsive sound:
    (A) A mitigation zone with a radius of 600 yd (549 m) shall be 
established for IEER sonobuoys (bin E4).
    (B) A mitigation zone with a radius of 350 yd (320 m) shall be 
established for explosive sonobuoys using 0.6 to 2.5 lb net explosive 
weight (bin E3).
    (C) A mitigation zone with a radius of 200 yd (183 m) shall be 
established for anti-swimmer grenades (bin E2).
    (D) A mitigation zone ranging from 350 yd (320 m) to 850 yd (777 
m), dependent on charge size, shall be established for mine 
countermeasure and neutralization activities using positive control 
firing devices. Mitigation zone distances are specified for charge size 
in Table 11-2 of the Navy's application.
    (E) A mitigation zone with a radius of 1,000 yd (915 m) shall be 
established for mine neutralization diver placed mines using time-delay 
firing devices (bin E6).
    (F) A mitigation zone with a radius of 900 yd (823 m) shall be 
established for ordnance testing (line charge testing) (bin E4).
    (G) A mitigation zone with a radius of 200 yd (183 m) shall be 
established for small- and medium-caliber gunnery exercises with a 
surface target (bin E2).
    (H) A mitigation zone with a radius of 600 yd (549 m) shall be 
established for large-caliber gunnery exercises with a surface target 
(bin E5).
    (I) A mitigation zone with a radius of 900 yd (823 m) shall be 
established for missile exercises with up to 250 lb net explosive 
weight and a surface target (bin E9).
    (J) A mitigation zone with a radius of 2,000 yd (1.8 km) shall be 
established for missile exercises with 251 to 500 lb net explosive 
weight and a surface target (E10).
    (K) A mitigation zone with a radius of 2,500 yd (2.3 km) shall be 
established for bombing exercises (bin E12).
    (L) A mitigation zone with a radius of 2,100 yd (1.9 km) shall be 
established for torpedo (explosive) testing (bin E11).
    (M) A mitigation zone with a radius of 2.5 nautical miles shall be 
established for sinking exercises (bin E12).
    (N) A mitigation zone with a radius of 1,600 yd (1.4 km) shall be 
established for at-sea explosive testing (bin E5).
    (O) A mitigation zone with a radius of 60 yd (55 m) shall be 
established for elevated causeway system pile driving.
    (v) Mitigation zones for vessels and in-water devices:
    (A) A mitigation zone of 500 yd (457 m) for observed whales and 200 
yd (183 m) for all other marine mammals (except bow riding dolphins) 
shall be established for all vessel movement, providing it is safe to 
do so.
    (B) A mitigation zone of 250 yd (229 m) shall be established for 
all towed in-water devices, providing it is safe to do so.
    (vi) Mitigation zones for non-explosive practice munitions:
    (A) A mitigation zone of 200 yd (183 m) shall be established for 
small, medium, and large caliber gunnery exercises using a surface 
target.
    (B) A mitigation zone of 1,000 yd (914 m) shall be established for 
bombing exercises.
    (vii) Mitigation zones for the use of Navy sea lions:
    (A) If a monk seal is seen approaching or within 100 m of a Navy 
sea lion, the handler will hold the Navy sea lion in the boat or recall 
the Navy sea lion immediately if it has already been released.
    (3) Humpback Whale Cautionary Area
    (i) The Navy will maintain a 5-km (3.1-mi) buffer zone between 
December 15 and April 15 where conducting exercises will require 
authorization by the Commander, U.S. Pacific Fleet (CPF).
    (ii) If authorized, the CPF will provide specific direction on 
required mitigation prior to operational units transiting to and 
training in the area.
    (iii) The Navy will provide NMFS with advance notification of any 
mid-frequency active sonar training and testing activities in the 
humpback whale cautionary area.
    (4) Stranding Response Plan
    (i) The Navy shall abide by the letter of the ``Stranding Response 
Plan for Major Navy Training Exercises in the HSTT Study Area,'' to 
include the following measures:
    (A) Shutdown Procedures--When an Uncommon Stranding Event (USE--
defined in Sec.  218.71(b)(1)) occurs during a Major Training Exercise 
(MTE) in the HSTT Study Area, the Navy shall implement the procedures 
described below.
    (1) The Navy shall implement a shutdown (as defined Sec.  
218.71(b)(2)) when advised by a NMFS Office of Protected Resources 
Headquarters Senior Official designated in the HSTT Study Area 
Stranding Communication Protocol that a USE involving live animals has 
been identified and that at least one live animal is located in the 
water. NMFS and the Navy will maintain a dialogue, as needed, regarding 
the identification of the USE and the potential need to implement 
shutdown procedures.
    (2) Any shutdown in a given area shall remain in effect in that 
area until NMFS advises the Navy that the subject(s) of the USE at that 
area die or are euthanized, or that all live animals involved in the 
USE at that area have left the area (either of their own volition or 
herded).
    (3) If the Navy finds an injured or dead animal floating at sea 
during an MTE, the Navy shall notify NMFS immediately or as soon as 
operational security considerations allow. The Navy shall provide NMFS 
with species or description of the animal(s), the condition of the 
animal(s), including carcass condition if the animal(s) is/are dead, 
location, time of first discovery, observed behavior (if alive), and 
photo or video (if available). Based on the information provided, NFMS 
will determine if, and advise the Navy whether a modified shutdown is 
appropriate on a case-by-case basis.
    (4) In the event, following a USE, that qualified individuals are 
attempting to herd animals back out to the open ocean and animals are 
not willing to leave, or animals are seen repeatedly heading for the 
open ocean but turning back to shore, NMFS and the Navy shall 
coordinate (including an investigation of other potential anthropogenic 
stressors in the area) to determine if the proximity of mid-frequency 
active sonar training activities or explosive detonations, though 
farther than 14 nautical miles from the distressed animal(s), is likely 
contributing to the animals' refusal to return to the open water. If 
so, NMFS and the Navy will further coordinate to determine what 
measures are necessary to improve the probability that the animals will 
return

[[Page 7046]]

to open water and implement those measures as appropriate.
    (B) Within 72 hours of NMFS notifying the Navy of the presence of a 
USE, the Navy shall provide available information to NMFS (per the HSTT 
Study Area Communication Protocol) regarding the location, number and 
types of acoustic/explosive sources, direction and speed of units using 
mid-frequency active sonar, and marine mammal sightings information 
associated with training activities occurring within 80 nautical miles 
(148 km) and 72 hours prior to the USE event. Information not initially 
available regarding the 80-nautical miles (148-km), 72-hour period 
prior to the event will be provided as soon as it becomes available. 
The Navy will provide NMFS investigative teams with additional relevant 
unclassified information as requested, if available.
    (b) [Reserved]


Sec.  218.75  Requirements for monitoring and reporting.

    (a) As outlined in the HSTT Study Area Stranding Communication 
Plan, the Holder of the Authorization 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 injury of any marine mammals, or in any take of marine 
mammals not identified in Sec.  218.71.
    (b) The Holder of the LOA must conduct all monitoring and required 
reporting under the LOA, including abiding by the HSTT Monitoring Plan.
    (c) General Notification of Injured or Dead Marine Mammals--Navy 
personnel shall ensure that NMFS (regional stranding coordinator) is 
notified immediately (or as soon as operational security considerations 
allow) if an injured or dead marine mammal is found during or shortly 
after, and in the vicinity of, a Navy training or testing activity 
utilizing mid- or high-frequency active sonar, or underwater explosive 
detonations. The Navy shall provide NMFS with species or description of 
the animal(s), the condition of the animal(s) (including carcass 
condition if the animal is dead), location, time of first discovery, 
observed behaviors (if alive), and photo or video (if available). The 
Navy shall consult the Stranding Response Plan to obtain more specific 
reporting requirements for specific circumstances.
    (d) Annual HSTT Monitoring Plan Report--The Navy shall submit an 
annual report describing the implementation and results (through 
November of the same year) of the HSTT Monitoring Plan, described in 
Sec.  218.75. Data collection methods will be standardized across range 
complexes and study areas to allow for comparison in different 
geographic locations. Although additional information will be gathered, 
the protected species observers collecting marine mammal data pursuant 
to the HSTT Monitoring Plan shall, at a minimum, provide the same 
marine mammal observation data required in Sec.  218.75. The HSTT 
Monitoring Plan may be provided to NMFS within a larger report that 
includes the required Monitoring Plan reports from multiple range 
complexes and study areas.
    (e) Annual HSTT Exercise Report--The Navy shall submit an annual 
HSTT Exercise Report. This report shall contain information identified 
in subsections Sec.  218.75 (e)(1-5).
    (1) MFAS/HFAS Major Training Exercises--This section shall contain 
the following information for Major Training Exercises (MTEs, which 
include RIMPAC, USWEX, and Multi Strike Group) conducted in the HRC:
    (i) Exercise Information (for each MTE):
    (A) Exercise designator.
    (B) Date that exercise began and ended.
    (C) Location.
    (D) Number and types of active sources used in the exercise.
    (E) Number and types of passive acoustic sources used in exercise.
    (F) Number and types of vessels, aircraft, etc., participating in 
exercise.
    (G) Total hours of observation by watchstanders.
    (H) Total hours of all active sonar source operation.
    (I) Total hours of each active sonar source bin.
    (J) Wave height (high, low, and average during exercise).
    (ii) Individual marine mammal sighting info (for each sighting in 
each MTE).
    (A) Location of sighting.
    (B) Species (if not possible, indication of whale/dolphin/
pinniped).
    (C) Number of individuals.
    (D) Calves observed (y/n).
    (E) Initial Detection Sensor.
    (F) Indication of specific type of platform observation made from 
(including, for example, what type of surface vessel, i.e., FFG, DDG, 
or CG).
    (G) Length of time observers maintained visual contact with marine 
mammal.
    (H) Wave height (in feet).
    (I) Visibility.
    (J) Sonar source in use (y/n).
    (K) Indication of whether animal is <200 yd, 200 to 500 yd, 500 to 
1,000 yd, 1,000 to 2,000 yd, or >2,000 yd from sonar source in 
paragraph (f)(1)(ii)(J) of this section.
    (L) Mitigation Implementation--Whether operation of sonar sensor 
was delayed, or sonar was powered or shut down, and how long the delay 
was.
    (M) If source in use (see paragraph (f)(1)(ii)(J) of this section) 
is hull-mounted, true bearing of animal from ship, true direction of 
ship's travel, and estimation of animal's motion relative to ship 
(opening, closing, parallel).
    (N) Observed behavior. Watchstanders shall report, in plain 
language and without trying to categorize in any way, the observed 
behavior of the animals (such as animal closing to bow ride, 
paralleling course/speed, floating on surface and not swimming, etc.).
    (iii) An evaluation (based on data gathered during all of the MTEs) 
of the effectiveness of mitigation measures designed to avoid exposing 
animals to mid-frequency active sonar. This evaluation shall identify 
the specific observations that support any conclusions the Navy reaches 
about the effectiveness of the mitigation.
    (2) ASW Summary. This section shall include the following 
information as summarized from both MTEs and non-major training 
exercises (i.e., unit-level exercises, such as TRACKEXs):
    (i) Total annual hours of each sonar source bin.
    (ii) Total hours (from December 15 through April 15) of hull-
mounted active sonar operation occurring in the dense humpback areas 
plus a 5-km buffer, but not including the Pacific Missile Range 
Facility.
    (iii) Total estimated annual hours of hull-mounted active sonar 
operation conducted in the Humpback Whale Cautionary area between 
December 15 and April 15.
    (iv) Cumulative Impact Report. To the extent practicable, the Navy, 
in coordination with NMFS, shall develop and implement a method of 
annually reporting non-major (i.e., other than RIMPAC, USWEX, or Multi-
Strike Group Exercises) training exercises utilizing hull-mounted 
sonar. The report shall present an annual (and seasonal, where 
practicable) depiction of non-major training exercises geographically 
across the HSTT Study Area. The Navy shall include (in the HSTT annual 
report) a brief annual progress update on the status of development 
until an agreed-upon (with NMFS) method has been developed and 
implemented.
    (3) SINKEXs. This section shall include the following information 
for each SINKEX completed that year:
    (i) Exercise information (gathered for each SINKEX):
    (A) Location.

[[Page 7047]]

    (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, etc., 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):
    (A) Location of sighting.
    (B) Species (if not possible, indicate whale, dolphin, or 
pinniped).
    (C) Number of individuals.
    (D) Whether calves were observed.
    (E) Initial detection sensor.
    (F) Length of time observers maintained visual contact with marine 
mammal.
    (G) Wave height.
    (H) Visibility.
    (I) Whether sighting was before, during, or after detonations/
exercise, and how many minutes before or after.
    (J) Distance of marine mammal from actual detonations (or target 
spot if not yet detonated).
    (K) Observed behavior--Lookouts will 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.
    (L) Resulting mitigation implementation--Indicate whether explosive 
detonations were delayed, ceased, modified, or not modified due to 
marine mammal presence and for how long.
    (M) If observation occurs while explosives are detonating in the 
water, indicate munition type in use at time of marine mammal 
detection.
    (4) IEER Summary. This section shall include an annual summary of 
the following IEER information:
    (i) Total number of IEER events conducted in the HSTT Study Area.
    (ii) Total expended/detonated rounds (buoys).
    (iii) Total number of self-scuttled IEER rounds.
    (5) Explosives Summary--To the extent practicable, the Navy will 
provide the information described below for all of their explosive 
exercises. Until the Navy is able to report in full the information 
below, they will provide an annual update on the Navy's explosive 
tracking methods, including improvements from the previous year.
    (i) Total annual number of each type of explosive exercises (of 
those identified as part of the ``specified activity'' in this final 
rule) conducted in the HSTT Study Area.
    (ii) Total annual expended/detonated rounds (missiles, bombs, etc.) 
for each explosive source bin.
    (g) Sonar Exercise Notification--The Navy shall submit to the NMFS 
Office of Protected Resources (specific contact information to be 
provided in LOA) either an electronic (preferably) or verbal report 
within fifteen calendar days after the completion of any major exercise 
(RIMPAC, USWEX, or Multi Strike Group) indicating:
    (1) Location of the exercise.
    (2) Beginning and end dates of the exercise.
    (3) Type of exercise (e.g., RIMPAC, USWEX, or Multi Strike Group).
    (h) HSTT Study Area 5-yr Comprehensive Report. The Navy shall 
submit to NMFS a draft report that analyzes and summarizes all of the 
multi-year marine mammal information gathered during ASW and explosive 
exercises for which annual reports are required (Annual HSTT Exercise 
Reports and HSTT Monitoring Plan reports). This report will be 
submitted at the end of the fourth year of the rule (November 2018), 
covering activities that have occurred through June 1, 2018.
    (i) Comprehensive National ASW Report. By June 2019, the Navy shall 
submit a draft Comprehensive National Report that analyzes, compares, 
and summarizes the active sonar data gathered (through January 1, 2019) 
from the lookouts in accordance with the Monitoring Plans for HSTT, 
AFTT, MITT, and NWTT.
    (j) The Navy shall respond to NMFS' comments and requests for 
additional information or clarification on the HSTT Comprehensive 
Report, the draft National ASW report, the Annual HSTT Exercise Report, 
or the Annual HSTT Monitoring Plan report (or the multi-Range Complex 
Annual Monitoring Plan Report, if that is how the Navy chooses to 
submit the information) if submitted within 3 months of receipt. These 
reports will be considered final after the Navy has addressed NMFS' 
comments or provided the requested information, or three months after 
the submittal of the draft if NMFS does not comment by then.


Sec.  218.76  Applications for Letters of Authorization.

    To incidentally take marine mammals pursuant to the regulations in 
this subpart, the U.S. citizen (as defined by Sec.  216.106) conducting 
the activity identified in Sec.  218.70(c) (the U.S. Navy) must apply 
for and obtain either an initial LOA in accordance with Sec.  218.77 or 
a renewal under Sec.  218.78.


Sec.  218.77  Letters of Authorization.

    (a) An LOA, unless suspended or revoked, will be valid for a period 
of time not to exceed the period of validity of this subpart.
    (b) Each LOA will set forth:
    (1) Permissible methods of incidental taking;
    (2) Means of effecting the least practicable adverse impact on the 
species, its habitat, and on the availability of the species for 
subsistence uses (i.e., mitigation); and
    (3) Requirements for mitigation, monitoring and reporting.
    (c) Issuance and renewal of the LOA will be based on a 
determination that the total number of marine mammals taken by the 
activity as a whole will have no more than a negligible impact on the 
affected species or stock of marine mammal(s).


Sec.  218.78  Renewal of Letters of Authorization and Adaptive 
Management.

    (a) A Letter of Authorization issued under Sec. Sec.  216.106 and 
218.77 for the activity identified in Sec.  218.70(c) will be renewed 
based upon:
    (1) Notification to NMFS that the activity described in the 
application submitted under Sec.  218.78 will be undertaken and that 
there will not be a substantial modification to the described work, 
mitigation, or monitoring undertaken during the upcoming period of 
validity;
    (2) Timely receipt (by the dates indicated in these regulations) of 
the monitoring reports required under Sec.  218.75(c-j); and
    (3) A determination by the NMFS that the mitigation, monitoring, 
and reporting measures required under Sec.  218.74 and the LOA issued 
under Sec. Sec.  216.106 and 218.78, were undertaken and will be 
undertaken during the upcoming period of validity of a renewed Letter 
of Authorization.
    (b) If a request for a renewal of an LOA issued under this Sec.  
216.106 and Sec.  218.78 indicates that a substantial modification, as 
determined by NMFS, to the described work, mitigation or monitoring 
undertaken during the upcoming season will occur, NMFS will provide the 
public a period of 30 days for review and comment on the request.

[[Page 7048]]

Review and comment on renewals of LOAs are restricted to:
    (1) New cited information and data indicating that the 
determinations made in this document are in need of reconsideration; 
and
    (2) Proposed changes to the mitigation and monitoring requirements 
contained in these regulations or in the current LOA.
    (c) A notice of issuance or denial of an LOA renewal will be 
published in the Federal Register.
    (d) NMFS, in response to new information and in consultation with 
the Navy, may modify the mitigation or monitoring measures in 
subsequent LOAs if doing so creates a reasonable likelihood of more 
effectively accomplishing the goals of mitigation and monitoring. Below 
are some of the possible sources of new data that could contribute to 
the decision to modify the mitigation or monitoring measures:
    (1) Results from the Navy's monitoring from the previous year 
(either from the HSTT Study Area or other locations).
    (2) Compiled results of Navy-funded research and development (R&D) 
studies (presented pursuant to the ICMP (Sec.  218.75(d)).
    (3) Results from specific stranding investigations (either from the 
HSTT Study Area or other locations, and involving coincident mid- or 
high-frequency active sonar or explosives training or not involving 
coincident use).
    (4) Results from the Long Term Prospective Study.
    (5) Results from general marine mammal and sound research (funded 
by the Navy (or otherwise)).


Sec.  216.79  Modifications to Letters of Authorization.

    (a) Except as provided in paragraph (b) of this section, no 
substantive modification (including withdrawal or suspension) to the 
LOA by NMFS, issued pursuant to Sec. Sec.  216.106 and 218.77 of this 
chapter and subject to the provisions of this subpart shall be made 
until after notification and an opportunity for public comment has been 
provided. For purposes of this paragraph, a renewal of an LOA under 
Sec.  218.78, without modification (except for the period of validity), 
is not considered a substantive modification.
    (b) If the Assistant Administrator determines that an emergency 
exists that poses a significant risk to the well-being of the species 
or stocks of marine mammals specified in Sec.  218.72(c), an LOA issued 
pursuant to Sec. Sec.  216.106 and 218.77 of this chapter may be 
substantively modified without prior notification and an opportunity 
for public comment. Notification will be published in the Federal 
Register within 30 days subsequent to the action.

[FR Doc. 2013-01808 Filed 1-25-13; 11:15 am]
BILLING CODE 3510-22-P