Federal Register, Volume 77 Issue 4 (Friday, January 6, 2012)

[Federal Register Volume 77, Number 4 (Friday, January 6, 2012)]
[Proposed Rules]
[Pages 842-894]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-33600]

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Vol. 77

Friday,

No. 4

January 6, 2012

Part II

Department of Commerce

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National Oceanic and Atmospheric Administration

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50 CFR Part 218

Taking and Importing Marine Mammals: Taking Marine Mammals Incidental
to U.S. Navy Operations of Surveillance Towed Array Sensor System Low
Frequency Active Sonar; Proposed Rule

Federal Register / Vol. 77 , No. 4 / Friday, January 6, 2012 /
Proposed Rules

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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 218

[Docket No. 110808485-1534-01]
RIN 0648-BB14

Taking and Importing Marine Mammals: Taking Marine Mammals
Incidental to U.S. Navy Operations of Surveillance Towed Array Sensor
System Low Frequency Active Sonar

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

ACTION: Proposed rule; request for comments.

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SUMMARY: NMFS has received a request from the U.S. Navy (Navy) for
authorization to take marine mammals, by harassment, incidental to
conducting operations of Surveillance Towed Array Sensor System
(SURTASS) Low Frequency Active (LFA) sonar in areas of the world's
oceans (with the exception of Arctic and Antarctic waters and certain
geographic restrictions), from August 16, 2012, through August 15,
2017. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is
proposing regulations to govern that take and requests information,
suggestions, and comments on these proposed regulations.

DATES: Comments and information must be received no later than February
6, 2012.

ADDRESSES: You may submit comments, identified by 0648-BB14, by any one
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,
Conservation and Education Division, Office of Protected Resources,
National Marine Fisheries Service, 1315 East-West Highway, Silver
Spring, MD 20910.
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. To help NMFS process and review comments
more efficiently, please use only one method to submit comments.

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

SUPPLEMENTARY INFORMATION:

Availability

The public may obtain an electronic copy of the Navy's application
by writing to the address specified above this section (see ADDRESSES),
telephoning the contact listed above this section (see FOR FURTHER
INFORMATION CONTACT), or by visiting the Internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications. The Navy
published a Federal Register Notice of Availability of a Draft
Supplemental Environmental Impact Statement/Supplemental Overseas
Environmental Impact Statement (DSEIS/SOEIS) for employment of SURTASS
LFA sonar on August 19, 2011. The public may view the document at:
http://www.surtass-lfa-eis.com. NMFS is participating in the
development of the Navy's DSEIS/SOEIS as a cooperating agency under the
National Environmental Policy Act of 1972.

Background

Sections 101(a)(5)(A) and (D) of the Marine Mammal Protection Act
of 1972, as amended (MMPA; 16 U.S.C. 1361 et seq.), direct the
Secretary of Commerce (Secretary) 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 during
periods of not more than five consecutive years each if certain
findings are made and 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 shall be granted if NMFS finds that the taking will
have a negligible impact on the species or stock(s), and will not have
an unmitigable adverse impact on the availability of the species or
stock(s) for subsistence uses (where relevant). The authorization must
set forth the permissible methods of taking, other means of effecting
the least practicable adverse impact on the species or stock and its
habitat, and requirements pertaining to the mitigation, monitoring and
reporting of such taking.
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) amended the MMPA by removing the ``small numbers'' and ``specified
geographical region'' provisions and amended the definition of
``harassment'' as it applies to a ``military readiness activity'' (as
defined in section 315(f) of Public Law 107-314; 16 U.S.C. 703 note) 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 behavior 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 August 17, 2011, NMFS received an application from the U.S. Navy
requesting authorization for the take of individuals of 94 species of
marine mammals (70 cetaceans and 24 pinnipeds), by harassment,
incidental to upcoming routine training and testing of the SURTASS LFA
sonar system, as well as the use of the system on a maximum of four
U.S. Naval ships during military operations in certain areas of the
Pacific, Atlantic, and Indian Oceans and the Mediterranean Sea from
August 16, 2012 through August 15, 2017. These routine training and
testing and military operations are classified as military readiness
activities. The Navy states, and NMFS concurs, that these military
readiness activities may incidentally take marine mammals present
within the Navy's operation areas by exposing them to sound from low-
frequency active sonar sources. The Navy requests authorization to take
individuals of 94 species of marine mammals by Level A and Level B
Harassment, although as discussed later in this document, Level A
Harassment will likely be avoided through the implementation of the
Navy's proposed mitigation measures.
This is NMFS' third rule making for SURTASS LFA sonar operations
under the MMPA. NMFS' current five-year

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regulations governing incidental takings incidental to SURTASS LFA
sonar activities and the related Letters of Authorizations (LOA) expire
on August 15, 2012. NMFS published the first rule, effective from
August 2002 through August 2007, on July 16, 2002 (67 FR 46712), and
published the second rule on August 21, 2007 (72 FR 46846). For this
proposed rule making, the Navy is proposing to conduct the same types
of sonar activities as they have conducted over the past nine years.

Description of the Specified Activities

Purpose and Background

The Navy's mission is to maintain, train, equip, and operate
combat-ready naval forces capable of accomplishing American strategic
objectives, deterring maritime aggression, and maintaining freedom of
the seas. Section 5062 of Title 10 of the United States Code directs
the Secretary of the Navy and Chief of Naval Operations (CNO) to ensure
the readiness of the U.S. naval forces.
The Secretary of the Navy and the CNO have established that anti-
submarine warfare (ASW) is a critical part of the Navy's mission that
requires access to both the open-ocean and littoral environments and
continual training to prepare for all potential threats. The Navy is
challenged by the increased difficulty in locating undersea threats
solely by using passive acoustic technologies due to the advancement
and use of quieting technologies in diesel-electric and nuclear
submarines. The range at which the Navy's ASW assets are able to
identify submarine threats is decreasing, and at the same time,
improvements in torpedo design are extending the effective weapons
range of subsea threats to the U.S. naval fleet.
To address these changing requirements for ASW readiness, the Navy
developed SURTASS LFA sonar, which provides the Navy with a reliable
and dependable system for long-range detection of quieter, harder-to-
find submarines. Because low-frequency (LF) sound travels in seawater
for greater distances than higher frequency sound, the Navy states that
the SURTASS LFA sonar system would meet the need for improved detection
and tracking of new-generation submarines at a longer range and would
maximize the opportunity for U.S. armed forces to safely react to, and
defend against, potential submarine threats while remaining a safe
distance beyond a submarine's effective weapons range. Thus, the Navy
believes that the active acoustic component in the SURTASS LFA sonar is
an important augmentation to its passive and tactical systems, as its
long-range detection capabilities can effectively counter the threat to
the U.S. Navy and national security interests posed by quiet, diesel
submarines.

Specified Activities

As previously mentioned, the Navy has requested MMPA authorization
to take marine mammals incidental to the operation of up to four
SURTASS LFA sonar systems for routine training and testing as well as
for the use of the system during military operations from August 16,
2012 through August 15, 2017. The SURTASS LFA sonar system is a long-
range, LF sonar (between 100 and 500 Hertz (Hz)) that has both active
and passive components (see the Description of SURTASS LFA Sonar
section later in this document). Use of the LFA sonar system could
occur in the Pacific, Atlantic and Indian Oceans, and the Mediterranean
Sea on a maximum of four naval surveillance vessels: the USNS ABLE,
USNS EFFECTIVE, USNS IMPECCABLE, and the USNS VICTORIOUS. The Navy
states that they will not operate SURTASS LFA sonar in Arctic and
Antarctic waters. Further, the Navy also proposes to operate SURTASS
LFA sonar such that the sound field does not exceed 180 decibels (dB)
within 22 kilometers (km) (13.7 miles (mi); 12 nautical miles (nm) of
land; or in proposed offshore biologically important areas (OBIA) for
marine mammals, identified later in this document, in the Navy's
application, and in the Navy's 2011 DSEIS/SOEIS (see Geographic
Restrictions section later in this document).
Because of uncertainties in the world's political climate, the Navy
cannot predict a detailed account of future operating locations and
conditions. However, for analytical purposes, the Navy has developed a
nominal annual deployment schedule and operational concept based on
current LFA sonar operations since January 2003 and projected naval
fleet requirements (See Table 1).
The Navy anticipates that a normal SURTASS LFA sonar deployment
schedule for a single vessel would involve approximately 294 days per
year at sea, which includes 240 days of active sonar transmissions and
54 days of transit. SURTASS LFA sonar would operate day and night in a
variety of weather conditions. NMFS refers the reader to Table 1 for
additional details on the nominal annual deployment schedule for
SURTASS LFA sonar vessels.

Table 1--Example Annual Deployment Schedule for One Surveillance Vessel
Using SURTASS LFA Sonar
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On mission Days Off mission Days
------------------------------------------------------------------------
Transit.......................... 54 In-Port Upkeep..... 40
Active Operations:
432 transmission hours based 240 Regular Overhaul... 31
on a 7.5% duty cycle.
--------- --------
Total Days on Mission.... 294 Total Days off 71
Mission.
------------------------------------------------------------------------

Potential SURTASS LFA Sonar Operational Areas

Figure 1 depicts the potential areas of operation for SURTASS LFA
sonar. Based on the Navy's current operational requirements, potential
operations for SURTASS LFA sonar vessels from August 2012 through
August 2017 would most likely include areas located in the Pacific,
Indian, and Atlantic Oceans and Mediterranean Sea.
The Navy will not operate SURTASS LFA sonar in polar regions (i.e.,
Arctic and Antarctic waters) of the world (see shaded areas in Figure
1). The Arctic Ocean, the Bering Sea (including Bristol Bay and Norton
Sound), portions of the Norwegian, Greenland, and Barents Seas north of
72[deg] North (N) latitude, plus Baffin Bay, Hudson Bay, and the Gulf
of St. Lawrence would be non-operational areas for SURTASS LFA sonar.
In the Antarctic, the Navy will not conduct SURTASS LFA operations in
areas south of 60[deg] South (S) latitude. The Navy has excluded polar
waters from operational planning because of the inherent inclement
weather conditions and the navigational and operational (equipment)
danger that icebergs pose to SURTASS LFA sonar vessels.

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[GRAPHIC] [TIFF OMITTED] TP06JA12.000

The Navy must anticipate, or predict, where they have to operate in
the next five years or so for the MMPA authorization. Naval forces are
presently operating in several areas strategic to U.S national and
international interests, including areas in the Atlantic Ocean, the
Mediterranean Sea, the Indian Ocean and Persian Gulf, and the Pacific
Rim. National Security needs may dictate that many of these operational
areas will be close to ports and choke points, such as entrances to
straits, channels, and canals. It is anticipated that many future naval
conflicts are likely to occur within littoral or coastal areas.
However, it is infeasible for the Navy to analyze all potential mission
areas for all species and stocks for all seasons. Instead, the Navy
projects where it intends to test, train, and operate for the next
five-year authorization period based on today's political climate and
provides NMFS with risk estimates for marine mammal stocks in the
proposed areas of operation.
For this third rulemaking, the Navy has modeled and analyzed 19
operational areas for SURTASS LFA operations that would be relevant to
U.S. national security interests (see Table 2). They include the
following modeled areas: East of Japan; north Philippine Sea; west
Philippine Sea; offshore Guam; Sea of Japan; East China Sea; the south
China Sea; the northwest Pacific Ocean; the Hawai'i Range Complex;
Offshore Southern California in the Southern California (SOCAL) Range
Complex; the western Atlantic in the Atlantic Fleet Active Sonar
(AFAST) Study Area/Jacksonville (JAX) operational area (OPAREA); the
eastern North Atlantic (western approach); the Mediterranean and
Ligurian Seas; the Arabian Sea; the Andaman Sea (approaches to the
Strait of Malacca); the Panama Canal (western approach); and the
northeast Australian Coast.

Table 2--Potential SURTASS LFA Sonar Operating Areas That the Navy Modeled for the DSEIS/OEIS (DoN, 2011) and
the MMPA LOA Application
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Location (latitude/ Location (latitude/
Modeled site longitude) Modeled site longitude)
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East of Japan................... 38[deg] N, 148[deg] E Hawaii South 19.5[deg] N, 158.5[deg] W.
(Hawai'i Range
Complex).
North Philippine Sea............ 29[deg] N, 136[deg] E Offshore Southern 32[deg] N, 120[deg] W.
California
(Southern
California (SOCAL)
Range Complex).
West Philippine Sea............. 22[deg] N, 124[deg] E Western Atlantic 30[deg] N, 78[deg] W.
(off Florida)
(Atlantic Fleet
Active Sonar
(AFAST) Study Area/
Jacksonville.
Offshore Guam (Mariana Islands 11[deg] N, 145[deg] E Eastern North 56.5[deg] N, 10[deg] W.
Range Complex, outside Mariana Atlantic (western
Trench). approach).
Sea of Japan.................... 39[deg] N, 132[deg] E Mediterranean Sea-- 43[deg] N, 8[deg] E.
Ligurian Sea.
East China Sea.................. 26[deg] N, 125[deg] E Arabian Sea........ 20[deg]N, 65[deg]E.
South China Sea................. 21[deg] N, 119[deg] E Andaman Sea 7.5[deg] N, 96[deg] E.
(approaches to the
Strait of Malacca).
NW Pacific 25[deg] to 40[deg] N. 30[deg] N, 165[deg] E Panama Canal 5[deg] N, 81[deg] W.
(western approach).
NW Pacific 10[deg] to 25[deg] N. 15[deg] N, 165[deg] E Northeast 23[deg] S, 155[deg] E.
Australian Coast.
Hawai'i North (Hawai'i Range 25[deg] N, 158[deg] W ...........................
Complex).
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Acoustic stimuli (i.e., increased underwater sound) generated
during the transmission of low-frequency acoustic signals by the
SURTASS LFA sonar system has the potential to cause take of marine
mammals in the operational areas. The operation of the SURTASS LFA
sonar system during at-sea operations would result in the generation of
sound or pressure waves in the water at or above levels that NMFS has
determined would result in take. This is the principal means of marine
mammal taking associated with these military readiness activities and
the Navy has requested an authorization to take 94 species of marine
mammals by Level A and Level B harassment. At no point are there
expected to be more than four systems in use, and thus this proposed
rule analyzes the impacts on marine mammals due to the deployment of up
to four LFA sonar systems from 2012 through 2017.
In addition to the use of active acoustic sources, the Navy's
activities include the operation and movement of vessels that are
necessary to conduct the routine training and testing as well as the
use of the system during military operations. This document also
analyzes the effects of this part of the activities. However, NMFS does
not anticipate take to result from collision with any of the four
SURTASS LFA vessels because each vessel moves at a relatively slow
speed, for a relatively short period of time. It is likely that any
marine mammal would be able to avoid the surveillance vessels.

Description of SURTASS LFA Sonar

SONAR is an acronym for Sound Navigation and Ranging, and its
definition includes any system (biological or mechanical) that uses
underwater sound, or acoustics, for detection, monitoring, and/or
communications. Active sonar is the transmission of sound energy for
the purpose of sensing the environment by interpreting features of
received signals. Active sonar detects objects by creating a sound
pulse or ping that is transmitted through the water and reflects off
the target, returning in the form of an echo. Passive sonar detects the
transmission of sound waves created by an object.
The SURTASS LFA sonar system is a long-range, all-weather sonar
system that has both active and passive components. LFA, the active
system component (which allows for the detection of an object that is
not generating noise), is comprised of source elements (called
projectors) suspended vertically on a cable beneath the surveillance
vessel. The projectors produce an active sound pulse (i.e., a ping) by
converting electrical energy to mechanical energy by setting up
vibrations or pressure disturbances within the water to produce a ping.
The Navy uses LFA as an augmentation to SURTASS operations when passive
system performance is inadequate. SURTASS, the passive part of the
system, uses hydrophones (i.e., underwater microphones) to detect sound
emitted or reflected from submerged targets, such as submarines. The
SURTASS hydrophones are mounted on a horizontal line array that is
towed behind the surveillance vessel. The Navy then processes and
evaluates the returning signals or echoes, which are usually below
background or ambient sound level, to identify and classify potential
underwater targets.

LFA Active Component

The active component of the SURTASS LFA sonar system consists of up
to 18 projectors suspended beneath the surveillance vessel in a
vertical line array. The expected water depth at the center of the
array is approximately 400 ft (121.9 m). The SURTASS LFA sonar
projectors transmit in the low-frequency band (between 100 and 500 Hz)
and the Navy will not transmit the SURTASS LFA sonar signal at a
frequency greater than 500 Hz. The source level of an individual
projector in the SURTASS LFA sonar array is approximately 215 dB re: 1
[micro]Pa at 1 m or less. (Sound pressure is the sound force per unit
area and is usually measured in micropascals ([mu]Pa), where one Pascal
(Pa) is the pressure resulting from a force of one newton exerted over
an area of one square meter. The commonly used reference pressure level
in underwater acoustics is 1 [mu]Pa at 1 m, and the units are decibels
(dB) re: 1 [mu]Pa at 1 m). Because of the physics involved in acoustic
beamforming (i.e., a method of mapping noise sources by differentiating
sound levels based upon the direction from which they originate) and
sound transmission loss processes, the SURTASS LFA sonar array cannot
have a sound pressure level (SPL) higher than the SPL of an individual
projector.
The SURTASS LFA sonar acoustic transmission is an omnidirectional
beam (a full 360 degrees ([deg])) in the horizontal plane. The LFA
sonar system also has a narrow vertical beam that the vessel's crew can
steer above or below the horizontal plane. The typical SURTASS LFA
sonar signal is not a constant tone, but rather a transmission of
various signal types that vary in frequency and duration (including
continuous wave (CW) and frequency-modulated (FM) signals). A complete
sequence of sound transmissions, also referred to by the Navy as a
``ping'' or a wavetrain, can last as short as six seconds (sec) to as
long as 100 sec with an average length of 60 sec. Within each ping, the
duration of any continuous frequency sound transmission is no longer
than 10 sec and the time between pings is typically from six to 15
minutes (min). Based on the Navy's historical operating parameters over
the past nine years, the average duty cycle (i.e., the ratio of sound
``on'' time to total time) for LFA sonar is normally 7.5 to 10 percent
and the duty cycle is not expected to exceed 20 percent.

Compact LFA Active Component

At present, the USNS IMPECCABLE is the only naval vessel with an
operational LFA sonar system. To meet future undersea warfare
requirements in littoral waters, the Navy has developed a compact LFA
(CLFA) sonar system now deployed on its three smaller surveillance
vessels (i.e., the USNS ABLE, EFFECTIVE, and VICTORIOUS). In the
application, the Navy indicates that the operational characteristics of
the active component CLFA are comparable to the existing LFA systems
and that the potential impacts from CLFA will be similar to the effects
from the existing LFA sonar system. CLFA consists of smaller projectors
that weigh 142,000 lbs (64,410 kilograms (kg)), which is 182,000 lbs
(82,554 kg) less that the mission weight of the LFA projectors on the
USNS IMPECCABLE. The CLFA sonar system also consists of up to 18
projectors suspended beneath the surveillance vessel in a vertical line
array and the CLFA sonar projectors transmit in the low-frequency band
(also between 100 and 500 Hz). Similar to the active component of the
LFA system, the source level of an individual projector in the CLFA
sonar array is approximately 215 dB re: 1 [micro]Pa or less.
For the analysis in this document, NMFS will use the term LFA to
refer to both the LFA sonar system and/or the CLFA sonar system, unless
otherwise specified.

SURTASS Passive Component

The passive component of the SURTASS LFA system consists of a
SURTASS Twin-line (TL-29A) horizontal line array mounted with
hydrophones. The Y-shaped array is 1,000 ft (305 m) in length and has
an operational depth of 500 to 1,500 ft (152.4 to 457.2 m). The SURTASS
LFA sonar vessel typically maintains a speed of at least 3.4 mph (5.6
km/hr; 3 knots (kts)) to tow the array astern of the vessel in the
correct horizontal configuration.

[[Page 846]]

High-Frequency Active Sonar

Although technically not part of the SURTASS LFA sonar system, the
Navy also proposes to use a high-frequency sonar system, called the
High Frequency Marine Mammal Monitoring sonar (HF/M3 sonar), developed
by the Navy and Scientific Solutions, Inc., to detect and locate marine
mammals within the SURTASS LFA sonar operational areas. This enhanced
commercial fish-finding sonar, mounted at the top of the SURTASS LFA
sonar vertical line array, has a source level of 220 dB re: 1 [micro]Pa
at 1 m with a frequency range from 30 to 40 kilohertz (kHz). The duty
cycle is variable, but is normally below between three to four percent
and the maximum pulse duration is 40 milliseconds. The HF/M3 sonar has
four transducers with 8[deg] horizontal and 10[deg] vertical
beamwidths, which sweep a full 360[deg] in the horizontal plane every
45 to 60 sec with a maximum range of approximately 1.2 mi (2 km).

Vessel Specifications

The Navy proposes to deploy the SURTASS LFA sonar system on a
maximum of four U.S. Naval ships: the USNS ABLE (T-AGOS 20), the USNS
EFFECTIVE (T-AGOS 21), the USNS IMPECCABLE (T-AGOS 23) and the USNS
VICTORIOUS (T-AGOS 19).
The USNS ABLE, EFFECTIVE, and VICTORIOUS, are twin-hulled ocean
surveillance ships. Each vessel has a length of 235 feet (ft) (71.6
meters (m)); a beam of 93.6 ft (28.5 m); a maximum draft of 25 ft (7.6
m); and a full load displacement of 3,396 tons (3,451 metric tons). A
twin-shaft diesel electric engine provides 3,200 horsepower (hp), which
drives two propellers.
The USNS IMPECCABLE, also a twin-hulled ocean surveillance ship,
has a length of 281.5 ft (85.8 m); a beam of 95.8 ft (29.2 m); a
maximum draft of 26 ft (7.9 m); and a full load displacement of 5,368
tons (5,454 metric tons). A twin-shaft diesel electric engine provides
5,000 hp, which drives two propellers.
The operational speed of each vessel during sonar operations will
be approximately 3.4 miles per hour (mph) (5.6 km per hour (km/hr); 3
kts) and each vessel's cruising speed outside of sonar operations would
be approximately 11.5 to 14.9 mph (18.5 to 24.1 km/hr; 10 to 13 kts).
The expected minimum water depth at which the SURTASS LFA vessel would
operate is 656.2 ft (200 m) and the vessel will generally travel in
straight lines or in oval-shaped (i.e., racetrack) patterns depending
on the operational scenario. Also, each SURTASS LFA sonar vessel would
operate independently of, or in conjunction with, other naval air,
surface or submarine assets.
Each vessel also has an observation area on the bridge from where
lookouts will monitor for marine mammals before and during the proposed
sonar operations. When stationed on the bridge of the USNS ABLE,
EFFECTIVE, or VICTORIOUS, the lookout's eye level will be approximately
32 ft (9.7 m) above sea level providing an unobstructed view around the
entire vessel. For the USNS IMPECCABLE, the lookout's eye level will be
approximately 45 ft (13.7 m) above sea level.

Description of Real-Time SURTASS LFA Sonar Sound Field Modeling

This section explains how the Navy will determine the propagation
of LFA sonar signals in the ocean and the distance from the SURTASS LFA
sonar source to the 180-dB re: 1 [micro]Pa at 1 m isopleth (i.e., the
basis for the proposed LFA sonar mitigation zone for marine mammals).
NMFS provides this description to aid the public's understanding of
this action. However, the actual physics governing the propagation of
SURTASS LFA sound signals is extremely complex and dependent on
numerous in-situ environmental factors.
Prior to commencing and during SURTASS LFA transmissions, the sonar
operators on the vessel will measure oceanic conditions (such as sea
water temperature, salinity, and depth) in the proposed action area.
This information is required for the sonar technicians to accurately
determine the speed at which sound travels and to determine the path
that the sound would take through the water column at a particular
location (i.e., the speed of sound in seawater varies directly with
depth, temperature, and salinity).
The sonar operators use the near-real time environmental data and
the Navy's underwater acoustic performance prediction models (updated
every 12 hours or more frequently when meteorological or oceanographic
conditions change) to generate a plot of sound speed versus depth,
typically referred to as a sound speed profile (SSP). The SSP enables
the technicians to determine the sound field by predicting the received
levels of sound at various distances from the SURTASS LFA sonar source
location. Modeling of the sound field in near-real time provides the
information necessary to modify SURTASS LFA operations, including the
delay or suspension of LFA sonar transmissions for mitigation.
Subchapter 3.1.2 of the SURTASS LFA Sonar 2011 DSEIS/SOEIS (DoN,
2011) discusses some of the environmental factors affecting sound
propagation. Appendix B of the 2001 SURTASS LFA Sonar FOEIS/EIS (DoN,
2001) also provides an understanding concerning the general conditions
of sound speed in the oceans. NMFS refers the public to these documents
at http://www.surtass-lfa-eis.com for additional information.

Comments and Responses

On August 30, 2011 NMFS published a notice of receipt of an
application for an LOA in the Federal Register (76 FR 53884) and
requested comments and information from the interested public for 30
days. During the 30-day comment period, NMFS received two comments. One
commenter opposed the project on the grounds that it would cause
mortality to marine mammals. NMFS notes that the Navy has not requested
lethal take of marine mammals in its application and, for the reasons
described in this document, NMFS does not anticipate that any mortality
will occur as a result of the Navy's activities. Therefore, the
proposed rule only envisions the authorization of Level A and Level B
harassment of marine mammals. The other comment, from an environmental
non-governmental organization, expressed concerns about the geographic
mitigation proposed in the Navy's DSEIS/SOEIS, focusing particularly on
the process for identifying proposed offshore biologically important
areas (OBIAs). NMFS undertook a systematic and scientifically
supportable process for identifying OBIAs for this proposed rule
making. This process is summarized in the Mitigation section of this
proposed rule and detailed in the Navy's DSEIS/SOEIS.
The Marine Mammal Commission (MMC) also submitted comments to the
Navy and NMFS. Generally, the MMC agreed that NMFS should propose
regulations governing the take of marine mammals incidental to
operation of SURTASS LFA sonar for a third five-year period. However,
the MMC recommended that the Navy amend its application and related
DSEIS/SOEIS to: (1) clarify the Navy's take request for marine mammals
by Level A harassment; and (2) specify the numbers of marine mammals
that could be taken by Level A and B harassment incidental to operating
SURTASS LFA sonar, rather than providing only the probabilities of such
takes. With respect to the first point, NMFS notes that the Navy's
application specifically requests authorization for Level A harassment
of

[[Page 847]]

marine mammals incidental to SURTASS LFA sonar operations.
With respect to the MMC's second point, the percentages given in
Tables 6 through 27 in the Navy's application are not probabilities,
but rather indicate the percent of the affected stock for a specific
marine mammal species. For the Navy's Level A and Level B harassment
take request, that percentage is then multiplied by the number of
animals in the relevant species or stock to arrive at an estimated
number of animals that may be harassed by SURTASS LFA sonar operations.
The Navy's approach to estimating Level A harassment and Level B
harassment takes is consistent with the approach used in previous rules
for SURTASS LFA sonar.
This proposed rule does not specify the number of marine mammals
that may be taken in the proposed locations because these are
determined annually through various inputs such as mission location,
mission duration, and season of operation. As with the previous two
rulemakings, this proposed rule analyzes a maximum of 12 percent takes
by Level B harassment per stock annually that will be taken per stock
annually, regardless of the number of LFA sonar vessels operating. The
Navy will use the 12 percent cap (i.e., the maximum percentage of a
stock that could be taken annually, not the probability of take) to
guide its mission planning and annual LOA applications. For the annual
applications for LOAs, the Navy proposes to present both the estimated
percentage of stock incidentally harassed as well as the estimated
number of animals that may be potentially harassed by SURTASS LFA
sonar.

Description of Marine Mammals in the Area of the Specified Activities

Ninety-four (94) marine mammal species or populations/stocks have
confirmed or possible occurrence within potential SURTASS LFA
operational areas in certain areas of the Pacific, Atlantic, and Indian
Oceans and the Mediterranean Sea. Twelve species of baleen whales
(mysticetes), 58 species of toothed whales, dolphins, or porpoises
(odontocetes), and 24 species of seals or sea lions (pinnipeds) could
be affected by SURTASS LFA sonar operations.
Fifteen of the 94 marine mammal species are listed as endangered
and three of the 94 marine mammal species are listed as threatened
under the Endangered Species Act of 1973 (ESA; 16 U.S.C. 1531 et seq.).
Marine mammal species under NMFS' jurisdiction listed as endangered
include: the blue whale (Balaenoptera musculus); fin whale
(Balaenoptera physalus); sei whale (Balaenoptera borealis); humpback
whale (Megaptera novaeangliae); bowhead whale (Balaena mysticetus);
North Atlantic right whale (Eubalaena glacialis); North Pacific right
whale (Eubalaena japonica); southern right whale (Eubalaena australis);
gray whale (Eschrichtius robustus); sperm whale (Physeter
macrocephalus); the Cook Inlet stock of beluga whale (Delphinapterus
leucas); the Southern Resident population of Killer whale (Orca
orcinus); the western distinct population segment (DPS) of the Steller
sea lion (Eumetopias jubatus); Mediterranean monk seal (Monachus
monachus); and Hawaiian monk seal (Monachus schauinslandi). Marine
mammal species under NMFS' jurisdiction listed as threatened include:
the eastern DPS of the Steller sea lion; the Guadalupe fur seal
(Arctocephalus townsendi) and the southern DPS of the spotted seal
(Phoca largha). The aforementioned threatened and endangered marine
mammal species also are depleted under the MMPA.
In addition, the Hawaiian insular DPS of false killer whale
(Pseudorca crassidens) is a candidate for proposed listing under the
ESA. Also, three of the 94 species are considered depleted under the
MMPA. They are: the western north Atlantic coastal stock of bottlenose
dolphin (Tursiops truncatus); the northeastern offshore stock of the
pantropical spotted dolphin (Stenella attenuata); and the eastern stock
of the spinner dolphin (Stenella longirostris).
Ringed seals (Phoca hispida), bearded seals (Erignathus barbatus),
Chinese river dolphins (Lipotes vexillifer) and vaquita (Phocoena
sinus) do not have stocks designated within potential SURTASS LFA sonar
operational areas (see Potential SURTASS LFA Operational Areas
section). The ringed seal is found in the Northern Hemisphere with a
circumpolar distribution ranging from 35[deg] N to the North Pole.
Bearded seals have a circumpolar distribution south of 85[deg] N
latitude, extending south into the southern Bering Sea in the Pacific
and into Hudson Bay and southern Labrador in the Atlantic. The
distribution of the Chinese river dolphin is limited to the main
channel of a river section between the cities of Jingzhou and Jiangyin.
The vaquita's distribution is restricted to the upper portion of the
northern Gulf of California, mostly within the Colorado River delta.
Based on the rare occurrence of these species in the Navy's designated
operational areas (i.e., outside of Arctic waters or outside of the
coastal standoff distance of 22 km (13. mi; 11.8 nmi)), the Navy and
NMFS do not anticipate any take of ringed seals, bearded seals, Chinese
river dolphins, and vaquita and therefore these species are not
addressed further in this document.
The U.S. Fish and Wildlife Service (USFWS) is responsible for
managing the following marine mammal species: southern sea otter
(Enhydra lutris), polar bear (Ursus maritimus), walrus (Odobenus
rosmarus), west African manatee (Trichechus senegalensis), Amazonian
manatee (Trichechus inunguis), west Indian manatee (Trichechus
manatus), and dugong (Dugong dugon). None of these species occur in
geographic areas that would overlap with SURTASS LFA sonar operational
areas. Therefore, the Navy has determined that routine training and
testing of SURTASS LFA sonar as well as the use of the system during
military operations would have no effect on the endangered or
threatened species or the critical habitat of the ESA-listed species
under the jurisdiction of the USFWS. These species are not considered
further in this notice.
Tables 3 through 21 summarize the abundance, status under the ESA,
and density estimates of the marine mammals that have confirmed or
possible occurrence within 19 SURTASS LFA sonar operating areas in the
Pacific, Indian, and Atlantic Oceans and Mediterranean Sea. The Navy
states that they selected these 19 areas based on relevance to national
security interests for this application. Because it is infeasible for
the Navy to model enough representative sites to cover all potential
SURTASS LFA sonar operating areas, the Navy provided 19 sites, based on
the current political climate, as examples of potential operating areas
in their application.
Information on how the density and stock/abundance estimates were
derived for the selected mission sites is in the Navy's application.
These data are derived from current, published source documentation,
and provide general area information for each mission area with
species-specific information on the animals that could occur in that
area, including estimates for their stock abundance and density. The
Navy developed the majority of the abundance and density estimates by
first using estimates from line-transect surveys that occurred in or
near each of the 19 model sites (e.g., Barlow, 2006). When density
estimates were not available from a survey in the operating area, the
Navy extrapolated density estimates from a region with similar
oceanographic characteristics to that operating area. For example, the
eastern

[[Page 848]]

tropical Pacific has been extensively surveyed and provides a
comprehensive understanding of marine mammals in temperate oceanic
waters (Ferguson and Barlow, 2001, 2003). Further, the Navy pooled
density estimates for species of the same genus if sufficient data are
not available to compute a density for individual species or the
species are difficult to distinguish at sea.

Table 3--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the East of Japan Operational Area
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Blue whale (Balaenoptera musculus)... NP...................... 9,250 0.0002 EN
Fin whale (Balaenoptera physalus).... NP...................... 9,250 0.0002 EN
Sei whale (Balaenoptera borealis).... NP...................... 8,600 0.0006 EN
Bryde's whale (Balaenoptera edeni)... WNP..................... 20,501 0.0006 NL
Minke whale (Balaenoptera WNP ``O'' Stock......... 25,049 0.0022 NL
acutorostrata).
North Pacific right whale (Eubalaena WNP..................... 922 < 0.00001 EN
japonica).
Sperm whale (Physeter macrocephalus). NP...................... 102,112 0.0010 EN
Pygmy sperm whale (Kogia breviceps) NP...................... 350,553 0.0031 NL
Dwarf sperm whale (Kogia sima).
Baird's beaked whale (Berardius WNP..................... 8,000 0.0029 NL
bairdii).
Cuvier's beaked whale (Ziphius NP...................... 90,725 0.0054 NL
cavirostris).
Ginkgo-toothed beaked whale NP...................... 22,799 0.0005 NL
(Mesoplodon ginkgodens).
Hubbs beaked whale (Mesoplodon NP...................... 22,799 0.0005 NL
carhubbsi).
False killer whale (Pseudorca WNP-Pelagic............. 16,668 0.0036 NL
crassidens).
Pygmy killer whale (Feresa attenuata) WNP..................... 30,214 0.0021 NL
Short-finned pilot whale WNP..................... 53,608 0.0128 NL
(Globicephala macrorhynchus).
Risso's dolphin (Grampus griseus).... WNP..................... 83,289 0.0097 NL
Common dolphin (Delphinus delphis)... WNP..................... 3,286,163 0.0761 NL
Fraser's dolphin (Lagenodelphis WNP..................... 220,789 0.0040 NL
hosei).
Bottlenose dolphin (Tursiops WNP..................... 168,791 0.0171 NL
truncatus).
Pantropical spotted dolphin (Stenella WNP..................... 438,064 0.0259 NL
attenuata).
Striped dolphin (Stenella WNP..................... 570,038 0.0111 NL
coeruleoalba).
Spinner dolphin (Stenella WNP..................... 1,015,059 0.0005 NL
longirostris).
Pacific white-sided dolphin WNP..................... 931,000 0.0082 NL
(Lagenorhynchus obliquidens).
Rough-toothed dolphin (Steno WNP..................... 145,729 0.0059 NL
bredanensis).
----------------------------------------------------------------------------------------------------------------
\1\ NP = north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 4--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the North Philippine Sea Operational Area
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Bryde's whale........................ WNP..................... 20,501 0.0006 NL
Minke whale.......................... WNP ``O'' Stock......... 25,049 0.0044 NL
North Pacific right whale............ WNP..................... 922 < 0.00001 EN
Sperm whale.......................... NP...................... 102,112 0.0028 EN
Pygmy sperm and Dwarf sperm whale.... NP...................... 350,553 0.0031 NL
Cuvier's beaked whale................ NP...................... 90,725 0.0054 NL
Blainville's beaked whale (Mesoplodon NP...................... 8,032 0.0005 NL
densirostris).
Ginkgo-toothed beaked whale.......... NP...................... 22,799 0.0005 NL
Killer whale (Orca orcinus).......... NP...................... 12,256 0.0004 NL
False killer whale................... WNP-Pelagic............. 16,668 0.0029 NL
Pygmy killer whale................... WNP..................... 30,214 0.0021 NL
Melon-headed whale (Peponocephala WNP..................... 36,770 0.0012 NL
electra).
Short-finned pilot whale............. WNP..................... 53,608 0.0153 NL
Risso's dolphin...................... WNP..................... 83,289 0.0106 NL
Common dolphin....................... WNP..................... 3,286,163 0.0562 NL
Fraser's dolphin..................... WNP..................... 220,789 0.0040 NL
Bottlenose dolphin................... WNP..................... 168,791 0.0146 NL
Pantropical spotted dolphin.......... WNP..................... 438,064 0.0137 NL
Striped dolphin...................... WNP..................... 570,038 0.0329 NL
Spinner dolphin...................... WNP..................... 1,015,059 0.0005 NL
Pacific white-sided dolphin.......... WNP..................... 931,000 0.0119 NL
Rough-toothed dolphin................ WNP..................... 145,729 0.0059 NL
----------------------------------------------------------------------------------------------------------------
\1\ NP = north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

[[Page 849]]

Table 5--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the West Philippine Sea Operational Area
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Fin whale............................ NP...................... 9,250 0.0002 EN
Bryde's whale........................ WNP..................... 20,501 0.0006 NL
Minke whale.......................... WNP ``O'' Stock......... 25,049 0.0033 NL
Humpback whale....................... WNP..................... 1,107 0.0008 EN
Sperm whale.......................... NP...................... 102,112 0.0010 EN
Pygmy sperm and Dwarf sperm whale.... NP...................... 350,553 0.0017 NL
Cuvier's beaked whale................ NP...................... 90,725 0.0003 NL
Blainville's beaked whale............ NP...................... 8,032 0.0005 NL
Ginkgo-toothed beaked whale.......... NP...................... 22,799 0.0005 NL
False killer whale................... WNP-Pelagic............. 16,668 0.0029 NL
Pygmy killer whale................... WNP..................... 30,214 0.0021 NL
Melon-headed whale................... WNP..................... 36,770 0.0012 NL
Short-finned pilot whale............. WNP..................... 53,608 0.0076 NL
Risso's dolphin...................... WNP..................... 83,289 0.0106 NL
Common dolphin....................... WNP..................... 3,286,163 0.0562 NL
Fraser's dolphin..................... WNP..................... 220,789 0.0040 NL
Bottlenose dolphin................... WNP..................... 168,791 0.0146 NL
Pantropical spotted dolphin.......... WNP..................... 438,064 0.0137 NL
Striped dolphin...................... WNP..................... 570,038 0.0164 NL
Spinner dolphin...................... WNP..................... 1,015,059 0.0005 NL
Pacific white-sided dolphin.......... WNP..................... 931,000 0.0245 NL
Rough-toothed dolphin................ WNP..................... 145,729 0.0059 NL
----------------------------------------------------------------------------------------------------------------
\1\ NP = north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 6--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Offshore Guam Operational Area
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Blue whale........................... ENP..................... 2,842 0.0001 EN
Fin whale............................ ENP..................... 9,250 0.0003 EN
Sei whale............................ NP...................... 8,600 0.0003 EN
Bryde's whale........................ WNP..................... 20,501 0.0004 NL
Minke whale.......................... WNP ``O'' Stock......... 25,049 0.0003 NL
Humpback whale....................... CNP..................... 10,103 0.0069 EN
Sperm whale.......................... NP...................... 102,112 0.0012 EN
Pygmy sperm and Dwarf sperm whale.... NP...................... 350,553 0.0101 NL
Cuvier's beaked whale................ NP...................... 90,725 0.0062 NL
Blainville's beaked whale............ NP...................... 8,032 0.0012 NL
Ginkgo-toothed beaked whale.......... NP...................... 22,799 0.0005 NL
Longman's beaked whale (Indopacetus CNP..................... 1,007 0.0004 NL
pacificus).
Killer whale......................... CNP..................... 349 0.0001 NL
False killer whale................... WNP-Pelagic............. 16,668 0.0011 NL
Pygmy killer whale................... WNP..................... 30,214 0.0001 NL
Melon-headed whale................... WNP..................... 36,770 0.0043 NL
Short-finned pilot whale............. WNP..................... 53,608 0.0016 NL
Risso's dolphin...................... WNP..................... 83,289 0.0010 NL
Common dolphin....................... WNP..................... 3,286,163 0.0021 NL
Fraser's dolphin..................... CNP..................... 10,226 0.0042 NL
Bottlenose dolphin................... WNP..................... 168,791 0.0002 NL
Pantropical spotted dolphin.......... WNP..................... 438,064 0.0226 NL
Striped dolphin...................... WNP..................... 570,038 0.0062 NL
Spinner dolphin...................... WNP..................... 1,015,059 0.0031 NL
Rough-toothed dolphin................ WNP..................... 145,729 0.0003 NL
----------------------------------------------------------------------------------------------------------------
\1\ CNP = central north Pacific; ENP = eastern north Pacific; NP = north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

[[Page 850]]

Table 7--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Sea of Japan Operational Area
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status\4\
Km\2\ \3\
----------------------------------------------------------------------------------------------------------------
Fin whale............................ NP...................... 9,250 0.0009 EN
Bryde's whale........................ WNP..................... 20,501 0.0001 NL
Minke whale.......................... WNP ``O'' Stock......... 25,049 0.0004 NL
Minke whale.......................... WNP ``J'' Stock......... 893 0.0002 NL
North Pacific right whale............ WNP..................... 922 < 0.00001 EN
Gray whale (Eschrichtius robustus)... WNP..................... 121 < 0.00001 EN \5\
Sperm whale.......................... NP...................... 102,112 0.0008 EN
Stejneger's beaked whale (Mesoplodon NP...................... 8,000 0.0014 NL
stejnegeri).
Baird's beaked whale................. WNP..................... 8,000 0.0003 NL
Cuvier's beaked whale................ NP...................... 90,725 0.0043 NL
Ginkgo-toothed beaked whale.......... NP...................... 22,799 0.0005 NL
False killer whale................... IA-Pelagic.............. 9,777 0.0027 NL
Melon-headed whale................... WNP..................... 36,770 0.00001 NL
Short-finned pilot whale............. WNP..................... 53,608 0.0014 NL
Risso's dolphin...................... WNP..................... 83,289 0.0073 NL
Common dolphin....................... WNP..................... 3,286,163 0.0860 NL
Bottlenose dolphin................... IA...................... 105,138 0.0009 NL
Pantropical spotted dolphin.......... WNP..................... 219,032 0.0137 NL
Spinner dolphin...................... WNP..................... 1,015,059 0.00001 NL
Pacific white-sided dolphin.......... WNP..................... 931,000 0.0030 NL
Dall's porpoise (Phocoenoides dalli). SOJ..................... 76,720 0.0520 NL
----------------------------------------------------------------------------------------------------------------
\1\ IA = Inshore Archipelago; NP = north Pacific; SOJ = Sea of Japan; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.
\5\ Only the western Pacific population of gray whale is endangered under the ESA.

Table 8--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the East China Sea Operational Area
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Fin whale............................ ECS..................... 500 0.0002 EN
Bryde's whale........................ WNP..................... 20,501 0.0006 NL
Minke whale.......................... WNP ``O'' Stock......... 25,049 0.0044 NL
Minke whale.......................... WNP ``J'' Stock......... 893 0.0018 NL
North Pacific right whale............ WNP..................... 922 < 0.00001 EN
Gray whale........................... WNP..................... 121 < 0.00001 EN \5\
Sperm whale.......................... NP...................... 102,112 0.0012 EN
Pygmy sperm and Dwarf sperm whale.... NP...................... 350,553 0.0031 NL
Cuvier's beaked whale................ NP...................... 90,725 0.0062 NL
Blainville's beaked whale............ NP...................... 8,032 0.0012 NL
Ginkgo-toothed beaked whale.......... NP...................... 22,799 0.0005 NL
False killer whale................... IA-Pelagic.............. 9,777 0.0011 NL
Pygmy killer whale................... WNP..................... 30,214 0.0001 NL
Melon-headed whale................... WNP..................... 36,770 0.0043 NL
Short-finned pilot whale............. WNP..................... 53,608 0.0016 NL
Risso's dolphin...................... WNP..................... 83,289 0.0106 NL
Common dolphin....................... WNP..................... 3,286,163 0.0461 NL
Fraser's dolphin..................... WNP..................... 220,789 0.0040 NL
Bottlenose dolphin................... IA...................... 105,138 0.0146 NL
Pantropical spotted dolphin.......... WNP..................... 219,032 0.0137 NL
Striped dolphin...................... WNP..................... 570,038 0.0164 NL
Spinner dolphin...................... WNP..................... 1,015,059 0.0031 NL
Pacific white-sided dolphin.......... WNP..................... 931,000 0.0028 NL
Rough-toothed dolphin................ WNP..................... 145,729 0.0059 NL
----------------------------------------------------------------------------------------------------------------
\1\ ECS = East China Sea; IA = Inshore Archipelago; NP = north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.
\5\ Only the western Pacific population of gray whale is endangered under the ESA.

[[Page 851]]

Table 9--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the South China Sea Operational Area
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Fin whale............................ WNP..................... 9,250 0.0002 EN
Bryde's whale........................ WNP..................... 20,501 0.0006 NL
Minke whale.......................... WNP ``O'' Stock......... 25,049 0.0033 NL
North Pacific right whale............ WNP..................... 922 < 0.00001 EN
Gray whale........................... WNP..................... 121 < 0.0001 EN \5\
Sperm whale.......................... NP...................... 102,112 0.0012 EN
Pygmy sperm and Dwarf sperm whale.... NP...................... 350,553 0.0017 NL
Cuvier's beaked whale................ NP...................... 90,725 0.0003 NL
Blainville's beaked whale............ NP...................... 8,032 0.0005 NL
Ginkgo-toothed beaked whale.......... NP...................... 22,799 0.0005 NL
False killer whale................... IA-Pelagic.............. 9,777 0.0011 NL
Pygmy killer whale................... WNP..................... 30,214 0.0001 NL
Melon-headed whale................... WNP..................... 36,770 0.0043 NL
Short-finned pilot whale............. WNP..................... 53,608 0.0016 NL
Risso's dolphin...................... WNP..................... 83,289 0.0106 NL
Common dolphin....................... WNP..................... 3,286,163 0.0461 NL
Fraser's dolphin..................... WNP..................... 220,789 0.0040 NL
Bottlenose dolphin................... IA...................... 105,138 0.0146 NL
Pantropical spotted dolphin.......... WNP..................... 219,032 0.0137 NL
Striped dolphin...................... WNP..................... 570,038 0.0164 NL
Spinner dolphin...................... WNP..................... 1,015,059 0.3140 NL
Rough-toothed dolphin................ WNP..................... 145,729 0.0040 NL
----------------------------------------------------------------------------------------------------------------
\1\ IA = Inshore Archipelago; NP = north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.
\5\ Only the western Pacific population of gray whale is endangered under the ESA.

Table 10--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Operational Area Offshore Japan (25[deg] to 40[deg] N)
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Blue whale........................... NP...................... 9,250 0.0003 EN
Fin whale............................ NP...................... 9,250 0.0001 EN
Sei whale............................ NP...................... 37,000 0.0003 EN
Bryde's whale........................ WNP..................... 20,501 0.0004 NL
Minke whale.......................... WNP ``O'' Stock......... 25,049 0.0003 NL
Sperm whale.......................... NP...................... 102,112 0.0003 EN
Pygmy sperm and Dwarf sperm whale.... NP...................... 350,553 0.0049 NL
Baird's beaked whale................. WNP..................... 8,000 0.0001 NL
Cuvier's beaked whale................ NP...................... 90,725 0.0017 NL
Mesoplodon spp....................... NP...................... 22,799 0.0005 NL
False killer whale................... WNP-Pelagic............. 16,668 0.0036 NL
Pygmy killer whale................... WNP..................... 30,214 0.0001 NL
Melon-headed whale................... WNP..................... 36,770 0.0012 NL
Short-finned pilot whale............. WNP..................... 53,608 0.0001 NL
Risso's dolphin...................... WNP..................... 83,289 0.0010 NL
Common dolphin....................... WNP..................... 3,286,163 0.0863 NL
Bottlenose dolphin................... WNP..................... 168,791 0.0005 NL
Pantropical spotted dolphin.......... WNP..................... 438,064 0.0181 NL
Striped dolphin...................... WNP..................... 570,038 0.0500 NL
Spinner dolphin...................... WNP..................... 1,015,059 0.00001 NL
Pacific white-sided dolphin.......... WNP..................... 67,769 0.0048 NL
Rough-toothed dolphin................ WNP..................... 145,729 0.0003 NL
Hawaiian monk seal................... Hawaii.................. 1,129 < 0.00001 EN
(Monachus schauinslandi).............
----------------------------------------------------------------------------------------------------------------
\1\ NP = north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

[[Page 852]]

Table 11--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Operational Area Offshore Japan (10[deg] to 25[deg] N)
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Bryde's whale........................ WNP..................... 20,501 0.0004 NL
Sperm whale.......................... NP...................... 102,112 0.0004 EN
Pygmy sperm and Dwarf sperm whale.... NP...................... 350,553 0.0009 NL
Cuvier's beaked whale................ NP...................... 90,725 0.0017 NL
False killer whale................... WNP-Pelagic............. 16,668 0.0021 NL
Melon-headed whale................... WNP..................... 36,770 0.0012 NL
Short-finned pilot whale............. WNP..................... 53,608 0.0009 NL
Risso's dolphin...................... WNP..................... 83,289 0.0026 NL
Common dolphin....................... WNP..................... 3,286,163 0.0863 NL
Bottlenose dolphin................... WNP..................... 168,791 0.0007 NL
Pantropical spotted dolphin.......... WNP..................... 438,064 0.0226 NL
Striped dolphin...................... WNP..................... 570,038 0.0110 NL
Spinner dolphin...................... WNP..................... 1,015,059 0.0031 NL
Rough-toothed dolphin................ WNP..................... 145,729 0.0003 NL
----------------------------------------------------------------------------------------------------------------
\1\ NP = north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 12--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Northern Hawaii Operational Area
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Blue whale........................... WNP..................... 1,548 0.0002 EN
Fin whale............................ Hawaii.................. 2,099 0.0007 EN
Bryde's whale........................ Hawaii.................. 469 0.0002 NL
Minke whale.......................... WNP..................... 25,000 0.0002 NL
Humpback whale....................... Hawaii.................. 10,103 < 0.0001 EN
Sperm whale.......................... CNP..................... 6,919 0.0028 EN
Pygmy sperm and Dwarf sperm whale.... Hawaii.................. 24,657 0.0101 NL
Cuvier's beaked whale................ Hawaii.................. 15,242 0.0062 NL
Blainville's beaked whale............ Hawaii.................. 2,872 0.0012 NL
Longman's beaked whale............... Hawaii.................. 1,007 0.0004 NL
Killer whale......................... Hawaii.................. 349 0.0001 NL
False killer whale................... Hawaii-Pelagic.......... 484 0.0002 NL
Pygmy killer whale................... Hawaii.................. 956 0.0004 NL
Melon-headed whale................... Hawaii.................. 2,950 0.0012 NL
Short-finned pilot whale............. Hawaii.................. 8,870 0.0036 NL
Risso's dolphin...................... Hawaii.................. 2,372 0.0010 NL
Fraser's dolphin..................... Hawaii.................. 10,226 0.0042 NL
Bottlenose dolphin................... Hawaii.................. 3,215 0.0013 NL
Pantropical spotted dolphin.......... Hawaii.................. 8,978 0.0037 NL
Striped dolphin...................... Hawaii.................. 13,143 0.0054 NL
Spinner dolphin...................... Hawaii.................. 3,351 0.0014 NL
Rough-toothed dolphin................ Hawaii.................. 8,709 0.0036 NL
Hawaiian monk seal................... Hawaii.................. 1,129 < 0.0001 EN
----------------------------------------------------------------------------------------------------------------
\1\ CNP = central north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 13--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Southern Hawaii Operational Area
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Blue whale........................... WNP..................... 1,548 0.0002 EN
Fin whale............................ Hawaii.................. 2,099 0.0007 EN
Bryde's whale........................ Hawaii.................. 469 0.0002 NL
Minke whale.......................... Hawaii.................. 25,000 0.0002 NL
Humpback whale....................... Hawaii.................. 10,103 0.0008 EN
Sperm whale.......................... CNP..................... 6,919 0.0028 EN
Pygmy sperm and Dwarf sperm whale.... Hawaii.................. 24,657 0.0101 NL

[[Page 853]]

Cuvier's beaked whale................ Hawaii.................. 15,242 0.0062 NL
Blainville's beaked whale............ Hawaii.................. 2,872 0.0012 NL
Longman's beaked whale............... Hawaii.................. 1,007 0.0004 NL
Killer whale......................... Hawaii.................. 349 0.0001 NL
False killer whale................... Hawaii-Pelagic.......... 484 0.0002 NL
Pygmy killer whale................... Hawaii.................. 956 0.0004 NL
Melon-headed whale................... Hawaii.................. 2,950 0.0012 NL
Short-finned pilot whale............. Hawaii.................. 8,870 0.0036 NL
Risso's dolphin...................... Hawaii.................. 2,372 0.0010 NL
Fraser's dolphin..................... Hawaii.................. 10,226 0.0042 NL
Bottlenose dolphin................... Hawaii.................. 3,215 0.0013 NL
Pantropical spotted dolphin.......... Hawaii.................. 8,978 0.0037 NL
Striped dolphin...................... Hawaii.................. 13,143 0.0054 NL
Spinner dolphin...................... Hawaii.................. 3,351 0.0014 NL
Rough-toothed dolphin................ Hawaii.................. 8,709 0.0036 NL
Hawaiian monk seal................... Hawaii.................. 1,129 < 0.0001 EN
----------------------------------------------------------------------------------------------------------------
\1\ CNP = central north Pacific; WNP = western north Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 14--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Operational Area Offshore Southern California (SOCAL OPAREA)
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Blue whale........................... ENP..................... 2,842 0.0014 EN
Fin whale............................ CA/OR/WA................ 2,099 0.0018 EN
Sei whale............................ ENP..................... 98 0.0001 EN
Bryde's whale........................ ENP..................... 13,000 0.00001 NL
Northern minke whale................. CA/OR/WA................ 823 0.0007 NL
Humpback whale....................... CA/OR/WA................ 942 0.0008 EN
Gray whale........................... ENP..................... 18,813 0.051 EN \5\
Sperm whale.......................... CA/OR/WA................ 1,934 0.0017 EN
Pygmy sperm whale.................... CA/OR/WA................ 1,237 0.0011 NL
Stejneger's beaked whale............. CA/OR/WA................ 1,177 0.0010 NL
Baird's beaked whale................. CA/OR/WA................ 1,005 0.0009 NL
Cuvier's beaked whale................ CA/OR/WA................ 4,342 0.0038 NL
Blainville's beaked whale............ CA/OR/WA................ 1,177 0.0010 NL
Ginkgo-toothed beaked whale.......... CA/OR/WA................ 1,177 0.0010 NL
Hubbs beaked whale................... CA/OR/WA................ 1,177 0.0010 NL
Longman's beaked whale............... Hawaii.................. 1,177 0.0010 NL
Perrin's beaked whale (Mesoplodon CA/OR/WA................ 1,177 0.0010 NL
perrini).
Pygmy beaked whale (Mesoplodon CA/OR/WA................ 1,177 0.0010 NL
peruvianus).
Killer whale (offshore).............. ENP..................... 810 0.0007 NL
Short-finned pilot whale............. CA/OR/WA................ 350 0.0003 NL
Risso's dolphin...................... CA/OR/WA................ 11,910 0.0105 NL
Long-beaked common dolphin (Delphinus CA/OR/WA................ 21,902 0.0192 NL
capensis).
Short-beaked common dolphin CA/OR/WA................ 352,069 0.3094 NL
(Delphinus delphis).
Bottlenose dolphin (offshore)........ CA/OR/WA................ 2,026 0.0018 NL
Striped dolphin...................... CA/OR/WA................ 18,976 0.0167 NL
Pacific white-sided dolphin.......... CA/OR/WA................ 23,817 0.0209 NL
Northern right whale dolphin CA/OR/WA................ 11,097 0.0098 NL
(Lissodelphis borealis).
Dall's porpoise...................... CA/OR/WA................ 85,955 0.0753 NL
Guadalupe fur seal (Arctocephalus Mexico.................. 7,408 0.007 NL
townsendi).
Northern fur seal (Callorhinus SMI..................... 9,424 0 NL
ursinus).
California sea lion (Zalophus California.............. 238,000 0.54 NL
californianus).
California sea lion.................. California.............. 238,000 0 NL
Harbor seal (Phoca vitulina)......... California.............. 34,233 0.0095 NL
Northern elephant seal (Mirounga CA-Breeding............. 124,000 0.0045 NL
angustirostris).
Northern elephant seal............... CA-Breeding............. 124,000 0 NL
----------------------------------------------------------------------------------------------------------------
\1\ CA/OR/WA = California, Oregon, and Washington; ENP = eastern north Pacific; SMI = San Miguel Island.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.
\5\ Only the western Pacific population of gray whale is endangered under the ESA.

[[Page 854]]

Table 15--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Northwestern Atlantic Operational Area Off Florida (JAX OPAREA)
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Humpback whale....................... WNA..................... 11,570 0.0006 EN
North Atlantic right whale (on shelf) WNA..................... 438 0.0012 EN
Sperm whale (on shelf)............... WNA..................... 4,804 0 EN
Sperm whale (off shelf).............. WNA..................... 4,804 0.0005 EN
Pygmy sperm and Dwarf sperm whale.... WNA..................... 580 0.0010 NL
Beaked whales (on shelf)............. WNA..................... 3,513 0 NL
Beaked whales (off shelf)............ WNA..................... 3,513 0.0006 NL
Cuvier's beaked whale................ WNA..................... 3,513 0.0006 NL
Blainville's beaked whale............ WNA..................... 3,513 0.0006 NL
Gervais' beaked whale (Mesoplodon WNA..................... 3,513 0.0006 NL
europaeus).
Sowerby's beaked whale (Mesoplodon WNA..................... 3,513 0.0006 NL
bidens).
True's beaked whale (Mesoplodon WNA..................... 3,513 0.0006 NL
mirus).
Short-finned pilot whale (on shelf).. WNA..................... 31,139 0.00004 NL
Short-finned pilot whale (off shelf). WNA..................... 31,139 0.0271 NL
Risso's dolphin (on shelf)........... WNA..................... 20,479 0.0009 NL
Risso's dolphin (off shelf).......... WNA..................... 20,479 0.0181 NL
Common dolphin....................... WNA..................... 120,743 0.00002 NL
Bottlenose dolphin (on shelf)........ WNA..................... 81,588 0.2132 NL
Bottlenose dolphin (off shelf)....... WNA..................... 81,588 0.1163 NL
Pantropical spotted dolphin.......... WNA..................... 12,747 0.0223 NL
Striped dolphin...................... WNA..................... 94,462 0.00003 NL
Atlantic spotted dolphin (on shelf) WNA..................... 50,978 0.4435 NL
(Stenella frontalis).
Atlantic spotted dolphin (off shelf). WNA..................... 50,978 0.0041 NL
Clymene dolphin (Stenella clymene)... WNA..................... 6,086 0.0106 NL
Rough-toothed dolphin................ WNA..................... 274 0.0005 NL
----------------------------------------------------------------------------------------------------------------
\1\ WNA = western north Atlantic.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 16--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Operational Area in the Northeastern Atlantic Off the United Kingdom.
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Blue whale........................... ENA..................... 100 0.00001 EN
Fin whale............................ ENA..................... 10,369 0.0031 EN
Sei whale............................ ENA..................... 14,152 0.0113 EN
Northern minke whale................. ENA..................... 107,205 0.0068 NL
Humpback whale....................... ENA..................... 4,695 0.0019 EN
Sperm whale.......................... ENA..................... 6,375 0.0049 EN
Pygmy sperm and Dwarf sperm whale.... ENA..................... 580 0.0001 NL
Cuvier's beaked whale................ ENA..................... 3,513 0.0013 NL
Blainville's beaked whale............ ENA..................... 3,513 0.0013 NL
Sowerby's beaked whale............... ENA..................... 3,513 0.0013 NL
Northern bottlenose whale (Hyperodon ENA..................... 5,827 0.0003 NL
ampullatus).
Killer whale......................... ENA..................... 6,618 0.0001 NL
False killer whale................... ENA..................... 484 0.0001 NL
Long-finned pilot whale (Globicephala ENA..................... 778,000 0.0121 NL
melas).
Risso's dolphin...................... ENA..................... 20,479 0.0063 NL
Common dolphin....................... ENA..................... 273,150 0.238 NL
Bottlenose dolphin................... ENA..................... 81,588 0.0094 NL
Striped dolphin...................... ENA..................... 94,462 0.0765 NL
Atlantic white-sided dolphin ENA..................... 11,760 0.0027 NL
(Lagenorhynchus acutus).
White-beaked dolphin (Lagenorhynchus ENA..................... 11,760 0.0027 NL
albirostris).
Harbor porpoise (Phocoena phocoena).. ENA..................... 341,366 0.2299 NL
Harbor seal (Phoca vitulina)......... Ireland/Scotland........ 23,500 0.0230 NL
Gray seal (Halichoerus grypus)....... ENA..................... 113,300 0.027 NL
----------------------------------------------------------------------------------------------------------------
\1\ ENA = eastern north Atlantic.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

[[Page 855]]

Table 17--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Operational Area in the Western Mediterranean Sea and the Ligurian Sea
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (Animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Fin whale............................ MED..................... 3,583 0.004 EN
Sperm whale.......................... WMED.................... 6,375 0.0049 EN
Cuvier's beaked whale................ ENA..................... 3,513 0.0013 NL
Long-finned pilot whale.............. ENA..................... 778,000 0.0121 NL
Risso's dolphin...................... WMED.................... 5,320 0.0075 NL
Common dolphin....................... WMED.................... 19,428 0.0144 NL
Bottlenose dolphin................... WMED.................... 23,304 0.041 NL
Striped dolphin...................... WMED.................... 117,880 0.24 NL
----------------------------------------------------------------------------------------------------------------
\1\ ENA = eastern north Atlantic; MED = Mediterranean; WMED = western Mediterranean.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 18--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Operational Area in the Northern Arabian Sea
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Bryde's whale........................ IND..................... 9,176 0.0001 NL
Humpback whale....................... XAR..................... 200 0.0004 EN
Sperm whale.......................... IND..................... 24,446 0.0125 EN
Dwarf sperm whale.................... IND..................... 10,541 0.0145 NL
Cuvier's beaked whale................ IND..................... 27,272 0.0001 NL
Blainville's beaked whale............ IND..................... 16,867 0.0016 NL
Ginkgo-toothed beaked whale.......... IND..................... 16,867 0.0016 NL
Longman's beaked whale............... IND..................... 16,867 0.0016 NL
False killer whale (pelagic)......... IND..................... 144,188 0.0003 NL
Pygmy killer whale................... IND..................... 22,029 0.0026 NL
Melon-headed whale................... IND..................... 64,600 0.0661 NL
Short-finned pilot whale............. IND..................... 268,751 0.0034 NL
Risso's dolphin...................... IND..................... 452,125 0.0125 NL
Common dolphin....................... IND..................... 1,819,882 0.0265 NL
Bottlenose dolphin................... IND..................... 785,585 0.0164 NL
Pantropical spotted dolphin.......... IND..................... 736,575 0.0127 NL
Striped dolphin...................... IND..................... 674,578 0.0706 NL
Spinner dolphin...................... IND..................... 634,108 0.01 NL
Rough-toothed dolphin................ IND..................... 156,690 0.0081 NL
----------------------------------------------------------------------------------------------------------------
\1\ IND = Indian Ocean; XAR = Stock X Arabian Sea.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 19--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Operational Area in the Andaman Sea Off Myanmar
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Bryde's whale........................ IND..................... 9,176 0.0001 NL
Sperm whale.......................... IND..................... 24,446 0.0125 EN
Dwarf sperm whale.................... IND..................... 10,541 0.0145 NL
Cuvier's beaked whale................ IND..................... 27,272 0.0001 NL
Blainville's beaked whale............ IND..................... 16,867 0.0016 NL
Ginkgo-toothed beaked whale.......... IND..................... 16,867 0.0016 NL
Longman's beaked whale............... IND..................... 16,867 0.0016 NL
Killer whale......................... IND..................... 12,593 0.0001 NL
False killer whale (pelagic)......... IND..................... 144,188 0.0003 NL
Pygmy killer whale................... IND..................... 22,029 0.0026 NL
Melon-headed whale................... IND..................... 64,600 0.0661 NL
Short-finned pilot whale............. IND..................... 268,751 0.0034 NL
Risso's dolphin...................... IND..................... 452,125 0.0125 NL
Common dolphin....................... IND..................... 1,819,882 0.0265 NL
Bottlenose dolphin................... IND..................... 785,585 0.0164 NL
Pantropical spotted dolphin.......... IND..................... 736,575 0.0127 NL
Striped dolphin...................... IND..................... 674,578 0.0706 NL

[[Page 856]]

Spinner dolphin...................... IND..................... 634,108 0.01 NL
Rough-toothed dolphin................ IND..................... 156,690 0.0081 NL
----------------------------------------------------------------------------------------------------------------
\1\ IND = Indian Ocean.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 20--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Panama Canal Operational Area (West Approach)
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Blue whale........................... ENP..................... 2,842 0.0001 EN
Bryde's whale........................ ETP..................... 13,000 0.0003 NL
Humpback whale....................... ENP..................... 1,391 0.0004 EN
Sperm whale.......................... ETP..................... 22,700 0.0047 EN
Dwarf sperm whale.................... ETP..................... 11,200 0.0145 NL
Cuvier's beaked whale................ ETP..................... 20,000 0.0025 NL
Blainville's beaked whale............ ETP..................... 25,300 0.0013 NL
Ginkgo-toothed beaked whale.......... ETP..................... 25,300 0.0016 NL
Longman's beaked whale............... ETP..................... 25,300 0.0003 NL
Pygmy beaked whale (Mesoplodon ETP..................... 25,300 0.0016 NL
peruvianus).
Killer whale......................... ETP..................... 8,500 0.0002 NL
False killer whale (pelagic)......... ETP..................... 39,800 0.0004 NL
Pygmy killer whale................... ETP..................... 38,900 0.0014 NL
Melon-headed whale................... ETP..................... 45,400 0.0174 NL
Short-finned pilot whale............. ETP..................... 160,200 0.0058 NL
Risso's dolphin...................... ETP..................... 110,457 0.0161 NL
Common dolphin....................... ETP..................... 3,127,203 0.049 NL
Fraser's dolphin..................... ETP..................... 289,300 0.001 NL
Bottlenose dolphin................... ETP..................... 335,834 0.0157 NL
Pantropical spotted dolphin.......... NEOP.................... 640,000 0.0669 NL
Striped dolphin...................... ETP..................... 964,362 0.1199 NL
Spinner dolphin...................... Eastern................. 450,000 0.007 NL
Rough-toothed dolphin................ ETP..................... 107,633 0.0146 NL
----------------------------------------------------------------------------------------------------------------
\1\ ETP = eastern tropical Pacific; NEOP = northeastern offshore Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

Table 21--Abundance and Density Estimates for the Marine Mammal Species, Species Groups, and Stocks Associated
With the Operational Area Off the Northeastern Australian Coast
----------------------------------------------------------------------------------------------------------------
Density
Species Stock name \1\ Abundance \2\ (animals/ ESA Status \4\
Km\2\) \3\
----------------------------------------------------------------------------------------------------------------
Blue whale........................... WSP..................... 9,250 0.0002 EN
Fin whale............................ WSP..................... 9,250 0.0002 EN
Bryde's whale........................ WSP..................... 22,000 0.0006 NL
Northern minke whale................. WSP..................... 25,000 0.0044 EN
Humpback whale....................... GVEA.................... 3,500 0.0143 EN
Sperm whale.......................... WSP..................... 102,112 0.0029 EN
Pygmy sperm and Dwarf sperm whale.... WSP..................... 350,553 0.0031 NL
Cuvier's beaked whale................ WSP..................... 90,725 0.0054 NL
Blainville's beaked whale............ WSP..................... 8,032 0.0005 NL
Arnoux's beaked whale (Berardius WSP..................... 22,799 0.0005 NL
arnuxii).
Ginkgo-toothed beaked whale.......... WSP..................... 22,799 0.0005 NL
Longman's beaked whale............... WSP..................... 22,799 0.0005 NL
Southern bottlenose whale (Hyperodon WSP..................... 22,799 0.0005 NL
planifrons).
Killer whale......................... WSP..................... 12,256 0.0004 NL
False killer whale (pelagic)......... WSP..................... 16,668 0.0029 NL
Pygmy killer whale................... WSP..................... 30,214 0.0021 NL
Melon-headed whale................... WSP..................... 36,770 0.0012 NL
Globicephala spp..................... WSP..................... 53,608 0.0153 NL
Risso's dolphin...................... WSP..................... 83,289 0.0106 NL

[[Page 857]]

Common dolphin....................... WSP..................... 3,286,163 0.0562 NL
Fraser's dolphin..................... WSP..................... 220,789 0.004 NL
Bottlenose dolphin................... WSP..................... 168,791 0.0146 NL
Pantropical spotted dolphin.......... WSP..................... 438,064 0.0137 NL
Striped dolphin...................... WSP..................... 570,038 0.0329 NL
Spinner dolphin...................... WSP..................... 1,015,059 0.0005 NL
Dusky dolphin (Lagenorhynchus WSP..................... 12,626 0.0002 NL
obscurus).
Rough-toothed dolphin................ WSP..................... 145,729 0.0059 NL
----------------------------------------------------------------------------------------------------------------
\1\ GVEA = group V east Australia; WSP = western south Pacific.
\2\ Refer to Table 5 of the Navy's application for literature references associated with abundance estimates
presented in this table.
\3\ Refer to Table 5 of the Navy's application for literature references associated with density estimates
presented in this table.
\4\ ESA Status: EN = Endangered; T = Threatened; NL = Not Listed.

The Navy provides detailed descriptions of the distribution,
abundance, diving behavior, life history, and hearing vocalization
information for each affected marine mammal species with confirmed or
possible occurrence within SURTASS LFA sonar operational areas in
section 4 (pages 38-97) of the application, which is available online
at http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications).
Although not repeated in this document, NMFS has reviewed these
data, determined them to be the best available scientific information
for the purposes of the proposed rulemaking, and considers this
information part of the administrative record for this action.
Additional information is available in NMFS' Marine Mammal Stock
Assessment Reports, which may be viewed at http://www.nmfs.noaa.gov/pr/sars/species.htm. Also, NMFS refers the public to Table 5 (page 37) of
the Navy's application for literature references associated with
abundance and density estimates presented in these tables.

Brief Background on Sound, Marine Mammal Hearing, and Vocalization

Acoustic Source Specifications

Metrics Used in This Document

This section includes a brief explanation of the sound measurements
frequently used in the discussions of acoustic effects in this
document. Sound pressure is the sound force per unit area and is
usually measured in micropascals ([mu]Pa), where 1 Pascal (Pa) is the
pressure resulting from a force of one newton exerted over an area of
one square meter. Sound pressure level (SPL) is expressed as the ratio
of a measured sound pressure and a reference level. The commonly used
reference pressure level in underwater acoustics is 1 [mu]Pa at 1 m,
and the units for SPLs are decibels (dB) re: 1 [mu]Pa at 1 m. SPL (in
dB) = 20 log (pressure/reference pressure). SPL is an instantaneous
measurement and can be expressed as the peak, the peak-peak (p-p), or
the root mean square (rms). Root mean square, 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 unless otherwise noted. SPL does not take the duration
of a sound into account.

SPL and the Single Ping Equivalent (SPE)

To model potential impacts to marine animals from exposure to
SURTASS LFA sonar sound, the Navy has developed a methodology to
estimate the total exposure of modeled animals exposed to multiple
pings over an extended period of time. The Navy's acoustic model
analyzes the following components: (1) The LFA sonar source modeled as
a point source, with an effective source level (SL) in dB re: 1 [mu]Pa
at 1 m (SPL); (2) a 60-sec duration signal; and (3) a beam pattern that
is correct for the number and spacing of the individual projectors
(source elements). This source model, when combined with the three-
dimensional transmission loss (TL) field generated by the Parabolic
Equation (PE) acoustic propagation model, defines the received level
(RL) (in SPL) sound field surrounding the source for a 60-sec LFA sonar
signal. To estimate the total exposure of animals exposed to multiple
pings, the Navy models the RLs for each modeled location and any
computer-simulated marine mammals (also called animats) within the
location, records the exposure history of each animat, and generates a
single ping equivalent (SPE) value. Thus, the Navy can model the
SURTASS LFA sound field, providing a four-dimensional (position and
time) representation of a sound pressure field within the marine
environment and estimates of an animal's exposure to sound.
Figure 2 shows the Navy calculation that converts SPL values to SPE
values in order to estimate impacts to marine mammals from SURTASS LFA
sonar transmissions. For a more detailed explanation of the SPE
calculations, NMFS refers the public to Appendix C of the Navy's 2011
DSEIS/SOEIS.

[[Page 858]]

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Underwater Sound

An understanding of the basic properties of underwater sound is
necessary to comprehend many of the concepts and analyses presented in
this document.
Sound is a wave of pressure variations propagating through a medium
(for the sonar considered in this proposed rulemaking, the medium is
seawater). 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, it is derived from ratios of pressures; the
standard reference pressure for underwater sound is 1 [mu]Pa at 1 m
(Richardson et al., 1995).
Acousticians have adopted a logarithmic scale for sound
intensities, which is denoted in dB. The logarithmic nature of the
scale means that each 10 dB increase is a ten-fold increase in power
(e.g., 20 dB is a 100-fold increase, 30 dB is a 1,000-fold increase).
Humans perceive a 10-dB increase in noise as a doubling of sound level,
or a 10-dB decrease in noise as a halving of sound level. Sound
pressure level or SPL implies a decibel measure and a reference
pressure that is used as the denominator of the ratio.
Sound frequency is measured in cycles per second, referred to as
Hertz (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 five Hz to harbor porpoise clicks
at 150,000 Hz (150 kilohertz (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 tactical sonars are an example of a
narrowband sound source.

Marine Mammal Hearing

Cetaceans have an auditory anatomy that follows the basic mammalian
pattern, with some changes to adapt to the demands of hearing in the
sea. 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 (i.e., the product of density and sound speed) 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).
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 auditory evoked
potential (AEP) techniques, anatomical modeling, and other data,
Southall et al. (2007) designated ``functional hearing groups'' for
marine mammals and estimated the lower and upper frequencies of
functional hearing (i.e., the frequencies that the species can actually
hear) of these groups. The functional groups and the associated
frequencies are described here (though 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 (LF) cetaceans (13 species of mysticetes):
Southall et al. (2007) estimates that functional hearing occurs between
approximately seven Hz and 22 kHz;
Mid-frequency (MF) cetaceans (32 species of dolphins, six
species of larger toothed whales, and 19 species of beaked and
bottlenose whales): Southall et al. (2007) estimates that functional
hearing occurs between approximately 150 Hz and 160 kHz;
High frequency (HF) cetaceans (eight species of true
porpoises, six species of river dolphins, Kogia, the franciscana, and
four species of cephalorhynchids): Southall et al. (2007) estimates
that functional hearing occurs between approximately 200 Hz and 180
kHz.
Pinnipeds in Water: Southall et al. (2007) estimates that
functional hearing occurs between approximately 75 Hz and 75 kHz, with
the greatest sensitivity between approximately 700 Hz and 20 kHz.

Marine Mammal Functional Hearing Groups and LFA Sonar

Baleen (mysticete) whales (members of the LF functional hearing
group) have inner ears that appear to be specialized for low-frequency
hearing. Conversely, most odontocetes (i.e., sperm whales, dolphins and
porpoises) have inner ears that are specialized to hear mid and high
frequencies. Pinnipeds, which lack the highly specialized active
biosonar systems of odontocetes, have inner ears that are specialized
to hear a broad range of frequencies in water (Southall et al., 2007).
Based on an extensive suite of reported laboratory measurements (DoN,
2001, Ketten, 1997, Southall et al., 2007), the LFA sound source is
below the range of best hearing sensitivity for MF and HF odontocete
and pinnipeds in water hearing specialists (Clark and Southall, 2009).

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Marine Mammal Vocalization

Marine mammal vocalizations often extend both above (higher than 20
kHz) and below (lower than 20 Hz) the range of human hearing (National
Research Council, 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 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. Thus, the ears of small toothed whales are optimized for
receiving high-frequency sound, while baleen whale inner ears are best
suited for low frequencies, including to infrasonic frequencies
(Ketten, 1992; 1997; 1998).
Baleen whale (i.e., mysticete) vocalizations are composed primarily
of frequencies below one 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
mysticetes 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 [mu]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).
Toothed whales (i.e., odontocetes) 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 whales
social vocalizations is concentrated near 10 kHz, with source levels
for whistles as high as 100-180 dB re 1 [mu]Pa at 1 m (Richardson et
al., 1995). No odontocete has been shown audiometrically to have acute
hearing (less than 80 dB re 1 [mu]Pa at 1 m) below 500 Hz (DoN, 2001;
Ketten, 1998). 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 [mu]Pa at 1 m
or greater (Mohl et al., 2000).

Brief Background on the Navy's Assessment of the Potential Impacts on
Marine Mammals

Acoustic Modeling Scenarios. The Navy based their analysis of
potential impacts on marine mammals from SURTASS LFA sonar on
literature review, the Navy's Low Frequency Sound Scientific Research
Program (LFS SRP), and a comprehensive program of underwater acoustical
modeling.
To assess the potential impacts on marine mammals by the SURTASS
LFA sonar source operating at a given site, the Navy must predict the
sound field that a given marine mammal species could be exposed to over
time. This is a multi-part process involving: (1) The ability to
measure or estimate an animal's location in space and time; (2) The
ability to measure or estimate the three-dimensional sound field at
these times and locations; (3) The integration of these two data sets
into the Acoustic Integration Model (AIM) to estimate the total
acoustic exposure for each animal in the modeled population; and (4)
Converting the resultant cumulative exposures (within the post-AIM
analysis) for a modeled population into an estimate of the risk of a
significant disturbance of a biologically important behavior (i.e., a
take estimate for Level B harassment of marine mammals based upon an
estimated percentage of each stock affected by SURTASS LFA sonar
operations) or an assessment of risk in terms of injury of marine
mammals (i.e., a take estimate for Level A harassment of marine mammals
based on a cumulative exposure of greater than or equal to 180-dB SPE).
In the post-AIM analysis, as mentioned in number (4), the Navy
developed a relationship for converting the resultant cumulative
exposures for a modeled population into an estimate of the risk to the
entire population of a significant disruption of a biologically
important behavior and of injury. This process assessed risk in
relation to received level (RL) and repeated exposure. The Navy's risk
continuum is based on the assumption that the threshold of risk is
variable and occurs over a range of conditions rather than at a single
threshold. Taken together, the LFS SRP results, the acoustic
propagation modeling, and the Navy's risk assessment model provide an
estimate of takes of marine mammals.
The Navy modeled acoustic propagation using its standard acoustical
performance prediction transmission loss model-PE version 3.4. The
results of this model are the primary input to the AIM, which the Navy
used to estimate marine mammal sound exposures. AIM integrates
simulated movements (including dive patterns) of marine mammals, a
schedule of SURTASS LFA sonar transmissions, and the predicted sound
field for each transmission to estimate acoustic exposure during a
hypothetical SURTASS LFA sonar operation. Description of the PE and AIM
models, including AIM input parameters for animal movement, diving
behavior, and marine mammal distribution, abundance, and density, are
described in detail in the Navy's application and in the DSEIS/SOEIS
(see Subchapter 4.4 and Appendix C) and are not discussed further in
this document.
For this application for rulemaking, the Navy has used the same
analytical methodology utilized in the first and second five-year rules
and LOAs to provide reasonable and realistic estimates of the potential
effects to marine mammals specific to the

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potential mission areas as presented in the application. Although this
proposed rule uses the same analytical methodology the Navy used for
the 2002-2007 rule, the Navy continuously updates the analysis with new
marine mammal biological data (behavior, distribution, abundance and
density) whenever new information becomes available.
The Navy initially developed 31 acoustic modeling scenarios for the
major ocean regions in the SURTASS LFA sonar FOEIS/EIS (DoN, 2001); 11
acoustic modeling scenarios for the 2007 FSEIS and the 2007 rulemaking
and LOAs; and eight additional sites for the 2011 DSEIS/SOEIS.
In the initial modeling effort for the 2001 FOEIS/EIS, the Navy
selected locations to represent the greatest potential effects for each
of the three major ocean acoustic regimes where SURTASS LFA sonar could
potentially be used. These acoustic regimes were: (1) Deep-water
convergence zone propagation, (2) near surface duct propagation, and
(3) shallow water bottom interaction propagation. The Navy selected
these sites to model the greatest potential for effects from the use of
SURTASS LFA sonar incorporating the following factors: (1) closest
plausible proximity to land (from a SURTASS LFA sonar operations
standpoint), and/or OBIAs for marine mammals most likely to be
affected; (2) acoustic propagation conditions that allow minimum
propagation loss, or transmission loss (TL) (i.e., longest acoustic
transmission ranges); and (3) time of year selected for maximum animal
abundance. These 31 sites presented in the Navy's 2001 FOEIS/EIS
represented the upper bound of impacts (in terms of both possible
acoustic propagation conditions and marine mammal population and
density) that could be expected from operation of the SURTASS LFA sonar
system.
In the 2007 FSEIS, the Navy provided a risk assessment case study
that included nine additional sites based on reasonable and realistic
choices for potential SURTASS LFA sonar testing, training, and
operations during the proposed period of the rulemaking and LOA
application. Subsequent to the publication of the 2007 FSEIS, the Navy
added two additional sites in the waters north and south of the
Hawaiian Islands. The most recent risk assessment analyses provided in
the Navy's application and 2011 DSEIS/SOEIS proves updated modeling for
the 11 sites under the 2007 rulemaking and eight additional sites using
the most up-to-date marine mammal abundance, density, and behavioral
information available. These 19 operating sites are in areas of
potential strategic importance and/or areas of possible naval fleet
exercises.
Overall, the Navy's total effort for underwater acoustic modeling
includes all 50 potential operational sites for SURTASS LFA sonar. The
analysis of the 50 potential sites provides the foundation for the
analysis of potential effects of SURTASS LFA sonar operations on the
overall marine environment.
If the Navy conducts SURTASS LFA sonar operations in an area that
was not acoustically modeled in the 2001 FOEIS/EIS (DoN, 2001), the
2007 FSEIS (DoN, 2007) or the 2011 DSEIS/SOEIS (DoN, 2011), the Navy
states that the potential effects would most likely be less than those
analyzed for the most similar site in the analyses because the modeled
sites represent the upper bound of effects. NMFS concurs with this
approach, as any site not modeled in the Navy's analyses should fall
within or under the modeled bounds of impacts of possible acoustic
propagation conditions and marine mammal densities. The assumptions of
the 2001 FOEIS/EIS (DoN, 2001) and the 2007 FSEIS (DoN, 2007) are still
valid and there are no new data to contradict the conclusions made in
the Navy's documents.
Risk Analysis. To determine the potential impacts that exposure to
LF sound from SURTASS LFA sonar operations could have on marine
mammals, the Navy defined biological risk standards with associated
measurement parameters. The Navy's measurement parameters for
determining exposure were RLs in dB, the pulse repetition interval
(time between pings), and the number of pings received. To address the
potential for accumulation of effects on marine mammals over a seven to
20-day period (i.e., the estimated maximum SURTASS LFA sonar mission
period, allowing for varying RLs and a duty cycle of 20 percent or
less), the Navy developed a function that translates the modeled
history of repeated exposures (as calculated in the AIM) into an
equivalent RL for a single exposure with a comparable risk (as
previously discussed in the SPL and the Single Ping Equivalent (SPE)
section). Based upon the best available information, NMFS believes that
the Navy's assumptions are still valid and there are no new data to
contradict the conclusions made by the Navy's risk analysis. NMFS
refers the reader to Section 6.4.3 of the Navy's application and
Appendix C of the 2011 DSEIS/SOEIS for more detailed information on the
Navy's risk assessment approach.

Potential Effects of the Specified Activity on Marine Mammals

The Navy has requested authorization for the incidental take of
marine mammals that may result from upcoming training, testing, and
military operations using SURTASS LFA sonar on a maximum of four U.S.
Naval ships in certain areas of the Pacific, Atlantic, and Indian
Oceans and the Mediterranean Sea. In addition to the use of LFA and HF/
M3 sonar, the Navy has analyzed the potential impact of ship strike to
marine mammals from SURTASS LFA sonar operations, and, in consultation
with NMFS as a cooperating agency for the SURTASS LFA sonar 2011 DSEIS/
SOEIS, has determined that take of marine mammals incidental to this
non-acoustic component of the Navy's operations is unlikely and,
therefore, has not requested authorization for take of marine mammals
that might occur incidental to vessel ship strike. In this document,
NMFS analyzes the potential effects on marine mammals from exposure to
LFA and HF/M3 sonar, but also includes some additional analysis of the
potential impacts from vessel operations.
For the purpose of MMPA authorizations, NMFS' effects assessments
serve four primary purposes: (1) Identification of the permissible
methods of taking, meaning: The nature of the take (e.g., resulting
from anthropogenic noise versus from ship strike, etc.); the regulatory
level of take (i.e., mortality versus Level A or Level B harassment)
and the estimated amount of take; (2) Informing the prescription of
means of effecting the least practicable adverse impact on such species
or stock and its habitat (i.e., mitigation); (3) Supporting the
determination of whether the specified activity will have a negligible
impact on the affected species or stocks of marine mammals (based on
the likelihood that the activity will adversely affect the species or
stock through effects on annual rates of recruitment or survival); and
(4) Determining whether the specified activity will have an unmitigable
adverse impact on the availability of the species or stock(s) for
subsistence uses.
NMFS' analysis of potential impacts from SURTASS LFA operations
including lethal responses, physical trauma, sensory impairment
(permanent and temporary threshold shifts and acoustic masking),
physiological responses (particularly stress responses), and behavioral
disturbance

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is outlined below this section. NMFS will focus qualitatively on the
different ways that SURTASS LFA sonar operations may affect marine
mammals (some of which may not classify as take). Then, in the
Estimated Take of Marine Mammals Section, NMFS will relate the
potential effects to marine mammals from SURTASS LFA sonar operations
to the MMPA definitions of take, including Level A and Level B
Harassment, and attempt to quantify those effects.
The potential effects to marine mammals described in the following
sections do not take into consideration the proposed monitoring and
mitigation measures described later in this document (see the Proposed
Mitigation section which, as noted, are designed to effect the least
practicable adverse impact on affected marine mammals species and
stocks.

Potential Effects of Exposure to SURTASS LFA Sonar Operations

Based on the literature, the potential effects of sound from the
proposed activities associated with SURTASS LFA sonar might include one
or more of the following: Behavioral changes, masking, non-auditory
injury, and noise-induced loss of hearing sensitivity (more commonly
called ``threshold shift''). Separately, an animal's behavioral
reaction to an acoustic exposure might lead to physiological effects
that might ultimately lead to injury or death. NMFS discusses this
potential effect later in the Stranding section.
The effects of underwater noise on marine mammals are highly
variable, and one can categorize the effects as follows (Richardson et
al., 1995; Nowacek et al., 2007; Southall et al., 2007):
(1) The noise may be too weak to be heard at the location of the
animal (i.e., lower than the prevailing ambient noise level, the
hearing threshold of the animal at relevant frequencies, or both);
(2) The noise may be audible but not strong enough to elicit any
overt behavioral response;
(3) The noise may elicit behavioral reactions of variable
conspicuousness and variable relevance to the well-being of the animal;
these can range from temporary alert responses to active avoidance
reactions such as vacating an area at least until the noise event
ceases but potentially for longer periods of time;
(4) Upon repeated exposure, a marine mammal may exhibit diminishing
responsiveness (habituation), or disturbance effects may persist; the
latter is most likely with sounds that are highly variable in
characteristics, infrequent, and unpredictable in occurrence, and
associated with situations that the animal perceives as a threat;
(5) Any anthropogenic (human-made) noise that is strong enough to
be heard has the potential to reduce (mask) the ability of a marine
mammal to hear natural sounds at similar frequencies, including calls
from conspecifics (i.e., an organism of the same species), and
underwater environmental sounds such as surf noise;
(6) If mammals remain in an area because it is important for
feeding, breeding, or some other biologically important purpose even
though there is a chronic exposure to noise, it is possible that there
could be noise-induced physiological stress; this might in turn have
negative effects on the well-being or reproduction of the animals
involved; and
(7) Very strong sounds have the potential to cause temporary or
permanent reduction in hearing sensitivity, also known as threshold
shift. In terrestrial mammals and presumably marine mammals, received
sound levels must far exceed the animal's hearing threshold for there
to be any temporary threshold shift (TTS) in its hearing ability. For
transient sounds, the sound level necessary to cause TTS is inversely
related to the duration of the sound. Received sound levels must be
even higher for there to be risk of permanent hearing impairment. In
addition, intense acoustic or explosive events (not relevant for this
proposed activity) may cause trauma to tissues associated with organs
vital for hearing, sound production, respiration and other functions.
This trauma may include minor to severe hemorrhage.

Direct Physiological Effects

Threshold Shift (Noise-Induced Loss of Hearing)

When animals exhibit reduced hearing sensitivity within their
auditory range (i.e., sounds must be louder for an animal to detect
them) following exposure to a sufficiently intense sound or a less
intense sound for a sufficient duration, it is referred to as a noise-
induced threshold shift (TS). An animal can experience a temporary
threshold shift (TTS) and/or permanent threshold shift (PTS). TTS can
last from minutes or hours to days (i.e., there is recovery back to
baseline/pre-exposure levels), can occur within a specific frequency
range (i.e., an animal might only have a temporary loss of hearing
sensitivity within a limited frequency band of its auditory range), and
can be of varying amounts (for example, an animal's hearing sensitivity
might be reduced by only six dB or reduced by 30 dB). PTS is permanent
(i.e., there is incomplete recovery back to baseline/pre-exposure
levels), but also can 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 TSs: 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 (at least in terrestrial mammals), displacement of certain
inner ear membranes, increased blood flow, and post-stimulatory
reduction in both efferent and sensory neural output (Southall et al.,
2007). As amplitude and duration of sound exposure increase, so,
generally, does the amount of TS, along with the recovery time. Human
non-impulsive noise exposure guidelines are based on the assumption
that exposures of equal energy (the same Sound Exposure Level (SEL))
producing equal amounts of hearing impairment regardless of how the
sound energy is distributed in time (NIOSH, 1998). Until recently,
previous marine mammal TTS studies have also generally supported this
equal energy relationship (Southall et al., 2007). The amplitude,
duration, frequency, temporal pattern, and energy distribution of sound
exposure all affect the amount of associated TS and the frequency range
in which it occurs. Three studies, two by Mooney et al. (2009a, 2009b)
on a single bottlenose dolphin either exposed to playbacks of Navy MF
active sonar or octave-band noise (4-8 kHz) and one by Kastak et al.
(2007) on a single California sea lion exposed to airborne octave-band
noise (centered at 2.5 kHz), concluded that for all noise exposure
situations the equal energy relationship may not be the best indicator
to predict TTS onset levels. All three of these studies highlight the
inherent complexity of predicting TTS onset in marine mammals, as well
as the importance of considering exposure duration when assessing
potential impacts. Generally, with sound exposures of equal energy,
those that were quieter (lower sound pressure level (SPL)) with longer
duration were found to induce TTS onset at lower levels than those of
louder (higher SPL) and shorter duration. For intermittent sounds, less
TS will occur than from a continuous exposure with the same energy
(some recovery can occur between intermittent exposures) (Kryter et
al., 1966; Ward, 1997; Mooney et al.

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2009a, 2009b; Finneran et al. 2010). For example, one short but loud
(higher SPL) sound exposure may induce the same impairment as one
longer but softer (lower SPL) 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,
very prolonged or repeated exposure to sound 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;
Lonsbury-Martin et al. 1987) (although in the case of SURTASS LFA,
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 cetaceans, published data on the onset of TTS are
limited to the captive bottlenose dolphin, beluga, harbor porpoise, and
Yangtze finless porpoise (Finneran et al., 2000, 2002b, 2005a, 2007,
2010a, 2010b; Schlundt et al., 2000; Nachtigall et al., 2003, 2004;
Mooney et al., 2009a, 2009b; Lucke et al., 2009; Finneran and Schlundt,
2010; Popov et al., 2011). For pinnipeds in water, data are limited to
Kastak et al.'s (1999, 2005) measurement of TTS in one captive harbor
seal, one captive elephant seal, and one captive California sea lion
(Finneran et al., 2003 tried to induce TTS in two California sea lions
but could not).
Marine mammal hearing plays a critical role in communication with
conspecifics and in 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 takes place
during a time when the animal is traveling through the open ocean,
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 a time when communication is critical for successful
mother/calf interactions could have more serious impacts if it were in
the same frequency band as the necessary vocalizations and of a
severity that impeded communication. The fact that animals exposed to
levels and durations of sound that would be expected to result in this
physiological response would also be expected to have behavioral
responses of a comparatively more severe or sustained nature is
potentially more significant than simple existence of a TTS.
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 than TTS 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. There is no empirical evidence that exposure to SURTASS LFA sonar
can cause PTS in any marine mammals; instead the possibility of PTS has
been inferred from studies of TTS on captive marine mammals (see
Richardson et al., 1995).

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
(e.g., beaked whales) are theoretically predicted to induce greater
supersaturation (Houser et al., 2001b), although recent preliminary
empirical data suggests that there is no increase in blood nitrogen
levels or formation of bubbles in diving bottlenose dolphins (Houser,
2009). 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 the SURTASS LFA sonar
pings 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) speculates 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
(rectified diffusion and decompression sickness) 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; Cox et al., 2006; Rommel et al., 2006). 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 exposure levels and tissue saturation levels that are
highly improbable to occur in diving marine mammals. To date, energy
levels predicted to cause in vivo bubble

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formations 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 (Rommel et al., 2006). 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 MF/HF active sonar exposures.
In 2009, Hooker et al. (2009) tested two mathematical models to
predict blood and tissue tension N2 (PN2) using field data
from three beaked whale species: Northern bottlenose whales, Cuvier's
beaked whales, and Blainville's beaked whales. The researchers aimed to
determine if physiology (body mass, diving lung volume, and dive
response) or dive behavior (dive depth and duration, changes in ascent
rate, and diel behavior) would lead to differences in PN2
levels and thereby decompression sickness risk between species.
In their study, they compared results for previously published time
depth recorder data (Hooker and Baird, 1999; Baird et al., 2006, 2008)
from Cuvier's beaked whale, Blainville's beaked whale, and northern
bottlenose whale. They reported that diving lung volume and extent of
the dive response had a large effect on end-dive PN2. Also,
results showed that dive profiles had a larger influence on end-dive
PN2 than body mass differences between species. Despite diel
changes (i.e., variation that occurs regularly every day or most days)
in dive behavior, PN2 levels showed no consistent trend.
Model output suggested that all three species live with tissue
PN2 levels that would cause a significant proportion of
decompression sickness cases in terrestrial mammals. The authors
concluded that the dive behavior of Cuvier's beaked whale was different
from both Blainville's beaked whale, and northern bottlenose whale, and
resulted in higher predicted tissue and blood N2 levels (Hooker et al.,
2009) and suggested that the prevalence of Cuvier's beaked whales
stranding after naval sonar exercises could be explained by either a
higher abundance of this species in the affected areas or by possible
species differences in behavior and/or physiology related to MF active
sonar (Hooker et al., 2009).
The hypotheses for gas bubble formation related to beaked whale
strandings is that beaked whales potentially have strong avoidance
responses to MF active sonars because they sound similar to their main
predator, the killer whale (Cox et al., 2006; Southall et al., 2007;
Zimmer and Tyack, 2007; Baird et al.,2008; Hooker et al., 2009).
Because SURTASS LFA sonar transmissions are lower in frequency (less
than 500 Hz) and dissimilar in characteristics from those of marine
mammal predators, or MF active sonars the SURTASS LFA sonar
transmissions are not expected to cause gas bubble formation or beaked
whale strandings. Further investigation is needed to further assess the
potential validity of these hypotheses.

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 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 as, 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, the detection of frequencies above those of the
masking stimulus decreases. 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 that low-frequency sounds 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 higher
frequencies these cetaceans use to echolocate, but not at the low-to-
moderate frequencies they use to communicate (Zaitseva et al., 1980). A
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. Holt et al. (2009) measured killer
whale call source levels and background noise levels in the one to 40
kHz band and reported that the whales increased their call source
levels by one dB SPL for every one dB SPL increase in background noise
level. Similarly, another study on St. Lawrence River belugas reported
a similar rate of increase in vocalization activity in response to
passing vessels (Scheifele et al., 2005).
Parks et al. (2007) provided evidence of behavioral changes in the
acoustic behaviors of the endangered North Atlantic right whale, and
the South Atlantic right whale, and suggested that these were
correlated to increased underwater noise levels. The study indicated
that right whales might shift the frequency band of their calls to
compensate for increased in-band background noise. The significance of
their result is the indication of potential species-wide behavioral
change in response to gradual, chronic increases in underwater ambient
noise. Di Iorio and Clark (2010) showed that blue whale calling rates
vary in association with seismic sparker survey activity, with whales
calling more on days with survey than on days without surveys. They
suggested that the whales called more during seismic survey periods as
a way to compensate for the elevated noise conditions.
As mentioned previously, the functional hearing ranges of
mysticetes overlap with the frequencies of the SURTASS LFA sonar
sources used in the Navy's training and testing, as well as during
military operations. The closer the characteristics of the masking
signal to the signal of interest, the more likely masking is to occur.
The masking effects of the SURTASS LFA sonar signal are

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expected to be limited for a number of reasons. First, the frequency
range (bandwidth) of the system is limited to approximately 30 Hz, and
the instantaneous bandwidth at any given time of the signal is small,
on the order of 10 Hz. Second, the average duty cycle is always less
than 20 percent and, based on past LFA sonar operational parameters
(2003 to 2012), is nominally 7.5 to 10 percent. Third, given the
average maximum pulse length (60 sec), and the fact that the signals
vary and do not remain at a single frequency for more than 10 sec,
SURTASS LFA sonar is not likely to cause significant masking. The Navy
provided an analysis of marine mammal hearing and masking in Subchapter
4.6.1.2 of the 2007 FSEIS and 4.2.5 in the 2011 DSEIS/SOEIS. In other
words, the LFA sonar transmissions are coherent, narrow bandwidth
signals of six to 100 sec in length followed by a quiet period of six
to 15 minutes. Therefore, the effect of masking will be limited because
animals that use this frequency range typically use broader bandwidth
signals. As a result, the chances of an LFA sonar sound actually
overlapping whale calls at levels that would interfere with their
detection and recognition would be extremely low.

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 they drop 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 which 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
communications 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 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 or sympathetic nervous 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 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
functions, which impair 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 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 involve 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

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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).
There is limited information on the physiological responses of
marine mammals to anthropogenic sound exposure, as most observations
have been limited to short-term behavioral responses, which included
cessation of feeding, resting, or social interactions. Despite the
dearth of information on stress responses for marine mammals exposed to
anthropogenic sounds, studies of other marine animals and terrestrial
animals 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 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 (e.g., 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)
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 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), NMFS also assumes that stress responses could
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 (in both nature and magnitude) an acoustic event. An
animal's prior experience with a sound or sound source affects 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
the 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, but is
not limited to, no response or any of the following observable
responses: increased alertness; orientation or attraction to a sound
source; vocal modifications; cessation of feeding; cessation of social
interaction; alteration of movement or diving behavior; avoidance;
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 (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
subsections provide examples of behavioral responses that provide an
idea of the variability in behavioral responses that would be expected
given the different 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.
Alteration of Diving or Movement. 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, a reaction, 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

[[Page 866]]

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 the speed of approach, all 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
varied nature of behavioral effects and consequent difficulty in
defining and predicting them.
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 of western gray 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 SURTASS
LFA sonar demonstrated no responses or change in foraging behavior that
could be attributed to the low-frequency sounds (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 level was 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.
Brownell (2004) reported the behavioral responses of western gray
whales off the northeast coast of Sakhalin Island to sounds produced by
local seismic activities. In 1997, the gray whales responded to seismic
activities by changing their swimming speed and orientation,
respiration rates, and distribution in waters around the seismic
surveys. In 2001, seismic activities were conducted in a known foraging
ground and the whales left the area and moved farther south to the Sea
of Okhotsk. They only returned to the foraging ground several days
after the seismic activities stopped. The potential fitness
consequences of displacing these whales, especially mother-calf pairs
and ``skinny whales,'' outside of their normal feeding area are not
known; however, because gray whales, like other large whales, must gain
enough energy during the summer foraging season to last them the entire
year, sounds or other stimuli that cause them to abandon a foraging
area for several days could disrupt their energetics (i.e., the
measurement of energy flow through an animal, from what goes into an
animal as food (prey) to how the animal converts that energy for
growth, reproduction, maintenance, and metabolism) and force them to
make trade-offs like delaying their migration south, delaying
reproduction, reducing growth, or migrating with reduced energy
reserves.
Social Relationships. Social interactions between mammals can be
affected by noise via the disruption of communication signals or by the
displacement of individuals. Sperm whales responded to military sonar,
apparently from a submarine, by dispersing from social aggregations,
moving away from the sound source, remaining relatively silent, and
becoming difficult to approach (Watkins et al., 1985). In contrast,
sperm whales in the Mediterranean that were exposed to submarine sonar
continued calling (J. Gordon pers. comm. cited in Richardson et al.,
1995). Social disruptions must be considered, however, in context of
the relationships that are affected. While some disruptions may not
have deleterious effects, long-term or repeated disruptions of mother/
calf pairs or interruption of mating behaviors have the potential to
affect the growth and survival or reproductive effort/success of
individuals.
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
United States 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. Avoidance 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. However, longer term displacement is possible and can lead
to changes in abundance or distribution patterns of the species in the
affected region if animals do not become acclimated to the presence of
the chronic 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

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long-term or repetitive/chronic displacement for some dolphin groups
and for manatees has been suggested to result from the presence of
chronic vessel noise (Haviland-Howell et al., 2007; Miksis-Olds et al.,
2007).
In 1998, the Navy conducted a Low Frequency Sonar Scientific
Research Program (LFS SRP) to investigate avoidance behavior of gray
whales to low frequency sound signals. The objective was to determine
whether whales respond more strongly to received levels (RL), sound
gradient, or distance from the source, and to compare whale avoidance
responses to an LF source in the center of the migration corridor
versus in the offshore portion of the migration corridor. A single
source was used to broadcast LFA sonar sounds up to 200 dB. The Navy
reported that the whales showed some avoidance responses when the
source was moored one mile (1.8 km) offshore, in the migration path,
but returned to their migration path when they were a few kilometers
from the source. When the source was moored two miles (3.7 km)
offshore, responses were much less, even when the source level was
increased to 200 dB re: 1 [micro]Pa, to achieve the same RL for most
whales in the middle of the migration corridor. Also, the researchers
noted that the offshore whales did not seem to avoid the louder
offshore source.
Also during the LFS SRP, researchers sighted numerous odontocete
and pinniped species in the vicinity of the sound exposure tests with
LFA sonar. The MF and HF hearing specialists present in the study area
showed no immediately obvious responses or changes in sighting rates as
a function of source conditions. Consequently, the researchers
concluded that none of these species had any obvious behavioral
reaction to LFA signals at received levels similar to those that
produced only minor but short-term behavioral responses in the baleen
whales (i.e., LF hearing specialists) (Clark and Southall, 2009). Thus,
for odontocetes, the chances of injury and/or significant behavioral
responses to SURTASS LFA sonar would be low given the MF/HF
specialists' observed lack of response to LFA sounds during the LFS SRP
and due to the MF/HF frequencies to which these animals are adapted to
hear (Clark and Southall, 2009).
Maybaum (1993) conducted sound playback experiments to assess the
effects of mid-frequency active sonar 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 the behavior, movement, and underwater
vocalizations. The two types of sonar signals 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 s upsweep 209 dB @ 1-2 kHz every 10 sec
for 10 minutes; Source B: With a 1.0 s upsweep 197 dB @ 6-7 kHz every
10 sec for 10 min). 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 (where killer whales cooperatively herd fish
schools into a tight ball towards the surface and feed on the fish
which have been stunned by tailslaps and subsurface feeding (Simila,
1997) 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 (BRS)
on deep diving odontocetes conducted by NMFS and other scientists
showed one beaked whale (Mesoplodon densirostris) responding to an MF
active sonar playback. The BRS-07 cruise report 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 BRS-07 cruise report notes that the results are from a single
experiment and that a greater sample size is needed before robust and
definitive conclusions can be drawn (NMFS, 2008a).
In the 2008 BRS study, researchers identified an emerging pattern
of responses of deep-diving beaked whales to MF active sonar playbacks.
For example, Blainville's beaked whales--a resident species within the
Tongue of the Ocean, Bahamas study area--appear to be sensitive to
noise at levels well below expected TTS (approximately 160 dB re:
1[mu]Pa at 1 m). 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 MF active
sonar, which suggests that beaked whales may not respond to the
specific sound signatures. Instead, they may be sensitive to any pulsed
sound from a point source in the frequency range of the MF active sonar
transmission. The response to such stimuli appears to involve the
beaked whale increasing the distance between it and the sound source
(NMFS, 2008b).
In the 2010 BRS study, researchers again used controlled exposure
experiments (CEE) to carefully measure behavioral responses of
individual animals to sound exposures of MF active sonar and pseudo-
random noise. For each sound type, some exposures were conducted when
animals were in a surface feeding (approximately 164 ft (50 m) or less)
and/or socializing behavioral state and others while animals were in a
deep feeding (greater than 164 ft (50 m)) and/or traveling mode. The
researchers conducted the largest number of CEEs on blue whales (n=19)
and of these, 11 CEEs involved exposure to the MF active sonar sound
type.
For the majority of CEE transmissions of either sound type, they
noted few obvious behavioral responses detected either by the visual
observers or on initial inspection of the tag data. The researchers
observed that throughout the CEE transmissions, up to the highest
received sound level (absolute RMS value approximately 160 dB re:
1[mu]Pa with signal-to-noise ratio values over 60 dB), two blue whales
continued surface feeding behavior and remained at a range of around
3,820 ft (1,000 m) from the sound source (Southall et al., 2011).

[[Page 868]]

In contrast, another blue whale (later in the day and greater than 11.5
mi (18.5 km; 10 nmi) from the first CEE location) exposed to the same
stimulus (MFA) while engaged in a deep feeding/travel state exhibited a
different response. In that case, the blue whale responded almost
immediately following the start of sound transmissions when received
sounds were just above ambient background levels (Southall et al.,
2011). However, the authors note that this kind of temporary avoidance
behavior was not evident in any of the nine CEEs involving blue whales
engaged in surface feeding or social behaviors, but was observed in
three of the ten CEEs for blue whales in deep feeding/travel behavioral
modes (one involving MFA sonar; two involving pseudo-random noise)
(Southall et al., 2011). The results of this study further illustrate
the importance of behavioral context in understanding and predicting
behavioral responses.
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 presences of predators have
occurred (Connor and Heithaus, 1996). Flight responses have been
speculated as being a component of marine mammal strandings associated
with MF active sonar activities (Evans and England, 2001). If marine
mammals respond to Navy vessels that are 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). In addition to the limited data on flight
response for marine mammals, there are examples for terrestrial
species. For instance, the probability of flight responses in Dall's
sheep Ovis dalli dalli (Frid, 2001a, 2001b), ringed seals Phoca hispida
(Born et al., 1999), Pacific brant (Branta bernicl nigricans), and
Canada geese (B. Canadensis) increased as a helicopter or fixed-wing
aircraft more directly approached groups of these animals (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).
Breathing. Variations in respiration naturally occur with different
behaviors. Variations in respiration rate as a function of acoustic
exposure can 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
foraging 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, exposing the same acoustic alarm to a striped dolphin under
the same conditions did not elicit a response (Kastelein et al.,
2006a), again highlighting the importance of understanding species
differences in the tolerance of underwater noise when determining the
potential for impacts resulting from anthropogenic sound exposure.
Continued Pre-disturbance Behavior and Habituation. Under some
circumstances, some of the individual marine mammals that are exposed
to active sonar transmissions will continue their normal behavioral
activities; in other circumstances, individual animals will respond to
sonar transmissions at lower received levels and move to avoid
additional exposure or exposures at higher received levels (Richardson
et al., 1995).
It is difficult to distinguish between animals that continue their
pre-disturbance behavior without stress responses, animals that
continue their behavior but experience stress responses (that is,
animals that cope with disturbance), and animals that habituate to
disturbance (that is, they may have experienced low-level stress
responses initially, but those responses abated over time). Watkins
(1986) reviewed data on the behavioral reactions of fin, humpback,
right and minke whales that were exposed to continuous, broadband low-
frequency shipping and industrial noise in Cape Cod Bay. He concluded
that underwater sound was the primary cause of behavioral reactions in
these species of whales and that the whales responded behaviorally to
acoustic stimuli within their respective hearing ranges. Watkins also
noted that whales showed the strongest behavioral reactions to sounds
in the 15 Hz to 28 kHz range, although negative reactions (avoidance,
interruptions in vocalizations, etc.) were generally associated with
sounds that were either unexpected, too loud, suddenly louder or
different, or perceived as being associated with a potential threat
(such as an approaching ship on a collision course). In particular,
whales seemed to react negatively when they were within 100 m of the
source or when received levels increased suddenly in excess of 12 dB
relative to ambient sounds. At other times, the whales ignored the
source of the signal and all four species habituated to these sounds.
Nevertheless, Watkins concluded that whales ignored most sounds in the
background of ambient noise, including sounds from distant human
activities even though these sounds may have had considerable energies
at frequencies well within the whales' range of hearing. Further, he
noted that of the whales observed, fin whales were the most sensitive
of the four species, followed by humpback whales; right whales were the
least likely to be disturbed and generally did not react to low-
amplitude engine noise. By the end of his period of study, Watkins
(1986) concluded that fin and humpback whales have generally habituated
to the continuous and broad-band noise of Cape Cod Bay while right
whales did not appear to change their response. As mentioned above,
animals that habituate to a particular disturbance may have experienced
low-level stress responses initially, but those responses abated over
time. In most cases, this likely means a lessened immediate potential
effect from a disturbance. However, there is cause for concern where
the habituation occurs in a potentially more harmful situation. For
example, animals may become more vulnerable to vessel strikes once they
habituate to vessel traffic (Swingle et al., 1993; Wiley et al., 1995).
Aicken et al., (2005) monitored the behavioral responses of marine
mammals to a new low-frequency active sonar system that was being
developed for use by the British Navy. During those trials, fin whales,
sperm whales, Sowerby's beaked whales, long-finned pilot whales
(Globicephala melas), Atlantic white-sided dolphins, and common
bottlenose dolphins were observed and their vocalizations were
recorded. These monitoring studies detected no evidence of behavioral
responses that the investigators could attribute to exposure to the
low-frequency active sonar during these trials.
Behavioral Responses. Southall et al. (2007) reviewed the available
literature on marine mammal hearing and physiological and behavioral
responses to human-made sound with the goal of

[[Page 869]]

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 no quantitative criteria were recommended for
behavioral responses. 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. LFA sonar is
considered a non-pulse sound. Southall et al. (2007) summarizes 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 following paragraphs).
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, 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 [mu]Pa at 1 m range and an increasing likelihood of avoidance and
other behavioral effects in the 120 to 160 dB re: 1 [mu]Pa at 1 m
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 a 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 including:
Pingers, drilling playbacks, ship and ice-breaking noise, vessel noise,
Acoustic Harassment Devices (AHDs), Acoustic Deterrent Devices (ADDs),
MF active sonar, 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 re: 1 [mu]Pa at 1 m,
while in other cases these responses were not seen in the 120 to 150 dB
re: 1 [mu]Pa at 1 m 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 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 (approximately 90-120 dB re: 1 [mu]Pa at 1 m), at least
for initial exposures. All recorded exposures above 140 dB re: 1 [mu]Pa
at 1 m 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 are no data to indicate whether other high-
frequency cetaceans are as sensitive to anthropogenic sound as harbor
porpoises.
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 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 suggest that exposure to non-pulse sounds between 90 and
140 dB re: 1 [mu]Pa at 1 m generally do not result in strong behavioral
responses of pinnipeds in water, but no data exist at higher received
levels.
In addition to summarizing the available data, Southall et al.
(2007) developed a behavioral response 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 is 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 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 greater than the 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 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).
In Table 22, NMFS has summarized the scores that Southall et al.
(2007) assigned to the papers that reported behavioral responses of
low-frequency cetaceans, mid-frequency cetaceans, and pinnipeds in
water to non-pulse sounds. This table is included simply to summarize
the findings of the studies and opportunistic observations (all of
which were capable of estimating received level) that Southall et al.
(2007) compiled in an effort to develop acoustic criteria.

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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 are few quantitative marine mammal data relating the
exposure of marine mammals to sound to effects on reproduction or
survival, though data exist for terrestrial species to which we can
draw comparisons for marine mammals. Several authors have reported that
disturbance stimuli cause animals to abandon nesting and foraging sites
(Sutherland and Crockford, 1993), cause animals to increase their
activity levels and suffer premature deaths or reduced reproductive
success when their energy expenditures exceed their energy budgets
(Daan et al., 1996; Feare, 1976; Giese, 1996; Mullner et al., 2004;
Waunters et al., 1997), or cause animals to experience higher predation
rates when they adopt risk-prone foraging or migratory strategies (Frid
and Dill, 2002). Each of these studies addressed the consequences of
animals shifting from one behavioral state (e.g., resting or foraging)
to another behavioral state (e.g., avoidance or escape behavior)
because of human disturbance or disturbance stimuli.
One consequence of behavioral avoidance results from the changes in
energetics of marine mammals because of the energy required to avoid
surface vessels or the sound field associated with active sonar (Frid
and Dill, 2002). Most animals can avoid that energetic cost by swimming
away at slow speeds or speeds that minimize the cost of transport
(Miksis-Olds, 2006), as has been demonstrated in Florida manatees
(Hartman, 1979; Miksis-Olds, 2006).
Those costs increase, however, when animals shift from a resting
state, which is designed to conserve an animal's energy, to an active
state that consumes energy the animal would have conserved had it not
been disturbed. Marine mammals that have been disturbed by
anthropogenic noise and vessel approaches are commonly reported to
shift from resting behavioral states to active behavioral states, which
would imply that they incur an energy cost.
Morete et al., (2007) reported that undisturbed humpback whale cows
that were accompanied by their calves were frequently observed resting
while their calves circled them (milling). When vessels approached, the
amount of time cows and calves spent resting and milling, respectively,
declined significantly. These results are similar to those reported by
Scheidat et al. (2004) for the humpback whales they observed off the
coast of Ecuador.
Constantine and Brunton (2001) reported that bottlenose dolphins in
the Bay of Islands, New Zealand only engaged in resting behavior five
percent of the time when vessels were within 300 m compared with 83
percent of the time when vessels were not present. Miksis-Olds (2006)
and Miksis-Olds et al. (2005) reported that Florida manatees in
Sarasota Bay, Florida, reduced the amount of time they spent milling
and increased the amount of time they spent feeding when background
noise levels increased. Although the acute costs of these changes in
behavior are not likely to exceed an animal's ability to compensate,
the chronic costs of these behavioral shifts are uncertain.
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
unconsciously (e.g., 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 treating the stimulus as a
disturbance and responding 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 attend to cues from prey (Bednekoff

[[Page 871]]

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 (e.g., multiple surface vessels), or when they co-occur with
times that an animal perceives increased risk (e.g., 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. An example of
this concept with terrestrial species involved bighorn sheep and Dall's
sheep, which dedicated more time to 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
physical 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 (Anser brachyrhynchus) 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 other non-marine mammal
species; for example, mule deer (Odocoileus hemionus) disturbed by all-
terrain vehicles (Yarmoloy et al., 1988), caribou disturbed by seismic
exploration blasts (Bradshaw et al., 1998), and caribou disturbed by
low-elevation military jet flights (Luick et al., 1996; Harrington and
Veitch, 1992). Similarly, a study of elk (Cervus elaphus) 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, reducing the time they might spend foraging and
resting (which increases an animal's activity rate and energy demand).
An example of this concept with terrestrial species involved, a study
of grizzly bears (Ursus horribilis) which reported that bears disturbed
by hikers reduced their energy intake by an average of 12 kilocalories/
min (50.2 x 10\3\ kiloJoules/min), 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 five-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-hr
cycle). 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 one day and not
recurring on subsequent days is not considered particularly severe
unless it could directly affect reproduction or survival (Southall et
al., 2007).

Stranding and Mortality

When a live or dead marine mammal swims or floats onto shore and
becomes ``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 under the MMPA 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 is 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 pre-
dispose 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).

Strandings Associated With Active Sonar

Several sources have published lists of mass stranding events of
cetaceans in an attempt to identify relationships between those
stranding events and military active 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 and 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 MF active sonar and
most involved beaked whales.
Over the past 12 years, there have been five stranding events
coincident with military MF active sonar use in which exposure to sonar
is believed by NMFS and the Navy to have been a contributing factor to
strandings: Greece (1996); the Bahamas (2000); Madeira (2000); Canary
Islands (2002); and Spain (2006). NMFS refers the reader to Cox et al.
(2006) for a summary of common features shared by the strandings events
in Greece (1996), Bahamas (2000), Madeira (2000), and Canary Islands
(2002); and Fernandez et al., (2005) for an additional summary of the
Canary Islands 2002 stranding event. 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 the Hanalei
Bay, Kaua'i, Hawaii for over 28 hours. NMFS determined that the mid-
frequency

[[Page 872]]

sonar was a plausible, if not likely, contributing factor in what may
have been a confluence of events that led to the Hanalei Bay stranding.
A number of other stranding events coincident with the operation of MF
active 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
exercises was conducted by the U. S. Navy.

Potential for Stranding From LFA Sonar

There is no empirical evidence of strandings of marine mammals
associated with the employment of SURTASS LFA sonar since its use began
in the early 2000s. Moreover, the system acoustic characteristics
differ between LF and MF sonars: LFA sonars use frequencies generally
below 1,000 Hz, with relatively long signals (pulses) on the order of
60 sec; while MF sonars use frequencies greater than 1,000 Hz, with
relatively short signals on the order of 1 sec.
As discussed previously, Cox et al. (2006) provided a summary of
common features shared by the strandings events in Greece (1996),
Bahamas (2000), and Canary Islands (2002). These included deep water
close to land (such as offshore canyons), presence of an acoustic
waveguide (surface duct conditions), and periodic sequences of
transient pulses (i.e., rapid onset and decay times) generated at
depths less than 32.8 ft (10 m) by sound sources moving at speeds of
2.6 m/s (5.1 knots) or more during sonar operations (D'Spain et al.,
2006). These features do not relate to LFA sonar operations. First, the
SURTASS LFA sonar vessel operates with a horizontal line array of
4,921ft (1,500 m) length at depths below 492 ft (150 m) and a vertical
line array (LFA sonar source) at depths greater than 328 ft (100 m).
Second, the Navy will not operate SURTASS LFA sonar within 22 km (13.
mi; 11.8 nm) of any coastline. For these reasons, SURTASS LFA sonar
cannot be operated in deep water that is close to land. Also, the LFA
sonar signal is transmitted at depths well below 32.8 ft (10 m). While
there was an LF component in the Greek stranding in 1996, only MF
components were present in the strandings in the Bahamas in 2000,
Madeira 2000, and Canaries in 2002. The International Council for the
Exploration of the Sea (ICES) in its ``Report of the Ad-Hoc Group on
the Impacts of Sonar on Cetaceans and Fish'' raised the same issues as
Cox et al., (2006) stating that the consistent association of MF sonar
in the Bahamas, Madeira, and Canary Islands strandings suggest that it
was the MF component, not the LF component, in the NATO sonar that
triggered the Greek stranding of 1996 (ICES, 2005). The ICES (2005)
report concluded that no strandings, injury, or major behavioral change
have been associated with the exclusive use of LF sonar.

Concurrent Use of LF and MF Active Sonar

The environmental impacts of the SURTASS LFA sonar system,
including the potential for synergistic and cumulative effects with MF
active sonar operation, has been addressed in detail in the Navy's
application and the SURTASS LFA sonar 2011 DSEIS/SOEIS. NMFS will not
consider the authorization of take of marine mammals incidental to the
operation of MF active sonar in this document because NMFS has already
separately authorized the incidental take associated with these
activities. NMFS has considered more specifically the manner in which
LFA sonar and MFAS may interact in a multi-strike group exercise with
respect to the potential to impact marine mammals in a manner not
previously considered.
Tactical and technical considerations dictate that the LFA sonar
ship would typically be tens of miles from the MF active sonar ship
when using active sonar. It is unlikely, but remotely possible, that
both LF and MF active sonar would be active at exactly the same time
during a major exercise. Based on the differing operating
characteristics of each sonar (pulse length, duty cycle, etc.), the
percentage of overlap during concurrent MF and LF active sonar
operations is approximately 0.017 percent. In the unlikely event that
both systems were transmitting simultaneously, the likelihood of more
than a relatively small number of individual marine mammals being
physically present at a time, location, and depth to be able to receive
both LF and MF active sonar signals at levels of concern at the same
time is even smaller as the sound from both signals would have
attenuated when they reached the marine mammal in question, so even a
simultaneous exposure would not be at the full signal of either system.
Additionally, only a few species have maximum sensitivity to both the
low and middle frequencies.

Potential Effects of Vessel Movement and Collisions

Vessel movement in the vicinity of marine mammals has the potential
to result in either a behavioral response or a direct physical
interaction. Both scenarios are discussed below.

Behavioral Responses to Vessel Movement

There are limited data concerning marine mammal behavioral
responses to vessel traffic and vessel noise, and a lack of consensus
among scientists with respect to what these responses mean or whether
they result in short-term or long-term adverse effects. In those cases
where there is a busy shipping lane or where there is a large amount of
vessel traffic, marine mammals may experience acoustic masking
(Hildebrand, 2005) if they are present in the area (e.g., killer whales
in Puget Sound; Foote et al., 2004; Holt et al., 2008). In cases where
vessels actively approach marine mammals (e.g., whale watching or
dolphin watching boats), scientists have documented that animals
exhibit altered behavior such as increased swimming speed, erratic
movement, and active avoidance behavior (Bursk, 1983; Acevedo, 1991;
Baker and MacGibbon, 1991; Trites and Bain, 2000; Williams et al.,
2002; Constantine et al., 2003), reduced blow interval (Ritcher et al.,
2003), disruption of normal social behaviors (Lusseau, 2003; 2006), and
the shift of behavioral activities which may increase energetic costs
(Constantine et al., 2003; 2004). A detailed review of marine mammal
reactions to ships and boats is available in Richardson et al. (1995).
For each of the marine mammal taxonomy groups, Richardson et al. (1995)
provides the following assessment regarding cetacean reactions to
vessel traffic:
Toothed whales: ``In summary, toothed whales sometimes show no
avoidance reaction to vessels, or even approach them. However,
avoidance can occur, especially in response to vessels of types used to
chase or hunt the animals. This may cause temporary displacement, but
we know of no clear evidence that toothed whales have abandoned
significant parts of their range because of vessel traffic.''
Baleen whales: ``When baleen whales receive low-level sounds from
distant or stationary vessels, the sounds often seem to be ignored.
Some whales approach the sources of these sounds. When vessels approach
whales slowly and non-aggressively, whales often exhibit slow and
inconspicuous avoidance maneuvers. In response to strong or rapidly
changing vessel noise, baleen whales often interrupt their normal
behavior and swim rapidly away. Avoidance is especially strong when a
boat heads directly toward the whale.''

[[Page 873]]

Behavioral responses to stimuli are complex and influenced to
varying degrees by a number of factors, such as species, behavioral
contexts, geographical regions, source characteristics (moving or
stationary, speed, direction, etc.), prior experience of the animal and
physical status of the animal. For example, studies have shown that
beluga whales' reactions varied when exposed to vessel noise and
traffic. In some cases, naive beluga whales exhibited rapid swimming
from ice-breaking vessels up to 80 km (49.7 mi) away, and showed
changes in surfacing, breathing, diving, and group composition in the
Canadian high Arctic where vessel traffic is rare (Finley et al.,
1990). In other cases, beluga whales were more tolerant of vessels, but
responded differentially to certain vessels and operating
characteristics by reducing their calling rates (especially older
animals) in the St. Lawrence River where vessel traffic is common
(Blane and Jaakson, 1994). In Bristol Bay, Alaska, beluga whales
continued to feed when surrounded by fishing vessels and resisted
dispersal even when purposefully harassed (Fish and Vania, 1971).
In reviewing more than 25 years of whale observation data, Watkins
(1986) concluded that whale reactions to vessel traffic were ``modified
by their previous experience and current activity: habituation often
occurred rapidly, attention to other stimuli or preoccupation with
other activities sometimes overcame their interest or wariness of
stimuli.'' Watkins noticed that over the years of exposure to ships in
the Cape Cod area, minke whales changed from frequent positive interest
(e.g., approaching vessels) to generally uninterested reactions; fin
whales changed from mostly negative (e.g., avoidance) to uninterested
reactions; right whales apparently continued the same variety of
responses (negative, uninterested, and positive responses) with little
change; and humpbacks dramatically changed from mixed responses that
were often negative to reactions that were often strongly positive.
Watkins (1986) summarized that ``whales near shore, even in regions
with low vessel traffic, generally have become less wary of boats and
their noises, and they have appeared to be less easily disturbed than
previously. In particular locations with intense shipping and repeated
approaches by boats (such as the whale-watching areas of Stellwagen
Bank), more and more whales had positive reactions to familiar vessels,
and they also occasionally approached other boats and yachts in the
same ways.''
Although the radiated sound from Navy vessels will be audible to
marine mammals over a large distance, it is unlikely that animals will
respond behaviorally (in a manner that NMFS would consider MMPA
harassment) to low-level distant shipping noise as the animals in the
area are likely to be habituated to such noises (Nowacek et al., 2004).
In light of these facts, NMFS does not expect the Navy's vessel
movements to result in Level B harassment.

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
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 14.9 mph (24.1 km/hr; 13 kts).
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 kts.
The majority (79 percent) of these strikes occurred at speeds of 13 kts
or greater. The average speed that resulted in serious injury or death
was 18.6 kts. 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 percent to 75 percent as vessel speed increased from
10 to 14 kts, and exceeded 90 percent at 17 kts. 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.
The Navy's proposed operation of up to four SURTASS LFA sonar
vessels world-wide is relatively small in scale compared to the number
of commercial ships transiting at higher speeds in the same areas on an
annual basis. The probability of vessel and marine mammal interactions
occurring during SURTASS LFA operations is unlikely due to the
surveillance vessel's slow operational speed, which is typically 3.4
mph (5.6 km/hr; 3 kts). Outside of operations, each vessel's cruising
speed would be approximately 11.5 to 14.9 mph (18.5 to 24.1 km/hr; 10
to 13 kts) which is generally below the speed at which studies have
noted reported increases of marine mammal injury or death (Laist et
al., 2001). Second, the Navy would restrict the operation of SURTASS
LFA vessels at a distance of 1 km (0.62 mi; 0.54 nmi) seaward of the
outer perimeter of any OBIA designated for marine mammals during a
specified period, further minimizing the potential for marine mammal
interactions. Also, the Navy would not operate SURTASS

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LFA vessels a distance of 22 km (13. mi; 11.8 nmi) or less of any
coastline, including islands, thus operating in offshore coastal areas
with lower densities of marine mammals would minimize adverse impacts.
As a final point, the SURTASS LFA surveillance vessels have a
number of other advantages for avoiding ship strikes as compared to
most commercial merchant vessels, including the following: The T-AGOS
ships have their bridges positioned forward of the centerline, offering
good visibility ahead of the bow and good visibility aft to visually
monitor for marine mammal presence; lookouts posted during operations
scan the ocean for marine mammals and must report visual alerts of
marine mammal presence to the Deck Officer; Navy lookouts receive
extensive training that covers the fundamentals of visual observing for
marine mammals and information about marine mammals and their
identification at sea; and SURTASS LFA vessels travel at 3-4 kts
(approximately 3.4 mph; 5.6 km/hr) with deployed arrays. For a thorough
discussion of mitigation measures, please see the Mitigation section
later in this document.

Anticipated Effects on Marine Mammal Habitat

The Navy's proposed routine testing and training, as well as
military operations using SURTASS LFA sonar, could potentially affect
marine mammal habitat through the introduction of pressure and sound
into the water column, which in turn could impact prey species of
marine mammals.
Based on the following information and the supporting information
included in the Navy's application, the 2001 FOEIS/EIS, the 2007 FSEIS,
and the 2011 DSEIS/SOEIS, NMFS has preliminarily determined that
SURTASS LFA sonar operations will not have significant or long-term
impacts on marine mammal habitat. Unless the sound source 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. Marine mammals may be temporarily displaced
from areas where SURTASS LFA operations are occurring, but the area
will likely be utilized again after the activities have ceased. A
summary of the conclusions are included in subsequent sections.

Compliance With Maritime Law

Use of SURTASS LFA sonar entails the periodic deployment of
acoustic transducers and receivers into the water column from ocean-
going ships. The Navy deploys SURTASS LFA sonar from ocean surveillance
ships that are U.S. Coast Guard-certified for operations and operate in
accordance with all applicable federal, international, and U.S. Navy
rules and regulations related to environmental compliance, especially
for discharge of potentially hazardous materials. SURTASS LFA sonar
ships comply with all requirements of the Clean Water Act of 1972 (CWA;
33 U.S.C. section 1251 et seq.) and Act to Prevent Pollution from Ships
(APPS; 33 U.S.C. subsections 1905-1915). SURTASS LFA vessel movements
are not unusual or extraordinary and are part of routine operations of
seagoing vessels. Therefore, no discharges of pollutants regulated
under the APPS or CWA will result from the operation of the sonar
systems nor will any unregulated environmental impacts from the
operation of the SURTASS LFA sonar vessels occur.

Geographic Restrictions

The Navy has proposed that the sound field does not exceed 180 dB
re: 1 [micro]Pa at 1 m (i.e., a mitigation zone) within 22 km (13. mi;
11.8 nmi) of any coastline, including islands, or within proposed OBIAs
during biologically important seasons, during the conduct of SURTASS
LFA operations.

Critical Habitat

Of the designated critical habitat for marine mammals, four areas
are at a distance sufficient from shore to potentially be affected by
SURTASS LFA sonar. They are the critical habitat for the north Atlantic
right whale (NARW), north Pacific right whale (NPRW), Hawaiian monk
seal, and Steller sea lion. The Navy proposes that the sound field
would not exceed 180 dB re: 1 [micro]Pa at 1 m in the areas designated
as critical habitat for the north Atlantic right whale, north Pacific
right whale, and the Hawaiian monk seal.
For NARW critical habitat, the Navy has proposed an OBIA that
encompasses the critical habitats of the North Atlantic right whale in
Georges Bank (OBIA 1); Roseway Basin right whale Conservation
Area (OBIA 2); in portions of the Gulf of Maine including
Stellwagen Bank National Marine Sanctuary, that are located outside of
22 km (13. mi; 11.8 nmi) (OBIA 3); and the southeastern U.S.
Right whale Seasonal critical habitat (OBIA 4). In 2008, NMFS
designated two areas of critical habitat for the NPRW, one in the
Bering Sea where the Navy proposes to not conduct SURTASS LFA sonar
operations. For the other designated area for critical habitat in the
Gulf of Alaska, the Navy has proposed an OBIA (5) that bounds
the designated critical habitat for the species.
Much of the proposed critical habitat for Hawaiian monk seals is
within 22 km (13. mi; 11.8 nmi) of any shoreline and there is no
proposed OBIA that encompasses the entirety of Hawaiian monk seal
critical habitat. However, the Navy has proposed an OBIA (16)
that encompasses the Penguin Bank portion of the Hawaiian Islands
Humpback Whale National Marine Sanctuary.
There is no proposed OBIA that encompasses designated critical
habitat for Steller sea lions. Much of the critical habitat for the
Steller sea lion is located in the Bering Sea, where SURTASS LFA sonar
will not operate. Although it is possible that the sonar will be
operated in the western Gulf of Alaska where the eastern critical
habitat for the Steller sea lion is located and some of that habitat
lies outside of 22 km (13. mi; 11.8 nmi) from shore, the water depth in
which the habitat is found is sufficiently shallow that it is unlikely
that the Navy would operate sonar in the vicinity of that critical
habitat.
Both the Navy and NMFS will consult with NMFS on effects on
critical habitat pursuant to section 7 of the ESA.

Marine Protected Areas (MPA)

Within the National System of MPAs, seven formally recognized areas
are in potential SURTASS LFA sonar operating areas because a portion of
the area or its seaward boundary is located beyond 22 km (13. mi; 11.8
nmi) from the coastline. These MPAs are: Stellwagen Bank National
Marine Sanctuary (NMS); Olympic Coast NMS; Gulf of the Farallones NMS;
Monterey Bay NMS; Cordell Bank NMS; Hawaiian Islands Humpback Whale
NMS; and Papahanaumokuakea Marine National Monument. The Navy has
proposed not to operate SURTASS LFA sonar in specified areas of
National Marine Sanctuaries during biologically important seasons (see
OBIA section discussed later in this document).
The proposed SURTASS LFA operations are not anticipated to have any
permanent impact on habitats used by the marine mammals in the proposed
operational areas, including the food sources they use (i.e., fish and
invertebrates). Additionally, no physical damage to any habitat is
anticipated as a result of conducting the proposed SURTASS LFA
operations. While it is

[[Page 875]]

anticipated that the specified activity may result in marine mammals
avoiding certain areas due to temporary ensonification, this impact to
habitat is temporary and reversible and was considered in further
detail earlier in this document, as behavioral modification. The main
impact associated with the proposed activity will be temporarily
elevated noise levels and the associated direct effects on marine
mammals, previously discussed in this notice.

Anticipated Impacts on Fish

The Navy's DSEIS/SOEIS includes a detailed discussion of the
effects of active sonar on marine fish and several studies on the
effects of both Navy sonar and seismic airguns that are relevant to
potential effects of SURTASS LFA sonar on osteichthyes (bony fish). In
the most pertinent of these, the Navy funded independent scientists to
analyze the effects of SURTASS LFA sonar on fish (Popper et al., 2005a,
2007; Halvorsen et al., 2006) and on the effects of SURTASS LFA sonar
on fish physiology (Kane et al., 2010).
Several studies on the effects of SURTASS LFA sonar sounds on three
species of fish (rainbow trout, channel catfish, and hybrid sunfish)
examined long-term effects on sensory hair cells of the ear. In all
species, even up to 96 hours post-exposure, there were no indications
of damage to sensory cells (Popper et al., 2005a, 2007; Halvorsen et
al., 2006). Recent results from direct pathological studies of the
effects of LFA sounds on fish (Kane et al., 2010) provide evidence that
SURTASS LFA sonar sounds at relatively high received levels (up to 193
dB re: 1 [mu]Pa at 1 m) have no pathological effects or short- or long-
term effects to ear tissue on the species of fish that have been
studied.

Anticipated Impacts on Invertebrates

Among invertebrates, only cephalopods (octopus and squid) and
decapods (lobsters, shrimps, and crabs) are known to sense LF sound
(Packard et al., 1990; Budelmann and Williamson, 1994; Lovell et al.,
2005; Mooney et al., 2010). Popper and Schilt (2008) stated that, like
fish, some invertebrate species produce sound, possibly using it for
communications, territorial behavior, predator deterrence, and mating.
Well known sound producers include the lobster (Panulirus spp.) (Latha
et al., 2005), and the snapping shrimp (Alpheus heterochaelis)
(Herberholtz and Schmitz, 2001).
Andre et al. (2011) exposed four cephalopod species (Loligo
vulgaris, Sepia officinalis, Octopus vulgaris, and Ilex coindetii) to
two hours of continuous sound from 50 to 400 Hz at 157 5
dB re: 1 [mu]Pa. They reported lesions to the sensory hair cells of the
statocysts of the exposed animals that increased in severity with time,
suggesting that cephalopods are particularly sensitive to low-frequency
sound. However, the Navy notes in the DSEIS/SOEIS (Chapter 3-6) that
the authors failed to elaborate that there were no anthropogenic
sources to which animals might be exposed with characteristics similar
to those used in their study. The time sequence of exposure from low-
frequency sources in the open ocean would be about once every 10 to 15
min for SURTASS LFA. Therefore, the study's sound exposures were longer
in duration and higher in energy than any exposure a marine mammal
would likely ever receive and acoustically very different than a free
field sound to which animals would be exposed in the real world. Given
the lack of data on hearing thresholds of cephalopods, SURTASS LFA
sonar operations could only have a lasting impact on these animals if
they are within a few tens of meters from the source. In conclusion,
NMFS does not expect any short- or long-term effects to marine mammal
food resources from SURTASS LFA sonar activities.

Proposed Mitigation

In order to issue an incidental take authorization (ITA) 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
section 101(a)(5)(A) of the MMPA 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 activities described in the SURTASS
LFA sonar application are considered military readiness activities.
NMFS reviewed the proposed SURTASS LFA sonar activities and the
proposed mitigation measures as described in the Navy's 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.''
To reduce the potential for impacts from acoustic stimuli
associated with the Navy's SURTASS LFA sonar activities, the Navy has
proposed to implement the following mitigation measures for marine
mammals:
(1) LFA sonar mitigation zone--LF sources transmissions are
suspended if the Navy detects marine mammals within the mitigation
zones by any of the following detection methods:
(a) Visual monitoring;
(b) Passive acoustic monitoring;
(c) Active acoustic monitoring;
(2) Geographic restrictions in the following areas:
(a) Offshore Biologically Important Areas (OBIAs);
(b) Coastal Standoff Zone.
Additionally, as with the previous rulemaking, NMFS proposes to
include additional operational restrictions for SURTASS LFA sonar
operations:
(1) Additional 1-km buffer around the LFA sonar mitigation zone;
and
(2) Additional 1-km buffer around an OBIA perimeter.
Both the Navy's proposed mitigation and NMFS' additional proposed
mitigation are discussed below this section.

LFA Sonar Mitigation Zone

The Navy has proposed in its application to establish a 180-dB (RL)
isopleth LFA sonar mitigation zone around the surveillance vessel. If a
marine mammal approaches or enters the LFA sonar mitigation zone, the
Navy would implement a suspension of SURTASS LFA sonar transmissions.
Prior to commencing and during SURTASS LFA transmissions, the Navy
will determine the propagation of LFA sonar signals in the ocean and
the distance from the SURTASS LFA sonar source to the 180-dB isopleth
(See Description of Real-Time SURTASS LFA Sonar Sound Field Modeling
section). The 180-dB isopleth will define the LFA sonar mitigation zone
for marine mammals around the surveillance vessel.
The Navy modeling of the sound field in near-real time conditions
provides the information necessary to modify SURTASS LFA operations,
including the delay or suspension of LFA transmissions. Acoustic model
updates are nominally made every 12 hr, or more frequently when
meteorological or oceanographic conditions change. If the sound field
criteria were exceeded, the sonar operator would notify the Officer in
Charge (OIC), who would order the delay or suspension of transmissions.
If it were predicted that the SPLs would

[[Page 876]]

exceed the criteria within the next 12 hr period, the OIC would also be
notified in order to take the necessary action to ensure that the sound
field criteria would not be exceeded.

NMFS' Additional 1-km Buffer Zone Around the LFA Sonar Mitigation Zone

As an added measure, NMFS again proposes to require a ``buffer
zone'' that extends an additional 1 km (0.62 mi; 0.54 nm) beyond the
180-dB isopleth LFA sonar mitigation zone. This buffer coincides with
the full detection range of the HF/M3 active sonar for mitigation
monitoring (approximately 2 to 2.5 km; 1.2 to 1.5 mi; 1.1 to 1.3 nmi).
Thus, the 180-dB isopleth for the LFA sonar mitigation zone, plus NMFS'
1-km (0.54 nm) buffer zone would comprise the entire mitigation zone
for SURTASS LFA sonar operations, wherein suspension of transmissions
would occur if a marine mammal approaches or enters either zone. The
Navy notes in its application that this additional mitigation is
practicable and it would adhere to this additional measure if required
in the proposed rule.
In addition to establishing a 180-dB (RL) isopleth LFA sonar
mitigation zone around the surveillance vessel the Navy has also
proposed to establish a mitigation zone for human divers at 145 dB re:
1 [micro]Pa at 1 m around all known human commercial and recreational
diving sites. Although this geographic restriction is intended to
protect human divers, it will also reduce the LF sound levels received
by marine mammals located in the vicinity of known dive sites.

Visual Mitigation Monitoring

The use of shipboard lookouts is a critical component of all Navy
mitigation measures. Navy shipboard 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 Deck Officer
(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
serving as lookouts on station at all times (day and night) when a ship
or surfaced submarine is moving through the water.
Visual monitoring consists of daytime observations by lookouts
(personnel trained in detecting and identifying marine mammals) for
marine mammals from the vessel. The objective of these observations is
to maintain a bearing of marine mammals observed and to ensure that
none approach the source close enough to enter the LFA mitigation zone
or the 1-km buffer zone proposed by NMFS (see Additional Mitigation
Measure Proposed by NMFS section).
Daylight is defined as 30 min before sunrise until 30 min after
sunset. Visual monitoring would begin 30 min before sunrise or 30 min
before the Navy deploys the SURTASS LFA sonar array. Lookouts will
continue to monitor the area until 30 min after sunset or until
recovery of the SURTASS LFA sonar array.
The lookouts would maintain a topside watch and marine mammal
observation log during operations that employ SURTASS LFA sonar in the
active mode. These trained monitoring personnel maintain a topside
watch and scan the water's surface around the vessel systematically
with standard binoculars (7x) and with the naked eye. If the lookout
sights a possible marine mammal, the lookout will use big-eye
binoculars (25x) to confirm the sighting and potentially identify the
marine mammal species. Lookouts will enter numbers and identification
of marine mammals sighted, as well as any unusual behavior, into the
log. A designated ship's officer will monitor the conduct of the visual
watches and periodically review the log entries.
If a lookout observes a marine mammal outside of the LFA mitigation
or buffer zone, the lookout will notify the OIC. The OIC shall then
notify the HF/M3 sonar operator to determine the range and projected
track of the marine mammal. If the HF/M3 sonar operator or the lookout
determines that the marine mammal will pass within the LFA mitigation
or buffer zones, the OIC shall order the delay or suspension of SURTASS
LFA sonar transmissions when the animal enters the LFA mitigation or
buffer zone to prevent Level A harassment. The lookout will enter his/
her observations into the log. This would include tabular information
that includes: Date/time; vessel name; LOA area; marine mammals
affected (number and type); assessment basis (observed injury,
behavioral response, or model calculation); LFA mitigation or buffer
zone radius; bearing from vessel; whether operations were delayed,
suspended or terminated; and a narrative.
If a lookout observes a marine mammal anywhere within the LFA
mitigation or 1-km buffer zone (as proposed by NMFS), the lookout shall
notify the OIC who will promptly order the immediate delay or
suspension of SURTASS LFA sonar transmissions. The lookout will enter
his/her observations into the log.
Marine mammal biologists, who are qualified in conducting at-sea
marine mammal visual monitoring from surface vessels, shall train and
qualify designated ship personnel to conduct at-sea visual monitoring.
The Navy will hire one or more marine mammal biologists qualified in
conducting at-sea marine mammal visual monitoring from surface vessels
to train and qualify designated ship personnel to conduct at-sea visual
monitoring.

Passive Acoustic Mitigation Monitoring

For the second of the three-part mitigation monitoring measures,
the Navy proposes to conduct passive acoustic monitoring using the
SURTASS towed horizontal line array to listen for vocalizing marine
mammals as an indicator of their presence. This system serves to
augment the visual and active sonar detection systems. If a passive
acoustic technician detects a vocalizing marine mammal that may be
potentially affected by SURTASS LFA sonar prior to or during
transmissions, the technician will notify the OIC who will immediately
alert the HF/M3 active sonar operators and the lookouts. The OIC will
order the delay or suspension of SURTASS LFA sonar transmissions when
the animal enters the LFA mitigation or buffer zone as detected by
either the HF/M3 sonar operator or the lookouts. The passive acoustic
technician will record all contacts of marine mammals into the log.

Active Acoustic Mitigation Monitoring

HF active acoustic monitoring uses the HF/M3 sonar to detect,
locate, and track marine mammals that could pass close enough to the
SURTASS LFA sonar array to enter the LFA sonar mitigation or buffer
zones. HF/M3 acoustic monitoring begins 30 min before the first SURTASS
LFA sonar transmission of a given mission is scheduled to commence and
continues until the Navy terminates the transmissions.
If the HF/M3 sonar operator detects a marine mammal contact outside
the LFA sonar mitigation zone or buffer zones, the HF/M3 sonar operator
shall determine the range and projected track of the marine mammal. If
the operator determines that the marine mammal will pass within the LFA
sonar mitigation or buffer zones, he/she shall notify the OIC. The OIC
then immediately orders the delay or suspension of transmissions when
the animal is predicted to enter the LFA sonar mitigation or buffer
zones.
If the HF/M3 sonar operator detects a marine mammal within the LFA
mitigation or buffer zones, he/she shall

[[Page 877]]

notify the OIC who will immediately order the delay or suspension of
transmissions. The HF/M3 sonar operator will record all contacts of
marine mammals into the log.
Prior to full-power operations of the HF/M3 active sonar, the Navy
will ramp up the HF/M3 sonar power level over a period of 5 min from
the source level of 180 dB re 1 [mu]Pa at 1 m in 10-dB increments until
the system attains full power (if required) to ensure that there are no
inadvertent exposures of marine mammals to received levels greater than
180 dB re 1 [mu]Pa from the HF/M3 sonar. The Navy will not increase the
HF/M3 sonar source level if any of the three monitoring programs detect
a marine mammal during ramp-up. Ramp-up may continue once marine
mammals are no longer detected by any of the three monitoring programs.
Prior to any SURTASS LFA sonar calibrations or testing that are not
part of regular SURTASS LFA sonar transmissions, the Navy will ramp up
the HF/M3 sonar power level over a period of 5 min from the source
level of 180 dB re 1 [mu]Pa at 1 m in 10-dB increments until the system
attains full power. The Navy will not increase the HF/M3 source level
if any of the three monitoring programs detect a marine mammal during
ramp-up. Ramp-up may continue once marine mammals are no longer
detected by any of the three monitoring programs.
In situations where the HF/M3 sonar system has been powered down
for more than 2 min, the Navy will ramp up the HF/M3 sonar power level
over a period of 5 min from the source level of 180 dB re 1 [mu]Pa at 1
m in 10-dB increments until the system attains full power.

Past Mitigation Monitoring Under the Previous Rules

For the first four LOA periods under the 2007 rule, the Navy has
reported a total of eight visual sightings, four passive acoustic
detections, and 29 HF/M3 active sonar detections (DoN, 2008; 2009a;
2010; 2011) leading to mitigation protocols of suspensions/delays of
transmissions in a total of 70 missions.
During the 2002-2007 rule period, the Navy reported a total of four
visual sightings, no passive acoustic detections, and 101 active HF/M3
active sonar detections leading to mitigation protocols of suspensions/
delays of transmissions (DoN, 2007a; 2007b) in a total of 58 missions.
However, these data sets involving marine species are too small to
support any meaningful analyses, such as determining if there are any
differences in detection during the time when LFA sonar is active
versus when it is inactive.

Geographic Restrictions

As noted above, the Navy has proposed two types of geographic
restrictions for SURTASS LFA operations in the LOA application: (1)
establishing OBIAs for marine mammal protection and restricting SURTASS
LFA sonar operations within these designated areas such that the
SURTASS LFA sonar-generated sound field will not exceed 180 dB re: 1
[mu]Pa (RL); and (2) restricting SURTASS LFA sonar operations within 22
km (13. mi; 11.8 nmi) of any coastline, including islands.

Offshore Biologically Important Areas

As with the previous SURTASS LFA sonar rulemakings, the Navy's
application again proposed establishing offshore biologically important
areas OBIAs for marine mammal protection. In preparation for this rule
making, NMFS developed a more systematic process for selecting,
assessing, and designating OBIAs for SURTASS LFA sonar.
First, NMFS developed screening criteria to help initially select
potential areas and then determine an area's eligibility for
consideration as an OBIA nominee. These OBIA screening criteria
included:
(1) Areas with:
(a) High densities of marine mammals; or
(b) Known/defined breeding/calving grounds, foraging grounds,
migration routes; or
(c) Small, distinct populations of marine mammals with limited
distributions; and
(2) Areas that are outside of the coastal standoff distance and
within potential operational areas for SURTASS LFA (i.e., greater than
22 km (13.6 mi; 12 nmi) from any shoreline and not in polar regions).
NMFS used the screening criteria to review 403 existing and
potential marine protected areas based on the World Database on
Protected Areas (WDPA) (IUCN and UNEP, 2009), Holt (2005), and prior
SURTASS LFA sonar OBIAs to produce a preliminary list of 27 OBIA
nominees.
NMFS next convened an expert review panel of biologists
knowledgeable about potentially affected marine mammal biologically
important areas. This panel consisted of subject matter experts (SME),
each with expertise in geographic regions including the Atlantic Ocean,
Pacific Ocean, Mediterranean Sea, Indian Ocean/Southeast Asia, and East
Africa. The SMEs provided their individual analyses of NMFS'
preliminary candidates as potential marine mammal OBIAs in waters where
the Navy potentially could use the SURTASS LFA sonar systems and
provided additional recommendations for other OBIAs. This resulted in a
total number of 73 potential OBIAs. These areas were further screened
for sufficient scientific support, resulting in 45 potential OBIAs.
Although not part of its initial screening criteria, consideration
of marine mammal hearing frequency sensitivity led NMFS to screen out
areas that qualified solely on the basis of their importance for mid-
or high-frequency hearing specialists. The LFA sound source is well
below the range of best hearing sensitivity for most MF and HF
odontocete hearing specialists. This means, for example, for harbor
porpoises, that a sound with a frequency less than 1 kHz needs to be
significantly louder (more than 40 dB louder) than a sound in their
area of best sensitivity (around 100 kHz) in order for them to hear it.
Additionally, during the 1997 to 1998 SURTASS LFA Sonar Low Frequency
Sound Scientific Research Program (LFS SRP), numerous odontocete and
pinniped species (i.e., MF and HF hearing specialists) were sighted in
the vicinity of the sound exposure tests and showed no immediately
obvious responses or changes in sighting rates as a function of source
conditions, which likely produced received levels similar to those that
produced minor short-term behavioral responses in the baleen whales
(i.e., LF hearing specialists). NMFS believes that MF and HF odontocete
hearing specialists have such reduced sensitivity to the LFA source
that limiting ensonification in OBIAs for those animals would not
afford protection beyond that which is already incurred by implementing
a shutdown when any marine mammal enters the LFA mitigation and buffer
zones. Consideration of this additional information resulted in a list
of 22 final OBIA nominees for the Navy's consideration.
The 22 areas are: (1) Georges Bank, year round; (2) Roseway Basin
Right Whale Conservation Area, June through December; (3) the Great
South Channel, U.S. Gulf of Maine, and Stellwagen Bank NMS, January 1
to November 14; (4) the Southeastern U.S. Right Whale Seasonal Habitat,
November 15 to January 15; (5) the North Pacific Right Whale Critical
Habitat, March through August; (6) Silver Bank and Navidad Bank,
December through April; (7) the coastal waters of Gabon, Congo and

[[Page 878]]

Equatorial Guinea, June through October; (8) the Patagonian Shelf
Break, year round; (9) Southern Right Whale Seasonal Habitat, May
through December; (10) the central California National Marine
Sanctuaries, June through November; (11) the Antarctic Convergence
Zone, October through March; (12) Piltun and Chayvo offshore feeding
grounds in the Sea of Okhotsk, June through November; (13) the coastal
waters off Madagascar, July through September for humpback whale
breeding and November through December for migrating blue whales; (14)
Madagascar Plateau, Madagascar Ridge, and Walters Shoal, November
through December; (15) the Ligurian-Corsican-Provencal Basin and
Western Pelagos Sanctuary in the Mediterranean Sea, July to August;
(16) Hawaiian Islands Humpback Whale NMS and Penguin Bank, November
through April; (17) the Costa Rica Dome, year round; (18) the Great
Barrier Reef Between 16[deg] S and 21[deg] S, May through September;
(19) the Bonney Upwelling on the west coast of Australia, December
through May; (20) the Northern Bay of Bengal and Head of Swatch-of-No-
Ground, year round; (21) the Olympic Coast NMS (within 23 nmi (26.5 m;
42.6 km) of the coast from 47[deg]07' N to 48[deg]30' N latitude),
December, January, March, and May and the Prairie, Barkley Canyon, and
Nitnat Canyon, June through September; and (22) an area within the
Southern California Bight, June through November for blue whales,
December through May for gray whales, year-round for all other species.
The Navy agreed that these areas met NMFS' criteria and based on
its practicability assessment pursuant to the MMPA, the Navy proposed
21 of the 22 sites in its application. An area within the Southern
California Bight, specifically an area including Tanner and Cortes
Banks (see section 4.5.2.3 for boundary information) from June through
November, met the criteria as a concentrated area for blue whales based
on predictive modeling (Barlow et al., 2009) or as a foraging area
based on a 2000-2004 study of blue whale calls (Oleson, Calambokidis,
Barlow, & Hildebrand, 2007). However, the Navy concluded that the
underlying data cover a short time period and the dynamic nature of
blue whale distribution and the variability of prey abundance make it
difficult to assign any permanence to this area as one of blue whale
concentration. The Navy determined that avoiding this area was
operationally impracticable as much of the OBIA is within the existing
Southern California (SOCAL) Range Complex which plays a vital part in
ensuring military readiness. The training that occurs in the SOCAL
Range Complex includes antisubmarine warfare (ASW) training and the
SOCAL Range Complex provides the uneven, mountainous underwater
topography that is essential to such training, because it is similar to
the kind of underwater topography that submarines use to hide or mask
their presence. NMFS preliminarily concurs with the Navy's
practicability assessment.
Based on the Navy's practicability evaluation, NMFS proposes to
designate these 21 sites as OBIAs for LFA sonar. NMFS refers the
readers to Table 2 in the Navy's application and Chapter 4 and Appendix
D-8 of the Navy's 2011 DSEIS/SOEIS for more detailed information on the
specific justification for each OBIA, the locations, and geographic
boundaries of the proposed OBIAS.

NMFS' Additional 1-km Buffer Zone Around an OBIA Perimeter

NMFS also proposes an OBIA ``buffer'' requirement for the Navy that
would restrict the operation of SURTASS LFA sonar so that the SURTASS
LFA sonar sound field does not exceed 180 dB re: 1 [mu]Pa at a distance
of 1 km (0.62 mi; 0.54 nmi) seaward of the outer perimeter of any OBIA
designated for marine mammals during the specified period. The Navy
notes in its application that this additional mitigation is practicable
and it would adhere to this additional measure if required in the
proposed rule.
OBIAs are mitigation measures for SURTASS LFA sonar and are based
on the system's unique operating and physical characteristics and
should not be assumed to be appropriate for other activities.

Coastal Standoff Zone

The Navy has proposed to restrict SURTASS LFA sonar operations
within 22 km (13. mi; 11.8 nmi) of any coastline, including islands
such that the SURTASS LFA sonar-generated sound field will not exceed
180 dB re: 1 [mu]Pa (RL) at that distance.

Operational Exception

It may be necessary for SURTASS LFA transmissions to be at or above
180 dB re 1 [mu]Pa (rms) within the boundaries of the designated
SURTASS LFA sonar OBIAs, including operating within an OBIA, when: (1)
Operationally necessary to continue tracking an existing underwater
contact; or (2) operationally necessary to detect a new underwater
contact within the OBIA. This exception will not apply to routine
training and testing with the SURTASS LFA sonar systems.

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 proposed beyond
those that the applicant proposed. 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 LFA sonar or other activities expected to result in the take
of marine mammals (this goal may contribute to goal 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 LFA sonar or other activities expected to result
in the take of marine mammals (this goal may contribute to goal 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 LFA sonar or other activities expected to result in the take
of marine mammals (this goal may contribute to goal a,

[[Page 879]]

above, or to reducing the severity of harassment takes only).
(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 (i.e., shutdown in the LFA
mitigation and buffer zones).
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 together with the additional mitigation measures proposed by
NMFS provide the 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. NMFS provides further details in the following
section.
NMFS believes that the shutdown in the LFA sonar mitigation and
buffer zones, visual monitoring, passive acoustic monitoring, active
acoustic monitoring using HF/M3 sonar with ramp-up procedures, and
geographic restriction measures proposed will enable the Navy to: (1)
Avoid Level A harassment of marine mammals; (2) Minimize the numbers of
marine mammals exposed to SURTASS LFA sonar sound associated with TTS;
and (3) Minimize the numbers taken specifically during times of
important behaviors, such as feeding, migrating, calving, or breeding.
TTS: The LFA sonar signal is not expected to cause TTS at received
levels below 180 dB re: 1 [mu]Pa. In other words, the received level of
the LFA sonar signal at approximately 1 km (0.62 mi; 0.54 nmi) from the
vessel is 180 dB re: 1 [mu]Pa. Implementing an additional 1-km buffer
zone increases the shutdown zone to approximately 2 km (1.2 mi; 1.1
nmi) around the LFA sonar array and vessel will ensure that no marine
mammals are exposed to an SPL greater than about 174 dB re: 1 [mu]Pa.
The best information available indicates that effects from SPLs
less than 180 dB re: 1 [mu]Pa will be limited to short-term, Level B
behavioral Harassment affecting less than an average of 12 percent of
the stocks present in an operational area annually for most affected
species.
PTS/Injury: In the case of SURTASS LFA sonar operations, NMFS does
not expect marine mammals to be exposed to received sound levels that
are high enough or long enough in duration to result in PTS. The Navy's
standard protective measures indicate that they would ensure delay or
suspension of SURTASS LFA sonar transmissions if any of the three
monitoring programs detect a marine mammal entering the LFA mitigation
and/or buffer zones i.e., within approximately two km (1.2 mi; 1.1 nmi)
of the vessel. The proposed mitigation monitoring measures would allow
the Navy to avoid exposing marine mammals to received levels of SURTASS
LFA sonar or HF/M3 sonar sound that could result in injury (Level A
harassment).
Southall et al. (2007) proposed injury criteria for individual
marine mammals exposed to non-pulsed sound types, which included
discrete acoustic exposures from SURTASS LFA sonar. The proposed injury
criteria for cetaceans are sound pressure levels (SPL) of 230 dB re: 1
[mu]Pa and sound exposure levels (SEL) of 215 dB re: 1 [mu]Pa\2\-sec.
Taking into account an 18-dB adjustment for the longer LFA signal in
SEL units, the proposed injury criteria for cetaceans exposed to
SURTASS LFA sonar signals would result in an SEL of 197 dB re: 1
[mu]Pa\2\-sec (i.e., 215 - 18 = 197) (which converts to an SPL of
approximately 182 dB re: 1 [mu]Pa). The Navy's criterion for estimating
injury marine mammals is an SPL of 180 dB re: 1 [mu]Pa is lower than
the injury criteria proposed by Southall et al. (2007). Thus, the
probability of SURTASS LFA sonar transmissions (with mitigation)
causing PTS in marine mammals is considered unlikely.
The SPLs capable of potentially causing injury to an animal are
well within approximately 1 km (0.62 mi; 0.54 nm) of the ship.
Implementing a shutdown zone of approximately 2 km (1.2 mi; 1.1 nmi)
around the LFA sonar array and vessel will ensure that no marine
mammals are exposed to an SPL greater than about 174 dB re: 1 [mu]Pa.
This is significantly lower than the 180-dB re: 1 [mu]Pa used for other
acoustic projects for protecting marine mammals from injury.
Serious injury is unlikely to occur unless a marine mammal is well
within the 180-dB re: 1 [mu]Pa LFA sonar mitigation zone and close to
the source. The closer a mammal is to the vessel, the more likely the
Navy personnel will detect it by the three-part monitoring program
leading to the immediate suspension of SURTASS LFA sonar operations.
The Navy has operated SURTASS LFA sonar under NMFS regulations for
the last nine years without any reports of injury or death. The
evidence to date, including recent scientific reports and annual
monitoring reports, and nine-year's worth of conducting SURTASS LFA
operations further supports the conclusion that the potential for
serious injury to occur is minimal.

Proposed Research

The Navy sponsors significant research and monitoring projects for
marine living resources to study the potential effects of its
activities on marine mammals. These funding levels have increased in
recent years to $31 million in FY 2009 and $32 million in FY 2010 for
marine mammal research and monitoring activities at universities,
research institutions, federal laboratories, and private companies.
Navy-funded research has produced many peer-reviewed articles in
professional journals. This ongoing marine mammal research relates to
hearing and hearing sensitivity, auditory effects, dive and behavioral
response models, noise impacts, beaked whale global distribution,
modeling of beaked whale hearing and response, tagging of free-ranging
marine animals at-sea, and radar-based detection of marine mammals from
ships. The Navy sponsors 70 percent of all U.S. research on the effects
of human-generated underwater sound on marine mammals and 50 percent of
such research conducted worldwide. These research projects may not be
specifically related to SURTASS LFA sonar operations; however, they are
crucial to the overall knowledge base on marine mammals and the
potential effects from underwater anthropogenic noise. The Navy also
sponsors research to determine marine mammal abundances and densities
for all Navy ranges and other operational areas. The Navy notes that
research and evaluation is being carried out on various monitoring and
mitigation methods, including passive acoustic monitoring and the
results from this research could be applicable to SURTASS LFA sonar
passive acoustic monitoring. The Navy has also sponsored several
workshops to evaluate the current state of knowledge and potential for
future acoustic monitoring of marine mammals. The workshops bring
together underwater acoustic subject matter experts and marine
biologists from the Navy and

[[Page 880]]

other research organizations to present data and information on current
acoustic monitoring research efforts, and to evaluate the potential for
incorporating similar technology and methods on Navy instrumented
ranges.

Proposed 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 Sec. 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, 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:
(a) An increase in our understanding of how many marine mammals are
likely to be exposed to levels of LFA sonar that we associate with
specific adverse effects, such as behavioral harassment, TTS, or PTS.
(b) An increase in our understanding of how individual marine
mammals respond (behaviorally or physiologically) to LFA sonar (at
specific received levels or other stimuli expected to result in take.
(c) An increase in our understanding of how anticipated takes of
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).
(d) An increase in knowledge of the affected species.
(e) An increase in our understanding of the effectiveness of
certain mitigation and monitoring measures.
(f) A better understanding and record of the manner in which the
authorized entity complies with the incidental take authorization.
(g) An increase in the probability of detecting marine mammals,
both within the mitigation zone (thus allowing for more effective
implementation of the mitigation) and in general to better achieve the
above goals.

Marine Mammal Monitoring (M3) Program

The Marine Mammal Monitoring (M3) Program uses the Navy's permanent
seafloor sensor arrays in areas of the Atlantic Ocean to passively
monitor the movements of some large cetaceans, including their
migration and feeding patterns, by tracking them through their
vocalizations. Analysts can not only count numbers of whales, but in
some cases also note the interaction and influence of underwater noise
sources on the animals. Some whales are vocal enough to allow long-term
tracking; e.g., in 2010 a blue whale was tracked for 67 days. Recently,
upgraded acoustic signal processing systems have allowed for detection
of sperm whale clicks--longest holding to date of one sperm whale is 12
hrs, which included 14 dives. As previously noted these data are not
real time and thus cannot be relied upon for mitigation purposes. At
present, most of the data resulting from the M3 Program are classified.
The Navy will continue to assess the data collected by its undersea
arrays and work toward making some portion of that data, after
appropriate security reviews, available to scientists with appropriate
clearances. Any portions of the analyses conducted by these scientists
based on these data that are determined to be unclassified after
appropriate security reviews will be made publically available.

Passive Acoustic Monitoring With Fleet Exercises

For fleet exercises that SURTASS LFA sonar is involved in, the Navy
is exploring the feasibility of coordinating with other fleet assets
and/or range monitoring programs to include the use of SURTASS towed
horizontal line arrays to augment the collection of marine mammal
vocalizations before, during, and after designated exercises. The goal
would be to determine the extent, if any, of changes in marine mammal
vocalizations that could have been caused by SURTASS LFA sonar
operations during the exercise. This applies directly to increased
knowledge of marine mammal species. If the collection of such
calibrated and validated data can occur, this could be useful
information in NMFS' environmental compliance processes for underwater
LF sonar systems.
This effort would require detailed pre-planning and a comprehensive
data collection and analysis plan, which will necessarily be subject to
the fleet operations plan for the exercise itself. Other factors that
would need to be addressed include the following: Scheduling of assets;
budgetary constraints; potential for qualified, professional marine
mammal biologists to ride the SURTASS LFA sonar vessel during the data
collection efforts; security measures; de-conflicting any potential
behavioral responses of marine mammals in the fleet exercise area from
other underwater sound sources (e.g., MF active sonars) with potential
behavioral responses from SURTASS LFA sonar transmissions; and
accounting for other variables that may cause a change in marine
mammals' vocalization output. This would be a task for a scientific
team made up of marine biologists, LFA operators, and meteorological/
oceanographic experts.

Ambient Noise Data Monitoring

Several efforts (federal and academic) are underway to develop a
comprehensive ocean noise budget (i.e., an accounting of the relative
contributions of various underwater sources to the ocean noise field)
for the world's oceans that include both anthropogenic and natural
sources of noise. Ocean noise distributions and noise budgets are used
in marine mammal masking studies, habitat characterization, and marine
animal impact analyses.
The Navy will collect ambient noise data when the SURTASS passive
towed horizontal line array is deployed. The Navy is exploring the
feasibility of declassifying and archiving the ambient noise data for
incorporation into appropriate ocean noise budget efforts. Thus, the
SURTASS LFA sonar vessels could serve as ad hoc ships of opportunity
for monitoring data that could provide validation of marine mammal-
relevant global ocean noise budgets by supplying up-to-date
measurements of the underwater noise field in data-poor and/or littoral
areas not previously surveyed.

Past Monitoring

The Navy's Low Frequency Sound Scientific Research Program (LFS
SRP) in 1997 to 1998 provided insights to baleen whale responses to LFA
sonar signals. The Navy designed the three-year study to assess the
potential impacts of SURTASS LFA sonar on the behavior of low-frequency
hearing specialists specifically addressing three important behavioral
contexts for baleen whales: Feeding, migration, and breeding. The
results of the LFS SRP confirmed that some portion of the total number
of whales exposed to LFA sonar responded behaviorally by changing their
vocal activity, moving away from the source vessel, or both; but the
responses were short-lived (Clark et al., 2001) (see Potential Effects
of Behavioral Disturbance).

Adaptive Management

Our understanding of the potential effects of SURTASS LFA sonar on
marine mammals is continually evolving. Reflecting this, the Navy
proposes to include an adaptive

[[Page 881]]

management component within the framework of the scientific
underpinning of its 2011 SEIS/OEIS that supports its application. This
allows the Navy, in concert with NMFS, to consider, on a case-by-case
basis, new/revised peer-reviewed and published scientific data and
information from qualified and recognized sources within academia,
industry, and government/non-government organizations to determine
(with input regarding practicability) whether SURTASS LFA sonar
mitigation, monitoring, or reporting measures should be modified
(including additions or deletions); if new scientific data indicate
that such modifications would be appropriate. It also allows for
updates to marine mammal stock estimates to be included in annual LOA
applications, which, in turn, provides for the use of the best
available scientific data for predictive models, including AIM.

Proposed 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. There are several different
reporting requirements in these proposed regulations:

General Notification of Injured or Dead Marine Mammals

The Navy will systematically observe SURTASS LFA sonar operations
for injured or disabled marine mammals. In addition, the Navy will
monitor the principal marine mammal stranding networks and other media
to correlate analysis of any whale strandings that could potentially be
associated with SURTASS LFA sonar operations.
Navy personnel will ensure that NMFS is notified immediately or as
soon as clearance procedures allow if an injured, stranded, or dead
marine mammal is found during or shortly after, and in the vicinity of,
any SURTASS LFA operations. The Navy will 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).
In the event that an injured, stranded, or dead marine mammal is
found by the Navy that is not in the vicinity of, or found during or
shortly after SURTASS LFA sonar operations, the Navy will report the
same information as listed above as soon as operationally feasible and
clearance procedures allow.

General Notification of a Ship Strike

Because SURTASS LFA vessels move slowly, it is not likely these
vessels would strike a marine mammal. In the event of a ship strike by
the SURTASS LFA vessel, at any time or place, the Navy shall do the
following:
Immediately report to NMFS the species identification (if
known), location (lat/long) of the animal (or the strike if the animal
has disappeared), and whether the animal is alive or dead (or unknown);
Report to NMFS as soon as operationally feasible the size
and length of the animal, an estimate of the injury status (e.g., dead,
injured but alive, injured and moving, unknown, etc.), vessel class/
type and operational status;
Report to NMFS the vessel length, speed, and heading as
soon as feasible; and
Provide NMFS a photo or video, if equipment is available.

Long-Term Monitoring (LTM) Program Reports

During routine operations of SURTASS LFA sonar, the Navy will
collect and record technical and environmental data, which are part of
the Navy's LTM Program. These would include data from visual and
acoustic monitoring, ocean environmental measurements, and technical
operational inputs.

Quarterly Mitigation Monitoring Report

On a quarterly basis, the Navy would provide NMFS with classified
and unclassified reports that include all active-mode missions
completed 30 days or more prior to the date of the deadline for the
report. Specifically, these reports will include dates/times of
exercises, location of vessel, mission operational area, location of
the mitigation zone in relation to the LFA sonar array, marine mammal
observations, and records of any delays or suspensions of operations.
Marine mammal observations would include animal type and/or species,
number of animals sighted by species, date and time of observations,
type of detection (visual, passive acoustic, HF/M3 sonar), the animal's
bearing and range from vessel, behavior, and remarks/narrative (as
necessary). The report would include the Navy's analysis of whether any
Level A and/or Level B taking occurred within the SURTASS LFA sonar
mitigation zone and, if so, estimates of the percentage of marine
mammal stocks affected (both for the quarter and cumulatively (to date)
for the year covered by the LOA) by SURTASS LFA sonar operations. This
analysis would include estimates for both within and outside the LFA
sonar mitigation zone, using predictive modeling based on operating
locations, dates/times of operations, system characteristics,
oceanographic environmental conditions, and animal demographics. In the
event that no SURTASS LFA missions are completed during a quarter, the
Navy will provide NMFS with a report of negative activity.

Annual Report

The annual report, which is due no later than 45 days after the
expiration date of the LOAs, would provide NMFS with an unclassified
summary of the year's quarterly reports and will include the Navy's
analysis of whether any Level A and/or Level B taking occurred within
the SURTASS LFA sonar mitigation zones and, if so, estimates of the
percentage of marine mammal stocks affected by SURTASS LFA sonar
operations. This analysis would include estimates for both within and
outside the LFA sonar mitigation zones, using predictive modeling based
on operating locations, dates/times of operations, system
characteristics, oceanographic environmental conditions, and animal
demographics.
The annual report would also include: (1) Analysis of the
effectiveness of the mitigation measures with recommendations for
improvements where applicable; (2) assessment of any long-term effects
from SURTASS LFA sonar operations; and (3) any discernible or estimated
cumulative impacts from SURTASS LFA sonar operations.

Comprehensive Report

NMFS proposes to require the Navy to provide NMFS and the public
with a final comprehensive report analyzing the impacts of SURTASS LFA
sonar on marine mammal species and stocks. This report, which is due at
least 240 days prior to expiration of these regulations, would include
an in-depth analysis of all monitoring and Navy-funded research
pertinent to SURTASS LFA sonar operations conducted during the 5-year
period of these regulations, a scientific assessment of cumulative
impacts on marine mammal stocks, and an analysis on the advancement of
alternative (passive) technologies as a replacement for LFA sonar. This
report would be a key document for NMFS' review and assessment of
impacts for any future rulemaking.
The Navy shall respond to NMFS comments and requests for additional

[[Page 882]]

information or clarification on quarterly, annual or comprehensive
report. These reports will be considered final after the Navy has
adequately addressed NMFS' comments or provided the requested
information, or three months after the submittal of the draft if NMFS
does not comment within the three-month time period. NMFS will post the
annual and comprehensive reports on the Internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.

Estimated Take of Marine Mammals

As mentioned previously, one of the main purposes of NMFS' effects
assessments is to identify the permissible methods of taking, meaning:
the nature of the take (e.g., resulting from anthropogenic noise vs.
from ship strike, etc.); the regulatory level of take (i.e., mortality
vs. Level A or Level B harassment) and the amount of take. The
Potential Effects section identified the lethal responses, physical
trauma, sensory impairment (permanent and temporary threshold shifts
and acoustic masking), physiological responses (particular stress
responses), and behavioral responses that could potentially result from
exposure to SURTASS LFA sonar operations. This section will relate the
potential effects to marine mammals from SURTASS LFA sonar operations
to the MMPA statutory definitions of Level A and Level B Harassment and
attempt to quantify the effects that might occur from the specific
training activities that the Navy has proposed.
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, and other pertinent 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 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 in the previous
sections, 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 SURTASS LFA sonar or HF/M3 sonar (or another stressor), is
considered Level B Harassment. Louder sounds (when other factors are
not considered) are generally expected to elicit a stronger response
than softer sounds. Some of the lower level physiological stress
responses discussed in the previous sections will 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.
In the effects section above, 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 typically would not include behaviors ranked 0-3.
Acoustic Masking and Communication Impairment--The severity or
importance of an acoustic masking event can vary based on the length of
time that the masking occurs, the frequency of the masking signal
(which determines which sounds are masked, which may be of varying
importance to the animal), and other factors. Some acoustic masking
would be considered Level B Harassment, if it can disrupt natural
behavioral patterns by interrupting or limiting the marine mammal's
receipt or transmittal of important information or environmental cues.
TTS--As discussed previously, TTS can disrupt behavioral patterns
by inhibiting an animal's ability to communicate with conspecifics and
interpret other environmental cues important for predator avoidance and
prey capture. However, 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). 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 takes place during a time when
the animal is traveling through the open ocean, 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 a time when communication is critical for successful mother/calf
interactions could have more serious impacts if it was in the same
frequency band as the necessary vocalizations and of a severity that
impeded communication.
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) indicates that although PTS is a
tissue injury, TTS is not, because the reduced hearing sensitivity
following exposure to intense sound results primarily from

[[Page 883]]

fatigue, not loss, of cochlear hair cells and supporting structures and
is reversible. Accordingly, NMFS classifies TTS (when resulting from
exposure to either SURTASS LFA sonar or HF/M3 sonar) as Level B
Harassment, not Level A Harassment (injury).

Level A Harassment

Of the potential effects that were described in the previous
sections, the following are the types of effects that fall into the
Level A Harassment category:
PTS--PTS (resulting from either exposure to SURTASS LFA sonar or
HF/M3 sonar) 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. Although
PTS is considered an injury, the effects of PTS on the fitness of an
individual can vary based on the degree of TTS and its frequency band.
Tissue Damage due to Acoustically Mediated Bubble Growth--A few
theories suggest ways in which gas bubbles become enlarged through
exposure to intense sounds (SURTASS LFA sonar or HF/M3 sonar) 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 active sonar pings (such as that which an animal exposed to SURTASS
LFA sonar) 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 or, potentially, mortality.
Tissue Damage due to Behaviorally Mediated Bubble Growth--Several
authors suggest mechanisms in which marine mammals could behaviorally
respond to exposure to SURTASS LFA sonar or HF/M3 sonar by altering
their dive patterns in a manner (unusually rapid ascent, unusually long
series of surface dives, etc.) that might result in unusual bubble
formation or growth ultimately resulting in tissue damage (e.g.,
emboli). 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 the tissue effects observed from recent beaked
whale strandings are consistent with gas emboli and bubble-induced
tissue separations (Jepson et al., 2003; Fernandez et al., 2005; Tyack
et al., 2006), 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 or, potentially, mortality.

Estimates of Potential Marine Mammal Exposure

Estimating the take that will result from the proposed activities
begins with the CNO and fleet commands proposing mission areas to
operate SURTASS LFA sonar. The Navy analyzes the mission areas based on
current scientific data to determine the potential sensitivity of
marine mammals to SURTASS LFA sonar signals and risks to their stocks.
If marine mammal densities prove to be high and/or sensitive animal
activities are expected, the Navy changes/refines the mission areas to
areas with lower numbers of marine mammals, or lower levels of
biologically-sensitive marine mammal activities. Subsequently the
process is re-initiated for the modified mission area. Next, the Navy
performs standard acoustic modeling and risk analyses, taking into
account spatial, temporal, and/or operational restrictions. Then, the
Navy applies standard mitigation measures to the analysis to calculate
risk estimates for marine mammal stocks in the proposed mission area.
Based on these estimates, the Navy decides if the proposed mission area
meets the conditions of the MMPA regulations and LOAs, as issued, on
marine mammal/animal impacts from SURTASS LFA sonar. If not, the
proposed mission area is changed or refined, and the process is re-
initiated. If the mission area risk estimates are below the required
restrictions, then the Navy has identified and selected the potential
mission area with minimal marine mammal/animal activity consistent with
its operational readiness requirements and restrictions placed on LFA
operations by NMFS in the regulatory and consultation processes. This
sensitivity/risk assessment approach allows the Navy to determine where
and when SURTASS LFA sonar can operate and meet the MMPA condition for
the least practicable adverse impacts on marine mammals.
As described earlier (see Brief Background on the Navy's Assessment
of the Potential Impacts on Marine Mammals), the Navy assesses the
potential impacts on marine mammals predicting the sound field that a
given marine mammal species could be exposed to over time in a
potential operating area. This is a multi-part process involving: (1)
The ability to measure or estimate an animal's location in space and
time; (2) the ability to measure or estimate the three-dimensional
sound field at these times and locations; (3) the integration of these
two data sets into the AIM to estimate the total acoustic exposure for
each animal in the modeled population; (4) the conversion of the
resultant cumulative exposures for a modeled population into an
estimate of the risk from a significant disturbance of a biologically
important behavior; and (5) the use of a risk continuum to convert
these estimates of behavioral risk into an assessment of risk in terms
of the level of potential biological removal.
The Navy uses the LFA sonar mitigation zone to calculate estimates
for Level A harassment (injury). The area between the LFA sonar
mitigation zone and the 1-km (0.62 mi; 0.54 nmi) buffer zone (estimated
to extend to about the 174-dB isopleth) is an area where marine mammals
could experience Level B harassment. The Navy uses this area to
calculate estimates for Level B harassment using a risk continuum from
the 120 to 179-dB isopleth for marine mammals. Based on the Navy's AIM
modeling results, the primary effects would be the potential for Level
B Harassment. In addition, while possible, Level A harassment, if it
occurs at all, is expected to be so minimal as to have no effect on
rates of reproduction or survival of affected marine mammal species.
More information regarding the risk assessment methodology, the models
used, the assumptions used in the models, and the process of estimating
take is available in section 6.4 of the Navy's application and section
4.4 of the Navy's 2007 Final SEIS and section 4.4 of the Navy's DSEIS/
SOEIS.
Because it is infeasible to model enough representative sites to
cover all potential LFA operating areas, the Navy's application
presents 19 modeled sites as examples to provide estimates of potential
operating areas based on the current political climate. The Navy

[[Page 884]]

analyzed these 19 operating sites using the most up-to-date marine
mammal abundance, density, and behavioral information available. These
sites they represent, based on today's political climate, areas where
SURTASS LFA sonar could potentially test, train, or operate. Tables 9
through 27 provide the Navy's estimates of the number of marine mammals
potentially affected for SURTASS LFA sonar operations and are based on
reasonable and realistic estimates of the potential effects to marine
mammal stocks specific to the potential mission areas. These data are
examples of areas where the Navy could request LOAs under the 5-year
rule because they are in areas of potential strategic importance and/or
areas of possible naval fleet exercises. As stated previously, this
proposed rule does not specify the number of marine mammals that may be
taken in the proposed locations because these are determined annually
through various inputs such as mission location, mission duration, and
season of operation. For the annual application for an LOA, the Navy
proposes to present both the estimated percentage of stock incidentally
harassed as well as the estimated number of animals that may be
potentially harassed by SURTASS LFA sonar.
With the implementation of the three-part monitoring programs
(visual, passive acoustic, and HF/M3 monitoring), NMFS and the Navy do
not expect that marine mammals would be injured by SURTASS LFA sonar
because a marine mammal should be detected and active transmissions
suspended or delayed. As mentioned previously, the Navy determines
Level A harassments based on actual observations and/or detections
within the LFA sonar mitigation zone. The probability of detection of a
marine mammal by the HF/M3 system within the LFA sonar mitigation zone
approaches 100 percent based on multiple pings (see the 2001 FOEIS/EIS,
Subchapters 2.3.2.2 and 4.2.7.1 for the HF/M3 sonar testing results).
In the Navy's application, the Navy's acoustic analyses predict that
less than 0.0001 percent of the endangered north Pacific right whale
stock and 0.00 percent of the stocks of all other marine mammal species
may be exposed to levels of sound likely to result in Level A
harassment (i.e., exposures at 180 dB re: 1 [micro]Pa or greater).
Quantitatively, the Navy's request translates into take estimates of
zero animals for any species including the endangered north Pacific
right whale. However, because the probability of detection by the HF/M3
system within the LFA sonar mitigation zone is not 100 percent, NMFS
will include a small number of Level A harassment takes for marine
mammals over the course of the five-year regulations based on
qualitative analyses.
Reviewing the Navy's historical data on visual alerts that have
triggered a suspension of SURTASS LFA sonar transmission outside of the
LFA sonar mitigation zone, the data indicate that the largest grouping
of mysticetes that has triggered a shutdown outside of the LFA sonar
mitigation zone and within the buffer zone is three. Similarly, the
largest number of odontocetes that has triggered a shutdown is two.
Thus, NMFS analyzes the take of no more than six mysticetes (total),
across all species requested in the Navy's application by Level A
harassment; no more than 25 odontocetes (across all species) by Level A
harassment; and no more than 25 pinnipeds (across all species) by Level
A harassment over the course of the 5-year regulations. These are the
only quantitative adjustments that NMFS has made to the requested takes
from the Navy's modeled exposure results. Again, NMFS notes that over
the course of the previous two rulemakings, there have been no reported
incidents of Level A harassment of any marine mammal. As with the 2002
and 2007 Rules, the Navy will limit operation of LFA sonar to ensure no
marine mammal stock will be subject to more that 12 percent of takes by
Level B harassment annually, over the course of the five-year
regulations. This annual per-stock cap applies regardless of the number
of LFA vessels operating. The Navy will use the 12 percent cap to guide
its mission planning and annual LOA applications.

Analysis and Negligible Impact Preliminary Determination

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.'' In making a negligible impact determination,
NMFS considers:
(1) The number of anticipated mortalities;
(2) The number and nature of anticipated injuries;
(3) The number, nature, and intensity, and duration of Level B
harassment; and
(4) The context in which the takes occur.
As mentioned previously, NMFS estimates that 94 species of marine
mammals could be potentially affected by Level A or Level B harassment
over the course of the five-year period.
For reasons stated previously in this document, no mortalities are
anticipated to occur as a result of the Navy's proposed SURTASS LFA
operations, and none are proposed to be authorized by NMFS.
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 and the type of taking (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 (see Potential Effects of Behavioral Disturbance).
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. As mentioned previously, 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 has described its specified activities based on best
estimates of the number of hours that the Navy will conduct SURTASS LFA
operations. The exact number of transmission hours may vary from year
to year, but will not exceed the annual total indicated in Table 1.
Taking the above into account, considering the sections discussed
further, and dependent upon the implementation of the proposed
mitigation measures, NMFS has preliminarily determined that Navy

[[Page 885]]

training, testing, and military operations utilizing SURTASS LFA sonar
will have a negligible impact on the marine mammal species and stocks
present in operational areas in certain areas of the Pacific, Atlantic,
and Indian Oceans and the Mediterranean Sea.

Behavioral Harassment

As discussed in the Potential Effects of Exposure to SURTASS LFA
Sonar Operations, marine mammals may respond to SURTASS LFA sonar
operations 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 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 SURTASS LFA sonar operations, the Navy provided information
(Tables 24-42 of the Navy's application) estimating numbers of total
takes that could occur within the proposed operational areas. For
reasons stated previously in this document, the specified activities
associated with the proposed SURTASS LFA operations will most likely
fall within the realm of short-term, Level B behavioral harassment.
NMFS bases this assessment on a number of factors:
(1) Geographic Restrictions--With the implementation of geographic
restrictions on SURTASS LFA sonar operations, NMFS and the Navy have
minimized the likelihood of disruption of marine mammal behavior
patterns, such as migration, calving, breeding, feeding, or sheltering.
Because the coastal standoff and proposed OBIAs restrict the use of
SURTASS LFA sonar in known areas of feeding, calving, and breeding for
marine mammals, NMFS does not expect nor does it anticipate that
SURTASS LFA sonar operations likely will have adverse effects on annual
rates of recruitment or survival (i.e., population-level effects).
Also, the Navy's proposal to not conduct SURTASS LFA sonar
operations within 22 km (13. mi; 11.8 nmi) of any coastline, including
islands, to ensure that the sound field does not exceed 180 dB (i.e.,
LFA mitigation and buffer zones) offers protection to areas with higher
densities of marine mammals. Because the Navy will operate for the most
part in waters that are not areas known for high concentrations of
marine mammals, few, if any, marine mammals would be within the SURTASS
LFA mitigation and buffer zones.
(2) Low Frequency Sonar Scientific Research Program (LFS SRP)--
Based on the past nine years of SURTASS LFA sonar operations and the
LFS SRP, NMFS does not expect nor does it anticipate that SURTASS LFA
sonar operations will have likely adverse effects on annual rates of
recruitment or survival (i.e., population-level effects). The Navy
designed the three-year study to assess the potential impacts of
SURTASS LFA sonar on the behavior of low-frequency hearing specialists,
those species believed to be at (potentially) greatest risk. This field
research addressed three important behavioral contexts for baleen
whales: (1) Blue and fin whales feeding in the southern California
Bight, (2) gray whales migrating past the central California coast, and
(3) humpback whales breeding off Hawaii. Taken together, the results
from the three phases of the LFS SRP do not support the hypothesis that
most baleen whales exposed to RLs near 140 dB re: 1 [mu]Pa would
exhibit disturbance behavior and avoid the area. These experiments,
which exposed baleen whales to received levels ranging from 120 to
about 155 dB re: 1 [mu]Pa, detected only minor, short-term behavioral
responses. However, short-term behavioral responses do not necessarily
constitute significant changes in biologically important behaviors.
(3) Efficacy of the Navy's Three-Part Mitigation Monitoring
Program--From 2003 to 2010, the Navy reported a total of 12 visual
sightings, four passive acoustic detections, and 130 HF/M3 active sonar
detections of marine mammals, all leading to suspension/delays of
transmissions in accordance with mitigation protocols. Because the HF/
M3 active sonar is able to monitor large and medium marine mammals out
to an effective range of 2 to 2.5 km (1.2 to 1.5 mi; 1.1 to 1.3 nmi)
from the vessel, it is unlikely that the SURTASS LFA operations would
expose marine mammals to an SPL greater than about 174 dB re: 1 [mu]Pa
at 1 m. The area between the 180-dB LFA sonar mitigation zone and the
1-km (0.62 mi; 0.54 nm) buffer zone proposed by NMFS (estimated to
extend to about the 174-dB isopleth from the vessel) is an area where
marine mammals would experience Level B Harassment if exposed to LFA
sonar transmissions, in accordance with the Navy's risk analysis and
acoustic modeling (2001 FOEIS/EIS, Subchapter 4.2.3). Past results of
the HF/M3 sonar system tests provide confirmation that the system has a
demonstrated probability of single-ping detection of 95 percent or
greater for single marine mammals, 10 m (32.8 ft) in length or larger,
and a probability approaching 100 percent for multiple pings for any
sized marine mammal. Further, implementing a shutdown zone of
approximately 2 km (1.2 mi; 1.1 nmi) around the vessel will ensure that
no marine mammals are exposed to an SPL greater than about 174 dB re: 1
[mu]Pa at 1 m.

TTS

Schlundt et al. (2000) documented TTS in trained bottlenose
dolphins and belugas after exposure to intense 1-second signal duration
tones at 400 Hz, and 3, 10, 20, and 75 Hz. NMFS notes the LF-band tones
at 400 Hz at which the researchers were unable to induce TTS in any
animal at levels up to 193 dB re: 1 [mu]Pa at 1 m which was the maximum
level achievable with the equipment used in the experiment. The
researchers implied that the TTS threshold for a 100-second signal
would be approximately 184 dB (Table 1-4, 2001 FOEIS/EIS).
When SURTASS LFA sonar transmits, there is a boundary that encloses
a volume of water where received levels equal or exceed 180 dB (the
180-dB isopleth LFA sonar mitigation zone) and a volume of water
outside this boundary where received levels are below 180 dB (the 1 km
buffer encircling the 180-dB LFA sonar mitigation zone. The level of
risk for TTS for marine mammals depends on their location in relation
to SURTASS LFA sonar. Because the onset of PTS for marine mammals may
be 15-20 dB above TTS levels, one can assume that a marine mammal would
have to be within the 1 km buffer around the 180-dB LFA sonar
mitigation zone (i.e., modeled SPLs of 120-180 dB re: 1 [mu]Pa at 1 m)
to induce TTS. However, the Navy's standard protective measures
indicate that they would ensure delay or suspension of SURTASS LFA
sonar transmissions if any of the three monitoring programs detect a
marine mammal within 2 km (1.2 mi; 1.1 nmi) of the vessel. Thus, the
proposed mitigation measures would allow the Navy to reduce the number
of marine mammals exposed to received levels of SURTASS LFA sonar or
HF/M3 sonar sound that could result in TTS. For transient sounds, the
sound level necessary to cause TTS is inversely related to the duration
of the sound. Again, in the case of SURTASS LFA, animals are not
expected to be exposed

[[Page 886]]

to levels high enough or durations long enough to result in TTS. In
order to receive more than one ``ping'' during a normal vessel leg, an
animal would need to match the ship in speed and course direction
between pings. Because of the relatively short duty cycle, the water
depth of the convergence zone ray path, the movement of marine mammals
in relationship to the SURTASS LFA sonar ship, and the effectiveness of
the three-part mitigation program, few marine mammals are likely to be
affected by TTS (see Direct Physiological Effects--Threshold Shift
(Noise-Induced Loss of Hearing).

PTS

In NMFS' 2002 and 2007 rules, NMFS and the Navy based their
estimate of take by injury or the significant potential for such take
(Level A harassment) on the criterion of 180 dB. NMFS continues to
believe this is a scientifically supportable and conservative value for
preventing auditory injury or the significant potential for such injury
(Level A harassment), as it represents a value less than where the
potential onset of a minor TTS in hearing might occur based on Schlundt
et al.'s (2000) research (see the Navy's 2007 Final Comprehensive
Report Tables 5 through 8).
The Navy's standard protective measures indicate that they would
ensure delay or suspension of SURTASS LFA sonar transmissions if any of
the three monitoring programs detect a marine mammal either entering
the LFA sonar mitigation zone or buffer zones; (within approximately
two km (1.2 mi; 1.1 nmi)) of the LFA transmit array or vessel. The
proposed mitigation measures would allow the Navy to avoid exposing
marine mammals to received levels of SURTASS LFA sonar or HF/M3 sonar
sound that would result in injury (Level A harassment). The sound
pressure level (SPL) that is capable of potentially causing injury to
an animal is within approximately 1 km (0.62 mi; 0.54 nm) of the ship.
Implementing a shutdown zone of approximately 2 km (1.2 mi; 1.1 nmi)
around the LFA sonar array and vessel will ensure that no marine
mammals are exposed to an SPL greater than about 174 dB re: 1 [mu]Pa
(RL). This is significantly lower than the 180-dB re: 1 [mu]Pa (RL)
used for other acoustic projects for protecting marine mammals from
injury. Serious injury is unlikely to occur unless a marine mammal is
well within the 180-dB LFA sonar mitigation zone and close to the
source. The closer the mammal is to the vessel, the more likely it will
be detected by the tripartite monitoring program leading to the
immediate suspension of SURTASS LFA sonar transmissions.
With three levels of mitigation monitoring for detecting marine
mammals, NMFS believes it is unlikely that any marine mammal would be
exposed to received levels of 180 dB re: 1 [mu]Pa before being detected
and the SURTASS LFA sonar shut down. However, because the probability
is not zero, the Navy has requested Level A harassment takes incidental
to SURTASS LFA sonar operations.

Mortality

There is no empirical evidence of strandings of marine mammals
associated with the employment of SURTASS LFA sonar. Moreover, the
system acoustic characteristics differ between LF and MF sonars
associated with strandings: LFA sonars use frequencies generally below
1,000 Hz, with relatively long signals (pulses) on the order of 60 sec;
while MF sonars use frequencies greater than 1,000 Hz, with relatively
short signals on the order of 1 sec. NMFS has provided a summary of
common features shared by the strandings events in Greece (1996),
Bahamas (2000), Madeira (2000), Canary Islands (2002), Hanalei Bay
(2004), and Spain (2006) earlier in this document. These included
operation of MF sonar, deep water close to land (such as offshore
canyons), presence of an acoustic waveguide (surface duct conditions),
and periodic sequences of transient pulses (i.e., rapid onset and decay
times) generated at depths less than 32.8 ft (10 m) by sound sources
moving at speeds of 2.6 m/s (5.1 knots) or more during sonar operations
(D'Spain et al., 2006). None of these features relate to SURTASS LFA
sonar operations.
In summary (from the discussion above this section), NMFS has made
a preliminary finding that the total taking from SURTASS LFA activities
will have a negligible impact on the affected species or stocks based
on following: (1) The historical effectiveness of the Navy's three-part
monitoring program in detecting marine mammals and triggering
shutdowns, which make it unlikely that an animal will be exposed to
sound levels above 180 dB (i.e., levels potentially associated with
injury); (2) Geographic restrictions such as OBIAs and the coastal
standoff zone; (3) The requirement that the SURTASS LFA sonar sound
field not exceed 180 dB within 22 km of any shoreline, including
islands, or at a distance of one km from the perimeter of an OBIA; (4)
The fact that LF signals attenuate greatly in the near-surface zone,
where many of the marine mammals congregate for biologically-important
behaviors; (5) The small number of SURTASS LFA sonar systems that would
be operating world-wide; (6) The relatively low duty cycle, short
mission periods and offshore nature of the SURTASS LFA sonar; (7) The
fact that marine mammals in unspecified migration corridors and open
ocean concentrations would be adequately protected by the three-part
monitoring and mitigation protocols; and (8) Previous Endangered
Species Act consultation findings that that operation of the SURTASS
LFA sonar is not likely to jeopardize the continued existence of any
endangered or threatened species under the jurisdiction of NMFS or
result in the destruction or adverse modification of critical habitat.
Impacts to marine mammals are anticipated to be in the form of Level B
behavioral harassment, due to the brief duration and sporadic nature of
the SURTASS LFA sonar operations. Certain species may have a behavioral
reaction (e.g., increased swim speed, avoidance of the area, etc.) to
the sound emitted during the proposed activities. In conclusion, while
marine mammals will potentially be affected by the SURTASS LFA sonar
sounds, NMFS has preliminarily determined that these impacts will be
short-term and are not reasonably likely to adversely affect the
species or stock through effects on annual rates of recruitment or
survival.

Subsistence Harvest of Marine Mammals

Although the Navy will not operate SURTASS LFA sonar in the vast
majority of Arctic waters, the Navy may potentially operate LFA sonar
in the Gulf of Alaska, where subsistence uses of marine mammals occur.
Subsistence uses of marine mammals in the Gulf of Alaska include the
harvest of harbor seals and Steller sea lions along coastal and
inshore, including bay, areas of the gulf. As many as six Alaskan
Native groups subsistence hunt harbor seals in the Gulf of Alaska,
although the Dena'ina only occasionally hunt harbor seals, and four
Native groups hunt Steller sea lions, with the Southeastern Alaska
Native groups only occasionally harvesting Stellers (Wolfe et al.,
2009). Subsistence products that are derived from harbor seals and
Steller sea lions by these Alaskan Native groups include oil, meat, and
skins. Subsistence hunting of harbor seals and Steller sea lions is a
specialized activity among Alaska Native groups, with only 30 percent
and 3 percent of the surveyed native households hunting harbor seals
and Steller sea lions, respectively (Wolfe et al., 2009).

[[Page 887]]

Should the Navy operate SURTASS LFA sonar in the Gulf of Alaska,
sonar operation would adhere to the shutdown in the mitigation and
buffer zones, we well as established geographic restrictions, which
include the coastal standoff range (which dictates that the sound field
produced by the sonar must be below 180 dB re: 1 [mu]Pa at 1 m within
22 km (13. mi; 11.8 nmi) of any coastline) and exclusion from OBIAs.
Although there are peaks in harvest activity for both species, both
harbor seals and Steller sea lions are harvested year-round in the
coastal waters of the gulf. While it is impossible to predict the
future timing of the possible employment of SURTASS LFA sonar in the
Gulf of Alaska, regardless of the time of year the sonar may be
employed in the Gulf of Alaska, there should be no overlap in time or
space with subsistence hunts due to the geographic restrictions on the
sonar use (i.e., coastal standoff range and OBIA restrictions). These
restrictions will prevent the Navy from generating a sound field that
reaches the shallow coastal and inshore areas of the Gulf of Alaska
where harvest of the two pinniped species occurs. The possible
employment of SURTASS LFA sonar in the Gulf of Alaska will not cause
abandonment of any harvest/hunting locations, will not displace any
subsistence users, nor place physical barriers between marine mammals
and the hunters. No mortalities of marine mammals have been associated
with the employment of SURTASS LFA sonar and the Navy undertakes a
suite of mitigation measures whenever SURTASS LFA sonar is actively
transmitting. Therefore, NMFS has preliminarily determined that the
possible future employment of SURTASS LFA sonar will not lead to
unmitigable adverse impacts on the availability of marine mammal
species or stocks for subsistence uses in the Gulf of Alaska.
In August 2011, the Navy sent a letter to the Native Affairs and
Natural Resources Advisor, Alaska Command at Elmendorf Air Force base
requesting that they provide copies of the SURTASS LFA Sonar DSEIS/
SOEIS (DoN, 2011) to pertinent native groups that participate in
subsistence hunting in the Gulf of Alaska. To date, the Navy has not
received any requests from Alaskan tribes for government-to-government
consultation pursuant to Executive Order 13175. The Navy will continue
to keep the Alaskan tribes informed of the timeframes of any future
SURTASS LFA sonar exercises planned for the area.

Endangered Species Act

There are 15 marine mammal species under NMFS' jurisdiction that
are listed as endangered or threatened under the ESA with confirmed or
possible occurrence in potential operational areas for SURTASS LFA: the
blue, fin, sei humpback, bowhead, North Atlantic right, North Pacific
right, southern right, gray, and sperm whales, as well as the western
and eastern distinct population segments (DPS) of the Steller sea lion,
Mediterranean monk seal, Hawaiian monk seal, the eastern DPS of the
Steller sea lion; the Guadalupe fur seal and the southern DPS of the
spotted seal.
On October 4, 1999, the Navy submitted a Biological Assessment to
NMFS to initiate consultation under section 7 of the ESA for its
SURTASS LFA sonar activities. NMFS concluded consultation with the Navy
on this action on May 30, 2002. The conclusion of that consultation was
that operation of the SURTASS LFA sonar system for testing, training
and military operations and the issuance by NMFS of incidental take
authorizations for this activity are not likely to jeopardize the
continued existence of any endangered or threatened species under the
jurisdiction of NMFS. The Navy and NMFS conducted additional
consultations prior to issuance of the annual LOAs.
On June 9, 2006, the Navy submitted a Biological Assessment to NMFS
to initiate consultation under section 7 of the ESA for the 2007-2012
SURTASS LFA sonar activities and NMFS' authorization for incidental
take under the MMPA. NMFS concluded consultation with the Navy on this
action on August 17, 2007. The conclusion of that consultation was that
operation of the SURTASS LFA sonar system for testing, training and
military operations and the issuance by NMFS of MMPA incidental take
authorizations for this activity are not likely to jeopardize the
continued existence of any endangered or threatened species under the
jurisdiction of NMFS or result in the destruction or adverse
modification of critical habitat. As with the first rule, the Navy and
NMFS conducted additional consultations prior to issuance of the annual
LOAs.
The Navy will consult with NMFS pursuant to section 7 of the ESA,
and NMFS will also consult internally on the issuance of regulations
and LOAs under section 101(a)(5)(A) of the MMPA for SURTASS LFA sonar
activities. NMFS will conclude consultation with itself and the Navy
prior to making a determination on the issuance of the final rule and
LOAs.
The USFWS is responsible for regulating the take of the several
marine mammal species including the southern sea otter, polar bear,
walrus, West African manatee, Amazonian manatee, West Indian manatee,
and dugong. None of these species occur in geographic areas that
overlap with SURTASS LFA sonar operations. Therefore, the Navy has
determined that SURTASS LFA sonar training, testing, and military
operations will have no effect on the endangered or threatened species
or their critical habitat of the ESA-listed species under the
jurisdiction of the USFWS. Thus, no consultation with the USFWS
pursuant to Section 7 of the ESA will occur.

National Environmental Policy Act

NMFS has participated as a cooperating agency on the Navy's Draft
Supplemental Environmental Impact Statement/Supplemental Overseas
Environmental Impact Statement (DSEIS/SOEIS) for employment of SURTASS
LFA sonar, published on August 19, 2011. The Navy's DSEIS is posted on
the Navy's Web site at http://www.surtass-lfa-eis.com. NMFS intends to
adopt the Navy's Final SEIS/SOEIS, if adequate and appropriate. If the
Navy's Final SEIS/SOEIS 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

This action does not contain any collection of information
requirements for purposes of the Paperwork Reduction Act of 1980 (44
U.S.C. 3501 et seq.).
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 will be affected by this rulemaking, not a small governmental
jurisdiction, small

[[Page 888]]

organization, or small business, as defined by the RFA. Any
requirements imposed by a Letter of Authorization issued pursuant to
these regulations, and any monitoring or reporting requirements imposed
by these regulations, will 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, Indians, Labeling, Marine mammals,
Penalties, Reporting and recordkeeping requirements, Seafood,
Transportation.

Dated: December 22, 2011.
Samuel D. Rauch III,
Deputy Assistant Administrator for Regulatory Programs, National Marine
Fisheries Service.

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

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

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

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

Subparts T Through W [Added and Reserved]

2. Subparts T through W are added to part 218 and reserved.
3. Subpart X is added to part 218 to read as follows:
Subpart X--Taking and Importing of Marine Mammals; Navy Operations of
Surveillance Towed Array Sensor System Low Frequency Active (SURTASS
LFA) Sonar
Sec.
218.230 Specified activity.
218.231 Effective dates. [Reserved]
218.232 Permissible methods of taking.
218.233 Prohibitions.
218.234 Mitigation.
218.235 Requirements for monitoring.
218.236 Requirements for reporting.
218.237 Applications for Letters of Authorization.
218.238 Letters of Authorization.
218.239 Renewal of Letters of Authorization.
218.240 Modifications to Letters of Authorization.
218.241 Adaptive Management.

Subpart X--Taking and Importing of Marine Mammals; Navy Operations
of Surveillance Towed Array Sensor System Low Frequency Active
(SURTASS LFA) Sonar

Sec. 218.230 Specified activity.

Regulations in this subpart apply only to the incidental taking of
those marine mammal species specified in paragraph (b) of this section
by the U.S. Navy, Department of Defense, while engaged in the operation
of no more than four SURTASS LFA sonar systems conducting active sonar
operations in areas specified in paragraph (a) of this section. The
authorized activities, as specified in a Letter of Authorization issued
under Sec. Sec. 216.106 and 218.238 of this chapter, include the
transmission of low frequency sounds from the SURTASS LFA sonar system
and the transmission of high frequency sounds from the mitigation sonar
described in Sec. 218.234 during routine training and testing as well
as during military operations.
(a) The incidental take, by Level A and Level B harassment, of
marine mammals from the activity identified in this section may be
authorized in certain areas of the Pacific, Atlantic, and Indian Oceans
and the Mediterranean Sea, as specified in a Letter of Authorization.
(b) The incidental take, by Level A and Level B harassment, of
marine mammals from the activity identified in this section is limited
to the following species and species groups:
(1) Mysticetes--blue whale (Balaenoptera musculus), bowhead whale
(Balaena mysticetus), Bryde's whale (Balaenoptera edeni), fin whale
(Balaenoptera physalus), gray whale (Eschrichtius robustus), humpback
whale (Megaptera novaeangliae), minke whale (Balaenoptera
acutorostrata), North Atlantic right whale (Eubalaena glacialis), North
Pacific right whale (Eubalena japonica), pygmy right whale (Capera
marginata), sei whale (Balaenoptera borealis), southern right whale
(Eubalaena australis),
(2) Odontocetes--Andrew's beaked whale (Mesoplodon bowdoini),
Arnoux's beaked whale (Berardius arnuxii), Atlantic spotted dolphin
(Stenella frontalis), Atlantic white-sided dolphin (Lagenorhynchus
acutus), Baird's beaked whale (Berardius bairdii), Beluga whale
(Dephinapterus leucas), Blainville's beaked whale (Mesoplodon
densirostris), Chilean dolphin (Cephalorhynchus eutropia), Clymene
dolphin (Stenella clymene), Commerson's dolphin (Cephalorhynchus
commersonii), common bottlenose dolphin (Tursiops truncatus), Cuvier's
beaked whale (Ziphius cavirostris), Dall's porpoise (Phocoenoides
dalli), Dusky dolphin (Lagenorhynchus obscurus), dwarf sperm and pygmy
sperm whales (Kogia simus and K. breviceps), false killer whale
(Pseudorca crassidens), Fraser's dolphin (Lagenodelphis hosei),
Gervais' beaked whale (Mesoplodon europaeus), ginkgo-toothed beaked
whale (Mesoplodon ginkgodens), Gray's beaked whale (Mesoplodon grayi),
Heaviside's dolphin (Cephalorhynchus heavisidii), Hector's beaked whale
(Mesoplodon hectori), Hector's dolphin (Cephalorhynchus hectori),
Hourglass dolphin (Lagenorhynchus cruciger), Hubbs' beaked whale
(Mesoplodon carhubbsi), harbor porpoise (Phocoena phocoena), killer
whale (Orca orcinus), long-beaked common dolphin (Delphinus capensis),
long-finned pilot whale (Globicephala melas), Longman's beaked whale
(Indopacetus pacificus), melon-headed whale (Peponocephala electra),
northern bottlenose whale (Hyperodon ampullatus), northern right whale
dolphin (Lissodelphis borealis), Pacific white-sided dolphin
(Lagenorhynchus obliquidens), pantropical spotted dolphin (Stenella
attenuata), Peale's dolphin (Lagenorhynchus australis), Perrin's beaked
whale (Mesoplodon perrini), pygmy beaked whale (Mesoplodon peruvianus),
pygmy killer whale (Feresa attenuata), Risso's dolphin (Grampus
griseus), rough-toothed dolphin (Steno bredanensis), Shepherd's beaked
whale (Tasmacetus sheperdii), short-beaked common dolphin (Delphinus
delphis), short-finned pilot whale (Globicephala macrorhynchus),
southern bottlenose whale (Hyperodon planifrons), southern right whale
dolphin (Lissodelphis peronii), Sowerby's beaked whale (Mesoplodon
bidens), spade-toothed beaked whale (Mesoplodon traversii), spectacled
porpoise (Phocoena dioptrica), sperm whale (Physeter macrocephalus),
spinner dolphin (Stenella longirostris), Stejneger's beaked whale
(Mesoplodon stejnegeri), strap-toothed beaked whale (Mesoplodon
layardii), striped dolphin (Stenella coeruleoalba), True's beaked whale
(Mesoplodon mirus), white-beaked dolphin (Lagenorhynchus albirostris),
(3) Pinnipeds--Australian sea lion (Neophoca cinerea), California
sea lion (Zalophus californianus), Galapagos fur seal (Arctocephalus
galapagoensis), Galapagos sea lion (Zalophus wollebaeki), gray seal
(Halichoerus grypus), Guadalupe fur seal (Arctocephalus townsendi),
harbor seal (Phoca vitulina), harp seal (Pagophilus

[[Page 889]]

groenlandicus), Hawaiian monk seal (Monachus schauinslandi), hooded
seal (Cystophora cristata), Juan Fernadez fur seal (Arctocephalus
philippi), Mediterranean monk seal (Monachus monachus), New Zealand fur
seal (Arctocephalus forsteri), New Zealand fur seal (Phocarctos
hookeri), northern elephant seal (Mirounga angustirostris), northern
fur seal (Callorhinus ursinus), ribbon seal (Phoca fasciata), South
African and Australian fur seals (Arctocephalus pusillus), South
American fur seal (Arctocephalus australis), South American sea lion
(Otaria flavescens), southern elephant seal (Mirounga leonina), spotted
seal (Phoca largha), Steller sea lion (Eumetopias jubatus),
subantarctic fur seal (Arctocephalus tropicalis).

Sec. 218.231 Effective dates. [Reserved]

Sec. 218.232 Permissible methods of taking.

(a) Under Letters of Authorization issued pursuant to Sec. Sec.
216.106 and 218.238 of this chapter, the Holder of the Letter of
Authorization may incidentally, but not intentionally, take marine
mammals by Level A and Level B harassment within the areas described in
Sec. 218.230(a), provided that the activity is in compliance with all
terms, conditions, and requirements of this subpart and the appropriate
Letter of Authorization.
(b) The Holder of the Letter of Authorization must conduct the
activities identified in Sec. 218.230 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. 218.230 is limited to the species listed in Sec.
218.230(b) by the method of take indicated in paragraphs (c)(2),
(c)(3), (c)(4), and (c)(5) of this section.
(1) The Navy must maintain a running calculation/estimation of
takes of each species over the effective period of this subpart.
(2) Level B Harassment will not exceed 12 percent of any marine
mammal stock listed in Sec. 218.230(b)(1) through (3) annually over
the course of the five-year regulations. This annual per-stock cap of
12 percent applies regardless of the number of LFA vessels operating.
(3) Level A harassment of no more than six mysticetes (total), of
any of the species listed in Sec. 218.230(b)(1) over the course of the
five-year regulations.
(4) Level A harassment of no more than 25 odontocetes (total), of
any of the species listed in Sec. 218.230(b)(2) over the course of the
five-year regulations.
(5) Level A harassment of no more than 25 pinnipeds (total), of any
of the species listed in Sec. 218.230(b)(3) over the course of the
five-year regulations.

Sec. 218.233 Prohibitions.

No person in connection with the activities described in Sec.
218.230 may:
(a) Take any marine mammal not specified in Sec. 218.230(b);
(b) Take any marine mammal specified in Sec. 218.230 other than by
incidental take as specified in Sec. 218.232(c)(2), (c)(3), (c)(4),
and (c)(5);
(c) Take any marine mammal specified in Sec. 218.230 if NMFS makes
a determination that 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, any of the terms, conditions,
or requirements of this subpart or a Letter of Authorization issued
under Sec. 216.106 and 218.238 of this chapter.

Sec. 218.234 Mitigation.

The Navy must conduct the activity identified in Sec. 218.230 in a
manner that minimizes, to the greatest extent practicable, adverse
impacts on marine mammals and their habitats. When conducting
operations identified in Sec. 218.230, the mitigation measures
described in this section and in any Letter of Authorization issued
under Sec. 216.106 and Sec. 218.238 of this chapter must be
implemented.
(a) Personnel Training--Lookouts: (1) The Navy shall train the
lookouts in the most effective means to ensure quick and effective
communication within the command structure in order to facilitate
implementation of protective measures if they spot marine mammals.
(2) The Navy will hire one or more marine mammal biologist
qualified in conducting at-sea marine mammal visual monitoring from
surface vessels to train and qualify designated ship personnel to
conduct at-sea visual monitoring.
(b) General Operating Procedures: (1) Prior to SURTASS LFA sonar
operations, the Navy will promulgate executive guidance for the
administration, execution, and compliance with the environmental
regulations under this subpart and Letters of Authorization.
(2) The Holder of a Letter of Authorization will not transmit the
SURTASS LFA sonar signal at a frequency greater than 500 Hz.
(c) LFA Mitigation Zone and 1-km Buffer Zone: (1) Prior to
commencing and during SURTASS LFA sonar transmissions, the Holder of a
Letter of Authorization will determine the propagation of LFA sonar
signals in the ocean and the distance from the SURTASS LFA sonar source
to the 180-decibel (dB) re: 1 [mu]Pa isopleth.
(2) The Holder of a Letter of Authorization will establish an 180-
dB LFA mitigation zone around the surveillance vessel that is equal in
size to the 180-dB re: 1 [mu]Pa isopleth (i.e., the area subjected to
sound pressure levels of 180 dB or greater) as well as a one-kilometer
(1-km) buffer zone around the LFA mitigation zone. If a marine mammal
is detected, through monitoring required under Sec. 218.235, within or
about to enter the LFA mitigation zone plus the 1-km buffer zone, the
Holder of the Authorization will immediately delay or suspend SURTASS
LFA sonar transmissions.
(d) Resumption of SURTASS LFA sonar transmissions: (1) The Holder
of a Letter of Authorization will not resume SURTASS LFA sonar
transmissions earlier than 15 minutes after:
(i) All marine mammals have left the area of the LFA mitigation and
buffer zones; and
(ii) There is no further detection of any marine mammal within the
LFA mitigation and buffer zones as determined by the visual, passive,
and high frequency monitoring described in Sec. 218.235.
(2) [Reserved].
(e) Ramp-up procedures for the high-frequency marine mammal
monitoring (HF/M3) sonar required under Sec. 218.235: (1) The Holder
of a Letter of Authorization will ramp up the HF/M3 sonar power level
beginning at a maximum source sound pressure level of 180 dB: re 1
[mu]Pa at 1 meter in 10-dB increments to operating levels over a period
of no less than five minutes:
(i) At least 30 minutes prior to any SURTASS LFA sonar
transmissions;
(ii) Prior to any SURTASS LFA sonar calibrations or testing that
are not part of regular SURTASS LFA sonar transmissions described in
Sec. 218.230; and
(iii) Anytime after the HF/M3 source has been powered down for more
than two minutes.
(2) The Holder of a Letter of Authorization will not increase the
HF/M3 sound pressure level once a marine mammal is detected; ramp-up
may resume once marine mammals are no longer detected.
(f) Geographic Restrictions on the SURTASS LFA Sonar Sound Field:
(1) The Holder of a Letter of Authorization will not operate the
SURTASS LFA sonar such that:
(i) The SURTASS LFA sonar sound field exceeds 180 dB re: 1 [mu]Pa
(rms) at a distance less than 12 nautical miles

[[Page 890]]

(nmi) (22 kilometers (km)) from any coastline, including offshore
islands;
(ii) The SURTASS LFA sonar sound field exceeds 180 dB re: 1 [mu]Pa
(rms) at a distance less than 1 km (0.5 nm) seaward of the outer
perimeter of any offshore biologically important area designated in
Sec. 218.234(f)(1)(iii) during the period specified.
(iii) Offshore Biologically Important Areas (OBIAs) for marine
mammals (with specified periods) for SURTASS LFA sonar operations
include the following:

------------------------------------------------------------------------
Name of area Location of area Months of importance
------------------------------------------------------------------------
Georges Bank................ 40[deg]00' N, Year-round.
72[deg]30' W.
39[deg]37' N,
72[deg]09' W.
39[deg]54' N,
71[deg]43' W.
40[deg]02' N,
71[deg]20' W.
40[deg]08' N,
71[deg]01' W.
40[deg]04' N,
70[deg]44' W.
40[deg]00' N,
69[deg]24' W.
40[deg]16' N,
68[deg]27' W.
40[deg]34' N,
67[deg]13' W.
41[deg]00' N,
66[deg]24' W.
41[deg]52' N,
65[deg]47' W.
42[deg]20' N,
66[deg]06' W.
42[deg]18' N,
67[deg]23' W.
Roseway Basin Right Whale 43[deg]05' N, June through
Conservation Area. 65[deg]40'. December, annually.
43[deg]05' N,
65[deg]03' W..
42[deg]45' N,
65[deg]40' W..
42[deg]45' N,
65[deg]03' W..
Great South Channel, U.S. 41[deg]00.000' N, January 1 to
Gulf of Maine, and 69[deg]05.000' W. November 14,
Stellwagen Bank National 42[deg]09.000' N, annually.
Marine Sanctuary (NMS). 67[deg]08.400' W..
42[deg]53.436' N,
67[deg]43.873' W..
44[deg]12.541' N,
67[deg]16.847' W..
44[deg]14.911' N,
67[deg]08.936' W..
44[deg]21.538' N,
67[deg]03.663' W..
44[deg]26.736' N,
67[deg]09.596' W..
44[deg]16.805' N,
67[deg]27.394' W..
44[deg]11.118' N,
67[deg]56.398' W..
43[deg]59.240' N,
68[deg]08.263' W..
43[deg]36.800' N,
68[deg]46.496' W..
43[deg]33.925' N,
69[deg]19.455' W..
43[deg]32.008' N,
69[deg]44.504' W..
43[deg]21.922' N,
70[deg]06.257' W..
43[deg]04.084' N,
70[deg]21.418' W..
42[deg]51.982' N,
70[deg]31.965' W..
42[deg]45.187' N,
70[deg]23.396' W..
42[deg]39.068' N,
70[deg]30.188' W..
42[deg]32.892' N,
70[deg]35.873' W..
42[deg]07.748' N,
70[deg]28.257' W..
42[deg]05.592' N,
70[deg]02.136' W..
42[deg]03.664' N,
69[deg]44.000' W..
41[deg]40.000' N,
69[deg]45.000' W..
Southeastern U.S. Right Critical Habitat November 15 to
Whale Seasonal Habitat. Boundaries are January 15,
coastal waters annually.
between 31[deg]15'
N and 30[deg]15' N
from the coast out
15 nautical miles
(nmi); and the
coastal waters
between 30[deg]15'
N and 28[deg]00' N
from the coast out
5 nmi. (50 CFR Sec.
226.13(c)).
OBIA Boundaries are
coastal waters
between 31[deg]15'
N and 30[deg]15' N
from 12 to 15 nmi.
North Pacific Right Whale 57[deg]03' N, March through
Critical Habitat. 153[deg]00' W. August, annually.
57[deg]18' N,
151[deg]30' W.
57[deg]00' N,
151[deg]30' W.
56[deg]45' N,
153[deg]00' W.
(50 CFR Sec.
226.215).
Silver Bank and Navidad Bank Silver Bank......... December through
20[deg]38.899 N, April, annually.
69[deg]23.640' W.
20[deg]55.706' N,
69[deg]57.984' W.
20[deg]25.221' N,
70[deg]00.387' W.
20[deg]12.833' N,
69[deg]40.604' W.
20[deg]13.918' N,
69[deg]31.518' W.
20[deg]28.680' N,
69[deg]31.900' W.
Navidad Bank:.......
20[deg]15.596' N,
68[deg]47.967' W.
20[deg]11.971' N,
68[deg]54.810' W.
19[deg]52.514' N,
69[deg]00.443' W.
19[deg]54.957' N,
68[deg]51.430' W.
19[deg]51.513' N,
68[deg]41.399' W.

[[Page 891]]

Coastal waters of Gabon, An exclusion zone June through
Congo and Equatorial Guinea. following the 500-m October.
isobath extending
from 3[deg]31.055'
N, 9[deg]12.226' E
in the north
offshore of Malabo
southward to
8[deg]57.470' S,
12[deg]55.873' E
offshore of Luanda.
Patagonian Shelf Break...... Between 200- and Year-round.
2000-m isobaths and
the following
latitudes:
35[deg]00' S,
39[deg]00' S,
40[deg]40' S,
42[deg]30' S,
46[deg]00' S,
48[deg]50' S.
Southern Right Whale Coastal waters May through
Seasonal Habitat. between 42[deg]00' December, annually.
S and 43[deg]00' S
from 12 to 15 nmi
including the
enclosed bays of
Golfo Nuevo, Golfo
San Jose and San
Matias. Golfos San
Jose and San Nuevo
are within 22 km
(12 nmi) coastal
exclusion zone.
Central California National Single stratum June through
Marine Sanctuaries. boundary created November, annually.
from the Cordell
Bank (15 CFR
922.10), Gulf of
the Farallones (15
CFR 922.80), and
Monterey Bay (15
CFR 922.30) NMS
legal boundaries.
Monterey Bay NMS
includes the
Davidson Seamount
Management Zone.
Antarctic Convergence Zone.. 30[deg] E to 80[deg] October through
E, 45[deg] S. March, annually.
80[deg] E to
150[deg] E, 55[deg]
S..
150[deg] E to
50[deg] W, 60[deg]
S.
50[deg] W to 30[deg]
E, 50[deg] S.
Piltun and Chayvo offshore 54[deg]09.436' N, June through
feeding grounds in the Sea 143[deg]47.408' W. November, annually.
of Okhotsk. 54[deg]09.436' N,
143[deg]17.354' W..
54[deg]01.161' N,
143[deg]17.354' W.
53[deg]53.580' N,
143[deg]13.398' W.
53[deg]26.963' N,
143[deg]28.230' W.
53[deg]07.013' N,
143[deg]35.481' W.
52[deg]48.705' N,
143[deg]38.447' W.
52[deg]32.077' N,
143[deg]37.788' W.
52[deg]21.605' N,
143[deg]34.163' W.
52[deg]09.470' N,
143[deg]26.582' W.
51[deg]57.686' N,
143[deg]30.208' W.
51[deg]36.033' N,
143[deg]42.794' W.
51[deg]08.082' N,
143[deg]51.301' W.
51[deg]08.082' N,
144[deg]16.742' W.
51[deg]24.514' N,
144[deg]11.139' W.
51[deg]48.116' N,
144[deg]10.809' W.
52[deg]03.194' N,
144[deg]20.363' W.
52[deg]23.235' N,
144[deg]10.150' W.
52[deg]28.674' N,
144[deg]12.787' W.
52[deg]42.523' N,
144[deg]10.150' W.
53[deg]12.972' N,
143[deg]55.648' W.
53[deg]18.505' N,
143[deg]56.637' W.
53[deg]23.041' N,
143[deg]53.011' W.
53[deg]28.250' N,
143[deg]53.341' W.
53[deg]44.039' N,
143[deg]49.056' W.
53[deg]53.207' N,
143[deg]50.045' W.
53[deg]59.819' N,
143[deg]48.067' W.
Coastal waters off 16[deg]03'55.04'' S, July through
Madagascar. 50[deg]27'12.59'' E. September, annually
16[deg]12'23.03'' S, for humpback whale
51[deg]03'37.38'' breeding and
E.. November through
24[deg]30'45.06'' S, December, annually
48[deg]26'00.94'' for migrating blue
E.. whales.
24[deg]15'28.07'' S,
47[deg]46'51.16''
E..
22[deg]18'00.74'' S,
48[deg]14'13.52''
E..
20[deg]52'24.12'' S,
48[deg]43'13.49''
E..
19[deg]22'33.24'' S,
49[deg]15'45.47''
E..
18[deg]29'46.08'' S,
49[deg]37'32.25''
E..
17[deg]38'27.89'' S,
49[deg]44'27.17''
E..
17[deg]24'39.12'' S,
49[deg]39'17.03''
E..
17[deg]19'35.34'' S,
49[deg]54'23.82''
E..
16[deg]45'41.71'' S,
50[deg]15'56.35''
E..
Madagascar Plateau, 25[deg]55'20.00'' S, November through
Madagascar Ridge, and 44[deg]05'15.45'' E. December, annually.
Walters Shoal. 25[deg]46'31.36'' S,
47[deg]22'35.90''
E..
27[deg]02'37.71'' S,
48[deg]03'31.08'' E.
35[deg]13'51.37'' S,
46[deg]26'19.98'' E.
35[deg]14'28.59'' S,
42[deg]35'49.20'' E.
31[deg]36'57.96'' S,
42[deg]37'49.35'' E.
27[deg]41'11.21'' S,
44[deg]30'11.01'' E.
Ligurian-Corsican-Provencal 42[deg]50.271' N, July to August,
Basin and Western Pelagos 06[deg]31.883' E. annually.
Sanctuary in the 42[deg]55.603' N,
Mediterranean Sea. 06[deg]43.418' E..
43[deg]04.374' N,
06[deg]52.165' E..
43[deg]12.600' N,
07[deg]10.440' E.

[[Page 892]]

43[deg]21.720' N,
07[deg]19.380' E.
43[deg]30.600' N,
07[deg]32.220' E.
43[deg]33.900' N,
07[deg]49.920' E.
43[deg]36.420' N,
08[deg]05.580' E.
43[deg]42.600' N,
08[deg]22.140' E.
43[deg]50.880' N,
08[deg]34.500' E.
43[deg]58.560' N,
08[deg]47.700' E.
43[deg]59.040' N,
08[deg]56.040' E.
43[deg]57.047' N,
09[deg]03.540' E.
43[deg]52.260' N,
09[deg]08.520' E.
43[deg]47.580' N,
09[deg]13.500' E.
43[deg]36.060' N,
09[deg]16.620' E.
43[deg]28.440' N,
09[deg]05.820' E.
43[deg]21.360' N,
09[deg]02.100' E.
43[deg]16.020' N,
08[deg]57.240' E.
43[deg]04.440' N,
08[deg]47.580' E.
42[deg]54.900' N,
08[deg]35.400' E.
42[deg]45.900' N,
08[deg]27.540' E.
42[deg]36.060' N,
08[deg]22.020' E.
42[deg]22.620' N,
08[deg]15.849' E.
42[deg]07.202' N,
08[deg]17.174' E.
41[deg]52.800' N,
08[deg]15.720' E.
41[deg]39.780' N,
08[deg]05.280' E.
41[deg]28.200' N,
08[deg]51.600' E.
42[deg]57.060' N,
06[deg]19.860' E.
Hawaiian Islands Humpback 21[deg]10'02.179'' November through
Whale NMS and Penguin Bank. N, April, annually.
157[deg]30'58.217''
W.
21[deg]09'46.815''
N,
157[deg]30'22.367''
W..
21[deg]06'39.882''
N,
157[deg]31'00.778''
W..
21[deg]02'51.976''
N,
157[deg]30'30.049''
W..
20[deg]59'52.725''
N,
157[deg]29'28.591''
W..
20[deg]58'05.174''
N,
157[deg]27'35.919''
W..
20[deg]55'49.456''
N,
157[deg]30'58.217''
W..
20[deg]50'44.729''
N,
157[deg]42'42.418''
W..
20[deg]51'02.654''
N,
157[deg]44'45.333''
W..
20[deg]53'56.784''
N,
157[deg]46'04.716''
W..
20[deg]56'32.988''
N,
157[deg]45'33.987''
W..
21[deg]01'27.472''
N,
157[deg]43'10.586''
W..
21[deg]05'20.499''
N,
157[deg]39'27.802''
W..
21[deg]10'02.179''
N,
157[deg]30'58.217''
W..
Costa Rica Dome............. Centered at 9[deg] N Year-round.
and 88[deg] W.
Great Barrier Reef Between 16[deg]01.829' S, May through
16[deg] S and 21[deg] S. 145[deg]38.783' E. September,
15[deg]52.215' S, annually.
146[deg]20.936' E..
17[deg]28.354' S,
146[deg]59.392' E..
20[deg]16.228' S,
151[deg]39.674' E.
20[deg]58.381' S,
150[deg]30.897' E.
20[deg]17.007' S,
149[deg]38.247' E.
20[deg]10.941' S,
149[deg]18.247' E.
20[deg]02.403' S,
149[deg]12.623' E.
19[deg]53.287' S,
149[deg]03.986' E.
19[deg]49.866' S,
148[deg]52.135' E.
19[deg]53.287' S,
148[deg]44.302' E.
19[deg]47.965' S,
148[deg]36.870' E.
19[deg]47.205' S,
148[deg]26.024' E.
19[deg]19.978' S,
147[deg]39.626' E.
19[deg]14.065' S,
147[deg]37.014' E.
19[deg]08.913' S,
147[deg]31.993' E.
19[deg]05.667' S,
147[deg]24.160' E.
19[deg]07.576' S,
147[deg]18.134' E.
18[deg]51.718' S,
146[deg]51.219' E.
18[deg]44.258' S,
146[deg]54.031' E.
18[deg]37.175' S,
146[deg]51.420' E.
18[deg]31.620' S,
146[deg]43.385' E.
18[deg]27.595' S,
146[deg]40.573' E.
17[deg]36.676' S,
146[deg]20.488' E.
17[deg]20.484' S,
146[deg]16.671' E.
17[deg]07.745' S,
146[deg]13.056' E.
16[deg]49.769' S,
146[deg]11.047' E.
16[deg]41.835' S,
146[deg]03.817' E.
16[deg]39.706' S,
145[deg]54.979' E.
Bonney Upwelling on the west 37[deg]12'20.036'' December through
coast of Australia. S, May, annually.
139[deg]31'17.703''
E.
37[deg]37'33.815''
S,
139[deg]42'42.508''
E..
38[deg]10'36.144''
S,
140[deg]22'57.345''
E..
38[deg]44'50.558''
S,
141[deg]33'50.342''
E.
39[deg]07'04.125''
S,
141[deg]11'00.733''
E.

[[Page 893]]

37[deg]28'33.179''
S,
139[deg]10'52.263''
E.
Northern Bay of Bengal and 20[deg]59.735' N, Year-round.
Head of Swatch-of-No-Ground. 89[deg]07.675' E.
20[deg]55.494' N,
89[deg]09.484' E..
20[deg]52.883' N,
89[deg]12.704' E..
20[deg]55.275' N,
89[deg]18.133' E..
21[deg]04.558' N,
89[deg]25.294' E..
21[deg]12.655' N,
89[deg]25.354' E..
21[deg]13.279' N,
89[deg]16.833' E..
21[deg]06.347' N,
89[deg]15.011' E..
Olympic Coast NMS and Boundaries within 23 Olympic NMS:
Prairie, Barkley Canyon, nmi (26.5 m; 42.6 December, January,
and Nitnat Canyon. km) of the coast March, and May.
from 47[deg]07' N
to 48[deg]30' N
latitude.
48[deg]30'01.995'' Prairie, Barkley
N, Canyon, and Nitnat
125[deg]58'38.786'' Canyon: June
W. through September.
48[deg]16'55.605''
N,
125[deg]38'52.052''
W..
48[deg]23'07.353''
N,
125[deg]17'10.935''
W..
48[deg]12'38.241''
N,
125[deg]16'42.339''
W..
47[deg]58'20.361''
N,
125[deg]31'14.517''
W..
47[deg]58'20.361''
N,
126[deg]06'16.322''
W..
48[deg]09'46.665''
N,
126[deg]25'48.758''
W..
------------------------------------------------------------------------

(2) [Reserved]
(g) Operational Exception for the SURTASS LFA Sonar Sound Field
(1) During military operations SURTASS LFA sonar transmissions may
exceed 180 dB re: 1 [micro]Pa (rms) within the boundaries of a SURTASS
LFA sonar OBIA when: (1) Operationally necessary to continue tracking
an existing underwater contact; or (2) operationally necessary to
detect a new underwater contact within the OBIA. This exception does
not apply to routine training and testing with the SURTASS LFA sonar
systems.
(2) [Reserved]

Sec. 218.235 Requirements for monitoring.

(a) In order to mitigate the taking of marine mammals by SURTASS
LFA sonar to the greatest extent practicable, the Holder of a Letter of
Authorization issued pursuant to Sec. Sec. 216.106 and 218.238 of this
chapter must:
(1) Conduct visual monitoring from the ship's bridge during all
daylight hours (30 minutes before sunrise until 30 minutes after
sunset). During operations that employ SURTASS LFA sonar in the active
mode, the SURTASS vessels shall have lookouts to maintain a topside
watch with standard binoculars (7x) and with the naked eye.
(2) Use low frequency passive SURTASS sonar to listen for
vocalizing marine mammals; and
(3) Use the HF/M3 sonar to locate and track marine mammals in
relation to the SURTASS LFA sonar vessel and the sound field produced
by the SURTASS LFA sonar source array.
(b) Monitoring under paragraph (a) of this section must:
(1) Commence at least 30 minutes before the first SURTASS LFA sonar
transmission;
(2) Continue between transmission pings; and
(3) Continue either for at least 15 minutes after completion of the
SURTASS LFA sonar transmission exercise, or, if marine mammals are
exhibiting unusual changes in behavioral patterns, for a period of time
until behavior patterns return to normal or conditions prevent
continued observations.
(c) Holders of Letters of Authorization for activities described in
Sec. 218.230 are required to cooperate with the National Marine
Fisheries Service and any other federal agency for monitoring the
impacts of the activity on marine mammals.
(d) Holders of Letters of Authorization must designate qualified
on-site individuals to conduct the mitigation, monitoring and reporting
activities specified in the Letter of Authorization.
(e) Holders of Letters of Authorization must conduct all monitoring
required under the Letter of Authorization.

Sec. 218.236 Requirements for reporting.

(a) The Holder of the Letter of Authorization must submit
classified and unclassified quarterly mission reports to the Director,
Office of Protected Resources, NMFS, no later than 30 days after the
end of each quarter beginning on the date of effectiveness of a Letter
of Authorization or as specified in the appropriate Letter of
Authorization. Each quarterly mission report will include all active-
mode missions completed during that quarter. At a minimum, each
classified mission report must contain the following information:
(1) Dates, times, and location of each vessel during each mission;
(2) Information on sonar transmissions during each mission;
(3) Results of the marine mammal monitoring program specified in
the Letter of Authorization; and
(4) Estimates of the percentages of marine mammal species and
stocks affected (both for the quarter and cumulatively for the year)
covered by the Letter of Authorization.
(b) The Holder of a Letter of Authorization must submit an
unclassified annual report to the Director, Office of Protected
Resources, NMFS, no later than 45 days after the expiration of a Letter
of Authorization. The reports must contain all the information required
by the Letter of Authorization.
(c) A final comprehensive report must be submitted to the Director,
Office of Protected Resources, NMFS at least 240 days prior to
expiration of this subpart. In addition to containing all the
information required by any final year Letter of Authorization, this
report must contain an unclassified analysis of new passive sonar
technologies and an assessment of whether such a system is feasible as
an alternative to SURTASS LFA sonar.
(d) The Navy will continue to assess the data collected by its
undersea arrays and work toward making some portion of that data, after
appropriate security reviews, available to scientists with appropriate
clearances. Any portions of the analyses conducted by these scientists
based on these data that are determined to be unclassified after
appropriate security reviews will be made publically available.

Sec. 218.237 Applications for Letters of Authorization.

(a) To incidentally take marine mammals pursuant to this subpart,
the U.S. Navy authority conducting the activity identified in Sec.
218.230 must

[[Page 894]]

apply for and obtain a Letter of Authorization in accordance with Sec.
216.106 of this chapter.
(b) The application for a Letter of Authorization must be submitted
to the Director, Office of Protected Resources, NMFS, at least 60 days
before the date that either the vessel is scheduled to begin conducting
SURTASS LFA sonar operations or the previous Letter of Authorization is
scheduled to expire.
(c) All applications for a Letter of Authorization must include the
following information:
(1) The date(s), duration, and the area(s) where the vessel's
activity will occur;
(2) The species and/or stock(s) of marine mammals likely to be
found within each area;
(3) The type of incidental taking authorization requested (i.e.,
take by Level A and/or Level B harassment);
(4) The estimated percentage of marine mammal species/stocks
potentially affected in each area for the period of effectiveness of
the Letter of Authorization; and
(5) The means of accomplishing the necessary monitoring and
reporting that will result in increased knowledge of the species and
the level of taking or impacts on marine mammal populations.
(d) The National Marine Fisheries Service will review an
application for a Letter of Authorization in accordance with Sec.
216.104(b) of this chapter and, if adequate and complete, issue a
Letter of Authorization.

Sec. 218.238 Letters of Authorization.

(a) A Letter of Authorization, unless suspended or revoked, will be
valid for a period of time not to exceed one year, but may be renewed
annually subject to renewal conditions in Sec. 218.239.
(b) Each Letter of Authorization will set forth:
(1) Permissible methods of incidental taking;
(2) Authorized geographic areas for incidental takings;
(3) Means of effecting the least practicable adverse impact on the
species of marine mammals authorized for taking, their habitat, and the
availability of the species for subsistence uses; and
(4) Requirements for monitoring and reporting incidental takes.
(c) Issuance of a Letter of Authorization will be based on a
determination that the level of taking will be consistent with the
findings made for the total taking allowable under this subpart.
(d) Notice of issuance or denial of an application for a Letter of
Authorization will be published in the Federal Register within 30 days
of a determination.

Sec. 218.239 Renewal of Letters of Authorization.

(a) A Letter of Authorization issued for the activity identified in
Sec. 218.230 may be renewed upon:
(1) Notification to NMFS that the activity described in the
application submitted under Sec. 218.237 will be undertaken and that
there will not be a substantial modification to the described activity,
mitigation or monitoring undertaken during the upcoming season;
(2) Notification to NMFS of the information identified in Sec.
218.237(c);
(3) Timely receipt of the monitoring reports required under Sec.
218.236, which have been reviewed by NMFS and determined to be
acceptable;
(4) A determination by NMFS that the mitigation, monitoring and
reporting measures required under Sec. Sec. 218.234, 218.235, and
218.236 and the previous Letter of Authorization were undertaken and
will be undertaken during the upcoming period of validity of a renewed
Letter of Authorization; and
(5) A determination by NMFS that the level of taking will be
consistent with the findings made for the total taking allowable under
this subpart.
(b) If a request for a renewal of a Letter of Authorization
indicates that a substantial modification to the described work,
mitigation, or monitoring will occur, or if NMFS proposes a substantial
modification to the Letter of Authorization, NMFS will provide a period
of 30 days for public review and comment on the proposed modification.
Amending the areas for upcoming SURTASS LFA sonar operations is not
considered a substantial modification to the Letter of Authorization.
(c) A notice of issuance or denial of a renewal of a Letter of
Authorization will be published in the Federal Register within 30 days
of a determination.

Sec. 218.240 Modifications to Letters of Authorization.

(a) Except as provided in paragraph (b) of this section, no
substantial modification (including withdrawal or suspension) to a
Letter of Authorization subject to the provisions of this subpart shall
be made by NMFS until after notification and an opportunity for public
comment has been provided. For purposes of this paragraph, a renewal of
a Letter of Authorization, without modification, except for the period
of validity and a listing of planned operating areas, or for moving the
authorized SURTASS LFA sonar system from one ship to another, is not
considered a substantial modification.
(b) If NMFS determines that an emergency exists that poses a
significant risk to the well-being of the species or stocks of marine
mammals specified in Sec. 218.230(b)(1), (2), or (3), NMFS may modify
a Letter of Authorization without prior notice and opportunity for
public comment. Notification will be published in the Federal Register
within 30 days of the action.

Sec. 218.241 Adaptive Management.

NMFS may modify or augment the existing mitigation or monitoring
measures (after consulting with the Navy regarding the practicability
of the modifications) if doing so creates a reasonable likelihood of
more effectively accomplishing the goals of mitigation and monitoring
set forth in this subpart. NMFS will provide a period of 30 days for
public review and comment if such modifications are substantial. Below
are some of the possible sources of new data that could contribute to
the decision to modify the mitigation or monitoring measures:
(a) Results from the Navy's monitoring from the previous year's
operation of SURTASS LFA sonar.
(b) Compiled results of Navy-funded research and development
studies.
(c) Results from specific stranding investigations.
(d) Results from general marine mammal and sound research funded by
the Navy or other sponsors.
(e) Any information that reveals marine mammals may have been taken
in a manner, extent or number not anticipated by this subpart or
subsequent Letters of Authorization.

[FR Doc. 2011-33600 Filed 1-5-12; 8:45 am]
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