Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Conducting Air-to-Surface Gunnery Missions in the Gulf of Mexico, 62378-62387 [2011-26018]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 76, Number 195 (Friday, October 7, 2011)]
[Notices]
[Pages 62378-62387]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-26018]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XA471


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Conducting Air-to-Surface Gunnery 
Missions in the Gulf of Mexico

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

ACTION: Notice; issuance of an incidental harassment authorization.

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SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA) 
regulations, notification is hereby given that NMFS has issued an 
Incidental Harassment Authorization (IHA) to the U.S. Air Force (USAF), 
Eglin Air Force Base (Eglin AFB), to take marine mammals, by 
harassment, incidental to conducting air-to-surface (A-S) gunnery 
missions in the Gulf of Mexico (GOM). The USAF's activities are 
considered military readiness activities.

DATES: Effective September 26, 2011, through September 25, 2012.

ADDRESSES: A copy of the authorization, the application containing a 
list of the references used in this document, and NMFS' 2008 
Environmental Assessment (EA) and Finding of No Significant Impact 
(FONSI) may be obtained by writing to Michael Payne, Chief, Permits, 
Conservation and Education Division, Office of Protected Resources, 
National Marine Fisheries Service, 1315 East-West Highway, Silver 
Spring, MD 20910-3225, telephoning the contact listed below (see FOR 
FURTHER INFORMATION CONTACT), or visiting the Internet at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm. Documents cited in this 
notice may also be viewed, by appointment, during regular business 
hours, at the aforementioned address.

FOR FURTHER INFORMATION CONTACT: Brian D. Hopper or Candace Nachman, 
Office of Protected Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization is 
provided to the public for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103 
as ``* * * an impact resulting from the specified activity that cannot 
be reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.''
    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which citizens of the U.S. can apply for an authorization to 
incidentally take small numbers of marine mammals by harassment. 
Section 101(a)(5)(D) establishes a 45-day time limit for NMFS review of 
an application followed by a 30-day public notice and comment period on 
any proposed authorizations for the incidental harassment of marine 
mammals. Within 45 days of the close of the comment period, NMFS must 
either issue or deny the authorization.
    The National Defense Authorization Act (NDAA) (Pub. L. 108-136) 
removed the ``small numbers'' and ``specified geographical region'' 
provisions and amended the definition of ``harassment'' as it applies 
to a ``military readiness activity'' to read as follows (Section 
3(18)(B) of the MMPA):

    (i) Any act that injures or has the significant potential to 
injure a marine mammal or marine mammal stock in the wild [Level A 
Harassment]; or (ii) Any act that disturbs or is likely to disturb a 
marine mammal or marine mammal stock in the wild by causing 
disruption of natural behavioral patterns, including, but not 
limited to, migration, surfacing, nursing, breeding, feeding, or 
sheltering, to a point where such behavioral patterns are abandoned 
or significantly altered [Level B Harassment].

Summary of Request

    NMFS originally received an application on February 13, 2003, from 
Eglin AFB for the taking, by harassment, of marine mammals incidental 
to programmatic mission activities within the Eglin Gulf Test and 
Training Range (EGTTR). The EGTTR is described as the airspace over the 
GOM that is controlled by Eglin AFB. A notice of receipt of Eglin AFB's 
application and Notice of Proposed IHA and request for 30-day public 
comment published on January 23, 2006 (71 FR 3474). A 1-year IHA was 
subsequently issued to Eglin AFB for this activity on May 3, 2006 (71 
FR 27695, May 12, 2006).
    On January 29, 2007, NMFS received a request from Eglin AFB for a 
renewal of its 2006-2007 IHA, which expired on May 2, 2007. This 
application addendum requested revisions to three components of the IHA 
requirements: protected species surveys; ramp-up

[[Page 62379]]

procedures; and sea state restrictions. A Notice of Proposed IHA and 
request for 30-day public comment published on May 30, 2007 (72 FR 
29974). A 1-year IHA was subsequently issued to Eglin AFB for this 
activity on December 11, 2008 (73 FR 78318, December 22, 2008).
    On February 17, 2009, NMFS received a request from Eglin AFB for a 
renewal of its 2008-2009 IHA, which expired on December 10, 2009. No 
modifications to the activity location, the mission activities, or the 
mitigation and monitoring measures required under the 2008-2009 IHA 
were requested by Eglin AFB at that time. A notice of proposed IHA with 
a 30-day public comment period published on October 19, 2009 (74 FR 
53474). A 1-year IHA was subsequently issued to Eglin AFB for this 
activity on January 27, 2010 (75 FR 5045, February 1, 2010), which 
expired on January 26, 2011.
    On May 16, 2011, NMFS received a request from Eglin AFB for a 
renewal of its IHA, which expired on January 26, 2011. The IHA 
application NMFS received on May 16, 2011, is the one considered by 
NMFS for the current request. Eglin AFB has not had coverage for these 
activities since the expiration of the IHA on January 16, 2011; 
however, Eglin AFB has not conducted these activities during the period 
without MMPA coverage and has waited to resume these training missions 
until a new MMPA authorization could be issued by NMFS.
    A-S gunnery operations may potentially impact marine mammals at or 
near the water surface. Marine mammals could potentially be harassed, 
injured, or killed by exploding and non-exploding projectiles, and 
falling debris (USAF, 2002). However, based on analyses provided in the 
USAF's 2002 Final Programmatic EA (PEA), Eglin's Supplemental 
Information Request (2003), and NMFS' 2008 EA, as well as for reasons 
discussed in the Notice of Proposed IHA (76 FR 43267, July 20, 2011) 
and later in this document, NMFS concurs with Eglin AFB that gunnery 
exercises are not likely to result in any injury or mortality to marine 
mammals. Potential impacts resulting from A-S test operations include 
direct physical impacts (DPI) resulting from ordnance. Six marine 
mammal species or stocks are authorized for taking by Level B 
harassment incidental to Eglin AFB's A-S activities and include: dwarf 
sperm whale (Kogia simus); pygmy sperm whale (K. breviceps); Atlantic 
bottlenose dolphin (Tursiops truncatus); Atlantic spotted dolphin 
(Stenella frontalis); pantropical spotted dolphin (S. attenuata); and 
spinner dolphin (S. longirostris).

Description of the Specified Activity

    A-S gunnery missions, a ``military readiness activity'' as defined 
under 16 U.S.C. 703 note, involve surface impacts of projectiles and 
small underwater detonations with the potential to affect cetaceans 
that may occur within the EGTTR. These missions typically involve the 
use of 25-mm (0.98-in), 40-mm (1.57-in), and 105-mm (4.13-in) gunnery 
rounds containing, 0.0662 lb (30 g), 0.865 lb (392 g), and 4.7 lbs (2.1 
kg) of explosive, respectively. Live rounds must be used to produce a 
visible surface splash that must be used to ``score'' the round (the 
impact of inert rounds on the sea surface would not be detected). The 
USAF has developed a 105-mm training round (TR) that contains less than 
10 percent of the amount of explosive material (0.35 lb; 0.16 kg) as 
compared to the ``Full-Up'' (FU) 105-mm (4.13 in) round. The TR was 
developed as one method to mitigate effects on marine life during 
nighttime A-S gunnery exercises when visibility at the water surface is 
poor. However, the TR cannot be used in the daytime since the amount of 
explosive material is insufficient to be detected from the aircraft.
    Water ranges within the EGTTR that are typically used for the 
gunnery operations are located in the GOM offshore from the Florida 
Panhandle (areas W-151A, W-151B, W-151C, and W-151D as shown in Figure 
1-2 in Eglin's 2011 application). Data indicate that W-151A (Figure 1-3 
in Eglin's application) is the most frequently used water range due to 
its proximity to Hurlburt Field, but activities may occur anywhere 
within the EGTTR.
    Eglin AFB proposes to conduct these mission activities year round 
during both daytime and nighttime hours. Therefore, NMFS has made the 
IHA effective for an entire year from September 26, 2011, through 
September 25, 2012. However, it should be noted that the level of 
activity has been far lower over the past few years than that predicted 
to be conducted by the USAF and by NMFS in this document for two 
reasons. First, many of the training crew members have been engaged in 
other activities in other parts of the world recently. Second, land 
ranges are the preferred method of live-fire training. Under the 
previous IHA, the USAF crews did not use the water ranges due to the 
excellent availability of land ranges. However, if at some point in the 
future land ranges may become more difficult to acquire, water ranges 
are needed to ensure that aircrews can be fully trained. A detailed 
overview of the activity was provided in the Notice of Proposed IHA (76 
FR 43267, July 20, 2011). No changes have been made to the proposed 
activities.

Comments and Responses

    A notice of receipt of Eglin AFB's application and NMFS' proposal 
to issue an IHA to the USAF, Eglin AFB, published in the Federal 
Register on July 20, 2011 (76 FR 43267). During the 30-day public 
comment period, NMFS only received comments from the Marine Mammal 
Commission (MMC). Following are the comments from the MMC and NMFS' 
responses.
    Comment 1: The MMC recommends that NMFS withhold issuing the IHA 
until the Air Force has provided a clear, step-by-step description of 
how it estimated the zones of exposure and associated number of takes 
for the sound exposure level thresholds, accounting for the multiple 
types and quantities of rounds to be used for representative missions.
    Response: NMFS does not agree with the MMC that the IHA should not 
be issued until additional information regarding the zones of exposure 
and number of takes can be provided. The methodology and analytical 
approach for determining the exposure zones and estimating the number 
of marine mammal takes was fully explained in the 2011 IHA application, 
2011 IHA Notice of Proposed IHA (76 FR 43267, July 20, 2011), as well 
as in the previous IHAs and supporting documents issued for this 
activity. Readers should refer to those documents for additional 
information, but a summary follows.
    Three sources of information are necessary for estimating the 
potential impacts of in-water noise from explosive detonations on 
marine mammals: (1) The zone of influence, defined as the distance from 
the explosion to which a particular energy (dB) or pressure (psi) 
threshold extends; (2) the density of animals potentially occurring 
within the zone of influence; and (3) the number of distinct firing 
events. Table 6-1 in the 2011 IHA application provides the criteria and 
thresholds used for assessing potential noise impacts to marine mammals 
and Table 6-2 provides the estimated range from the detonation point to 
which the various thresholds extend. Threshold ranges were calculated 
for two seasons (summer and winter) and depth strata (80 m and 160 m) 
in order to reasonably bound the environmental conditions under which 
A-S gunnery activities may occur. As a conservative measure, the 
greatest range within each season and depth strata were used to 
estimate marine mammal takes. In addition, where dual criteria exist 
(e.g., pressure

[[Page 62380]]

and energy thresholds for explosives), the criterion that resulted in 
the most conservative estimate (i.e., largest amount of take) was used. 
Appendix A of the 2011 IHA application provides a more detailed 
explanation on how the ranges were calculated for the criteria and 
thresholds used in this analysis.
    As discussed in section 3 of the 2011 IHA application and in the 
2011 IHA Notice of Proposed IHA (76 FR 43267, July 20, 2011), marine 
mammal densities were derived from the Navy OPAREA Density Estimates 
(NODE) for the GOMEX OPAREA report, and were determined by either 
model-derived estimates or literature-derived estimates. In order to 
address potential negative bias in the underlying survey results, Eglin 
AFB adjusted density estimates using marine mammal submergence factors. 
The density estimates for marine mammals occurring in the EGTTR are 
provided in Table 3.
    The final source of information required to conduct the analysis is 
the number of distinct firing events from A-S gunnery missions. The 
method of deriving the number of firing events may differ for energy 
and pressure metrics applied to explosive detonations. For energy 
metrics, the number of firing events is synonymous with the quantity of 
rounds expended because energy is proportional to the total charge 
weight. When utilizing energy threshold metrics, the energy released 
from multiple shots is evaluated as an additive exposure and, 
therefore, firing events must consider all shots fired. Conversely, it 
is not necessarily appropriate to consider pressure as additive when 
multiple explosions occur simultaneously or over a very short time 
frame, and an alternative method for estimating the number of events 
for use in take calculations is applied. Typically, pressure-based 
thresholds are based on the maximum level received by an animal in 
pounds per square inch (psi).
    The method for estimating the number of firing events for 40 mm and 
25 mm rounds, with respect to the pressure metric, is based on firing 
protocols. For example, these rounds are generally fired in bursts, 
with each burst lasting from 2 to 10 seconds. When the average cetacean 
density and swim speed of approximately 3 knots (1.5 m/sec) are taken 
into consideration, there is not enough time for new animals to enter 
the zone of influence within the time frame of a single burst. 
Therefore, marine mammals are only exposed to the peak pressure of a 
single round per burst within a particular zone of influence. For 40 mm 
rounds, a typical mission includes 64 rounds and approximately 20 
rounds per burst. Based on the size of the target area and small 
``miss'' distance, all rounds in a burst are expected to enter the 
water within 5 meters of the target. Therefore, pressure-related take 
calculations are based on the total number of rounds fired per year 
divided by 20. Similarly, for 25 mm rounds, missions typically entail 
560 rounds fired in bursts of 100 rounds, and take calculations are 
based on the number of rounds divided by 100.
    The firing protocol for 105 mm rounds does not include bursts 
because these rounds are fired in single shots with up to 30-second 
intervals between rounds, which results in approximately two rounds per 
minute. Therefore, an adjustment for burst quantity is not applicable 
and pressure-related exposure calculations are performed using all 
rounds expended.
    Using this approach, Eglin AFB estimated the number of marine 
mammal takes using the adjusted density estimates for each species, the 
zone of influence of each type of round deployed, and the total number 
of events per year. The results are presented in Table 3.
    Comment 2: The MMC recommends that NMFS require performance testing 
of mitigation measures to assess their actual effectiveness at 
detecting marine mammals and minimizing takes. The Navy is being asked 
to conduct similar evaluation programs, and doing so seems essential if 
our collective approach to such matters is to be considered science-
based.
    Response: Since the MMC did not make any specific recommendations 
regarding the performance testing of mitigation measures to assess 
their actual effectiveness at detecting marine mammals, NMFS is 
uncertain as to what exactly it is the MMC is recommending be done in 
this instance. Regarding the evaluation programs being conducted by the 
Navy, NMFS assumes that the MMC is referring to the effectiveness of 
visual observations by vessel-based marine mammal observers based on 
years of experience. The Navy's evaluation monitoring is in no way 
comparable to the activities being conducted here by Eglin AFB.
    An addendum to the IHA application submitted by Eglin AFB in 
January 2007 explained in detail the advantages and improved 
effectiveness of using the Infrared Detection Sets (IDS) system over 
typical night-vision devices and other visual observation systems. The 
IDS system is capable of detecting differences in temperature from 
thermal energy (heat) radiated from living bodies or from reflected and 
scattered thermal energy. Visible light is not necessary for object 
detection. This system is equally effective during day or night use. 
For a full explanation on the IDS system and its effectiveness, please 
refer to the 2008 IHA Notice of Issuance (73 FR 78318, December 22, 
2008), Eglin AFB's 2007 application addendum, or NMFS' 2008 EA (see 
ADDRESSES). These documents also describe the effectiveness of this 
system at 6,000 ft (1,829 m) altitude, which was a requested change by 
the USAF due to safety concerns for personnel if protected species 
surveys were flown at lower altitudes.
    Aircraft crew members are required to scan the testing area prior 
to the commencement of all A-S gunnery mission activities, for which 
optical and electronic sensors are required to be employed for target 
detection. If any marine mammals are detected within the AC-130's orbit 
circle, either during initial clearance or after commencement of live 
firing, the mission will be immediately halted and relocated as 
necessary or suspended until the marine mammal has left the area. If 
relocated to another target area, the clearance procedures must be 
repeated. Based on the analysis of effectiveness of the observation 
systems, NMFS has determined that flying the pre-mission surveys at an 
altitude of 6,000 ft (1,829 m) is a sufficient altitude to detect the 
presence of marine mammals. Since gunnery mission activities will not 
occur prior to the completion of these surveys, it is safe to assume 
that any sighted marine mammals reported dead would have died from a 
cause other than Eglin AFB's A-S activities.
    Regarding the effectiveness of differentiating between a live and a 
dead marine mammal during post-mission protected species surveys, 
unless there is significant physical damage, the operators/systems are 
not capable of determining between a non-moving live animal and a dead 
animal with no apparent physical damage. Typically, marine mammals do 
not exhibit the same levels of energy/heat transfer back into the 
environment that is associated with land animals due to their 
insulating fat layers. However, the USAF has stated that they would be 
able to see a wounded or recently killed marine mammal on or near the 
surface that is bleeding externally or with significant open wounds, as 
this would provide a heat signature that can be detected quite well by 
the IDS system.
    Additionally, the size of the wound, time elapsed since the injury 
was incurred, and orientation of the animal/wound are all factors 
determining whether or not one could see the gunnery-type wounds (such 
as bullet

[[Page 62381]]

holes or fragmentation wounds). However, the weapons used during A-S 
exercises detonate on or very near the surface. According to the USAF, 
even if the weapon failed to detonate, gun-type projectiles lose lethal 
velocity within a few feet of the surface. Lastly, if a marine mammal 
enters the exercise area during a live-fire event, exercises would 
cease immediately, and the activity would either remain suspended until 
the area was determined to be clear of marine mammals or moved to a new 
area, where pre-mission surveys would be conducted before recommencing 
live-fire events.
    Comment 3: The MMC states that until data are available that 
demonstrate the effectiveness of electronic detection techniques in 
higher sea states, authorizing incidental taking during operations 
conducted in such conditions is premature. Therefore, the MMC 
recommends that NMFS work with the USAF to design and conduct the 
necessary performance verification testing for electronic detection 
devices under the pertinent sea state conditions.
    Response: For the 2008 IHA, NMFS increased the sea state 
restriction from 3 to 4. The reasoning for increasing the sea state 
limitation was fully explained in the 2008 IHA Notice of Issuance (73 
FR 78318, December 22, 2008) and NMFS' 2008 EA. Readers should refer to 
those documents for the explanation.
    USAF subject matter experts have determined based on in-the-field 
experience, the airborne systems adequately function in a sea state of 
4. Research conducted by Baldacci et al. (2005) indicated a sea state 
of 2 or 3 was pushing their system capabilities. However, Baldacci et 
al. (2005) were looking horizontally along the surface of the water, 
whereas the USAF is looking nearly straight down, thus improving system 
capabilities in higher sea states. Specific system capabilities/
limitations are classified and cannot be publicly provided.
    Sensor Operators are continuously scanning the area for traffic, 
boats, marine mammals, etc. when transiting to and from the water 
exercise ranges. The USAF will instruct the Sensor Operators to begin 
gathering additional data, such as sea state and level of difficulty in 
detecting objects at the different sea states, during those transits 
for comparison purposes, as long as doing so does not interfere with 
mission training activities. Beyond this new data collection effort, 
NMFS is uncertain what the MMC intended, as they did not provide any 
specific details on the types of data that should be collected or 
collection methods.

Description of Marine Mammals in the Area of the Specified Activity

    There are 29 species of marine mammals documented as occurring in 
Federal waters of the GOM. Of these 29 species of marine mammals, 
approximately 21 may be found within the proposed action area, the 
EGTTR. These species are the Bryde's whale, sperm whale, dwarf sperm 
whale, pygmy sperm whale, Atlantic bottlenose dolphin, Atlantic spotted 
dolphin, pantropical spotted dolphin, Blainville's beaked whale 
(Mesoplodon densirostris), Cuvier's beaked whale, Gervais' beaked whale 
(M. europaeus), Clymene dolphin, spinner dolphin, striped dolphin, 
killer whale (Orcinus orca), false killer whale, pygmy killer whale, 
Risso's dolphin, Fraser's dolphin (Lagenodelphis hosei), melon-headed 
whale (Peponocephala electra), rough-toothed dolphin, and short-finned 
pilot whale. Of these species, only the sperm whale is listed as 
endangered under the Endangered Species Act (ESA) and as depleted 
throughout its range under the MMPA. While some of the other species 
listed here have depleted status under the MMPA, none of the GOM stocks 
of those species are considered depleted. More detailed information on 
these species can be found in Wursig et al. (2000), NMFS' 2008 EA (see 
ADDRESSES), and in the NMFS U.S. Atlantic and GOM Stock Assessment 
Reports (Waring et al., 2009). This latter document is available at: 
https://www.nefsc.noaa.gov/publications/tm/tm210/. The West Indian 
manatee (Trichechus manatus) is managed by the U.S. Fish and Wildlife 
Service and is not considered further in this document.
    The species most likely to occur in the area of Eglin AFB's 
proposed activities for which takes have been requested include: 
Atlantic bottlenose dolphin; Atlantic spotted dolphin; pantropical 
spotted dolphin; spinner dolphin; and dwarf and pygmy sperm whales. 
Bryde's whales, sperm whales, Risso's dolphins, Clymene dolphins, 
striped dolphins, Blainville's beaked whales, Cuvier's beaked whales, 
Gervais' beaked whales, killer whales, false killer whales, pygmy 
killer whales, Fraser's dolphins, rough-toothed dolphins, short-finned 
pilot whales, and melon-headed whales are rare in the project area and 
are not anticipated to be impacted by the A-S gunnery mission 
activities. Therefore, these species are not considered further.
    For cetacean species other than the bottlenose dolphin, density 
estimates were derived from the Navy OPAREA Density Estimates (NODE) 
for the GOMEX OPAREA report (DON, 2007). Bottlenose dolphin density 
estimates were derived from Protected Species Habitat Modeling in the 
EGTTR (Garrison, 2008). A complete discussion on the abundance and 
density data can be found in the Notice of Proposed IHA (76 FR 43267, 
July 20, 2011) and Eglin AFB's IHA application.

Potential Effects of the Specified Activity on Marine Mammals

    A-S gunnery operations may potentially impact marine mammals at or 
near the water surface. Marine mammals could potentially be harassed, 
injured or killed by exploding and non-exploding projectiles, and 
falling debris (USAF, 2002). However, based on analyses provided in the 
USAF's Final PEA, Eglin's Supplemental Information Request (2003), and 
NMFS' 2008 EA, NMFS concurs with Eglin AFB that A-S gunnery exercises 
are not likely to result in any injury or mortality to marine mammals.
    Explosive criteria and thresholds for assessing impacts of 
explosions on marine mammals were discussed by NMFS in detail in its 
issuance of an IHA for Eglin's Precision Strike Weapon testing activity 
(70 FR 48675, August 19, 2005) and are not repeated here. Please refer 
to that document for this background information. However, one part of 
the analysis has changed since that time. That information was provided 
in the Notice of Proposed IHA (76 FR 43267, July 20, 2011) and is not 
repeated here. Table 1 in this document outlines the acoustic criteria 
used by NMFS when addressing noise impacts from explosives. These 
criteria remain consistent with criteria established for other 
activities in the EGTTR and other acoustic activities authorized under 
sections 101(a)(5)(A) and (D) of the MMPA.

 Table 1--Current NMFS Acoustic Criteria When Addressing Harassment From
                               Explosives
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Level B Behavior.......................  177 dB re 1 [micro]Pa\2\-sec \1/
                                          3\ Octave SEL (sound energy
                                          level).
Level B TTS Dual Criterion.............  182 dB re 1 [micro]Pa\2\-sec \1/
                                          3\ Octave SEL.
Level B TTS Dual Criterion.............  23 psi.
Level A PTS (permanent threshold shift)  205 dB re 1 [micro]Pa\2\-sec
                                          SEL.

[[Page 62382]]

 
Level A Injury (non-hearing related)...  13 psi-msec.
Mortality..............................  30.5 psi-msec.
------------------------------------------------------------------------

    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. 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 it 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 permanent threshold shift (PTS), they are within the 
normal bounds of physiological variability and tolerance and do not 
represent a physical injury. Additionally, Southall et al. (2007) 
indicate that although PTS is a tissue injury, TTS is not, because the 
reduced hearing sensitivity following exposure to intense sound results 
primarily from fatigue, not loss, of cochlear hair cells and supporting 
structures and is reversible. Accordingly, NMFS classifies TTS (when 
resulting from exposure to underwater detonations) as Level B 
Harassment, not Level A Harassment (injury).

Direct Physical Impacts (DPI)

    Potential impacts resulting from A-S test operations include DPI 
resulting from ordnance. DPI could result from inert bombs, gunnery 
ammunition, and shrapnel from live missiles falling into the water. 
However, the possibility of DPI to marine mammals is considered highly 
unlikely. Therefore, the risk of injury or mortality is low. The Notice 
of Proposed IHA (76 FR 43267, July 20, 2011) contained a complete 
discussion of possible impacts from DPI on marine mammals. Impacts to 
marine mammals from Eglin AFB's activities are anticipated to be 
limited to Level B harassment in the form of temporary changes in 
behavior or temporary changes in hearing thresholds (i.e., TTS).

Anticipated Effects on Marine Mammal Habitat

    The primary source of marine mammal habitat impact is noise 
resulting from gunnery missions. However, the noise does not constitute 
a long-term physical alteration of the water column or bottom 
topography, as the occurrences are of limited duration and are 
intermittent in time. Other sources that may affect marine mammal 
habitat were considered and potentially include the introduction of 
fuel, chaff, debris, ordnance, and chemical residues into the water 
column. A full description of anticipated effects on habitat was 
provided in the Notice of Proposed IHA (76 FR 43267, July 20, 2011). 
Based on that information, NMFS has determined that the A-S gunnery 
mission activities will not have any impact on the food or feeding 
success of marine mammals in the northern GOM. Additionally, no loss or 
modification of the habitat used by cetaceans in the GOM is expected. 
The activity is not expected to have any habitat-related effects that 
could cause significant or long-term consequences for individual marine 
mammals or on the food sources that they utilize.

Mitigation

    In order to issue an incidental take authorization (ITA) under 
Section 101(a)(5)(A) and (D) of the MMPA, NMFS must, where applicable, 
set forth the permissible methods of taking pursuant to such activity 
and other means of effecting the least practicable impact on such 
species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking for certain 
subsistence uses (where relevant). The NDAA of 2004 amended the MMPA as 
it relates to military readiness activities and the ITA process such 
that ``least practicable 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 Eglin AFB's application are considered military 
readiness activities.
    The mitigation measures included in this IHA are the same as those 
required in the 2010-2011 IHA (75 FR 5045, February 1, 2010). These 
measures are virtually identical to the mitigation measures that were 
required in the 2008-2009 IHA (73 FR 78318, December 22, 2008) and the 
2006 IHA (71 FR 27695, May 12, 2006). There were only three differences 
in the mitigation and monitoring measures between the 2006 and 2008 
IHAs. Eglin AFB's 2007 application addendum requested revisions to 
three components of the IHA requirements: Protected species surveys, 
ramp-up procedures, and sea state restrictions. A discussion of the 
differences in the requirements can be found in the 2008 IHA Notice of 
Issuance (73 FR 78318, December 22, 2008) and NMFS' 2008 EA (see 
ADDRESSES). The revisions to those three requirements are also included 
in this IHA. However, the explanations as to why Eglin AFB requested 
the changes and NMFS' determinations specific to those three 
requirements are not repeated in this document. Readers should refer to 
either the 2008 IHA Notice of Issuance (73 FR 78318, December 22, 2008) 
or NMFS' 2008 EA (see ADDRESSES) for the full explanation.

Development of the Training Round (TR)

    The largest type of ammunition used during typical gunnery missions 
is the 105-mm (4.13-in) round containing 4.7 lbs (2.1 kg) of high 
explosive (HE). This is several times more HE than that found in the 
next largest round (40 mm/1.57 in). As a mitigation technique, the USAF 
developed a 105-mm TR that contains only 0.35 lb (0.16 kg) of HE. The 
TR was developed to dramatically reduce the risk of harassment at night 
and Eglin AFB anticipates a 96 percent reduction in impact by using the 
105-mm TR.

[[Page 62383]]

Visual Mitigation

    Areas to be used in gunnery missions are visually monitored for 
marine mammal presence from the AC-130 aircraft prior to commencement 
of the mission. If the presence of one or more marine mammals is 
detected, the target area will be avoided. In addition, monitoring will 
continue during the mission. If marine mammals are detected at any 
time, the mission will halt immediately and relocate as necessary or be 
suspended until the marine mammal has left the area. Daytime and 
nighttime visual monitoring will be supplemented with infrared (IR) and 
low-light television (TV) monitoring. As nighttime visual monitoring is 
generally considered to be ineffective at any height, the EGTTR 
missions will incorporate the TR.

Ramp-Up Procedures

    The rationale for requiring ramp-up procedures is that this process 
may allow animals to perceive steadily increasing noise levels and to 
react, if necessary, before the noise reaches a threshold of 
significance. The AC-130 gunship's weapons are used in two activity 
phases. First, the guns are checked for functionality and calibrated. 
This step requires an abbreviated period of live fire. After the guns 
are determined to be ready for use, the mission proceeds under various 
test and training scenarios. This second phase involves a more extended 
period of live fire and can incorporate use of one or any combination 
of the munitions available (25-, 40-, and 105-mm rounds). The ramp-up 
procedure is required for the initial gun calibration, and, after this 
phase, the guns may be fired in any order. Eglin and NMFS believe this 
process will allow marine species the opportunity to respond to 
increasing noise levels. If an animal leaves the area during ramp-up, 
it is unlikely to return while the live-fire mission is proceeding. 
This protocol allows a more realistic training experience. In combat 
situations, gunship crews would not likely fire the complete ammunition 
load of a given caliber gun before proceeding to another gun. Rather, a 
combination of guns would likely be used as required by an evolving 
situation. An additional benefit of this protocol is that mechanical or 
ammunition problems on an individual gun can be resolved while live 
fire continues with functioning weapons. This also diminishes the 
possibility of a lengthy pause in live fire, which, if greater than 10 
min, would necessitate Eglin's re-initiation of protected species 
surveys (described next).

Other Mitigation

    In addition to the development of the TR, the visual mitigation, 
and the ramp-up procedures already described in this document, 
additional mitigation measures to protect marine life were included in 
the 2006, 2008, 2009, and 2010 IHAs and are also required in the 2011 
IHA. These requirements are:
    (1) If daytime weather and/or sea conditions preclude adequate 
aerial surveillance for detecting marine mammals and other marine life, 
A-S gunnery exercises must be delayed until adequate sea conditions 
exist for aerial surveillance to be undertaken. Daytime test firing 
will be conducted only when sea surface conditions are sea state 4 or 
less on the Beaufort scale.
    (2) Prior to each firing event, the aircraft crew will conduct a 
visual survey of the 5-nm (9.3-km) wide prospective target area to 
attempt to sight any marine mammals that may be present (the crew will 
do the same for sea turtles and Sargassum rafts). The AC-130 gunship 
will conduct at least two complete orbits at a minimum safe airspeed 
around a prospective target area at a maximum altitude of 6,000 ft 
(1,829 m). Provided marine mammals (and other protected species) are 
not detected, the AC-130 can then continue orbiting the selected target 
point as it climbs to the mission testing altitude. During the low 
altitude orbits and the climb to testing altitude, the aircraft crew 
will visually scan the sea surface within the aircraft's orbit circle 
for the presence of marine mammals. Primary emphasis for the surface 
scan will be upon the flight crew in the cockpit and personnel 
stationed in the tail observer bubble and starboard viewing window. The 
AC-130's optical and electronic sensors will also be employed for 
target clearance. If any marine mammals are detected within the AC-
130's orbit circle, either during initial clearance or after 
commencement of live firing, the aircraft will relocate to another 
target and repeat the clearance procedures. If multiple firing events 
occur within the same flight, these clearance procedures will precede 
each event.
    (3) The aircrews of the A-S gunnery missions will initiate location 
and surveillance of a suitable firing site immediately after exiting 
U.S. territorial waters (less than or equal to 12 nm (22 km)). This 
would potentially restrict most gunnery activities to the shallower 
continental shelf waters of the GOM where marine mammal densities are 
typically lower, and thus potentially avoid the slope waters where the 
more sensitive species (e.g., endangered sperm whales) typically 
reside.
    (4) Observations will be accomplished using all-light TV, IR 
sensors, and visual means for at least 60 min prior to each exercise.
    (5) Aircrews will utilize visual, night vision goggles, and other 
onboard sensors to search for marine mammals while performing area 
clearance procedures during nighttime pre-mission activities.
    (6) If any marine mammals are sighted during pre-mission surveys or 
during the mission, activities will be immediately halted until the 
area is clear of all marine mammals for 60 min or the mission location 
relocated and resurveyed.
    (7) If post-detonation surveys determine that an injury or lethal 
take of a marine mammal has occurred, the test procedure and the 
monitoring methods must be reviewed with NMFS and appropriate changes 
must be made, prior to conducting the next A-S gunnery exercise.
    NMFS carefully evaluated the applicant's proposed mitigation 
measures and considered a range of other measures in the context of 
ensuring that NMFS prescribes the means of effecting the least 
practicable 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, 
practicability of implementation, and impact on the effectiveness of 
the military-readiness activity.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, NMFS has determined that the 
required mitigation measures provide the means of effecting the least 
practicable impact on marine mammal species or stocks and their 
habitat, paying particular attention to rookeries, mating grounds, and 
areas of similar significance, while also considering personnel safety, 
practicability of implementation, and impact on the effectiveness of 
the military-readiness activity.

Monitoring and Reporting

    In order to issue an ITA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must, where

[[Page 62384]]

applicable, set forth ``requirements pertaining to the monitoring and 
reporting of such taking''. The MMPA implementing regulations at 50 CFR 
216.104 (a)(13) indicate that requests for ITAs must include the 
suggested means of accomplishing the necessary monitoring and reporting 
that will result in increased knowledge of the species and of the level 
of taking or impacts on populations of marine mammals that are expected 
to be present in the action area.
    The Incidental Take Statement in NMFS' Biological Opinion on this 
action required certain monitoring measures to protect marine life. 
NMFS also imposed these same requirements, as well as additional ones, 
under Eglin AFB's 2006, 2008, and 2010 IHAs as they related to marine 
mammals. NMFS has included these same measures in the 2011 IHA. They 
are:
    (1) The A-S gunnery mission aircrews will participate in the marine 
mammal species observation training. Designated crew members will be 
selected to receive training as protected species observers. Observers 
will receive training in protected species survey and identification 
techniques.
    (2) Aircrews will initiate the post-mission clearance procedures 
beginning at the operational altitude of approximately 15,000 to 20,000 
ft (4,572 to 6,096 m) elevation, and then initiate a spiraling descent 
down to an observation altitude of approximately 6,000 ft (1,829 m) 
elevation. Rates of descent will occur over a 3 to 5 min time frame.
    (3) Eglin will track their use of the EGTTR for test firing 
missions and protected species observations, through the use of mission 
reporting forms.
    (4) A-S gunnery missions will coordinate with next-day flight 
activities to provide supplemental post-mission observations for marine 
mammals in the operations area of the previous day.
    (5) A summary annual report of marine mammal observations and A-S 
activities will be submitted to the NMFS Southeast Regional Office 
(SERO) and the Office of Protected Resources either at the time of a 
request for renewal of an IHA or 90 days after expiration of the 
current IHA if a new IHA is not requested. This annual report must 
include the following information: (i) Date and time of each A-S 
gunnery exercise; (ii) a complete description of the pre-exercise and 
post-exercise activities related to mitigating and monitoring the 
effects of A-S gunnery exercises on marine mammal populations; (iii) 
results of the monitoring program, including numbers by species/stock 
of any marine mammals noted injured or killed as a result of the 
gunnery exercises and number of marine mammals (by species if possible) 
that may have been harassed due to presence within the 5-nm activity 
zone; and (iv) a detailed assessment of the effectiveness of sensor-
based monitoring in detecting marine mammals in the area of A-S gunnery 
operations.
    (6) If any dead or injured marine mammals are observed or detected 
prior to testing, or injured or killed during live fire, a report must 
be made to NMFS by the following business day.
    (7) Any unauthorized takes of marine mammals (i.e., injury or 
mortality) must be immediately reported to NMFS and to the respective 
stranding network representative.
    Estimated Take by Incidental Harassment
    As it applies to a ``military readiness activity'', the definition 
of harassment is (Section 3(18)(B) of the MMPA):

    (i) Any act that injures or has the significant potential to 
injure a marine mammal or marine mammal stock in the wild [Level A 
Harassment]; or (ii) Any act that disturbs or is likely to disturb a 
marine mammal or marine mammal stock in the wild by causing 
disruption of natural behavioral patterns, including, but not 
limited to, migration, surfacing, nursing, breeding, feeding, or 
sheltering, to a point where such behavioral patterns are abandoned 
or significantly altered [Level B Harassment].

    Only take by Level B harassment is anticipated as a result of and 
authorized for the A-S gunnery mission activities. The exercises are 
expected to only affect animals at or very near the surface of the 
water. Cetaceans in the vicinity of the exercises may incur temporary 
changes in behavior and/or temporary changes in their hearing 
thresholds. Based on the mitigation and monitoring measures required to 
be implemented (described earlier in this document), no injury or 
mortality of marine mammals is anticipated as a result of or authorized 
for the A-S gunnery mission activities.
    The Notice of Proposed IHA (76 FR 43267, July 20, 2011) included an 
in-depth discussion of the methodology used by Eglin AFB and NMFS to 
estimate take by harassment incidental to the A-S gunnery exercises and 
the numbers of cetaceans that might be affected by the exercises. A 
summary is provided here.
    DPI are only anticipated to affect marine species at or very near 
the ocean surface. As a result, in order to calculate impacts, Eglin 
used corrected species densities (see Table 4-23 in the USAF's Final 
PEA) to reflect the surface interval population, which is approximately 
10 percent of densities calculated for distribution in the total water 
column. The impacts to marine mammals swimming at the surface that 
could potentially be injured or killed by projectiles and falling 
debris was determined to be an average of 0.2059 marine mammals per 
year. However, NMFS believes that the required mitigation measures 
would significantly reduce even these low levels.
    In addition to small arms, Eglin calculated the potential for other 
non-explosive items (bombs, missiles, and drones) to impact marine 
mammals. As shown in the 2002 Final PEA and the Notice of Proposed IHA 
(74 FR 53474, October 19, 2009), the potential for any non-small arms/
non-gunnery DPI to marine mammals is extremely remote and can, 
therefore, be discounted.
    Similar to non-small arms/non-gunnery DPI, DPI from gunnery 
activities may also affect marine mammals in the surface zone. Again, 
DPI are anticipated to affect only marine mammals at or near the ocean 
surface. Accordingly, the density estimates have been adjusted to 
indicate surface animals only being potentially affected. DPI from 
gunnery activities are extremely remote and can be discounted. Using 
the largest round (105 mm), it would take approximately 120 years to 
impact a marine mammal from daytime gunnery activities and 
approximately 27 years to impact a marine mammal from nighttime gunnery 
activities.
    Estimating the impacts to marine mammals from underwater 
detonations is difficult due to complexities of the physics of 
explosive sound under water and the limited understanding with respect 
to hearing in marine mammals. Detailed assessments were made in the 
notice for the 2006 and 2008 IHAs on this action (71 FR 27695, May 12, 
2006; 73 FR 78318, December 22, 2008), as well as the Notice of 
Proposed IHA (74 FR 53474, October 19, 2009) and are summarized in this 
document. These assessments used, and improved upon, the criteria and 
thresholds for marine mammal impacts that were developed for the shock 
trials of the USS SEAWOLF and the USS WINSTON S. CHURCHILL (DDG-81) 
(Navy, 1998; 2001). The criteria and thresholds used in those actions 
were adopted by NMFS for use in calculating incidental takes from 
explosives. Criteria for assessing impacts from Eglin AFB's A-S gunnery 
exercises include: (1) Mortality, as determined by exposure to a 
certain level of positive impulse pressure (expressed as pounds per 
square inch per millisecond or psi-msec); (2) injury, both hearing-
related and non-hearing

[[Page 62385]]

related; and (3) harassment, as determined by a temporary loss of some 
hearing ability and behavioral reactions.
    Permanent hearing loss is considered an injury and is termed PTS. 
NMFS, therefore, categorizes PTS as Level A harassment. Temporary loss 
of hearing ability is termed TTS, meaning a temporary reduction of 
hearing sensitivity which abates following noise exposure. TTS is 
considered non-injurious and is categorized as Level B harassment. NMFS 
recognizes dual criteria for TTS, as well as for Level A harassment, 
one based on peak pressure and one based on the greatest \1/3\ octave 
sound exposure level (SEL) or energy flux density level (EFDL), with 
the more conservative (i.e., larger) of the two criteria being selected 
for impacts analysis (note: SEL and EFDL are used interchangeably, but 
with increasing scientific preference for SEL). The peak pressure 
metric used in previous shock trials to represent TTS was 12 pounds per 
square inch (psi) which, for the net explosive weight used, resulted in 
a zone of possible Level B harassment approximately equal to that 
obtained by using a 182 decibel (dB) re 1 microPa\2\-s, total EFDL/SEL 
metric. The 12-psi metric is largely based on anatomical studies and 
extrapolations from terrestrial mammal data (see Ketten, 1995; Navy, 
1999 (Appendix E, CHURCHILL FEIS; and 70 FR 48675 (August 19, 2005)) 
for background information). However, the results of a more recent 
investigation involving marine mammals suggest that, for small charges, 
the 12-psi metric is not an adequate predictor of the onset of TTS but 
that one should use 23 psi. This explanation was provided in the Notice 
of Proposed IHA (76 FR 43267, July 20, 2011).
    Table 1 (earlier in this document) summarizes the relevant 
thresholds for levels of noise that may result in Level A harassment 
(injury) or Level B harassment via TTS or behavioral disturbance to 
marine mammals. Mortality and injury thresholds are designed to be 
conservative by considering the impacts that would occur to the most 
sensitive life stage (e.g., a dolphin calf). Table 2 provides the 
estimated ZOI radii for the EGTTR ordnance.

               Table 2--Estimated Range for a Zone of Impact (ZOI) Distance for the EGTTR Ordnance
----------------------------------------------------------------------------------------------------------------
                                                                 Level B                             Level B
                                      Level A harassment--   harassment non-       Level B      harassment--non-
             Expendable                injurious (205 dB)    injurious (182    harassment non-   injurious (177
                                            EFD (m)          dB) EFD for TTS    injurious (23      dB) EFD for
                                                                   (m)        psi) for TTS (m)    behavior (m)
----------------------------------------------------------------------------------------------------------------
105-mm FU..........................                 0.79                11.1               216              22.1
105-mm TR..........................                 0.22                 3.0                90               6.0
40-mm HE...........................                 0.33                 4.7               122               9.4
25-mm HE...........................                 0.11                 1.3                49               2.6
----------------------------------------------------------------------------------------------------------------
FU = Full-up; TR = Training Round; HE = High Explosive.

    Based on the detailed discussion contained in the Notice of 
Proposed IHA (76 FR 43267, July 20, 2011), Table 3 in this Federal 
Register document provides Eglin AFB's estimates of the annual number 
of marine mammals, by species, potentially taken by Level B harassment, 
by the gunnery mission noise. It should be noted that these estimates 
are derived without consideration of the effectiveness of the required 
mitigation measures (except use of the TR), which are discussed earlier 
in this document. As indicated in Table 3, Eglin AFB and NMFS estimate 
that approximately 212 marine mammals may incur Level B (TTS) 
harassment annually. Because these gunnery exercises result in multiple 
detonations, they have the potential to also result in a temporary 
modification in behavior by marine mammals at levels below TTS. Based 
on Eglin AFB and NMFS' estimates, up to 694 marine mammals may 
experience a behavioral response to these exercises during the time 
frame of an IHA (see Table 3). Finally, while one would generally 
expect the threshold for behavioral modification to be lower than that 
causing TTS, due to a lack of empirical information and data, a dual 
criteria for Level B behavioral harassment cannot be developed. 
However, to ensure that takings are covered by this IHA, NMFS estimates 
that approximately 906 marine mammals of five stocks may incur Level B 
(harassment) takes during the 1-year period of an IHA. NMFS has 
determined that this number will be significantly lower due to the 
expected effectiveness of the mitigation measures required in the IHA.

            Table 3--Yearly Estimated Number of Marine Mammals Affected by the Gunnery Mission Noise
----------------------------------------------------------------------------------------------------------------
                                                      Level A         Level B                         Level B
                                     Adjusted       harassment    harassment non-     Level B     harassment non-
             Species                  Density      injurious 205   injurious 182  harassment non-  injurious 177
                                    (/    dB * EFD for    dB * EFD For    injurious 23    dB * EFD for
                                      km\2\)        ear rupture         TTS         psi For TTS      behavior
----------------------------------------------------------------------------------------------------------------
Bryde's whale...................             0.0             0.0             0.0             0.0             0.0
Sperm whale.....................             0.0             0.0             0.0             0.0             0.0
Dwarf/pygmy sperm whale.........             0.0             0.0             0.4             0.0             1.3
All beaked whales...............             0.0             0.0             0.0             0.0             0.0
Killer whale....................             0.0             0.0             0.0             0.0             0.0
Pygmy killer whale..............             0.0             0.0             0.0             0.0             0.0
False killer whale..............             0.0             0.0             0.0             0.0             0.0
Melon-headed whale..............             0.0             0.0             0.0             0.0             0.0
Short-finned pilot whale........             0.0             0.0             0.0             0.0             0.0
Rough-toothed dolphin...........             0.0             0.0             0.0             0.0             0.0
Bottlenose dolphin..............             0.6             0.0           134.9            17.8           442.9
Risso's dolphin.................             0.0             0.0             0.0             0.0             0.0

[[Page 62386]]

 
Atlantic spotted dolphin........             0.3             0.0            75.2             9.9           246.9
Pantropical spotted dolphin.....             0.1             0.0             0.3             0.0            11.1
Striped dolphin.................             0.0             0.0             0.0             0.0             0.2
Spinner dolphin.................             0.1             0.0             0.3             0.0             0.9
Clymene dolphin.................             0.0             0.0             0.1             0.0             0.3
Fraser's dolphin................             0.0             0.0             0.0             0.0             0.0
All marine mammals..............             1.3             0.0           211.5            27.9           694.2
----------------------------------------------------------------------------------------------------------------
km\2\ = square kilometers; NA = not applicable
* dB = dB re 1 [mu]Pa\2\-s.

Negligible Impact 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.
    No injuries or mortalities are anticipated to occur as a result of 
Eglin AFB's A-S gunnery mission activities, and none are authorized. 
Takes will be limited to Level B harassment in the form of behavioral 
disturbance and TTS. Although activities would be permitted to occur 
year-round and can last for approximately 5 to 6 hours at a time, the 
actual live-fire portion of the exercise usually only lasts for 90 to 
120 min; therefore, NMFS expects the duration of impacts to be 
relatively short. Additionally, it should also be noted that the actual 
level of activity has been far lower over the past few years than that 
predicted and estimated in this document. Those reasons were discussed 
earlier in this document. It is possible that some individuals may be 
taken more than once if those individuals are located in the exercise 
area on two different days when exercises are occurring. However, 
multiple exposures are not anticipated to have effects beyond Level B 
harassment.
    Of the 21 marine mammal species or stocks that may be in the 
vicinity of the EGTTR gunnery mission activities, only the sperm whale 
is listed as endangered under the ESA and as depleted under the MMPA. 
Sperm whale occurrence in the area of the proposed activity is unlikely 
because almost all reported sightings have occurred in water depths 
greater than 200 m. Occurrence in the deeper portions of W-151 is 
possible, although based on reported sighting locations, density is 
expected to be low. Therefore, Eglin AFB has not requested and NMFS has 
not issued take authorizations for this species. No mortality or injury 
is expected to occur and due to the nature, degree, and context of the 
Level B harassment anticipated, the activity is not expected to impact 
rates of recruitment or survival.
    Additionally, the mitigation and monitoring measures required to be 
implemented (described earlier in this document) are expected to 
minimize even further the potential for injury or mortality. The 
protected species surveys require Eglin AFB to search the area for 
marine mammals, and if any are found in the live fire area, then the 
exercise must be suspended until the animal(s) has left the area or the 
activity relocated. Moreover, the aircrews of the A-S gunnery missions 
will initiate location and surveillance of a suitable firing site 
immediately after exiting U.S. territorial waters (less than or equal 
to 12 nm (22 km)). This would potentially restrict most gunnery 
activities to the shallower continental shelf waters of the GOM where 
marine mammal densities are typically lower, and thus potentially avoid 
the slope waters where the more sensitive species (e.g., endangered 
sperm whales) typically reside.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the mitigation and monitoring 
measures, NMFS finds that Eglin AFB's A-S gunnery mission exercises 
will result in the incidental take of marine mammals, by Level B 
harassment only, and that the total taking from the A-S gunnery mission 
exercises will have a negligible impact on the affected species or 
stocks.

Impact on Availability of Affected Species or Stock for Taking for 
Subsistence Uses

    There are no relevant subsistence uses of marine mammals implicated 
by this action.

Endangered Species Act (ESA)

    A Biological Opinion issued by NMFS on October 20, 2004, concluded 
that the A-S gunnery exercises in the EGTTR are unlikely to jeopardize 
the continued existence of species listed under the ESA that are within 
the jurisdiction of NMFS or destroy or adversely modify critical 
habitat. NMFS has determined that this action, including the 
modifications to the mitigation and monitoring measures in the 2008 IHA 
and included in the 2010 IHA, does not have effects beyond that which 
was analyzed in that previous consultation, it is within the scope of 
that action, and reinitiation of consultation is not necessary.

National Environmental Policy Act (NEPA)

    The USAF prepared a Final PEA in November 2002 for the EGTTR 
activity. NMFS made the USAF's 2002 Final PEA available upon request on 
January 23, 2006 (71 FR 3474). In accordance with NOAA Administrative 
Order 216-6 (Environmental Review Procedures for Implementing the 
National Environmental Policy Act, May 20, 1999), NMFS reviewed the 
information contained in the USAF's 2002 Final PEA, and, on May 1, 
2006, determined that the document accurately and completely described 
the proposed action, the alternatives to the proposed action, and the 
potential impacts on marine mammals, endangered species, and other 
marine life that could be impacted by the preferred alternative and the 
other alternatives. Accordingly, NMFS adopted the USAF's 2002 Final PEA 
under 40 CFR 1506.3 and made its own FONSI on May 16, 2006. The

[[Page 62387]]

NMFS FONSI also took into consideration updated data and information 
contained in NMFS' Federal Register document noting issuance of an IHA 
to Eglin AFB for this activity (71 FR 27695, May 12, 2006), and 
previous notices (71 FR 3474, January 23, 2006; 70 FR 48675, August 19, 
2005).
    As the issuance of the 2008 IHA to Eglin AFB amended three of the 
mitigation measures for reasons of practicality and safety, NMFS 
reviewed the USAF's 2002 Final PEA and determined that a new EA was 
warranted to address: (1) The proposed modifications to the mitigation 
and monitoring measures; (2) the use of 23 psi as a change in the 
cr