[Federal Register Volume 76, Number 127 (Friday, July 1, 2011)]
[Notices]
[Pages 38621-38638]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-16606]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RIN 0648-XA343]


Takes of Marine Mammals Incidental to Specified Activities; 
Marine Geophysical Survey in the Western Gulf of Alaska, June to 
August, 2011

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

ACTION: Notice; issuance of an incidental take authorization (ITA).

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SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA) 
regulation, notification is hereby given that NMFS has issued an 
Incidental Harassment Authorization (IHA) to the Lamont-Doherty Earth 
Observatory of Columbia University (L-DEO) to take marine mammals, by 
Level B harassment, incidental to conducting a marine geophysical 
survey in the western Gulf of Alaska (GOA), June to August, 2011.

DATES: Effective June 28 to September 4, 2011.

ADDRESSES: A copy of the IHA and application are available by writing 
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 or by 
telephoning the contacts listed here.
    A copy of the application containing a list of the references used 
in this document may be obtained by writing to the above address, 
telephoning the contact listed here (see FOR FURTHER INFORMATION 
CONTACT) or visiting the Internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications. The following associated documents 
are also available at the same Internet address: ``Environmental 
Assessment of a Marine Seismic Survey in the Gulf of Alaska July-August 
2011'' (EA) prepared by the National Science Foundation (NSF), and 
``Environmental Assessment of a Marine Geophysical Survey by the R/V 
Marcus G. Langseth in the western Gulf of Alaska, July-August 2011,'' 
prepared by LGL Ltd., Environmental Research Associates (LGL), on 
behalf of NSF and L-DEO. The NMFS Biological Opinion will be available 
online at: http://www.nmfs.noaa.gov/pr/consultation/opinions.htm. 
Documents cited in this notice may be viewed, by appointment, during 
regular business hours, at the aforementioned address.

FOR FURTHER INFORMATION CONTACT: Howard Goldstein or Jolie Harrison, 
Office of Protected Resources, NMFS, 301-427-8401.

SUPPLEMENTARY INFORMATION: 

Background

    Section 101(a)(5)(D) of the MMPA (16 U.S.C. 1371 (a)(5)(D)) directs 
the Secretary of Commerce (Secretary) to authorize, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals of a species or population stock, by United States citizens who 
engage in a specified activity (other than commercial fishing) within a 
specified geographical region if

[[Page 38622]]

certain findings are made and, if the taking is limited to harassment, 
a notice of a proposed authorization is provided to the public for 
review.
    Authorization for the incidental taking of small numbers of marine 
mammals 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 takings. 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 United States can apply for an authorization 
to incidentally take small numbers of marine mammals by harassment. 
Section 101(a)(5)(D) of the MMPA establishes a 45-day time limit for 
NMFS's review of an application followed by a 30-day public notice and 
comment period on any proposed authorizations for the incidental 
harassment of small numbers of marine mammals. Within 45 days of the 
close of the public comment period, NMFS must either issue or deny the 
authorization.
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as:

    any act of pursuit, torment, or annoyance which (i) has the 
potential to injure a marine mammal or marine mammal stock in the 
wild [Level A harassment]; or (ii) has the potential to disturb a 
marine mammal or marine mammal stock in the wild by causing 
disruption of behavioral patterns, including, but not limited to, 
migration, breathing, nursing, breeding, feeding, or sheltering 
[Level B harassment].

16 U.S.C. 1362(18).

Summary of Request

    NMFS received an application on April 1, 2010, from L-DEO for the 
taking by harassment, of marine mammals, incidental to conducting a 
marine geophysical survey in the western GOA within the U.S. Exclusive 
Economic Zone (EEZ) in depths from approximately 25 meters (m) (82 feet 
[ft]) to greater than 6,000 m (19,685 ft). The cruise was postponed in 
2010 and rescheduled for 2011. NMFS received a revised application on 
March 4, 2011 from L-DEO. L-DEO plans to conduct the survey from 
approximately June 28 to August 4, 2011. On May 6, 2011, NMFS published 
a notice in the Federal Register (76 FR 26255) disclosing the effects 
on marine mammals, making preliminary determinations and including a 
proposed IHA. The notice initiated a 30 day public comment period.
    L-DEO plans to use one source vessel, the R/V Marcus G. Langseth 
(Langseth) and a seismic airgun array to collect seismic reflection and 
refraction profiles from the Shumagin Islands to east of Kodiak Island 
in the GOA. In addition to the operations of the seismic airgun array, 
L-DEO intends to operate a multibeam echosounder (MBES) and a sub-
bottom profiler (SBP) continuously throughout the survey.
    Acoustic stimuli (i.e., increased underwater sound) generated 
during the operation of the seismic airgun array may have the potential 
to cause a short-term behavioral disturbance for marine mammals in the 
survey area. This is the principal means of marine mammal taking 
associated with these activities and L-DEO has requested an 
authorization to take 16 species of marine mammals by Level B 
harassment. Take is not expected to result from the use of the MBES or 
SBP, for reasons discussed in this notice; nor is take expected to 
result from collision with the vessel because it is a single vessel 
moving at a relatively slow speed during seismic acquisition within the 
survey, for a relatively short period of time (approximately 38 days). 
It is likely that any marine mammal would be able to avoid the vessel.

Description of the Specified Activity

    L-DEO's planned seismic survey in the western GOA, from the 
Shumagin Islands to east of Kodiak Island, will take place during June 
to August, 2011, in the area 52.5[deg] to 59[deg] North, 147.5[deg] to 
161[deg] West (see Figure 1 of the IHA application). The seismic survey 
will take place in water depths ranging from 25 m (82 ft) to greater 
than 6,000 m (82 to 19,685 ft) and consists of approximately 2,553 
kilometers (km) (1,378.5 nautical miles [nmi]) of transect lines in the 
study area. The project is scheduled to occur from approximately June 
28 to August 4, 2011. Some minor deviation from these dates is 
possible, depending on logistics and weather.
    The seismic survey will collect seismic reflection and refraction 
data to characterize the subduction zone off southern Alaska, which 
produces large and destructive earthquakes. The data from this study 
will be used to: (1) Estimate the size of the seismogenic zone, the 
portion of the fault that controls the magnitude of earthquakes, and 
(2) provide critical information on how the properties of the 
seismogenic zone change along the subduction zone such that some areas 
produce large earthquakes and others do not. The study focuses on the 
Semidi segment, whose earthquake recurrence interval is 50 to 75 years 
and which last ruptured in 1938.
    The survey will involve one source vessel, the Langseth. The 
Langseth will deploy an array of 36 airguns as an energy source at a 
tow depth of 12 m (39.4 ft). The receiving system will consist of two 8 
km (4.3 nmi) long hydrophone streamers and/or 21 ocean bottom 
seismometers (OBSs). As the airguns are towed along the survey lines, 
the hydrophone streamers will receive the returning acoustic signals 
and transfer the data to the on-board processing system. The OBSs 
record the returning acoustic signals internally for later analysis.
    The planned seismic survey (e.g., equipment testing, startup, line 
changes, repeat coverage of any areas, and equipment recovery) will 
consist of approximately 2,553 km of transect lines in the western GOA 
survey area (see Figure 1 of the IHA application). Just over half of 
the survey (1,363 km [736 nmi]) will take place in water deeper than 
1,000 m; 30% or 754 km (407.1 nmi) will be surveyed in intermediate 
depth (100 to 1,000 m) water; and 17% (463 km [250 nmi]) will take 
place in water less than 100 m deep. Approximately 30 km (16.2 nmi) of 
seismic surveying will occur in water less than 40 m deep. A refraction 
survey using OBSs will take place along two lines (lines 3 and 5). 
Following the refraction survey, a multichannel (MCS) survey using two 
hydrophone streamers will take place along all of the transect lines. 
Thus, lines three and five will be surveyed twice. In addition to the 
operations of the airgun array, a Kongsberg EM 122 MBES and Knudsen 
320B SBP will also be operated from the Langseth continuously 
throughout the cruise. There will be additional seismic operations 
associated with equipment testing, start-up, and possible line changes 
or repeat coverage of any areas where initial data quality is sub-
standard. In L-DEO's calculations, 25% has been added for those 
additional operations.
    All planned geophysical data acquisition activities will be 
conducted by L-DEO, the Langseth's operator, with on-board assistance 
by the scientists

[[Page 38623]]

who have planned the study. The Principal Investigators are Drs. Donna 
Shillington, Spahr Webb, and Mladen Nedimovic, all of L-DEO. The vessel 
will be self-contained, and the crew will live aboard the vessel for 
the entire cruise.

Description of the Dates, Duration, and Specified Geographic Region

    The survey will occur in the western GOA in the area 52.5[deg] to 
59[deg] North, 147.5 to 161[deg] West. The seismic survey will take 
place in water depths of 25 m to greater than 6,000 m. The Langseth 
will depart from Kodiak, Alaska on approximately June 28, 2011. The 
program will start with a refraction survey using OBSs. Approximately 
21 OBSs will be deployed along one line; the OBSs will then be 
retrieved and re-deployed along the next refraction line. OBS 
deployment will take approximately three days and recovery will take 
approximately five days; there will be a total of approximately three 
days of refraction shooting. Following the refraction survey, the MCS 
survey will take place using the two streamers. MCS and airgun 
deployment will take approximately three days, and there will be 
approximately 13 days of MCS operations. Upon completion of seismic 
operations, all gear will be picked up and the vessel will travel to 
Dutch Harbor, for arrival on approximately August 4, 2011. Seismic 
operations in the study area will be carried out for approximately 16 
days. Some minor deviation from this schedule is possible, depending on 
logistics and weather (i.e., the cruise may depart earlier or be 
extended due to poor weather; there could be an additional three days 
of seismic operations if collected data are deemed to be of substandard 
quality).
    NMFS outlined the purpose of the program in a previous notice for 
the proposed IHA (76 FR 26255, May 6, 2011). The activities to be 
conducted have not changed between the proposed IHA notice and this 
final notice announcing the issuance of the IHA. For a more detailed 
description of the authorized action, including vessel and acoustic 
source specifications, the reader should refer to the proposed IHA 
notice (76 FR 26255, May 6, 2011), the IHA application, EA, and 
associated documents referenced above this section.

Comments and Responses

    A notice of receipt of the L-DEO application and proposed IHA was 
published in the Federal Register on May 6, 2011 (76 FR 26255). During 
the 30-day public comment period, NMFS received comments from the 
Marine Mammal Commission (Commission) only. The Commission's comments 
are online at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm.
    Following are their comments and NMFS's responses:
    Comment 1: The Commission recommends that the NMFS require L-DEO to 
re-estimate the proposed exclusion (EZs) and buffer zones and 
associated takes of marine mammals using site-specific information.
    Response: NMFS is satisfied that the data supplied are sufficient 
for NMFS to conduct its analysis and make any determinations and 
therefore no further effort is needed by the applicant. While exposures 
of marine mammals to acoustic stimuli are difficult to estimate, NMFS 
is confident that the levels of take provided by L-DEO in their IHA 
application and EA, and authorized herein are estimated based upon the 
best available scientific information and estimation methodology.
    The alternative method of conducting site-specific attenuation 
measurements in the water depths that the survey is to be conducted is 
neither warranted nor practical for the applicant. Site signature 
measurements are normally conducted commercially by shooting a test 
pattern over an ocean bottom instrument in shallow water. This method 
is neither practical nor valid for this survey which will occur in 
water depths as great as 6,000 m (19,685 ft). The alternative method of 
conducting site-specific attenuation measurements would require a 
second vessel, which is impractical both logistically and financially. 
Sound propagation varies notably less between deep water sites than it 
would between shallow water sites (because of the reduced significance 
of bottom interaction), thus decreasing the importance of deep water 
site-specific estimates.
    Should the applicant endeavor to undertake a sound source 
verification study, confidence in the results is necessary in order to 
ensure for conservation purposes that appropriate monitoring and 
mitigation measures are implemented; therefore inappropriate or poorly 
executed efforts should be avoided and discouraged.
    Source signature modeling is preferable in this instance because:
    (1) The results can be reviewed and independently verified;
    (2) Site-specific measurements are subject to numerous sources of 
error; and
    (3) Reliable site-specific measurements require specialized 
equipment (calibrated hydrophones) and acoustic specialists to conduct 
the tests and interpret the results.
    The 160 dB (i.e., buffer) zone used to estimate exposure is 
appropriate and sufficient for purposes of supporting NMFS's analysis 
and determinations required under section 101(a)(5)(D) of the MMPA and 
its implementing regulations. See NMFS's responses to Comment 2 (below) 
for additional details.
    Comment 2: The Commission recommends that NMFS require L-DEO, if 
the EZs and buffer zones and takes are not re-estimated, to provide a 
detailed justification (1) For basing the EZs and buffer zones for the 
proposed survey in the GOA on empirical data collected in the Gulf of 
Mexico (GOM) or on modeling that relies on measurements from the GOM 
and (2) that explains why simple ratios were used to adjust for tow 
depth and median values were applied to intermediate water depths 
rather than using empirical measurements.
    Response: As stated earlier, NMFS is not requiring L-DEO to re-
estimate the EZs and 160 dB zones for this survey. L-DEO provides a 
detailed description on how they estimated EZs, 160 dB zones, and take 
estimates in Appendix A of the EA, which includes information from the 
calibration study conducted on the Langseth in 2007 and 2008. Appendix 
A describes L-DEO's modeling process and compares the model results 
with empirical results of the 2007 and 2008 Langseth calibration 
experiment in shallow, intermediate, and deep water. The conclusions 
identified in Appendix A show that the model represents the actual 
produced levels, particularly within the first few kms, where the 
predicted EZs lie. At greater distances, local oceanographic variations 
begin to take effect, and the model tends to over predict sound 
attenuation. Further, since the modeling matches the observed 
measurement data, the authors have concluded that the models can 
continue to be used for defining EZs, including for predicting 
mitigation radii for various tow depths. The data results from the 
studies were peer reviewed and the calibration results, viewed as 
conservative, were used to determine the cruise-specific EZs. This 
information is now available in the final EA on NSF's Web site at 
http://www.nsf.gov/geo/oce/envcomp/index.jsp.
    At present, the L-DEO model does not account for site-specific 
environmental conditions. The calibration study of the L-DEO model 
predicted that using site-specific information may actually provide 
less conservative EZs at greater distances. The ``Draft Programmatic 
Environmental Impact Statement for Marine Seismic Research Funded by 
the National Science Foundation or

[[Page 38624]]

Conducted by the U.S. Geological Survey'' (DPEIS) prepared pursuant to 
the National Environmental Policy Act (NEPA; 42 U.S.C. et seq.) did 
incorporate various site-specific environmental conditions in the 
modeling of the Detailed Analysis Areas. The NEPA process associated 
with the DPEIS is still ongoing and the USGS and NSF have not yet 
issued a Record of Decision. Once the NEPA process for the PEIS has 
concluded, NSF will look at upcoming cruises on a site-specific basis 
for any impacts not already considered in the DPEIS.
    The IHA issued to L-DEO, under section 101(a)(5)(D) of the MMPA 
provides monitoring and mitigation requirements that will protect 
marine mammals from injury, serious injury, or mortality. L-DEO is 
required to comply with the IHA's requirements. These analyses are 
supported by extensive scientific research and data. NMFS is confident 
in the peer-reviewed results of the L-DEO seismic calibration studies 
which, although viewed as conservative, are used to determine cruise-
specific EZs and which factor into exposure estimates. NMFS has 
determined that these reviews are the best scientific data available 
for review of the IHA application and to support the necessary analyses 
and determinations under the MMPA, Endangered Species Act (ESA; 16 
U.S.C. 1531 et seq.) and NEPA.
    Based on NMFS's analysis of the likely effects of the specified 
activity on marine mammals and their habitat, NMFS has determined that 
the EZs identified in the IHA are appropriate for the survey and that 
additional field measurement is not necessary at this time. While 
exposures of marine mammals to acoustic stimuli are difficult to 
estimate, NMFS is confident that the levels of take authorized herein 
are estimated based upon the best available scientific information and 
estimation methodology. The 160 dB zone used to estimate exposure are 
appropriate and sufficient for purposes of supporting NMFS's analysis 
and determinations required under section 101(a)(5)(D) of the MMPA and 
its implementing regulations.
    Comment 3: The Commission recommends that NMFS require that L-DEO 
use species-specific maximum densities rather than best densities to 
re-estimate the anticipated number of takes.
    Response: NMFS acknowledges the Commission's recommendation and is 
currently evaluating the recommendation to use species-specific maximum 
densities versus best densities to estimate the anticipated number of 
takes for marine mammals to determine a standard approach. However, for 
purposes of this IHA, NMFS is using the best (i.e., average or mean) 
densities to estimate the number of authorized takes for L-DEO's 
seismic survey in the western GOA as NMFS is confident in the 
assumptions and calculations used to estimate density for this survey 
area. NMFS Endangered Species Division generally uses the best estimate 
when analyzing the allowable take for Endangered Species Act-listed 
threatened and endangered marine mammals in Biological Opinion's (BiOp) 
and Incidental Take Statements (ITS) incidental to marine seismic 
surveys for scientific research purposes. Contrary to the Commission's 
comment (above), NMFS has used best densities to estimate the number of 
incidental takes in IHAs for several seismic surveys in the past. The 
results of the associated monitoring reports show that the use of the 
best estimates is appropriate for and does not refute NMFS's 
determinations.
    Comment 4: The Commission recommends that if NMFS is planning to 
allow the applicant to resume full power after nine minutes (min) under 
certain circumstances, specify in the authorization in all conditions 
under which a nine min period could be followed by a full-power 
resumption of the airguns.
    Response: During periods of active seismic operations, there are 
occasions when the airguns need to be temporarily shut-down (for 
example due to equipment failure, maintenance, or shut-down) or a 
power-down is necessary (for example when a marine mammal is seen to 
either enter or about to enter the EZ). In these instances, should the 
airguns be inactive or powered-down for more than nine min, then L-DEO 
would follow the ramp-up procedures identified in the Mitigation 
section (see below) where airguns will be re-started beginning with the 
smallest airgun in the array and increase in steps not to exceed 6 dB 
per 5 min over a total duration of approximately 30 min. NMFS and NSF 
believe that the nine min period in question is an appropriate minimum 
amount of time to pass after which a ramp-up process should be 
followed. In these instances, should it be possible for the airguns to 
be re-activated without exceeding the nine min period (for example 
equipment is fixed or a marine mammal is visually observed to have left 
the EZ for the full source level), then the airguns would be 
reactivated to the full operating source level identified for the 
survey (in this case, 6,600 in\3\) without need for initiating ramp-up 
procedures. In the event a marine mammal enters the EZ and a power-down 
is initiated, and the marine mammal is not visually observed to have 
left the EZ, then L-DEO must wait 15 min (for species with shorter dive 
durations--small odontocetes and pinnipeds) or 30 min (for species with 
longer dive durations--mysticetes and large odontocetes) after the last 
sighting before ramp-up procedures can be initiated, or as otherwise 
directed by requirements in an IHA. However, ramp-up will not occur as 
long as a marine mammal is detected within the EZ, which provides more 
time for animals to leave the EZ, and accounts for the position, swim 
speed, and heading of marine mammals within the EZ.
    Comment 5: The Commission recommends that NMFS extend the 30 min 
period following a marine mammal sighting in the EZ to cover the full 
dive times of all species likely to be encountered.
    Response: NMFS recognizes that several species of deep-diving 
cetaceans are capable of remaining underwater for more than 30 min 
(e.g., sperm whales, Cuvier's beaked whales, Baird's beaked whales, and 
Stejneger's beaked whales); however, for the following reasons NMFS 
believes that 30 min is an adequate length of the monitoring period 
prior to the ramp-up of airguns:
    (1) Because the Langseth is required to monitor before ramp-up of 
the airgun array, the time of monitoring prior to the start-up of any 
but the smallest array is effectively longer than 30 min (ramp-up will 
begin with the smallest airgun in the array and airguns will be added 
in sequence such that the source level of the array will increase in 
steps not exceeding approximately 6 dB per 5 min period over a total 
duration of 20 to 30 min;
    (2) In many cases PSVOs are observing during times when L-DEO is 
not operating the seismic airguns and would observe the area prior to 
the 30 min observation period;
    (3) The majority of the species that may be exposed do not stay 
underwater more than 30 min; and
    (4) All else being equal and if deep-diving individuals happened to 
be in the area in the short time immediately prior to the pre-ramp up 
monitoring, if an animal's maximum underwater dive time is 45 min, then 
there is only a one in three chance that the last random surfacing 
would occur prior to the beginning of the required 30 min monitoring 
period and that the animal would not be seen during that 30 min period.
    Finally, seismic vessels are moving continuously (because of the 
long, towed array and streamer) and NMFS

[[Page 38625]]

believes that unless the animal submerges and follows at the speed of 
the vessel (highly unlikely, especially when considering that a 
significant part of their movement is vertical [deep-diving]), the 
vessel will be far beyond the length of the EZ within 30 min, and 
therefore it will be safe to start the airguns again.
    The effectiveness of monitoring is science-based and the 
requirement that monitoring and mitigation measures be ``practicable.'' 
NMFS believes that the framework for visual monitoring will: (1) Be 
effective at spotting almost all species for which take is requested; 
and (2) that imposing additional requirements, such as those suggested 
by the Commission, would not meaningfully increase the effectiveness of 
observing marine mammals approaching or entering the EZs and thus 
further minimize the potential for take.
    Comment 6: The Commission recommends that NMFS, prior to granting 
the requested authorization, provide additional justification for its 
preliminary determination that the proposed monitoring program will be 
sufficient to detect, with a high level of confidence, all marine 
mammals within or entering the identified EZs and buffer zones, 
including
    (1) Identifying those species that it believes can be detected with 
a high degree of confidence using visual monitoring only,
    (2) Describing detection probability as a function of distance from 
the vessel,
    (3) Describing changes in detection probability under various sea 
state and weather conditions and light levels, and
    (4) Explaining how close to the vessel marine mammals must be for 
Protected Species Observers (PSOs) to achieve high nighttime detection 
rates.
    Response: NMFS believes that the planned monitoring program will be 
sufficient to detect (using visual monitoring and passive acoustic 
monitoring [PAM]), with reasonable certainty, marine mammals within or 
entering identified EZs. This monitoring, along with the required 
mitigation measures, will result in the least practicable adverse 
impact on the affected species or stocks and will result in a 
negligible impact on the affected species or stocks of marine mammals. 
Also, NMFS expects some animals to avoid areas around the airgun array 
ensonified at the level of the EZ.
    NMFS acknowledges that the detection probability for certain 
species of marine mammals varies depending on animal's size and 
behavior as well as sea state and weather conditions and light levels. 
The detectability of marine mammals likely decreases in low light 
(i.e., darkness), higher Beaufort sea states and wind conditions, and 
poor weather (e.g., fog and/or rain). However, at present, NMFS views 
the combination of visual monitoring and PAM as the most effective 
monitoring and mitigation techniques available for detecting marine 
mammals within or entering the EZ. The final monitoring and mitigation 
measures are the most effective feasible measures and NMFS is not aware 
of any additional measures which could meaningfully increase the 
likelihood of detecting marine mammals in and around the EZ. Further, 
public comment has not revealed any additional monitoring or mitigation 
measures that could be feasibly implemented to increase the 
effectiveness of detection.
    NSF and L-DEO are receptive to incorporating proven technologies 
and techniques to enhance the current monitoring and mitigation 
program. Until proven technological advances are made, nighttime 
mitigation measures during operations include combinations of the use 
of PSVOs for ramp-ups, PAM, night vision devices (NVDs), and continuous 
shooting of a mitigation airgun. Should the airgun array be powered-
down, the operation of a single airgun would continue to serve as a 
sound source deterrent to marine mammals. In the event of a complete 
shut-down of the airgun array at night for mitigation or repairs, L-DEO 
suspends the data collection until one-half hour after nautical 
twilight-dawn (when PSVO's are able to clear the EZ). L-DEO will not 
activate the airguns until the entire EZ is visible for at least 30 
min.
    In cooperation with NMFS, L-DEO will be conducting efficacy 
experiments of NVDs during a future Langseth cruise. In addition, in 
response to a recommendation from NMFS, L-DEO is evaluating the use of 
handheld forward-looking thermal imaging cameras to supplement 
nighttime monitoring and mitigation practices. During other low power 
seismic and seafloor mapping surveys, L-DEO successfully used these 
devices while conducting nighttime seismic operations.
    Comment 7: The Commission recommends that NMFS consult with the 
funding agency (i.e., NSF) and individual applicants (e.g., L-DEO and 
U.S. Geological Survey [USGS]) to develop, validate, and implement a 
monitoring program that provides a scientifically sound, reasonably 
accurate assessment of the types of marine mammal taking and number of 
marine mammals taken.
    Response: Numerous studies have reported on the abundance and 
distribution of marine mammals inhabiting the GOA, which overlaps with 
the seismic survey area, and L-DEO has incorporated this data into 
their analyses used to predict marine mammal take in their application. 
NMFS believes that L-DEO's current approach for estimating abundance in 
the survey area (prior to the survey) is the best available approach.
    There will be significant amounts of transit time during the 
cruise, and PSVOs will be on watch prior to and after the seismic 
portions of the survey, in addition to during the survey. The 
collection of this visual observational data by PSVOs may contribute to 
baseline data on marine mammals (presence/absence) and provide some 
generalized support for estimated take numbers, but it is unlikely that 
the information gathered from this single cruise along would result in 
any statistically robust conclusions for any particular species because 
of the small number of animals typically observed.
    NMFS acknowledges the Commission's recommendations and is open to 
further coordination with the Commission, NSF (the vessel owner), and 
L-DEO (the ship operator on behalf of NSF), to develop, validate, and 
implement a monitoring program that will provide or contribute towards 
a more scientifically sound and reasonably accurate assessment of the 
types of marine mammal taking and the number of marine mammals taken. 
However, the cruise's primary focus is marine geophysical research and 
the survey may be operationally limited due to considerations such as 
location, time, fuel, services, and other resources.
    Comment 8: The Commission recommends that NMFS require the 
applicant to
    (1) Report on the number of marine mammals that were detected 
acoustically and for which a power-down or shut-down of the airguns was 
initiated;
    (2) Specify if such animals also were detected visually; and
    (3) Compare the results from the two monitoring methods (visual 
versus acoustic) to help identify their respective strengths and 
weaknesses.
    Response: The IHA requires that PSAOs on the Langseth do and record 
the following when a marine mammal is detected by the PAM:
    (i) Notify the on-duty PSVO(s) immediately of a vocalizing marine 
mammal so a power-down or shut-down can be initiated, if required;
    (ii) Enter the information regarding the vocalization into a 
database. The

[[Page 38626]]

data to be entered include an acoustic encounter identification number, 
whether it was linked with a visual sighting, date, time when first and 
last heard and whenever any additional information was recorded, 
position, and water depth when first detected, bearing if determinable, 
species or species group (e.g., unidentified dolphin, sperm whale), 
types and nature of sounds heard (e.g., clicks, continuous, sporadic, 
whistles, creaks, burst pulses, strength of signal, etc.), and any 
other notable information.
    L-DEO reports on the number of acoustic detections made by the PAM 
system within the post-cruise monitoring reports as required by the 
IHA. The report also includes a description of any acoustic detections 
that were concurrent with visual sightings, which allows for a 
comparison of acoustic and visual detection methods for each cruise.
    The post-cruise monitoring reports also include the following 
information: the total operational effort in daylight (hrs), the total 
operational effort at night (hrs), the total number of hours of visual 
observations conducted, the total number of sightings, and the total 
number of hours of acoustic detections conducted.
    LGL Ltd., Environmental Research Associates (LGL), a contractor for 
L-DEO, has processed sighting and density data, and their publications 
can be viewed online at: http://www.lgl.com/index.php?option=com_content&view=article&id=69&Itemid=162⟨=en. Post-cruise monitoring 
reports are currently available on the NMFS's MMPA Incidental Take 
Program Web site on the NSF Web site (http://www.nsf.gov/geo/oce/envcomp/index.jsp) should there be interest in further analysis of this 
data by the public.
    Comment 9: The Commission recommends that NMFS condition the 
authorization to require the L-DEO to monitor, document, and report 
observations during all ramp-up procedures.
    Response: The IHA requires that PSVOs on the Langseth make 
observations for 30 min prior to ramp-up, during all ramp-ups, and 
during all daytime seismic operations and record the following 
information when a marine mammal is sighted:
    (i) Species, group size, age/size/sex categories (if determinable), 
behavior when first sighted and after initial sighting, heading (if 
consistent), bearing and distance from seismic vessel, sighting cue, 
apparent reaction of the airguns or vessel (e.g., none, avoidance, 
approach, paralleling, etc., and including responses to ramp-up), and 
behavioral pace; and
    (ii) Time, location, heading, speed, activity of the vessel 
(including number of airguns operating and whether in state of ramp-up 
or power-down), Beaufort wind force and sea state, visibility, and sun 
glare.
    Comment 10: The Commission recommends that NMFS work with NSF to 
analyze these monitoring data to help determine the effectiveness of 
ramp-up procedures as a mitigation measure for geophysical surveys 
after the data are compiled and quality control measures have been 
completed.
    Response: One of the primary purposes of monitoring is to result in 
``increased knowledge of the species'' and the effectiveness of 
monitoring and mitigation measures; the effectiveness of ramp-up as a 
mitigation measure and marine mammal reaction to ramp-up would be 
useful information in this regard. NMFS has asked NSF and L-DEO to 
gather all data that could potentially provide information regarding 
the effectiveness of ramp-ups as a mitigation measure. However, 
considering the low numbers of marine mammal sightings and low numbers 
of ramp-ups, it is unlikely that the information will result in any 
statistically robust conclusions for this particular seismic survey. 
Over the long term, these requirements may provide information 
regarding the effectiveness of ramp-up as a mitigation measure, 
provided animals are detected during ramp-up.
    Comment 11: The Commission recommends that NMFS condition the IHA 
to require L-DEO to (1) report immediately all injured or dead marine 
mammals to NMFS and (2) suspend the geophysical survey if a marine 
mammal is seriously injured or killed and the injury or death could 
have been caused by the survey (e.g., a fresh dead carcass); if 
additional measures are not likely to reduce the risk of additional 
serious injuries or deaths to a very low level, require L-DEO to obtain 
the necessary authorization for such takings under section 101(a)(5)(A) 
of the MMPA before allowing it to continue this survey or initiate 
additional surveys.
    Response: As stipulated in the IHA, in the unanticipated event that 
the specified activity clearly causes the take of a marine mammal in a 
manner prohibited by the IHA, such as an injury (Level A harassment), 
serious injury or mortality (e.g., ship-strike, gear interaction, and/
or entanglement), L-DEO will immediately cease the specified activities 
and immediately report the incident to the Chief of the Permits, 
Conservation, and Education Division, Office of Protected Resources, 
NMFS at 301-427-8401 and/or by e-mail to [email protected] and 
[email protected], and the Alaska Regional Stranding 
Coordinators ([email protected] and [email protected]). The 
incident report must include the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Name and type of vessel involved;
     Vessel's speed during and leading up to the incident;
     Description of the incident;
     Status of all sound source use in the 24 hours preceding 
the incident;
     Water depth;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS shall work with L-DEO to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. L-DEO may not resume their 
activities until notified by NMFS via letter or e-mail, or telephone.
    In the event that L-DEO discovers an injured or dead marine mammal, 
and the lead PSO determines that the cause of the injury or death is 
unknown and the death is relatively recent (i.e., in less than a 
moderate state of decomposition as described in the next paragraph), L-
DEO will immediately report the incident to the Chief of the Permits, 
Conservation, and Education Division, Office of Protected Resources, 
NMFS, at 301-427-8401, and/or by e-mail to [email protected] and 
[email protected], and the NMFS Alaska Stranding Hotline (1-
877-925-7773) and/or by e-mail to the Alaska Regional Stranding 
Coordinators ([email protected] and [email protected]). The 
report must include the same information identified in the paragraph 
above. Activities may continue while NMFS reviews the circumstances of 
the incident. NMFS will work with L-DEO to determine whether 
modifications in the activities are appropriate.
    In the event that L-DEO discovers an injured or dead marine mammal, 
and the lead PSO determines that the injury or death is not associated 
with or related

[[Page 38627]]

to the activities authorized in the IHA (e.g., previously wounded 
animal, carcass with moderate to advanced decomposition, or scavenger 
damage), L-DEO will report the incident to the Chief of the Permits, 
Conservation, and Education Division, Office of Protected Resources, 
NMFS, at 301-427-8401, and/or by e-mail to [email protected] and 
[email protected], and the NMFS Alaska Stranding Hotline (1-
877-925-7773), and/or by e-mail to the Alaska Regional Stranding 
Coordinators ([email protected] and [email protected]), 
within 24 hours of discovery. L-DEO will provide photographs or video 
footage (if available) or other documentation of the stranded animal 
sighting to NMFS and the Marine Mammal Stranding Network.

Description of the Marine Mammals in the Area of the Specified Activity

    Twenty-five marine mammal species (18 cetacean, 6 pinniped, and the 
sea otter) are known to or could occur in the GOA study area. Several 
of these species are listed as endangered under the U.S. Endangered 
Species Act of 1973 (ESA; 16 U.S.C. 1531 et seq.), including the North 
Pacific right (Eubalaena japonica), humpback (Megaptera novaeangliae), 
sei (Balaenoptera borealis), fin (Balaenoptera physalus), blue 
(Balaenoptera musculus), and sperm (Physeter macrocephalus) whales, as 
well as the Cook Inlet distinct population segment (DPS) of beluga 
whales (Dephinapterus leucas) and the western stock of Steller sea 
lions (Eumetopias jubatus). The eastern stock of Steller sea lions is 
listed as threatened, as is the southwest Alaska DPS of the sea otter 
(Enhydra lutris).
    The marine mammals that occur in the survey area belong to four 
taxonomic groups: odontocetes (toothed cetaceans, such as dolphins), 
mysticetes (baleen whales), pinnipeds (seals, sea lions, and walrus), 
and fissipeds (sea otter). Cetaceans and pinnipeds are the subject of 
the IHA application to NMFS. Walrus sightings are rare in the GOA. Sea 
otters generally inhabit nearshore areas inside the 40 m (131.2 ft) 
depth contour (Riedman and Estes, 1990) and could be encountered in 
coastal waters, but likely would not be encountered in the deep, 
offshore waters of the study area. The sea otter and Pacific walrus are 
two marine mammal species mentioned in this document that are managed 
by the U.S. Fish and Wildlife Service (USFWS) and are not considered 
further in this analysis; all others are managed by NMFS. The Cook 
Inlet DPS of beluga whales, California sea lions (Zalophus c. 
californianus), northern fur seals (Callorhinus ursinus), and northern 
elephant seals (Mirounga angustirostris) are not likely to be found in 
the waters of the survey area.
    Table 1 presents information on the abundance, distribution, 
population status, conservation status, and density of the marine 
mammals that may occur in the survey area during June to August, 2011.

Table 1--The Habitat, Regional Abundance, and Conservation Status of Marine Mammals That May Occur In or Near the Seismic Survey Area in the Western GOA
                                     [See text and tables 2 to 4 in L-DEO's application and EA for further details.]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                        Density  (/1,000 km\2\)
                                                                                                                                             shallow
                                Occurrence in/                         Abundance         Regional                                         intermediate
           Species               near  survey         Habitat          (Alaska)         abundance         ESA \1\          MMPA \2\           deep
                                     area                                                                                              -----------------
                                                                                                                                          Best
                                                                                                                                          \3\    Max \4\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mysticetes:
    North Pacific right whale  Rare............  Coastal, shelf..  28-31 \5\.......  Low hundreds     EN.............  D..............        0        0
     (Eubalaena japonica).                                                            \6\.                                                    0        0
                                                                                                                                              0        0
    Gray whale (Eschrichtius   Uncommon........  Coastal.........  N.A.............  19,126 \7\.....  DL.............  NC.............        0        0
     robustus).                                                                                       EN (Western      D (Western             0        0
                                                                                                       pop.).           pop.).                0        0
    Humpback whale (Megaptera  Common..........  Coastal, banks..  3,000 to 5,000    20,800 \9\.....  EN.............  D..............    40.90     66.0
     novaeangliae).                                                 \8\.                                                                  12.69     66.0
                                                                                                                                           2.61     6.53
    Minke whale (Balaenoptera  Uncommon........  Coastal, shelf..  1,233 \10\......  25,000 \11\....  NL.............  NC.............     1.40      6.0
     acutorostrata).                                                                                                                       0.31      6.0
                                                                                                                                              0        0
    Sei whale (Balaenoptera    Rare............  Pelagic.........  N.A.............  7,260 to 12,620  EN.............  D..............        0        0
     borealis).                                                                       \12\.                                                   0        0
                                                                                                                                              0        0
    Fin whale (Balaenoptera    Common..........  Pelagic.........  1,652 \10\......  13,620 to        EN.............  D..............    10.62     40.0
     physalus).                                                                       18,680.\13\                                         12.61     40.0
                                                                                                                                           2.90    10.38
    Blue whale (Balaneoptera   Rare............  Pelagic, shelf,   N.A.............  3,500 \14\.....  EN.............  D..............        0        0
     musculus).                                   coastal.                                                                                    0        0
                                                                                                                                              0        0
Odontocetes:
    Sperm whale (Physeter      Uncommon........  Pelagic.........  159 \15\........  24,000 \16\....  EN.............  D..............        0        0
     macrocephalus).                                                                                                                       0.11     0.26
                                                                                                                                           0.38     1.69
    Cuvier's beaked whale      Common..........  Pelagic.........  N.A.............  20,000 \17\....  NL.............  NC.............        0        0
     (Ziphius cavirostris).                                                                                                                1.12     1.81
                                                                                                                                              0        0
    Baird's beaked whale       Rare............  Pelagic.........  N.A.............  6,000 \18\.....  NL.............  NC.............        0        0
     (Berardius bairdii).                                                                                                                  0.37     0.60
                                                                                                                                              0        0
    Stejneger's beaked whale   Common..........  Likely pelagic..  N.A.............  N.A............  NL.............  NC.............        0        0
     (Mesoplodon stejnegeri).                                                                                                                 0        0
                                                                                                                                              0        0
    Beluga whale               Rare............  Coastal and ice   340 \19\........  N.A............  EN \34\........  D \34\.........        0        0
     (Delphinapterus leucas).                     edges.                                              NL.............  NC.............        0        0
                                                                                                                                              0        0

[[Page 38628]]

 
    Pacific white-sided        Common..........  Pelagic, shelf,   26,880 \20\.....  988,000 \21\...  NL.............  NC.............     2.08     4.76
     dolphin (Lagenorhynchus                      coastal.                                                                                 3.96    14.36
     obliquidens).                                                                                                                            0        0
    Risso's dolphin (Grampus   Rare............  Pelagic, shelf,   N.A.............  838,000 \22\...  NL.............  NC.............        0        0
     griseus).                                    coastal.                                                                                    0        0
                                                                                                                                              0        0
    Killer whale (Orcinus      Common..........  Pelagic, shelf,   2,636 \23\......  8,500 \24\.....  NL \35\........  NC.............     7.26    41.80
     orca).                                       coastal.                                                                                 7.34    41.80
                                                                                                                                           3.79    13.53
    Short-finned pilot whale   Rare............  Pelagic, shelf,   N.A.............  53,000 \22\....  NL.............  NC.............        0        0
     (Globicephala                                coastal.                                                                                    0        0
     macrorhynchus).                                                                                                                          0        0
    Harbor porpoise (Phocoena  Uncommon........  Coastal.........  11,146 \25\.....  168,387 \27\...  NL.............  NC.............     3.67    46.71
     phocoena).                                                    31,046 \26\.....                                                        2.87    14.43
                                                                                                                                              0        0
    Dall's porpoise            Common..........  Pelagic, shelf..  83,400 \20\.....  1,186,000 \28\.  NL.............  NC.............    13.57    21.77
     (Phocoenoides dalli).                                                                                                                31.56    37.23
                                                                                                                                          25.69    62.50
Pinnipeds:
    Northern fur seal          Uncommon........  Pelagic, breeds   653,171 \7\.....  1.1 million      NL.............  D..............        0        0
     (Callorhinus ursinus).                       coastally.                          \29\.                                                   0        0
                                                                                                                                              0        0
    Steller sea lion           Common..........  Coastal,          58,334-72,223.\3  N.A............  T \36\.........  D..............     3.29     3.99
     (Eumetopias jubatus).                        offshore.         0\                                EN \36\........                      2.91     4.20
                                                                   42,366 \31\.....                                                        9.80    14.70
    California sea lion        Uncommon........  Coastal.........  N.A.............  238,000 \33\...  NL.............  NC.............      N.A      N.A
     (Zalophus c.
     californianus).
    Harbor seal (Phoca         Uncommon........  Coastal.........  45,975 \26\.....  180,017 \32\...  NL.............  NC.............     1.65      2.0
     vitulina richardsi).                                                                                                                 14.03    20.28
                                                                                                                                              0        0
    Northern elephant seal     Uncommon........  Coastal,          N.A.............  124,000 \33\...  NL.............  NC.............        0        0
     (Mirounga                                    offshore.                                                                                   0        0
     angustirostris).                                                                                                                         0        0
--------------------------------------------------------------------------------------------------------------------------------------------------------
N.A. Not available or not assessed.
\1\ U.S. Endangered Species Act: EN = Endangered, T = Threatened, NL = Not listed.
\2\ U.S. Marine Mammal Protection Act: D = Depleted, NC = Not Classified.
\3\ Best density estimate as listed in Table 3 of the application.
\4\ Maximum density estimate as listed in Table 3 of the application.
\5\ Bering Sea and Aleutian Islands (Wade et al., 2010).
\6\ Western population (Brownell et al., 2001).
\7\ Eastern North Pacific (Allen and Angliss, 2010).
\8\ GOA (Calambokidis et al., 2008).
\9\ North Pacific Ocean (Barlow et al., 2009).
\10\ Western GOA and eastern Aleutians (Zerbini et al., 2006).
\11\ Northwest Pacific (Buckland et al., 1992; IWC, 2009).
\12\ North Pacific (Tillman, 1977).
\13\ North Pacific (Ohsumi and Wada, 1974).
\14\ Eastern North Pacific (NMFS, 1998).
\15\ Western GOA and eastern Aleutians (Zerbini et al., 2004).
\16\ Eastern temperate North Pacific (Whitehead, 2002b).
\17\ Eastern Tropical Pacific (Wade and Gerrodette, 1993).
\18\ Western North Pacific (Reeves and Leatherwood, 1994; Kasuya, 2002).
\19\ Cook Inlet stock (Shelden et al., 2010).
\20\ Alaska stock (Allen and Angliss, 2010).
\21\ North Pacific Ocean (Miyashita, 1993b).
\22\ Western North Pacific Ocean (Miyashita, 1993a).
\23\ Minimum abundance in Alaska, includes 2,084 resident and 552 GOA, Bering Sea, Aleutian Islands transients (Allen and Angliss, 2010).
\24\ Eastern Tropical Pacific (Ford, 2002).
\25\ Southeast Alaska stock (Allen and Angliss, 2010).
\26\ GOA stock (Allen and Angliss, 2010).
\27\ Eastern North Pacific (totals from Carretta et al., 2009 and Allen and Angliss, 2010).
\28\ North Pacific Ocean and Bering Sea (Houck and Jefferson, 1999).
\29\ North Pacific (Gelatt and Lowry, 2008).
\30\ Eastern U.S. Stock (Allen and Angliss, 2010).
\31\ Western U.S. Stock (Allen and Angliss, 2010).
\32\Alaska statewide (Allen and Angliss, 2010).
\33\ Caretta et al., 2009.
\34\ Cook Inlet DPS is listed as Endangered and Depleted; other stocks are not listed.
\35\ Stocks in Alaska are not listed, but the southern resident DPS is listed as endangered. AT1 transient in Alaska is considered depleted and a
  strategic stock (NOAA, 2004a).
\36\ Eastern stock is listed as threatened, and the western stock is listed as endangered.

    Refer to Section III and IV of L-DEO's application for detailed 
information regarding the abundance and distribution, population 
status, and life history and behavior of these species and their 
occurrence in the project area. The application also presents how L-DEO 
calculated the estimated densities for the marine mammals in the survey

[[Page 38629]]

area. NMFS has reviewed these data and determined them to be the best 
available scientific information for the purposes of the IHA.

Potential Effects on Marine Mammals

    Acoustic stimuli generated by the operation of the airguns, which 
introduce sound into the marine environment, may have the potential to 
cause Level B harassment of marine mammals in the survey area. The 
effects of sounds from airgun operations might include one or more of 
the following: Tolerance, masking of natural sounds, behavioral 
disturbance, temporary or permanent hearing impairment, or non-auditory 
physical or physiological effects (Richardson et al., 1995; Gordon et 
al., 2004; Nowacek et al., 2007; Southall et al., 2007).
    Permanent hearing impairment, in the unlikely event that it 
occurred, would constitute injury, but temporary threshold shift (TTS) 
is not an injury (Southall et al., 2007). Although the possibility 
cannot be entirely excluded, it is unlikely that the project would 
result in any cases of temporary or permanent hearing impairment, or 
any significant non-auditory physical or physiological effects. Based 
on the available data and studies described here, some behavioral 
disturbance is expected, but NMFS expects the disturbance to be 
localized and short-term.
    The notice of the proposed IHA (76 FR 26255, May 6, 2011) included 
a discussion of the effects of sounds from airguns on mysticetes, 
odontocetes, and pinnipeds including tolerance, masking, behavioral 
disturbance, hearing impairment, and other non-auditory physical 
effects. NMFS refers the reader to L-DEO's application, and EA for 
additional information on the behavioral reactions (or lack thereof) by 
all types of marine mammals to seismic vessels.

Anticipated Effects on Marine Mammal Habitat, Fish, Fisheries, and 
Invertebrates

    NMFS included a detailed discussion of the potential effects of 
this action on marine mammal habitat, including physiological and 
behavioral effects on marine fish, fisheries, and invertebrates in the 
notice of the proposed IHA (76 FR 26255, May 6, 2011). While NMFS 
anticipates that the specified activity may result in marine mammals 
avoiding certain areas due to temporary ensonification, this impact to 
habitat is temporary and reversible which NMFS considered in further 
detail in the notice of the proposed IHA (76 FR 25255, May 6, 2011) as 
behavioral modification. The main impact associated with the activity 
would be temporarily elevated noise levels and the associated direct 
effects on marine mammals.
    Recent work by Andre et al. (2011) purports to present the first 
morphological and ultrastructural evidence of massive acoustic trauma 
(i.e., permanent and substantial alterations of statocyst sensory hair 
cells) in four cephalopod species subjected to low-frequency sound. The 
cephalopods, primarily cuttlefish, were exposed to continuous 40 to 400 
Hz sinusoidal wave sweeps (100% duty cycle and 1 s sweep period) for 
two hours while captive in relatively small tanks (one 2,000 liter [L, 
2 m\3\] and one 200 L [0.2 m\3\] tank). The received SPL was reported 
as 1575 dB re 1 [micro]Pa, with peak levels at 175 dB re 1 
[micro]Pa. As in the McCauley et al. (2003) paper on sensory hair cell 
damage in pink snapper as a result of exposure to seismic sound, the 
cephalopods were subjected to higher sound levels than they would be 
under natural conditions, and they were unable to swim away from the 
sound source.

Mitigation

    In order to issue an ITA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, and other means of effecting the least practicable adverse 
impact on such species or stock and its habitat, paying particular 
attention to rookeries, mating grounds, and areas of similar 
significance, and the availability of such species or stock for taking 
for certain subsistence uses.
    L-DEO has based the mitigation measures described herein, to be 
implemented for the seismic survey, on the following:
    (1) Protocols used during previous L-DEO seismic research cruises 
as approved by NMFS;
    (2) Previous IHA applications and IHAs approved and authorized by 
NMFS; and
    (3) Recommended best practices in Richardson et al. (1995), Pierson 
et al. (1998), and Weir and Dolman (2007).
    To reduce the potential for disturbance from acoustic stimuli 
associated with the activities, L-DEO and/or its designees will 
implement the following mitigation measures for marine mammals:
    (1) EZs;
    (2) Power-down procedures;
    (3) Shut-down procedures;
    (4) Ramp-up procedures; and
    (5) Special procedures for situations and species of concern.
    Planning Phase--The PIs worked with L-DEO and NSF to identify 
potential time periods to carry out the survey taking into 
consideration key factors such as environmental conditions (i.e., the 
seasonal presence of marine mammals, sea turtles, and sea birds), 
weather conditions, and equipment. The survey was previously scheduled 
for September, 2010; however after further consideration, it was viewed 
as not a viable operational option because of the strong possibility of 
not being able to carry out the science mission under potential weather 
conditions in the region at that time of year. Also, the late June to 
early August cruise avoids the peak in humpback abundance (late August 
to early September) and the peak of the marine mammal harvest 
(generally September to December, with a reduction in hunting effort in 
summer).
    Reducing the size of the energy source was also considered, but it 
was decided that the 6,600 in\3\, 36 airgun array is necessary to 
penetrate through the seafloor to accurately delineate the geologic 
features and to achieve the primary scientific objectives of the 
program. A large source that is rich in relatively low-frequency 
seismic energy is required to penetrate to depths greater than 20 to 30 
km (10.8 to 16.2 nmi) and image the deep fault that causes earthquakes 
off Alaska. By towing this source configuration at 12 m below the sea 
surface, the lower frequencies are enhanced. If a smaller source were 
used, it would inhibit the deep imaging of the fault zone, thus 
preventing the scientists' ability to carry out their research and meet 
their objectives. Similarly, the combination of OBSs and hydrophone 
streamers are needed to record seismic returns from deep in the earth 
and determine the depth and geometry of the fault zone, thus meeting 
the scientific objectives.
    EZs--Received sound levels have been determined by corrected 
empirical measurements for the 36 airgun array, and a L-DEO model was 
used to predict the EZs for the single 1900LL 40 in\3\ airgun, which 
will be used during power-downs. Results were recently reported for 
propagation measurements of pulses from the 36 airgun array in two 
water depths (approximately 1,600 m and 50 m [5,249 to 164 ft]) in the 
GOM in 2007 to 2008 (Tolstoy et al., 2009). It would be prudent to use 
the corrected empirical values that resulted to determine EZs for the 
airgun array. Results of the propagation measurements (Tolstoy et al., 
2009) showed that radii around the airguns for various received levels 
varied with water depth. As results for

[[Page 38630]]

measurements in intermediate depth water are still under analysis, 
values halfway between the deep and shallow-water measurements were 
used. In addition, propagation varies with array tow depth. The depth 
of the array was different in the GOM calibration study (6 m [19.7 ft]) 
than in the survey in the GOA (12 m); thus, correction factors have 
been applied to the distances reported by Tolstoy et al. (2009). The 
correction factors used were the ratios of the 160, 180, and 190 dB 
distances from the modeled results for the 6,600 in\3\ airgun array 
towed at 6 m versus 12 m.
    Measurements were not reported for a single airgun, so model 
results will be used. The tow depth has minimal effect on the maximum 
near-field output and the shape of the frequency spectrum for the 
single airgun; thus, the predicted EZ are essentially the same at 
different tow depths. The L-DEO model does not allow for bottom 
interactions, and thus is most directly applicable to deep water and to 
relatively short ranges; correction factors were used to estimate EZs 
in shallow and intermediate depth water as was done for previous L-DEO 
surveys from the Langseth. A detailed description of the modeling 
effort is predicted in Appendix A of the EA.
    Based on the corrected propagation measurements (airgun array) and 
modeling (single airgun), the distances from the source where sound 
levels are predicted to be 190, 180, and 160 dB re 1 [mu]Pa (rms) were 
determined (see Table 2 below). The 180 and 190 dB radii are shut-down 
criteria applicable to cetaceans and pinnipeds, respectively, as 
specified by NMFS (2000); these levels were used to establish the EZs. 
If the PSVO detects marine mammal(s) within or about to enter the 
appropriate EZ, the airguns will be powered-down (or shut-down, if 
necessary) immediately.
    Table 2 summarizes the predicted distances at which sound levels 
(160, 180, and 190 dB [rms]) are expected to be received from the 36 
airgun array and a single airgun operating in deep water depths.

 Table 2--Measured (Array) or Predicted (Single Airgun) Distances to Which Sound Levels >= 190, 180, and 160 dB re: 1 [mu]Pa (RMS) Could Be Received in
                                Various Water Depth Categories During the Survey in the Western GOA, June to August, 2011
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                Predicted RMS radii distances  (m)
            Source and volume                     Tow depth  (m)                Water depth  (m)         -----------------------------------------------
                                                                                                              190 dB          180 dB          160 dB
--------------------------------------------------------------------------------------------------------------------------------------------------------
Single Bolt airgun (40 in\3\)............  6 to 12....................  Deep (>1,000 )..................              12              40             385
                                                                        Intermediate (100 to 1,000).....              18              60             578
                                                                        Shallow (<100)..................             150             296           1,050
4 Strings 36 airguns (6,600 in\3\).......  12.........................  Deep (>1,000)...................             460           1,100           4,400
                                                                        Intermediate (100 to 1,000).....             615           1,810          13,935
                                                                        Shallow (<100)..................             770           2,520          23,470
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Power-down Procedures--A power-down involves decreasing the number 
of airguns in use to one airgun, such that the radius of the 180 dB (or 
190 dB) zone is decreased to the extent that marine mammals are no 
longer in or about to enter the EZ. A power-down of the airgun array 
can also occur when the vessel is moving from one seismic line to 
another. During a power-down for mitigation, L-DEO will operate one 
airgun. The continued operation of one airgun is intended to alert 
marine mammals to the presence of the seismic vessel in the area. In 
contrast, a shut-down occurs when the Langseth suspends all airgun 
activity.
    If the PSVO detects a marine mammal outside the EZ, but it is 
likely to enter the EZ, L-DEO will power-down the airguns before the 
animal is within the EZ. Likewise, if a mammal is already within the 
EZ, when first detected L-DEO will power-down the airguns immediately. 
During a power-down of the airgun array, L-DEO will also operate the 40 
in\3\ airgun. If a marine mammal is detected within or near the smaller 
EZ around that single airgun (Table 1), L-DEO will shut-down the airgun 
(see next section).
    Following a power-down, L-DEO will not resume airgun activity until 
the marine mammal has cleared the EZ. L-DEO will consider the animal to 
have cleared the EZ if:
     A PSVO has visually observed the animal leave the EZ, or
     A PSVO has not sighted the animal within the EZ for 15 min 
for species with shorter dive durations (i.e., small odontocetes or 
pinnipeds), or 30 min for species with longer dive durations (i.e., 
mysticetes and large odontocetes, including sperm, killer, and beaked 
whales).
    During airgun operations following a power-down (or shut-down) 
whose duration has exceeded the time limits specified previously, L-DEO 
will ramp-up the airgun array gradually (see Shut-down and Ramp-up 
Procedures).
    Shut-down Procedures--L-DEO will shut down the operating airgun(s) 
if a marine mammal is seen within or approaching the EZ for the single 
airgun. L-DEO will implement a shut-down:
    (1) If an animal enters the EZ of the single airgun after L-DEO has 
initiated a power-down; or
    (2) If an animal is initially seen within the EZ of the single 
airgun when more than one airgun (typically the full airgun array) is 
operating.
    L-DEO will not resume airgun activity until the marine mammal has 
cleared the EZ, or until the PSVO is confident that the animal has left 
the vicinity of the vessel. Criteria for judging that the animal has 
cleared the EZ will be as described in the preceding section.
    Ramp-up Procedures--L-DEO will follow a ramp-up procedure when the 
airgun array begins operating after a specified period without airgun 
operations or when a power-down has exceeded that period. L-DEO 
proposes that, for the present cruise, this period would be 
approximately nine min. This period is based on the 180 dB radius 
(1,100 m) for the 36 airgun array towed at a depth of 12 m in relation 
to the minimum planned speed of the Langseth while shooting (7.4 km/
hr). L-DEO has used similar periods (approximately 8 to 10 min) during 
previous surveys.
    Ramp-up will begin with the smallest airgun in the array (40 
in\3\). Airguns will be added in a sequence such that the source level 
of the array will increase in steps not exceeding approximately six dB 
per five min period over a total

[[Page 38631]]

duration of approximately 35 min. During ramp-up, the Protected Species 
Observers (PSOs) will monitor the EZ, and if marine mammals are 
sighted, L-DEO will implement a power-down or shut-down as though the 
full airgun array were operational.
    If the complete EZ has not been visible for at least 30 min prior 
to the start of operations in either daylight or nighttime, L-DEO will 
not commence the ramp-up unless at least one airgun (40 in\3\ or 
similar) has been operating during the interruption of seismic survey 
operations. Given these provisions, it is likely that the airgun array 
will not be ramped-up from a complete shut-down at night or in thick 
fog, because the outer part of the EZ for that array will not be 
visible during those conditions. If one airgun has operated during a 
power-down period, ramp-up to full power will be permissible at night 
or in poor visibility, on the assumption that marine mammals will be 
alerted to the approaching seismic vessel by the sounds from the single 
airgun and could move away. L-DEO will not initiate a ramp-up of the 
airguns if a marine mammal is sighted within or near the applicable EZs 
during the day or close to the vessel at night.
    Special Procedures for Situations and Species of Concern--L-DEO 
will implement special mitigation procedures as follows:
     The airguns will be shut down immediately if ESA-listed 
species for which no takes are being requested (i.e., North Pacific 
right, sei, blue, and beluga whales) are sighted at any distance from 
the vessel. Ramp-up will only begin if the whale has not been seen for 
30 min.
     Concentrations of humpback, fin, and/or killer whales will 
be avoided if possible, and the array will be powered down if 
necessary. For purposes of this survey, a concentration or group of 
whales will consist of three or more individuals visually sighted that 
do not appear to be traveling (e.g., feeding, socializing, etc.).
     Seismic operations in Chignik Bay will be conducted from 
nearshore to offshore waters.
     Avoidance of areas where subsistence fishers are fishing, 
if requested (or viewed as necessary).
    NMFS has carefully evaluated the applicant's mitigation measures 
and has considered a 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. NMFS's evaluation of potential measures included 
consideration of the following factors in relation to one another:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure is expected to minimize adverse impacts 
to marine mammals;
    (2) The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned; and
    (3) The practicability of the measure for applicant implementation.
    Based on NMFS's evaluation of the applicant's measures, as well as 
other measures considered by NMFS or recommended by the public, NMFS 
has determined that the mitigation measures provide the means of 
effecting the least practicable adverse impacts on marine mammal 
species or stocks and their habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance.

Monitoring and Reporting

    In order to issue an ITA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth ``requirements pertaining to 
the monitoring and reporting of such taking.'' The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for IHAs 
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.

Monitoring

    L-DEO will sponsor marine mammal monitoring during the present 
project, in order to implement the mitigation measures that require 
real-time monitoring, and to satisfy the monitoring requirements of the 
IHA. L-DEO's Monitoring Plan is described below this section. The 
monitoring work described here has been planned as a self-contained 
project independent of any other related monitoring projects that may 
be occurring simultaneously in the same regions. L-DEO is prepared to 
discuss coordination of its monitoring program with any related work 
that might be done by other groups insofar as this is practical and 
desirable.

Vessel-Based Visual Monitoring

    L-DEO's PSVOs will be based aboard the seismic source vessel and 
will watch for marine mammals near the vessel during daytime airgun 
operations and during any ramp-ups at night. PSVOs will also watch for 
marine mammals near the seismic vessel for at least 30 min prior to the 
start of airgun operations after an extended shut-down (i.e., greater 
than approximately 9 min for this cruise). When feasible, PSVOs will 
conduct observations during daytime periods when the seismic system is 
not operating for comparison of sighting rates and behavior with and 
without airgun operations and between acquisition periods. Based on 
PSVO observations, the airguns will be powered down or shut down when 
marine mammals are observed within or about to enter a designated EZ. 
The EZ is a region in which a possibility exists of adverse effects on 
animal hearing or other physical effects.
    During seismic operations in the western GOA, at least four PSOs 
(PSVO and/or PSAO) will be based aboard the Langseth. L-DEO will 
appoint the PSOs with NMFS's concurrence. Observations will take place 
during ongoing daytime operations and nighttime ramp-ups of the 
airguns. During the majority of seismic operations, two PSVOs will be 
on duty from the observation tower to monitor marine mammals near the 
seismic vessel. Use of two simultaneous PSVOs will increase the 
effectiveness of detecting animals near the source vessel. However, 
during meal times and bathroom breaks, it is sometimes difficult to 
have two PSVOs on effort, but at least one PSVO will be on duty. 
PSVO(s) will be on duty in shifts of duration no longer than 4 hrs.
    Two PSVOs will also be on visual watch during all nighttime ramp-
ups of the seismic airguns. A third PSAO will monitor the PAM equipment 
24 hours a day to detect vocalizing marine mammals present in the 
action area. In summary, a typical daytime cruise would have scheduled 
two PSVOs on duty from the observation tower, and a third PSAO on PAM. 
Other crew will also be instructed to assist in detecting marine 
mammals and implementing mitigation requirements (if practical). Other 
crew will also be instructed to assist in detecting marine mammals and 
implementing mitigation requirements. Before the start of the seismic 
survey, the crew will be given additional instruction on how to do so.
    The Langseth is a suitable platform for marine mammal observations. 
When stationed on the observation platform, the eye level will be 
approximately 21.5 m (70.5 ft) above sea level, and the PSVO will have 
a good view around the entire vessel. During daytime, the PSVOs will 
scan the area around the vessel systematically with reticle binoculars 
(e.g., 7 x 50 Fujinon), Big-eye binoculars (25 x 150), and with the 
naked eye. During darkness, night vision devices (NVDs) will be 
available

[[Page 38632]]

(ITT F500 Series Generation 3 binocular-image intensifier or 
equivalent), when required. Laser range-finding binoculars (Leica LRF 
1200 laser rangefinder or equivalent) will be available to assist with 
distance estimation. Those are useful in training observers to estimate 
distances visually, but are generally not useful in measuring distances 
to animals directly; that is done primarily with the reticles in the 
binoculars.
    When marine mammals are detected within or about to enter the 
designated EZ, the airguns will immediately be powered-down or shut-
down if necessary. The PSVO(s) will continue to maintain watch to 
determine when the animal(s) are outside the EZ by visual confirmation. 
Airgun operations will not resume until the animal is confirmed to have 
left the EZ, or if not observed after 15 min for species with shorter 
dive durations (small odontocetes and pinnipeds) or 30 min for species 
with longer dive durations (mysticetes and large odontocetes, including 
sperm, killer, and beaked whales).

Passive Acoustic Monitoring (PAM)

    PAM will complement the visual monitoring program, when 
practicable. Visual monitoring typically is not effective during 
periods of poor visibility or at night, and even with good visibility, 
is unable to detect marine mammals when they are below the surface or 
beyond visual range. Acoustical monitoring can be used in addition to 
visual observations to improve detection, identification, and 
localization of cetaceans. The acoustic monitoring will serve to alert 
visual observers (if on duty) when vocalizing cetaceans are detected. 
It is only useful when marine mammals call, but it can be effective 
either by day or by night, and does not depend on good visibility. It 
will be monitored in real time so that the PSVOs can be advised when 
cetaceans are detected.
    The PAM system consists of hardware (i.e., hydrophones) and 
software. The ``wet end'' of the system consists of a towed hydrophone 
array that is connected to the vessel by a tow cable. The tow cable is 
250 m (820.2 ft) long, and the hydrophones are fitted in the last 10 m 
(32.8 ft) of cable. A depth gauge is attached to the free end of the 
cable, and the cable is typically towed at depths less than 20 m (65.6 
ft). The array will be deployed from a winch located on the back deck. 
A deck cable will connect from the winch to the main computer 
laboratory where the acoustic station, signal conditioning, and 
processing system will be located. The acoustic signals received by the 
hydrophones are amplified, digitized, and then processed by the 
Pamguard software. The system can detect marine mammal vocalizations at 
frequencies up to 250 kHz.
    One Protected Species Acoustic Observer (PSAO, an expert 
bioacoustician in addition to the four PSVOs), with primary 
responsibility for PAM, will be onboard the Langseth. The towed 
hydrophones will ideally be monitored by the PSAO 24 hours per day 
while at the seismic survey area during airgun operations, and during 
most periods when the Langseth is under way while the airguns are not 
operating. However, PAM may not be possible if damage occurs to the 
array or back-up systems during operations. The primary PAM streamer on 
the Langseth is a digital hydrophone streamer. Should the digital 
streamer fail, back-up systems should include an analog spare streamer 
and a hull-mounted hydrophone. One PSAO will monitor the acoustic 
detection system by listening to the signals from two channels via 
headphones and/or speakers and watching the real-time spectrographic 
display for frequency ranges produced by cetaceans. The PSAO monitoring 
the acoustical data will be on shift for one to six hours at a time. 
All PSOs are expected to rotate through the PAM position, although the 
expert PSAO will be on PAM duty more frequently.
    When a vocalization is detected while visual observations are in 
progress, the PSAO will contact the PSVO immediately, to alert him/her 
to the presence of cetaceans (if they have not already been seen), and 
to allow a power-down or shut-down to be initiated, if required. When 
bearings (primary and mirror-image) to calling cetacean(s) are 
determined, the bearings will be related to the PSVO(s) to help him/her 
sight the calling animal. The information regarding the call will be 
entered into a database. Data entry will include an acoustic encounter 
identification number, whether it was linked with a visual sighting, 
date, time when first and last heard and whenever any additional 
information was recorded, position and water depth when first detected, 
bearing if determinable, species or species group (e.g., unidentified 
dolphin, sperm whale), types and nature of sounds heard (e.g., clicks, 
continuous, sporadic, whistles, creaks, burst pulses, strength of 
signal, etc.), and any other notable information. The acoustic 
detection can also be recorded for further analysis.

PSVO Data and Documentation

    PSVOs will record data to estimate the numbers of marine mammals 
exposed to various received sound levels and to document apparent 
disturbance reactions or lack thereof. Data will be used to estimate 
numbers of animals potentially ``taken'' by harassment (as defined in 
the MMPA). They will also provide information needed to order a power-
down or shut-down of the airguns when a marine mammal is within or near 
the EZ. Observations will also be made during daytime periods when the 
Langseth is under way without seismic operations. In addition to 
transits to, from, and through the study area, there will also be 
opportunities to collect baseline biological data during the deployment 
and recovery of OBSs.
    When a sighting is made, the following information about the 
sighting will be recorded:
    1. Species, group size, age/size/sex categories (if determinable), 
behavior when first sighted and after initial sighting, heading (if 
consistent), bearing and distance from seismic vessel, sighting cue, 
apparent reaction to the airguns or vessel (e.g., none, avoidance, 
approach, paralleling, etc.), and behavioral pace.
    2. Time, location, heading, speed, activity of the vessel, sea 
state, visibility, and sun glare.
    The data listed under (2) will also be recorded at the start and 
end of each observation watch, and during a watch whenever there is a 
change in one or more of the variables.
    All observations and power-downs or shut-downs will be recorded in 
a standardized format. Data will be entered into an electronic 
database. The accuracy of the data entry will be verified by 
computerized data validity checks as the data are entered and by 
subsequent manual checking of the database. These procedures will allow 
initial summaries of data to be prepared during and shortly after the 
field program, and will facilitate transfer of the data to statistical, 
graphical, and other programs for further processing and archiving.
    Results from the vessel-based observations will provide:
    1. The basis for real-time mitigation (airgun power-down or shut-
down).
    2. Information needed to estimate the number of marine mammals 
potentially taken by harassment, which must be reported to NMFS.
    3. Data on the occurrence, distribution, and activities of marine 
mammals in the area where the seismic study is conducted.

[[Page 38633]]

    4. Information to compare the distance and distribution of marine 
mammals relative to the source vessel at times with and without seismic 
activity.
    5. Data on the behavior and movement patterns of marine mammals 
seen at times with and without seismic activity.
    L-DEO will submit a report to NMFS and NSF within 90 days after the 
end of the cruise. The report will describe the operations that were 
conducted and sightings of marine mammals near the operations. The 
report will provide full documentation of methods, results, and 
interpretation pertaining to all monitoring. The 90-day report will 
summarize the dates and locations of seismic operations, and all marine 
mammal sightings (dates, times, locations, activities, associated 
seismic survey activities). The report will also include estimates of 
the number and nature of exposures that could result in ``takes'' of 
marine mammals by harassment or in other ways.
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by this IHA, 
such as an injury (Level A harassment), serious injury or mortality 
(e.g., ship-strike, gear interaction, and/or entanglement), L-DEO will 
immediately cease the specified activities and immediately report the 
incident to the Chief of the Permits, Conservation, and Education 
Division, Office of Protected Resources, NMFS at 301-427-8401 and/or by 
e-mail to [email protected] and [email protected], and the 
Alaska Regional Stranding Coordinators ([email protected] and 
[email protected]). The report must include the following 
information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Name and type of vessel involved;
     Vessel's speed during and leading up to the incident;
     Description of the incident;
     Status of all sound source use in the 24 hours preceding 
the incident;
     Water depth;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).

Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS shall work with L-DEO to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. L-DEO may not resume their 
activities until notified by NMFS via letter or e-mail, or telephone.
    In the event that L-DEO discovers an injured or dead marine mammal, 
and the lead PSO determines that the cause of the injury or death is 
unknown and the death is relatively recent (i.e., in less than a 
moderate state of decomposition as described in the next paragraph), L-
DEO will immediately report the incident to the Chief of the Permits, 
Conservation, and Education Division, Office of Protected Resources, 
NMFS, at 301-427-8401, and/or by e-mail to [email protected] and 
[email protected], and the NMFS Alaska Stranding Hotline (1-
877-925-7773) and/or by e-mail to the Alaska Regional Stranding 
Coordinators ([email protected] and [email protected]). The 
report must include the same information identified in the paragraph 
above. Activities may continue while NMFS reviews the circumstances of 
the incident. NMFS will work with L-DEO to determine whether 
modifications in the activities are appropriate.
    In the event that L-DEO discovers an injured or dead marine mammal, 
and the lead PSO determines that the injury or death is not associated 
with or related to the activities authorized in the IHA (e.g., 
previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), L-DEO will report the incident to 
the Chief of the Permits, Conservation, and Education Division, Office 
of Protected Resources, NMFS, at 301-427-8401, and/or by e-mail to 
[email protected] and [email protected], and the NMFS 
Alaska Stranding Hotline (1-877-925-7773), and/or by e-mail to the 
Alaska Regional Stranding Coordinators ([email protected] and 
[email protected]), within 24 hours of discovery. L-DEO will 
provide photographs or video footage (if available) or other 
documentation of the stranded animal sighting to NMFS and the Marine 
Mammal Stranding Network.

Estimated Take by Incidental Harassment

    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as:

    any act of pursuit, torment, or annoyance which (i) has the 
potential to injure a marine mammal or marine mammal stock in the 
wild [Level A harassment]; or (ii) has the potential to disturb a 
marine mammal or marine mammal stock in the wild by causing 
disruption of behavioral patterns, including, but not limited to, 
migration, breathing, nursing, breeding, feeding, or sheltering 
[Level B harassment].

    Only take by Level B harassment is anticipated and authorized as a 
result of the marine seismic survey in the western GOA. Acoustic 
stimuli (i.e., increased underwater sound) generated during the 
operation of the seismic airgun array may have the potential to cause 
marine mammals in the survey area to be exposed to sounds at or greater 
than 160 dB or cause temporary, short-term changes in behavior. There 
is no evidence that the planned activities could result in injury, 
serious injury, or mortality within the specified geographic area for 
which NMFS has issued the IHA. Take by injury, serious injury, or 
mortality is thus neither anticipated nor authorized. NMFS has 
determined that the required mitigation and monitoring measures will 
minimize any potential risk for injury, serious injury, or mortality.
    The following sections describe L-DEO's methods to estimate take by 
incidental harassment and present the applicant's estimates of the 
numbers of marine mammals that could be affected during the seismic 
program. The estimates are based on a consideration of the number of 
marine mammals that could be disturbed appreciably by operations with 
the 36 airgun array to be used during approximately 2,553 km of survey 
lines in the western GOA.
    L-DEO assumes that, during simultaneous operations of the airgun 
array and the other sources, any marine mammals close enough to be 
affected by the MBES and SBP would already be affected by the airguns. 
However, whether or not the airguns are operating simultaneously with 
the other sources, marine mammals are expected to exhibit no more than 
short-term and inconsequential responses to the MBES and SBP given 
their characteristics (e.g., narrow, downward-directed beam) and other 
considerations described previously. Such reactions are not considered 
to constitute ``taking'' (NMFS, 2001). Therefore, L-DEO provides no 
additional allowance for animals that could be affected by sound 
sources other than airguns.
    There are several sources of systematic data on the numbers and 
distributions of marine mammals in the coastal and nearshore areas of 
the GOA, but there are fewer data for offshore areas. Zerbini et al. 
(2003, 2006, 2007) conducted vessel-based surveys in the northern and 
western GOA from the Kenai Peninsula to the central Aleutian Islands 
during July to August 2001 to

[[Page 38634]]

2003. These surveys included all of the coastal and nearshore areas of 
the current study area. Killer whales were the principal target of the 
surveys, but the abundance and distribution of fin, humpback, and minke 
whales were also reported. Waite (2003) conducted vessel-based surveys 
in the northern and western GOA from Prince William Sound to 
approximately 160[deg] West off the Alaska Peninsula during June 26 to 
July 15, 2003 (Waite, 2003); cetaceans recorded included small 
odontocetes, beaked whales, and mysticetes. The eastern part of the 
surveys by Zerbini et al. were confined to waters less than 1,000 m 
deep with most effort in depths less than 100 m, and all of Waite's 
survey was confined to waters less than 1,000 m deep with most effort 
in depths 100 to 1,000 m.
    Dahlheim et al. (2000) conducted aerial surveys of the nearshore 
waters from Bristol Bay to Dixon Entrance and reported densities for 
harbor porpoises; the southern Alaska Peninsula and Kodiak Island were 
surveyed during July 6 to August 9, 1992. Dahlheim and Towell (1994) 
conducted vessel-based surveys of Pacific white-sided dolphins in the 
inland waterways of Southeast Alaska during April to May, June or July, 
and September to early October of 1991 to 1993. In a report on a 
seismic cruise in southeast Alaska from Dixon Entrance to Kodiak Island 
during August to September, 2004, MacLean and Koski (2005) included 
density estimates of cetaceans and pinnipeds for each of three depth 
ranges (<100 m, 100 to 1,000 m, and >1,000 m) during non-seismic 
periods. Hauser and Holst (2009) reported density estimates during non-
seismic periods for all marine mammals sighted during a September to 
early October seismic cruise in southeast Alaska for each of the same 
three depth ranges as MacLean and Koski (2005). Rone et al. (2010) 
conducted surveys of the nearshore and offshore GOA during April, 2009 
and provided estimates of densities of humpback and fin whales and 
provided maps with sightings of other species.
    Most surveys for pinnipeds in Alaska waters have estimated the 
number of animals at haul-out sites, not in the water (e.g., Loughlin, 
1994; Sease et al., 2001; Withrow and Cesarone, 2002; Sease and York, 
2003). The Department of the Navy (DON, 2009) estimated monthly in-
water densities of several species of pinnipeds in the offshore GOA 
based on shore counts and biological (mostly breeding) information. To 
our knowledge, the only direct information available on at-sea 
densities of pinnipeds in and near the survey area was provided by 
MacLean and Koski (2005) and Hauser and Holst (2009).
    Table 2 (Table 5 of the EA) gives the estimated average (best) and 
maximum densities in each of three depth ranges for each species of 
marine mammals expected to occur in the waters of the central and 
western GOA. L-DEO used the densities reported by MacLean and Koski 
(2005) and Hauser and Holst (2009), and those calculated from effort 
and sightings in Dahlheim and Towell (1994), Waite (2003), and Rone et 
al. (2010) have been corrected for both trackline detection probability 
and availability bias using correction factors from Dahlheim et al. 
(2000) and Barlow and Forney (2007). Trackline detection probability 
bias is associated with diminishing sightability with increasing 
lateral distance from the trackline ([fnof][0]). Availability bias 
refers to the fact that there is less-than-100% probability of sighting 
an animal that is present along the survey trackline [fnof](0), and it 
is measured by g(0).
    Table 2 (Table 5 of the EA) incorporates the densities from the 
aforementioned studies plus those from the following surveys. L-DEO 
included the killer whale and mysticete densities from the easternmost 
blocks (1 to 10) surveyed by Zerbini et al. (2006, 2007), and the 
harbor porpoise densities for the Kodiak and Alaska Peninsula survey 
areas from Table 3 of Dahlheim et al., (2000) and the Pacific white-
sided dolphin data from only the June or July surveys of Dahlheim and 
Towell (1994). Maps of effort and sightings in Waite (2003) and effort 
in Zerbini et al. (2006, 2007) were used to roughly allocate effort and 
sightings or effort between water depths less than 100 m and 100 to 
1,000 m. Offshore effort and maps of sightings in the offshore stratum 
of Rone et al. (2010) were used to calculate densities for water depths 
greater than 1,000 m. Densities of Steller sea lion, northern fur 
seals, and northern elephant seals in water depths greater than 1,000 m 
were taken from DON (2009; Appendix E, Table 5) for July, and those in 
water depths less than 1,000 m are from MacLean and Koski (2005) and 
Hauser and Holst (2009).
    There is some uncertainty about the representativeness of the data 
and the assumptions used in the calculations below for three main 
reasons:
    (1) The timing of most of the survey effort (17,806 km [9,614.5 
nmi]) (i.e., one of the surveys of Dahlheim and Towell [1994] and the 
surveys of Dahlheim et al. (2000), Waite [2003], MacLean and Koski 
(2005), and Zerbini et al. [2006, 2007]) overlaps the timing of the 
survey, but some survey effort (4,693 km [2,534 nmi])--(i.e., two of 
the surveys of Dahlheim and Towell [1994] and the surveys of Rone et 
al. [2010] and Hauser and Holst [2009]), was earlier (April or June) or 
later (September to October) than the July to August survey;
    (2) Surveys by MacLean and Koski (2005), Hauser and Holst (2009), 
and Dahlheim and Towell (1994) were conducted primarily in southeast 
Alaska (east of the study area); and
    (3) Only the McLean and Koski (2005), Hauser and Holst (2009), and 
Rone et al. (2010) surveys included depths greater than 1,000 m, 
whereas approximately 53% of the line-km are in water depths greater 
than 1,000 m. However, the densities are based on a considerable survey 
effort (22,500 km [12,149 nmi], including 17,806 km in months that 
overlap the survey period), and the approach used here is believed to 
be the best available approach.
    Also, to provide some allowance for these uncertainties, ``maximum 
estimates'' as well as ``best estimates'' of the densities present and 
numbers potentially affected have been derived. Best estimates of 
density are effort-weighted mean densities from all previous surveys, 
whereas maximum estimates of density come from the individual survey 
that provided the highest density. For pinnipeds in deep water where 
only one density was available (DON, 2009), that density was used as 
the best estimate and the maximum is 1.5 times the best estimate.
    For one species, the Dall's porpoise, density estimates in the 
original reports are much higher than densities expected during the 
survey, because this porpoise is attracted to vessels. L-DEO estimates 
for Dall's porpoises are from vessel-based surveys without seismic 
activity; they are overestimates possibly by a factor of 5 times, given 
the tendency of this species to approach vessels (Turnock and Quinn, 
1991). Noise from the airgun array during the survey is expected to at 
least reduce and possibly eliminate the tendency of this porpoise to 
approach the vessel. Dall's porpoises are tolerant of small airgun 
sources (MacLean and Koski, 2005) and tolerated higher sound levels 
than other species during a large-array survey (Bain and Williams, 
2006); however, they did respond to that and another large airgun array 
by moving away (Calambokidis and Osmek, 1998; Bain and Williams, 2006). 
Because of the probable overestimates, the best and maximum estimates 
for Dall's porpoises shown in Table 2 (Table 3 of the IHA application) 
are one-quarter of the reported densities. In fact, actual densities 
are probably slightly lower than that.
    L-DEO's estimates of exposures to various sound levels assume that 
the

[[Page 38635]]

surveys will be fully completed including the contingency line; in 
fact, the ensonified areas calculated using the planned number of line-
km have been increased by 25% to accommodate lines that may need to be 
repeated, equipment testing, etc. As is typical during offshore ship 
surveys, inclement weather and equipment malfunctions are likely to 
cause delays and may limit the number of useful line-kilometers of 
seismic operations that can be undertaken. Furthermore, any marine 
mammal sightings within or near the designated EZs will result in the 
power-down or shut-down of seismic operations as a mitigation measure. 
Thus, the following estimates of the numbers of marine mammals 
potentially exposed to sound levels of 160 dB re 1 [mu]Pa (rms) are 
precautionary and probably overestimate the actual numbers of marine 
mammals that might be involved. These estimates also assume that there 
will be no weather, equipment, or mitigation delays, which is highly 
unlikely.
    L-DEO estimated the number of different individuals that may be 
exposed to airgun sounds with received levels greater than or equal to 
160 dB re 1 [mu]Pa (rms) on one or more occasions by considering the 
total marine area that would be within the 160 dB radius around the 
operating airgun array on at least one occasion and the expected 
density of marine mammals. The number of possible exposures (including 
repeated exposures of the same individuals) can be estimated by 
considering the total marine area that would be within the 160 dB 
radius around the operating airguns, including areas of overlap. In the 
survey, the seismic lines are widely spaced in the survey area, so few 
individual marine mammals would be exposed more than once during the 
survey. The area including overlap is only 1.3 times the area excluding 
overlap. Thus, few individual marine mammals would be exposed more than 
once during the survey. Moreover, it is unlikely that a particular 
animal would stay in the area during the entire survey.
    For each depth stratum, the number of different individuals 
potentially exposed to received levels greater than or equal to 160 re 
1 [mu]Pa (rms) was calculated by multiplying:
    (1) The expected species density, either ``mean'' (i.e., best 
estimate) or ``maximum'', times
    (2) The anticipated area to be ensonified to that level during 
airgun operations excluding overlap.
    The area expected to be ensonified was determined by entering the 
planned survey lines into a MapInfo Geographic Information System 
(GIS), using the GIS to identify the relevant areas by ``drawing'' the 
applicable 160 dB isopleth (see Table 1 of the IHA application) around 
each seismic line, and then calculating the total area within the 
isopleths. Areas of overlap (because of lines being closer together 
than the 160 dB radius) were limited and included only once when 
estimating the number of individuals exposed.
    Applying the approach described above, approximately 49,679 km\2\ 
(14,841.1 nmi\2\) (approximately 62,099 km\2\ [18,105.2 nmi\2\] 
including the 25% contingency) would be within the 160 dB isopleth on 
one or more occasions during the survey. For less than 100 m depth, the 
areas would be 32,451 km\2\ (9,487.4 nmi\2\) (40,564 km\2\ [11,826.6 
nmi\2\] including the 25% contingency). For 100 to 1,000 m, the areas 
would be 8,612 km\2\ (2,510.9 nmi\2\) (10,765 km\2\ [3,138.6 nmi\2\] 
including the 25% contingency). For greater than 1,000 m depth, the 
areas would be 8,616 km\2\ (2,512 nmi\2\) (10,770 km\2\ [3,140 nmi\2\] 
including the 25% contingency). Because this approach does not allow 
for turnover in the marine mammal populations in the study area during 
the course of the survey, the actual number of individuals exposed 
could be underestimated in some cases. However, the conservative (i.e., 
probably overestimated) densities used to calculate the numbers exposed 
may offset this. In addition, the approach assumes that no cetaceans 
will move away from or toward the trackline as the Langseth approaches 
in response to increasing sound levels prior to the time the levels 
reach 160 dB, which will result in overestimates for those species 
known to avoid seismic vessels.
    Table 3 (Table 4 of the IHA application) shows the best and maximum 
estimates of the number of different individual marine mammals that 
potentially could be exposed to greater than or equal to 160 dB re 1 
[mu]Pa (rms) during the seismic survey if no animals moved away from 
the survey vessel. The requested take authorization, given in Table 3 
(the far right column of Table 4 of the IHA application), is based on 
the best estimates rather than the maximum estimates of the numbers 
exposed, because there was little uncertainty associated with the 
method of estimating densities. For cetacean species not listed under 
the ESA that could occur in the study area but were not sighted in the 
surveys from which density estimates were calculated--gray whale 
(<0.1%), Risso's dolphin (<0.1%), short-finned pilot whale (NA), and 
Stejneger's beaked whale (NA)--the average group size has been used to 
request take authorization. For ESA-listed cetacean species unlikely to 
be encountered during the study (North Pacific right, sei, blue, and 
beluga whales), the requested takes are zero.
    The ``best estimate'' of the number of individual cetaceans that 
could be exposed to seismic sounds with received levels greater than or 
equal to 160 dB re 1 [mu]Pa (rms) during the survey is 4,392 (see Table 
4 of the IHA application) for all three depth ranges combined. That 
total includes 1,824 humpback whales, 60 minke whales, 598 fin whales, 
5 sperm whales, 12 Cuvier's beaked whales, 4 Baird's beaked whales, 127 
Pacific white-sided dolphins, 415 killer whales, and180 harbor 
porpoises which would represent 8.8%, 0.2%, 3.7%, 0.1%, 0.1%, 0.1%, 
0.1%, 4.9%, and 0.1% of the regional populations, respectively. After 
humpback whales, Dall's porpoises are expected to be the most common 
species in the study area; the best estimate of the number of Dall's 
porpoises that could be exposed is 1,167 or about 0.1% of the regional 
population. This may be a slight overestimate because the estimated 
densities are slight overestimates. Estimates for other species are 
lower. The ``maximum estimates'' total 12,625 cetaceans for the three 
depth ranges combined.
    ``Best estimates'' of 270 Steller sea lions and 218 harbor seals 
could be exposed to airgun sounds with received levels greater than or 
equal to 160 dB re 1 [mu]Pa (rms). These estimates represent 0.3% of 
the Steller sea lion regional population and less than 0.1% of the 
harbor seal regional population. The estimated numbers of pinnipeds 
that could be exposed to received levels greater than or equal to 160 
dB re 1 [mu]Pa (rms) are probably overestimates of the actual numbers 
that will be affected. Northern fur seals and northern elephant seals 
are at their rookeries in August. No take has been requested for North 
Pacific right, sei, and blue whales, beluga whales, Northern elephant 
seals, Northern fur seals, or California sea lions because they are 
unlikely to be encountered in the study area.

[[Page 38636]]



Table 3--Estimates of the Possible Numbers of Marine Mammals Exposed to Different Sound Levels >=160 dB During L-
                       DEO's Seismic Survey in the Western GOA During June to August, 2011
----------------------------------------------------------------------------------------------------------------
                                          Estimated number  Estimated number
                                           of individuals    of individuals                        Approximate
                                          exposed to sound  exposed to sound                       percent of
                 Species                  levels >= 160 dB  levels >= 160 dB   Take authorized      regional
                                             re 1 [mu]Pa       re 1  [mu]Pa                      population \2\
                                             (best \1\)       (maximum \1\)                          (best)
----------------------------------------------------------------------------------------------------------------
Mysticetes:
    North Pacific right whale...........                 0                 0                 1               0.5
    Gray whale..........................                 0                 0             \3\ 6              <0.1
    Humpback whale......................             1,824             3,458             1,824               8.8
    Minke whale.........................                60               308                60               0.2
    Sei whale...........................                 0                 0                 1              <0.1
    Fin whale...........................               598             2,166               598               3.7
    Blue whale..........................                 0                 0                 1              <0.1
Odontocetes:
    Sperm whale.........................                 5                21                 5              <0.1
    Cuvier's beaked whale...............                12                19                12               0.1
    Baird's beaked whale................                 4                 6                 4               0.1
    Stejneger's beaked whale............                 0                 0            \3\ 15                NA
    Beluga whale........................                 0                 0                 0                 0
    Pacific white-sided dolphin.........               127               348               127              <0.1
    Risso's dolphin.....................                 0                 0            \3\ 33              <0.1
    Killer whale........................               415             2,292               415               4.9
    Short-finned pilot whale............                 0                 0            \3\ 50                NA
    Harbor porpoise.....................               180             2,050               180               0.1
    Dall's porpoise.....................             1,167             1,957             1,167               0.1
Pinnipeds:
    Northern fur seal...................                 0                 0                 0                 0
    Steller sea lion....................               270               365               270               0.3
    California sea lion.................                NA                NA                 0                NA
    Harbor seal.........................               218               299               218               0.1
    Northern elephant seal..............                 0                 0                 0                 0
----------------------------------------------------------------------------------------------------------------
\1\ Best and maximum estimates are based on densities from Table 1 (Table 4 of the IHA application) and
  ensonified areas (including 25% contingency) for 160 dB of 40,564 km\2\, 10,765 km\2\, and 10,770 km\2\ for
  <100 m, 100 to 1,000 m, and >1,000 m depth ranges, respectively.
\2\ Regional population size estimates are from Table 1 (see Table 2 of the IHA application); NA means not
  available.
\3\ Requested takes for species not sighted in surveys from which densities were derived are based on group
  size.

Encouraging and Coordinating Research

    L-DEO and NSF will coordinate the planned marine mammal monitoring 
program associated with the seismic survey in the western GOA with 
other parties that may have an interest in the area and/or be 
conducting marine mammal studies in the same region during the seismic 
survey. L-DEO and NSF will coordinate with applicable U.S. Federal, 
State, and Borough agencies, and will comply with their requirements. 
Actions of this type that are underway include (but are not limited to) 
the following:
     Coordination with the Alaska Department of Fish and Game 
concerning fisheries issues in state waters.
     Contact Alaska Native Harbor Seal Commission, the Aleut 
Marine Mammal Commission, and the Alaska Sea Otter and Steller Sea Lion 
Commission with regard to potential concerns about interactions with 
fisheries and subsistence hunting.
     Contact USFWS regarding concerns about possible impacts on 
sea otters and critical habitat (for ESA).
     Contact USFWS avian biologists (Kathy Kuletz and Tim 
Bowman) regarding potential interaction with seabirds (for ESA).
     Contact Mike Holley, U.S. Army Corps of Engineers (ACOE), 
to confirm that no permits will be required by the ACOE for the survey.
     A Coastal Project Questionnaire and Certification 
statement will be submitted with a copy of the EA to the State of 
Alaska to confirm that the project is in compliance with state and 
local Coastal Management Programs.
     Contact the National Weather Service (NWS; Jack Endicott) 
about the survey with regard to the location of NWS buoys in the survey 
area and the tracklines.
     Contact the logistics coordinator of the local commercial 
fish processor, to ensure that there will be minimal interference with 
the local salmon fishery.

Negligible Impact and Small Numbers Analysis and 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 evaluated factors such as:
    (1) The number of anticipated injuries, serious injuries, or 
mortalities;
    (2) The number, nature, intensity, and duration of Level B 
harassment (all relatively limited);
    (3) The context in which the takes occur (i.e., impacts to areas of 
significance, impacts to local populations, and cumulative impacts when 
taking into account successive/contemporaneous actions when added to 
baseline data);
    (4) The status of stock or species of marine mammals (i.e., 
depleted, not depleted, decreasing, increasing, stable,

[[Page 38637]]

and impact relative to the size of the population);
    (5) Impacts on habitat affecting rates of recruitment or survival; 
and
    (6) The effectiveness of monitoring and mitigation measures (i.e., 
the manner and degree in which the measure is likely to reduce adverse 
impacts to marine mammals, the likely effectiveness of the measures, 
and the practicability of implementation).
    For reasons stated previously in this document, and in the proposed 
notice of an IHA (76 FR 26255, May 6, 2011), the specified activities 
associated with the marine seismic survey are not likely to cause PTS, 
or other non-auditory injury, serious injury, or death because:
    (1) The likelihood that, given sufficient notice through relatively 
slow ship speed, marine mammals are expected to move away from a noise 
source that is annoying prior to its becoming potentially injurious;
    (2) The potential for temporary or permanent hearing impairment is 
relatively low and would likely be avoided through the incorporation of 
the required monitoring and mitigation measures (described above);
    (3) The fact that pinnipeds would have to closer than 460 m 
(1,509.2 ft) in deep water, 615 m (2,017.7 ft) in intermediate water, 
and 770 m (2,526.3 ft) in shallow water when the 36 airgun array and 12 
m (39.4 ft) in deep water, 18 m (59.1 ft) in intermediate water, and 
150 m (492.1 ft) in shallow water when the single airgun is in use at 6 
to 12 m (19.7 to 39.4 ft) tow depth from the vessel to be exposed to 
levels of sound believed to have even a minimal chance of causing PTS;
    (4) The fact that cetaceans would have to be closer than 1,100 m 
(3,608.9 ft) in deep water, 1,810 m (5,938.3 ft) in intermediate water, 
and 2,520 m (8,267.7 ft) in shallow water when the 36 airgun array is 
in use at 12 m tow depth, and 40 m (131.2 ft) in deep water, 60 m 
(196.9 ft) in intermediate water, and 296 m (971.1 ft) in shallow water 
when the single airgun is in use at 6 to 12 m tow depth from the vessel 
to be exposed to levels of sound believed to have even a minimal chance 
of causing PTS; and
    (5) The likelihood that marine mammal detection ability by trained 
PSOs is high at close proximity to the vessel.
    No injuries, serious injuries, or mortalities are anticipated to 
occur as a result of L-DEO's planned marine seismic survey, and none 
are authorized by NMFS. Only short-term, behavioral disturbance is 
anticipated to occur due to the brief and sporadic duration of the 
survey activities. Table 3 in this document outlines the number of 
Level B harassment takes that are anticipated as a result of the 
activities. Due to the nature, degree, and context of Level B 
(behavioral) harassment anticipated and described (see Potential 
Effects on Marine Mammals section above) in this notice, the activity 
is not expected to impact rates of recruitment or survival for any 
affected species or stock.
    Many animals perform vital functions, such as feeding, resting, 
traveling, and socializing, on a diel cycle (i.e., 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). While seismic 
operations are anticipated to occur on consecutive days, the entire 
duration of the survey is not expected to last more than 37 days and 
the Langseth will be continuously moving along planned tracklines. 
Seismic operations in the study area will be carried out for 
approximately 16 days. Therefore, the seismic survey will be increasing 
sound levels in the marine environment surrounding the vessel for 
several weeks in the study area. Of the 23 marine mammal species under 
NMFS jurisdiction that are known to or likely to occur in the study 
area, eight are listed as threatened or endangered under the ESA: North 
Pacific right, humpback, sei, fin, blue, sperm, and Cook Inlet DPS 
beluga whales, and Steller sea lions. These species are also considered 
depleted under the MMPA. The affected humpback whale and Eastern stock 
of Steller sea lion populations have been increasing in recent years. 
There is generally insufficient data to determine population trends for 
the other depleted species in the study area. To protect these animals 
(and other marine mammals in the study area), L-DEO must cease or 
reduce airgun operations if animals enter designated zones. If a North 
Pacific right, sei, blue, and/or beluga whale is visually sighted, the 
airgun array will be shut-down regardless of the distance of the 
animal(s) to the sound source. The airgun array will not resume firing 
after the last documented whale visual sighting. Concentrations of 
humpback, fin, and/or killer whales will be avoided, if possible, and 
the array will be powered-down if necessary. For purposes of this IHA, 
a concentration or group of whales will consist of when three or more 
individuals are visually sighted that do not appear to be traveling 
(e.g., feeding, socializing, etc.). No injury, serious injury, or 
mortality 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.
    As mentioned previously, NMFS estimates that 19 species of marine 
mammals under its jurisdiction could be potentially affected by Level B 
harassment over the course of the IHA. For each species, these numbers 
are small (each, one percent or less, except for humpback [8.8%], fin 
[3.7%], and killer [4.9%] whales) relative to the regional population 
size. The population estimates for the marine mammal species that may 
be taken by harassment, were provided in Table 1 of this document.
    NMFS's practice has been to apply the 160 dB re 1 [micro]Pa (rms) 
received level threshold for underwater impulse sound levels to 
determine whether take by Level B harassment occurs. Southall et al. 
(2007) provide a severity scale for ranking observed behavioral 
responses of both free-ranging marine mammals and laboratory subjects 
to various types of anthropogenic sound (see Table 4 in Southall et al. 
[2007]).
    NMFS has determined, provided that the aforementioned mitigation 
and monitoring measures are implemented, that the impact of conducting 
a marine geophysical survey in the western GOA, June to August, 2011, 
may result, at worst, in a temporary modification in behavior and/or 
low-level physiological effects (Level B harassment) of small numbers 
of certain species of marine mammals. See Table 3 (above) for the 
authorized take numbers of cetaceans and pinnipeds.
    While behavioral modifications, including temporarily vacating the 
area during the operation of the airgun(s), may be made by these 
species to avoid the resultant acoustic disturbance, the availability 
of alternate areas within these areas and the short and sporadic 
duration of the research activities, have led NMFS to determine that 
this action will have a negligible impact on the species in the 
specified geographic region.
    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 L-DEO's planned research activities, will 
result in the incidental take of small numbers of marine mammals, by 
Level B harassment only, and that the total taking from the marine 
seismic survey

[[Page 38638]]

will have a negligible impact on the affected species or stocks of 
marine mammals; and that impacts to affected species or stocks of 
marine mammals have been mitigated to the lowest level practicable.

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

    Marine mammals are hunted legally in Alaska waters by coastal 
Alaska Natives. In the GOA, the marine mammals under NMFS jurisdiction 
that are hunted are Steller sea lions and harbor seals. In 2007, a 
total of 1,428 harbor seals were taken by Alaska Natives (Wolfe et al., 
2009); 654 were taken from the southeast Alaska stock, 686 were taken 
from the GOA stock, and 88 were taken from the Bering Sea stock (Allen 
and Angliss, 2010). In 2008, 1,462 harbor seals were taken by Alaska 
Natives (Wolfe et al., 2009). Most harbor seals were taken by 
communities in southeast Alaska (594), the North Pacific rim (277), 
Kodiak Island (192), and the South Alaska Peninsula (125; Wolfe et al., 
2009). The seasonal distribution of harbor seal takes by Alaska Natives 
typically shows two distinct hunting peaks--one during spring and one 
during all and early winter; however, this pattern was hardly 
noticeable in 2008 (Wolfe et al., 2009). In general the months of 
highest harvest are September through December, with a smaller peak in 
March. Harvests are traditionally low from May through August, when 
harbor seals are raising pups and molting.
    In 2007, a total of 217 Steller sea lions were taken by Alaska 
Natives, excluding St. Paul Island (Wolfe et al., 2009); 211 were from 
the western stock and 6 were from the eastern stock (Allen and Angliss, 
2010). In 2008, 146 sea lions were taken by Alaska Natives (Wolfe et 
al., 2009). Most sea lions were taken by communities in the Aleutian 
Islands (48) and the Pribilof Islands (36); 25 were taken in the North 
Pacific Rim, 19 in the Kodiak Island region, 10 in southeast Alaska, 
and 9 along the South Alaska Peninsula (Wolfe et al., 2009).
    The project could potentially impact the availability of marine 
mammals for harvest in a very small area immediately around the 
Langseth, and for a very short time period during seismic activities. 
Considering the limited time and locations for the planned seismic 
survey, the project is not expected to have any significant impacts to 
the availability of Steller sea lions and harbor seals for subsistence 
harvest.
    Section 101(a)(5)(D) also requires NMFS to determine that the 
authorization will not have an unmitigable adverse effect on the 
availability of marine mammal species or stocks for subsistence use. 
Based on the information above, subsistence uses of marine mammals in 
the study area (waters of the western GOA) that implicate MMPA section 
101(a)(5)(D) are not expected to be impacted.

Endangered Species Act

    Of the species of marine mammals that may occur in the survey area, 
several are listed as endangered under the ESA, including the North 
Pacific right, humpback, sei, fin, blue, and sperm whales, as well as 
the Cook Inlet DPS of beluga whales and the western stock of Steller 
sea lions. The eastern stock of Steller sea lions is listed as 
threatened. Critical habitat for the North Pacific right whale and 
Steller sea lion is also found within the GOA. Under section 7 of the 
ESA, NSF has initiated formal consultation with the NMFS, Office of 
Protected Resources, Endangered Species Division, on this seismic 
survey. NMFS's Office of Protected Resources, Permits, Conservation and 
Education Division, has initiated formal consultation under section 7 
of the ESA with NMFS's Office of Protected Resources, Endangered 
Species Division, to obtain a Biological Opinion (BiOp) evaluating the 
effects of issuing the IHA on threatened and endangered marine mammals 
and, if appropriate, authorizing incidental take. In June 2011, NMFS 
issued a BiOp and concluded that the action and issuance of the IHA are 
not likely to jeopardize the continued existence of North Pacific 
right, humpback, sei, fin, blue, and sperm whales, Cook Inlet DPS of 
beluga whales, and Steller sea lions. The BiOp also concluded that 
designated critical habitat for these species would not be affected by 
the survey. NSF and L-DEO must comply with the Relevant Terms and 
Conditions of the Incidental Take Statement (ITS) corresponding to 
NMFS's BiOp issued to NSF, L-DEO, and NMFS's Office of Protected 
Resources. L-DEO must also comply with the mitigation and monitoring 
requirements included in the IHA in order to be exempt under the ITS in 
the BiOp from the prohibition on take of listed endangered marine 
mammal species otherwise prohibited by section 9 of the ESA.

National Environmental Policy Act (NEPA)

    To meet NMFS's NEPA (42 U.S.C. 4321 et seq.) requirements for the 
issuance of an IHA to L-DEO, NSF prepared an ``Environmental Assessment 
on a Marine Seismic Survey in the Gulf of Alaska, July-August 2011,'' 
which incorporated an ``Environmental Assessment of a Marine 
Geophysical Survey by the R/V Marcus G. Langseth in the western Gulf of 
Alaska, July-August 2011,'' prepared by LGL. NMFS conducted an 
independent review and evaluation of the document for sufficiency and 
compliance with the Council on Environmental Quality regulations and 
NOAA Administrative Order (NAO) 216-6 Sec.  5.09(d) and determined that 
issuance of the IHA is not likely to result in significant impacts on 
the human environment. Consequently, NMFS has adopted NSF's EA and 
prepared a Finding of No Significant Impact (FONSI) for the issuance of 
the IHA. An Environmental Impact Statement is not required and will not 
be prepared for the action.

Authorization

    NMFS has issued an IHA to L-DEO for the take, by Level B 
harassment, of small numbers of marine mammals incidental to conducting 
a marine geophysical survey in the western GOA, June to August, 2011, 
provided the previously mentioned mitigation, monitoring, and reporting 
requirements are incorporated.

    Dated: June 24, 2011.
James H. Lecky,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2011-16606 Filed 6-30-11; 8:45 am]
BILLING CODE 3510-22-P