Takes of Marine Mammals Incidental to Specified Activities; Marine Geophysical Survey in the Western Gulf of Alaska, June to August, 2011, 38621-38638 [2011-16606]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 76, Number 127 (Friday, July 1, 2011)]
[Notices]
[Pages 38621-38638]
From the Federal Register Online via the Government Printing 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: https://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: https://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: https://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 
https://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: https://www.lgl.com/index.php?option=com_content&view=article&id=69&Itemid=162&lang=en. Post-cruise monitoring 
reports are currently available on the NMFS's MMPA Incidental Take 
Program Web site on the NSF Web site (https://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 Michael.Payne@noaa.gov and 
Howard.Goldstein@noaa.gov, and the Alaska Regional Stranding 
Coordinators (Aleria.Jensen@noaa.gov and Barbara.Mahoney@noaa.gov). 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 Michael.Payne@noaa.gov and 
Howard.Goldstein@noaa.gov, and the NMFS Alaska Stranding Hotline (1-
877-925-7773) and/or by e-mail to the Alaska Regional Stranding 
Coordinators (Aleria.Jensen@noaa.gov and Barbara.Mahoney@noaa.gov). 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 Michael.Payne@noaa.gov and 
Howard.Goldstein@noaa.gov, and the NMFS Alaska Stranding Hotline (1-
877-925-7773), and/or by e-mail to the Alaska Regional Stranding 
Coordinators (Aleria.Jensen@noaa.gov and Barbara.Mahoney@noaa.gov), 
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 s