Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Seismic Survey in Cook Inlet, AK, 12720-12744 [2013-04202]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 78, Number 37 (Monday, February 25, 2013)]
[Notices]
[Pages 12720-12744]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-04202]



[[Page 12720]]

-----------------------------------------------------------------------

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XC374


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Seismic Survey in Cook Inlet, AK

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

ACTION: Notice; issuance of incidental take authorization.

-----------------------------------------------------------------------

SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA) 
regulations, notification is hereby given that NMFS has issued an 
Incidental Harassment Authorization (IHA) to the Apache Alaska 
Corporation (Apache) to take marine mammals, by harassment, incidental 
to a proposed 3D seismic survey in Cook Inlet, Alaska, between March 
2013 and March 2014.

DATES: Effective March 1, 2013, to March, 1, 2014.

ADDRESSES: An electronic copy of the IHA and application may be 
obtained by writing P. Michael Payne, Chief, Permits and Conservation 
Division, Office of Protected Resources, National Marine Fisheries 
Service, 1315 East-West Highway, Silver Spring, MD 20910 or by 
telephoning the contact listed below (see FOR FURTHER INFORMATION 
CONTACT), or visiting the Internet at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm. Documents cited in this notice may also be 
viewed, by appointment, during regular business hours, at the 
aforementioned address.

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

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization is 
provided to the public for review.
    Authorization for incidental 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 process by which 
citizens of the U.S. can apply for an authorization to incidentally 
take small numbers of marine mammals by harassment. Section 
101(a)(5)(D) establishes a 45-day time limit for NMFS review of an 
application followed by a 30-day public notice and comment period on 
any proposed authorizations for the incidental harassment of marine 
mammals. Within 45 days of the close of the comment period, NMFS must 
either issue or deny the authorization.
    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].''

Summary of Request

    NMFS received an application on June 15, 2012, from Apache for the 
taking, by harassment, of marine mammals incidental to a 3D seismic 
survey program in Cook Inlet, Alaska. This is the second IHA 
application NMFS has received from Apache for takes of marine mammals 
incidental to conducting a seismic survey in Cook Inlet. On April 30, 
2012, NMFS issued a one-year IHA to Apache for their first season of 
seismic acquisition in Cook Inlet (77 FR 27720). On December 10, 2012, 
NMFS published a notice in the Federal Register (77 FR 73434) 
discussing the effects on marine mammals and making preliminary 
determinations regarding a proposed IHA. The notice initiated a 30 day 
public comment period, which closed on January 9, 2013. Except for the 
location and the size of the survey area and the potentially earlier 
commencement date for survey operations, the activities proposed for 
the second survey season are essentially the same as those conducted 
during the first season.
    Apache's 3D seismic surveys would employ the use of two source 
vessels. Each source vessel would be equipped with compressors and 2400 
in\3\ air gun arrays, as well as additional lower-powered and higher 
frequency survey equipment for collecting bathymetric and shallow sub-
bottom data. In addition, one source vessel would be equipped with a 
440 in\3\ shallow water air gun array, which it can deploy at high tide 
in the intertidal area in less than 1.8 m of water. The proposed survey 
would take place in Cook Inlet. During the 2013 survey season, Apache 
anticipates acquiring seismic data in an area that extends from just 
south of Anchor Point along the east coast extending up to Point 
Possession and along the west coast from the McArthur River up to south 
of the Beluga river, in water depths of 0-128 m (0-420 ft). Apache's 
planned area of seismic acquisition within this area is shown in Figure 
1 below.
    For the 2013 survey season, Apache intends to mobilize crews and 
equipment in February 2013 in order to be ready to conduct marine 
surveys between April and May 2013. Apache expects to complete its 
survey by December 15, 2013. Impacts to marine mammals may occur from 
noise produced from active acoustic sources (primarily air guns) used 
in the survey.

Description of the Specified Activity

    In 2010, Apache acquired over 300,000 acres of oil and gas leases 
in Cook Inlet with the primary objective to explore for and develop oil 
fields. In the spring of 2011, Apache conducted a seismic test program 
to evaluate the feasibility of using new nodal (i.e., no cables) 
technology seismic recording equipment for operations in the Cook Inlet 
environment and to test various seismic acquisition parameters to 
finalize the design for a 3D seismic program in Cook Inlet. The test 
program took place in late March 2011 and results indicated that the 
nodal technology was feasible in the Cook Inlet environment. Apache 
proposes to conduct a phased 3D seismic survey program throughout Cook 
Inlet over the course of three to five years. The first area surveyed--
and the subject of the IHA issued in April 2012--was located in mid-
Cook Inlet extending along the

[[Page 12721]]

west coast from the Big River up to south of the Beluga River, and on 
the east coast from Salamantof on the Kenai peninsula to 4.4 miles 
north of the Swanson River. In the notice of the proposed IHA (77 FR 
73434, December 10, 2012), NMFS described the second area to be 
surveyed--and the subject of this IHA--as covering a lower portion of 
Cook Inlet, but also including all of Area 1. Following the publication 
of the proposed IHA, Apache clarified to NMFS that Area 2 includes all 
of Area 1 in mid Cook Inlet and some of Area 3 to the north/northeast 
of Area 1; however, survey operations in 2013 are expected to occur in 
a smaller section of Area 2 (see Figure 1).
    The survey operations are essentially the same as those that were 
conducted in Area 1 under the IHA for the first seismic season. The 
survey would again be conducted from multiple vessels. Apache employs 
the use of two source vessels. Each source vessel is equipped with 
compressors and 2400 in\3\ air gun arrays. In addition, one source 
vessel is equipped with a 440 in\3\ shallow water air gun array, which 
it can deploy at high tide in the intertidal area in less than 1.8 m of 
water. Three shallow draft vessels support cable/nodal deployment and 
retrieval operations, and one mitigation/chase vessel is used, which 
also provides berthing for the Protected Species Observers (PSOs). 
Finally, two smaller jet boats are used for personnel transport and 
node support in the extremely shallow water of the intertidal area. For 
additional information, such as vessel specifications, see Apache's 
application.
    The survey will take approximately 160 days to complete over the 
course of 8-9 months. Apache anticipates conducting survey operations 
24 hours per day. During each 24 hour period, seismic operations would 
be active; however air guns would only be used for approximately 2.5 
hours during each of the slack tide periods. There are approximately 
four slack tide periods in a 24-hour day, therefore, air gun operations 
would be active during approximately 10-12 hours per day, if weather 
conditions allow.
    NMFS outlined the description of the specified activities covered 
by this IHA in a previous notice for the proposed IHA (77 FR 73434, 
December 10, 2012). Except for the clarification noted above regarding 
the size and scope of Area 2 and the timing of the survey, 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 activity, including vessel and 
acoustic source specifications, the reader should refer to the proposed 
IHA notice (77 FR 73434, December 10, 2012), the IHA application, and 
associated documents (see ADDRESSES).

Comments and Responses

    A notice of receipt of the Apache application and proposed IHA was 
published in the Federal Register on December 10, 2012 (77 FR 73434). 
During the 30-day public comment period, NMFS received comments from 
the Marine Mammal Commission (Commission), the Alaska Department of 
Natural Resources, environmental non-governmental organizations (NGOs), 
the International Association of Geophysical Contractors (IAGC), the 
Seldovia Village Tribe, the Kenaitze Indian Tribe, and one member of 
the public. Following are their comments and NMFS's responses:
    Comment 1: The Commission recommended that NMFS refrain from taking 
additional action on the IHA until it has received and reviewed more 
specific information concerning the location and timing of Apache's 
proposed action.
    Response: We believe that Apache's application requesting 
authorization to harass marine mammals incidental to seismic survey 
operations in Cook Inlet contained sufficient information regarding the 
location and timing of Apache's seismic survey to make the required 
findings under the MMPA.
    Comment 2: The Commission recommended that NMFS require that Apache 
not conduct seismic activities in the inlet until after May and use 
aerial surveys or other means to confirm that the majority of beluga 
whales have moved out of the proposed survey area before initiating 
those activities.
    Response: Beluga whales remain in Cook Inlet year-round, but 
demonstrate seasonal movement within the Inlet; in the summer and fall, 
they concentrate in upper Cook Inlet's rivers and bays, but tend to 
disperse offshore and move to mid-Inlet in winter (Hobbs et al., 2005). 
The available information indicates that in the winter months belugas 
occur in deeper waters in mid-Inlet past Kalgin Island, with occasional 
forays into the upper inlet, including the upper ends of Knik and 
Turnagain Arms. The spatial dispersal and diversity of winter prey are 
likely to influence the wider beluga winter range throughout the mid-
Inlet. Apache now expects to commence its seismic survey in April, 
which would coincide with the time of year when belugas are dispersed 
offshore in the mid-Inlet and away from river mouths. In the spring, 
beluga whales are regularly sighted in the upper Inlet beginning in 
late April or early May, coinciding with eulachon runs in the Susitna 
River and Twenty Mile River in Turnagain Arm, and outside of the area 
where Apache will be conducting seismic surveys at that time. 
Therefore, NMFS believes that the timing and location for the 
commencement of the seismic survey, as proposed, will largely avoid 
areas and seasons that overlap with important beluga whale behavioral 
patterns.
    Comment 3: The Commission recommended that NMFS explain how we 
accounted for the effects of the proposed action in the context of all 
the other risk factors that are or may be affecting Cook Inlet beluga 
whales and inhibiting their recovery.
    Response: Section 101(a)(5)(D) of the MMPA requires NMFS to make a 
determination that the harassment incidental to a specified activity 
will have a negligible impact on the affected species or stocks of 
marine mammals, and will not result in an unmitigable adverse impact on 
the availability of marine mammals for taking for subsistence uses. 
Neither the MMPA nor NMFS' implementing regulations specify how to 
consider other activities and their impacts on the same populations. 
However, consistent with the 1989 preamble for NMFS' implementing 
regulations (54 FR 40338, September 29, 1989), the impacts from other 
past and ongoing anthropogenic activities are incorporated into the 
negligible impact analysis via their impacts on the environmental 
baseline (e.g., as reflected in the density/distribution and status of 
the species, population size and growth rate, and ambient noise).
    In addition, cumulative effects were addressed in the Environmental 
Assessment and biological opinion prepared for this action, both of 
which NMFS indicated would be completed prior to the issuance of an IHA 
(77 FR 73434, December 10, 2012). These documents, as well as the 
Alaska Marine Stock Assessments and the most recent abundance estimate 
for Cook Inlet beluga whales (Shelden et al., 2012), are part of NMFS' 
Administrative Record for this action, and provided the decision maker 
with information regarding other activities in the action area that 
affect marine mammals, an analysis of cumulative impacts, and other 
information relevant to the determination made under the MMPA.
    Comment 4: The Commission recommended that NMFS encourage Apache to 
use and expand data-sharing agreements with other entities to maximize 
the utility of seismic data and

[[Page 12722]]

minimize the number of impacts of new seismic studies.
    Response: We agree and have encouraged Apache to cooperate with 
other interested parties to minimize the impacts of new seismic surveys 
in the region. Currently, Apache works with other oil and gas operators 
in the area to enter into cooperative agreements. Sometimes these 
negotiations are successful, but at other times the companies cannot 
reach an agreement acceptable to both parties. Apache will continue its 
discussions with other operators in Cook Inlet to find opportunities to 
joint venture in oil and gas operations, including seismic data 
acquisition.
    Comment 5: The Commission recommended that NMFS correct the 
estimated distance to the 190 dB threshold for the offshore surveys to 
0.18 km.
    Response: The maximum distance to the 190 dB threshold for the 
channel surveys should be 0.18 km not 1.18 km. The information in Table 
2 of the proposed IHA (77 FR 73434, December 10, 2012) is correct and 
Table 4 should read 0.18 km not 1.18 km. NMFS regrets the unintentional 
error and apologizes for any confusion caused by the discrepancy.
    Comment 6: The Commission recommended that NMFS require that Apache 
either amend its application to seek authorization for the maximum 
number of marine mammals that may be taken or provide sufficient and 
consistent justification for requiring fewer takes, particularly of 
beluga whales, harbor porpoises, and harbor seals.
    Response: To provide some allowance for the uncertainties, Apache 
calculated both ``maximum estimates'' as well as ``average estimates'' 
of the numbers of marine mammals that could potentially be affected. 
For a few marine mammal species, several density estimates were 
available, and in those cases the mean and maximum estimates were 
determined from the survey data. In other cases, no applicable density 
estimate (or perhaps a single estimate) was available, so adjustments 
were used to arrive at ``average'' and ``maximum'' estimates. The 
species-specific estimation of these numbers is provided in Table 5 of 
the Federal Register notice for the proposed IHA (77 FR 73434, December 
10, 2012). NMFS has determined that the average density data of marine 
mammal populations will be used to calculate estimated take numbers for 
species commonly reported in the vicinity of seismic survey 
operations--harbor seals and harbor porpoises--because using maximum 
density numbers for these species will result in overestimates that do 
not account for marine mammals avoiding the sound source before they 
are in the harassment zones. For killer whales and Steller sea lions, 
which have been documented in the past but whose occurrence is rare or 
whose average densities are too low to yield a take number due to 
extra-limital distribution in the vicinity of the proposed survey area, 
NMFS used the maximum densities to calculate takes of these species. 
For Cook Inlet beluga whales, NMFS has consulted with the beluga whale 
experts at NOAA's National Marine Mammal Laboratory (NMML), which 
directed NMFS to a recently published habitat model developed for Cook 
Inlet beluga whales that provides densities throughout the inlet based 
on the data from aerial surveys (Goetz et al., 2012), and offered to 
conduct an analysis that would apply the model to Apache's seismic 
survey for the purpose of estimating beluga whale densities and takes. 
Additional information on the habitat-based model and the results of 
NMML's analysis are provided below in the Estimated Takes of Marine 
Mammals and Basis for Estimating ``Take by Harassment'' sections of 
this notice.
    Comment 7: The Commission recommended that NMFS include harbor 
porpoises as one of the species for which implementation of delay and 
shutdown procedures are required when observers detect aggregations of 
five or more animals approaching or within the 160 dB harassment zone, 
based on studies reporting that harbor porpoises are particularly 
sensitive to air gun sounds.
    Response: We agree with the proposal from the Commission regarding 
mitigation. These measures will be implemented if groups of five or 
more harbor porpoises are seen approaching or within the 160 dB zone.
    Comment 8: The Commission states that the proposed monitoring 
measures do not appear adequate to monitor the disturbance (160 dB) 
zone and determine whether the requested numbers of takes have been 
exceeded. The Commission recommended that NMFS ensure that the 
monitoring measures included in the authorization are sufficient to 
account for all takes of marine mammals and require Apache to provide 
timely reports of the numbers of marine mammals taken so that, if 
necessary, surveys can be stopped before the authorized takes are 
exceeded--the measures used should account not only for the marine 
mammals observed, but also those marine mammals that are present but 
not observed.
    Response: Section 101(a)(5)(D)(ii)(III) of the MMPA requires IHAs 
to include requirements pertaining to the monitoring and reporting of 
such taking by harassment. NMFS' implementing regulations at 50 CFR 
216.108(c) state that a monitoring program must, if appropriate, 
document the effects (including acoustical) on marine mammals and 
document or estimate the actual level of take. As the cited regulation 
suggests, monitoring is not required to document all takes that may 
occur. The monitoring measures for Apache's seismic surveys include 
standard methods contained in IHAs for industry and research-related 
seismic survey activities to monitor takings (and they are also used to 
implement mitigation (i.e., the prescribed means of effecting the least 
practicable impact)). Given the size of the estimated Level B 
harassment zone, we acknowledge that some marine mammals within or 
entering the zone may not be immediately detected. However, the suite 
of required monitoring for this survey--vessel-based, shore-based, and 
aerial--allows for sufficient monitoring of effects and level of take 
(it also provides monitoring for purposes of triggering mitigation). 
The results of the monitoring report for the 2012 survey support this 
finding. Moreover, some of the required mitigation, namely the ramp-up 
and use of a mitigation air gun at night, is designed to prevent more 
serious types of take that could occur if a marine mammal were to be in 
the safety zone undetected. NMFS acknowledges that monitoring at night 
or in reduced visibility is more difficult, but observes that (1) the 
great majority of Apache's 2012 survey occurred when full visual 
monitoring was available (given the longer day during the main months 
of operation), which is likely to be true for the 2013 survey as well, 
and (2) prohibiting operations during nighttime and periods of lower 
visibility would reduce operational flexibility and lengthen the survey 
period, increasing the potential for interactions with marine mammals.
    With respect to timely reporting, to better account for marine 
mammal takes that occur during the survey and ensure that takes do not 
exceed the amount authorized in the IHA, NMFS has included an 
additional reporting requirement in the IHA that will require the 
applicant to submit weekly and monthly reports to the Permits and 
Conservation Division. These reports will contain information regarding 
the species detected, in-water activity occurring at the time of the 
sighting,

[[Page 12723]]

behavioral reactions to in-water activities, and the number of marine 
mammals taken. NMFS believes that the inclusion of a weekly and monthly 
reporting requirement will allow both NMFS and Apache to regularly 
track the number and nature of marine mammal takes, and ensure that 
takes do not exceed what is authorized by the IHA. Apache must to 
report to NMFS immediately if 25 belugas are detected in the Level B 
harassment zone to allow us to consider making necessary adjustments to 
monitoring and mitigation. NMFS will require that seismic survey 
operations involving the use of air guns and pingers cease if 30 beluga 
whales are detected in the Level B harassment zone.
    Comment 9: The Commission recommended that NMFS provide a 30-day 
public review and comment period that starts with the publication of 
the notices in the printed edition of the Federal Register.
    Response: Although NMFS requested that the notice of the proposed 
IHA be available for review immediately upon filing with the Federal 
Register, due to a clerical error, the public review and comment period 
reflected the publication date of the notice; therefore, the public 
review and comment period for the proposed IHA did, in fact, start with 
publication in the Federal Register.
    Comment 10: The Alaska Department of Natural Resources and Kenaitze 
Indian Tribe support issuance of the IHA and appreciate Apache's 
commitment to ensuring that activities in the Cook Inlet region result 
in responsible resource development.
    Response: NMFS appreciates the review conducted by the State and 
Tribal natural resource managers and the continued collaboration and 
cooperation between the State of Alaska and Apache.
    Comment 11: Environmental NGOs commented that NMFS failed to 
properly estimate take by adopting Apache's analysis that contains 
errors in its density calculations.
    Response: The revised density and take estimates are provided in 
the Estimated Takes of Marine Mammals and Basis for Estimating ``Take 
by Harassment'' sections of this notice.
    Comment 12: Environmental NGOs commented that NMFS underestimated 
the size of Apache's impact area by: (1) Relying on an outdated and 
incorrect threshold for behavioral take; (2) disregarding the best 
available evidence on the potential for temporary and permanent 
threshold shift on mid- and high-frequency cetaceans and on pinnipeds; 
and (3) failing to calculate take using in situ propagation analysis.
    Response: The comment that NMFS uses an outdated and incorrect 
threshold for behavioral takes does not include any specific 
recommendations. NMFS uses 160 dB as the exposure level for calculating 
Level B harassment takes for most species in most cases. This threshold 
was established for underwater sound sources (except explosives and 
tactical active sonar) based on measured avoidance responses observed 
in whales in the wild. Specifically, the 160 dB threshold was derived 
from data for mother-calf pairs of migrating gray whales (Malme et al., 
1983, 1984) and bowhead whales (Richardson et al., 1985, 1986) 
responding to seismic air guns (e.g., impulsive sound source). We 
acknowledge there is more recent information bearing on behavioral 
reactions to seismic air guns, but those data only illustrate how 
complex and context-dependent the relationship is between the two. See 
75 FR 49710, 49716 (August 13, 2010) (IHA for Shell seismic survey in 
Alaska; response to comment 9). Accordingly, it is not a matter of 
merely replacing the existing threshold with a new one. NOAA is 
developing relatively sophisticated new draft guidelines for 
determining acoustic impacts, including information for determining 
Level B harassment thresholds. The draft guidelines will undergo a 
rigorous review that includes internal agency review, public notice and 
comment, and peer review before any final product is published. In the 
meantime, and taking into consideration the facts and available 
science, NMFS is using the 160 dB threshold for estimating takes of 
marine mammals in Cook Inlet by Level B harassment.
    The comment that NMFS disregarded the best available evidence on 
the potential for temporary and permanent threshold shift on mid- and 
high-frequency marine mammals and pinnipeds does not contain any 
specific recommendations. We acknowledge there is more recent 
information available bearing on the relevant exposure levels for 
assessing temporary and permanent hearing impacts. Again, NMFS will be 
issuing new draft acoustic guidelines, but that process is not complete 
so we did not use it to assign new thresholds for calculate take 
estimates for hearing impacts. However, we did consider the information 
and it suggests the current 180 and 190 dB thresholds are conservative 
in that they likely overestimate potential for hearing impacts. See 75 
FR 49710, 49715, 49724 (August 13, 2010) (IHA for Shell seismic survey 
in Alaska; responses to comment 8 and comment 27). Moreover, the 
required mitigation is designed to ensure there are no exposures to 
those injury thresholds.
    As for in situ propagation analysis, Apache plans to conduct a 
Sound Source Verification (SSV) study prior to commencing seismic 
survey operations in Area 2. If the results from the SSV study show 
that the harassment zones are larger than anticipated, Apache will 
adjust the zones and monitor based on the new information as needed.
    Comment 13: Environmental NGOs comment that the proposed IHA fails 
to properly evaluate the impacts of stress, the risk of stranding, 
potential reduction in prey, effects of increased turbidity, and 
cumulative impacts from other activities in Cook Inlet.
    Response: NMFS provided a detailed discussion of the potential 
effects of this action in the notice of the proposed IHA (77 FR 73434, 
December 10, 2012) and believes the analyses and preliminary 
determinations were appropriate. The comment does not provide any 
specific recommendations or criticism regarding the sufficiency of 
those analyses. The potential effects of this action are also 
adequately addressed in NMFS's Environmental Assessment and Biological 
Opinion (which is incorporated by reference herein).
    See response to Comment 3 for information on NMFS' cumulative 
effects analysis.
    Comment 14: Environmental NGOs comment that the IHA fails to 
justify adequately the specific level of take it would authorize, 
particularly given its analysis showing average and maximum take 
numbers that exceed the proposed authorization.
    Response: See response to Comment 6.
    Comment 15: Environmental NGOs comment that NMFS provides 
inadequate justification for its small numbers and negligible impact 
determinations.
    Response: This general comment contained no specific criticism or 
recommendations. NMFS believes the proposed and final IHA Federal 
Register notices contain sufficient justification for both the small 
numbers and negligible impact determinations. NMFS' conclusions 
regarding small numbers and negligible impact are provided in the 
Determinations section of this notice.
    Comment 16: Environmental NGOs comment that NMFS has failed to 
adequately consider the current beluga population level and trends, or 
the fact that it is likely that subsistence use of whales will be 
prohibited for many years into the future in its analysis

[[Page 12724]]

regarding whether the proposed survey will have an ``unmitigable 
adverse impact'' on the subsistence harvest.
    Response: Under NMFS MMPA implementing regulations at 50 CFR 
216.103, unmitigable adverse impact means an impact resulting from the 
specified activity: (1) That is likely to reduce the availability of 
the species to a level insufficient for a harvest to meeting 
subsistence needs by: (i) Causing the marine mammal to abandon or avoid 
hunting areas; (ii) directly displacing subsistence users; or (iii) 
placing physical barriers between the marine mammals and the 
subsistence hunters; and (2) that cannot be sufficiently mitigated by 
other measures to increase the availability of marine mammals to allow 
subsistence needs to be met. Currently there is no subsistence hunting 
of Cook Inlet belugas authorized (73 FR 60976, October 15, 2008). There 
can be no impacts on Cook Inlet beluga subsistence uses in the 
immediate future because they are not permitted. Moreover, any takes 
that occur from this IHA will not have impacts on future subsistence 
hunts for belugas if and when they resume because the anticipated takes 
are not expected to have any of the effects contemplated in NMFS' 
definition (above) of unmitigable adverse impact. Apache did not 
request and NMFS does not anticipate, nor is it authorizing, any Level 
A harassment takes of Cook Inlet beluga whales or takes by mortality 
incidental to the seismic surveys. The required mitigation and 
monitoring measures are designed to avoid exposing any marine mammals, 
including Cook Inlet beluga whales, to sound levels that may result in 
injury. For example, protected species observers will monitor the 
marine mammal exclusion zone while a sound source is active and have 
the authority to require power-downs or shut-downs to ensure that Level 
A harassment takes do not occur. In the unlikely event that marine 
mammals are exposed to potentially injurious levels of sound, the IHA 
will require Apache to cease work and report the incident to NMFS.
    Comment 17: Environmental NGOs comment that the mitigation measures 
proposed for the Apache survey fail to meet the MMPA's ``least 
practicable adverse impact'' standard, and provide a list of 
approximately eight measures that NMFS ``failed to consider or 
adequately consider.''
    Response: NMFS provided a detailed discussion of proposed 
mitigation measures and the MMPA's ``least practicable adverse impact'' 
standard in the notice of the proposed IHA (77 FR 73434, December 10, 
2012), which are repeated in the Mitigation section of this notice. The 
measures that NMFS allegedly failed to consider or adequately consider 
are identified and discussed below:
    (1) Seasonal exclusions around river mouths, including the Beluga 
River: Due to the location of the 2013 seismic survey, NMFS has added a 
10 mile (16 km) exclusion zone around the Susitna Delta (which includes 
the Beluga River) to the IHA. This mitigation mirrors a measure in the 
Incidental Take Statement for the 2012 and 2013 Biological Opinions. 
Seismic surveys operations involving the use of air guns will be 
prohibited in this area between April and October. (In addition, the 
Alaska Department of Fish and Game (ADF&G) prohibits the use of air 
guns within 1 mile (1.6 km) of the mouth of any stream listed by the 
ADF&G on the Catalogue of Waters Important for the Spawning, Rearing, 
or Migration of Anadromous Fishes.) See additional explanation in 
``Mitigation Measures Considered but not Required'' section, below.
    (2) Use of advance aerial surveys to redirect activity if 
sufficient numbers of belugas or other species are sighted: Safety and 
weather permitting, aerial surveys will occur daily. Aerial surveys 
will be required when operating near river mouths to identify large 
congregations of beluga whales and harbor seal haul outs. In addition, 
daily aerial surveys must be conducted when there are any seismic-
related activities (including, but not limited to, node laying/
retrieval or air gun operations) occurring north or east of a line from 
Tyonek across to the eastern side of Number 3 Bay of the Captain Cook 
State Recreation Area, Cook Inlet (roughly the southern-most point of 
Corps defined Region 9). The purposes of these surveys is to mitigate 
impacts and reduce incidental take by identifying the presence of Cook 
Inlet belugas near the Susitna Delta and alert the vessels accordingly 
of necessary actions to avoid or minimize potential disturbance, to 
monitor the effects of the seismic program on Cook Inlet belugas and 
their primary feeding and reproduction areas, and to ensure that any 
displacement from the Susitna Delta region is temporary and would not 
be likely to cause harm to whales by reducing their ability to feed. 
This information allows for better planning by PSOs and assists in 
better understanding of the movements of large groups of beluga whales 
with respect to the tide. Moreover, aerial observations can be used to 
locate rarely seen animals (e.g., gray whales) that are difficult to 
track from the vessels.
    (3) Field testing and use of alternative technologies, such as 
vibroseis and gravity gradiometry, to reduce or eliminate the need for 
air guns: Apache requested takes of marine mammals incidental to the 
seismic survey operations described in the IHA application, which 
identified air guns arrays as the technique Apache would employ to 
acquire seismic data. It would be impractical for NMFS to require 
Apache to make this kind of change to the underlying activity and is 
beyond the scope of the request for takes incidental to Apache's 
operation of air guns and other active acoustic sources.
    (4) Independent determination and required use of the lowest 
practicable source level in conducting air gun activity: This general 
comment contained no specific recommendations. Apache determined the 
array sizes during the test line surveyed in March 2011 and utilizes 
the minimum source level necessary to image the sub-surface targets.
    (5) Observance of a 10 knot speed limit for all vessels, including 
supply vessels, employed in the activity: NMFS does not agree with the 
recommendation that vessels observe a 10 knot speed limit. Stipulating 
vessel speeds would severely hamper Apache's seismic survey, increase 
the amount of time needed to complete the survey, and would not be 
practicable. In any event, Apache has indicated that vessels typically 
move at 2-4 knots during seismic surveys and NMFS requires speed and 
course alterations when a marine mammal is detected outside the 160 dB 
zone and, based on position and relative motion, is likely to enter the 
zone.
    (6) Limitation of the mitigation air gun to the longest shot 
interval necessary to carry out its intended purpose: This general 
comment contained no specific recommendations. Apache set the 
mitigation gun interval to mimic the timing of the shot interval used 
for the full array (approximately 24 seconds). NMFS believes that the 
shot interval of the mitigation air gun is appropriate to carry out its 
intended purpose.
    (7) Immediate suspension of air gun activity, pending 
investigation, if any beluga strandings occur within or within an 
appropriate distance of the Area 2 survey: There is no evidence in the 
literature that air gun pulses cause marine mammal strandings and the 
sounds produced by air guns are quite different from sound sources that 
have been associated with stranding events, such as military mid-
frequency active sonar. Nevertheless, the IHA requires Apache to 
immediately cease activities

[[Page 12725]]

and report unauthorized takes of marine mammals, such as injury, 
serious injury, or mortality. Activities cannot resume until NMFS is 
able to review the circumstances of the unauthorized take, determine 
what is necessary to minimize the likelihood of further unauthorized 
take and ensure MMPA compliance. Apache may not resume activities until 
notified by NMFS.
    (8) Establishment of a larger exclusion zone for beluga whales that 
is not predicated on the detection of cow-calf pairs: This comment does 
not provide any justification for why the exclusion (safety) zone for 
beluga whales (other than groups of five or more and cow-calf pairs) 
should be expanded beyond the 180 dB zone. We not that prior to 
commencing seismic survey activities in 2013, Apache will conduct 
another sound source verification study to measure the distance to the 
180/190 dB safety zone and to the 160 dB harassment zone. If the sound 
source verification study reveals that the distance is greater than the 
distances measures prior to the 2012 seismic survey, the zones and 
monitoring will be expanded as needed. Apache is required to shut down 
active sound sources if groups of five or more beluga whales, killer 
whales, and harbor porpoises or beluga cow-calf pairs are observed 
within or approaching the 160 dB zone.
    Comment 18: Environmental NGOs comment that monitoring measures 
should include passive acoustic monitoring superior to over-the-side 
hydrophone, require aerial-based monitoring in areas other than river 
mouths, and at least 2 ship-based PSOs per vessel on watch at all times 
during daylight hours with a maximum of 2 consecutive hours on watch 
and 8 hours of watch time per day per PSO.
    Response: The passive acoustic monitoring plan for Apache's 2012 
survey anticipated the use of a bottom-mounted telemetry buoy to 
broadcast acoustic measurements using a radio-system link back to a 
monitoring vessel. Although a buoy was deployed during the first week 
of surveying under the 2012 IHA, it was not successful. Upon 
deployment, the buoy immediately turned upside down due to the strong 
current in Cook Inlet. After retrieval, the buoy was not redeployed and 
the survey used a single omni-directional hydrophone lowered from the 
side of the mitigation vessel. During the entire 2012 survey season, 
Apache's PAM equipment yielded only six confirmed marine mammal 
detections, one of which was a Cook Inlet beluga whale. The single Cook 
Inlet beluga whale detection did not, however, result in a shutdown 
procedure. Given the limited capability of this particular PAM 
methodology for Apache's project in Cook Inlet (see Austin and Zeddies, 
2012 for more information), as compared to visual monitoring methods, 
including expanded daily aerial surveys, the bottom-mounted telemetry 
buoy and omni-directional hydrophone are no longer considered 
practicable, and will not be a component of the 2013 seismic survey.
    The IHA requires aerial surveys when operating near river mouths. 
In addition, NMFS has added the following monitoring measure: Safety 
and weather permitting, aerial surveys must be conducted when there are 
any seismic-related activities (including but not limited to node 
laying/retrieval or airgun operations) occurring north or east of a 
line from Tyonek across to the eastern side of Number 3 Bay of the 
Captain Cook State Recreation Area, Cook Inlet (roughly the southern-
most point of Corps defined Region 9). Surveys are to be flown even if 
the air guns are not being fired.
    Vessel-based observers are stationed on three vessels with two PSOs 
on the support vessel and one PSO on each of the two source vessels. 
Due to space limitations onboard the source vessels, no more than one 
PSO could be accommodated on each vessel. PSOs monitored for marine 
mammals during all daylight hours prior to and during seismic survey 
operations, unless precluded by weather (e.g., fog, ice, high sea 
states). PSOs on the vessels rotated observation shifts every 4-6 hours 
in order to better monitor the survey area, implement mitigation 
measures, and avoid fatigue. In addition, vessel crews are be 
instructed to assist with detecting marine mammals and implementing 
mitigation measures.
    Comment 19: The IAGC encouraged NMFS to review a recent peer-
reviewed scientific paper regarding the impacts of seismic surveys on 
fish. They referred NMFS to a study by Lokkeborg et al. (2012) that 
provides additional, updated information challenging the Engas et al. 
(1993) assessment that seismic surveys have adverse impacts on 
Norwegian fisheries.
    Response: NMFS acknowledges this comment and has reviewed the study 
by Lokkeborg et al. (2012), which was published in the Canadian Journal 
of Fisheries Aquatic Sciences on July 10, 2012. However, this does not 
change the analysis provided in the notice of the proposed IHA (77 FR 
73434, December 10, 2012).
    Comment 20: The IAGC encouraged NMFS to consider frequency 
weighting in development of incidental take estimates.
    Response: Frequency weighting takes into account that all marine 
mammal species do not have identical hearing capabilities. To reflect 
this, Southall et al. 2007 proposed that marine mammals be divided into 
five functional hearing groups and subsequently recommended frequency 
weighting functions for each of these groups. NMFS agrees that taking 
into account frequencies that marine mammals hear is an important 
consideration. For example, if a sound is entirely outside the hearing 
range of a species, it is not considered to have the potential to cause 
a significant response.
    There are data to indicate that frequency weighting is an important 
consideration associated with noise-induced hearing loss (Finneran and 
Schlundt, 2009; Finneran and Schlundt, 2011). We are in the process of 
reviewing and considering these data within our updated marine mammal 
NOAA acoustic guidelines. Southall et al., 2007 recommended criteria 
for onset of injury (i.e., permanent threshold shift) are presented 
using a cumulative sound exposure level, which takes into account not 
only the received level during exposure but also the duration of 
exposure, as well as incorporating frequency weighting functions. In 
situations where exposures of lower level but longer duration are 
possible (which could be possible for resident populations or 
population with a small range), there must be caution using the 
Southall et al., 2007 criteria (i.e., noise-induced hearing loss my 
occur at a lower level than shorter exposures of higher level but with 
the same cumulative sound exposure level; Mooney et al., 2009, Finneran 
et al., 2010).
    For behavior, the relationship between severity of response and 
frequency weighting is less clear and does not necessarily correspond 
to the severity of behavioral response expected. Behavioral effects are 
more challenging to predict since they often involve other variables 
beyond detection (e.g. perception and cognition, contextual cues, and 
previous experience). Despite most of the acoustic energy from seismic 
activities occurring outside the best hearing range of odontocetes, 
there are data showing that these species do behaviorally respond to 
these types of activities in some contexts, although not necessarily in 
a biologically significant way. Miller et al. (2005) indicates that 
belugas in the Beaufort Sea may have responded (avoidance) to seismic 
activity, although belugas may have already been in the

[[Page 12726]]

process of leaving the area due to their seasonal migration.
    Comment 21: The IAGC commented that NMFS should provide 
Environmental Assessments, Biological Opinions, and other documents for 
review at the same time as the proposed IHA.
    Response: In the notice of the proposed IHA (77 FR 73434, December 
10, 2012), NMFS indicated that an Environmental Assessment (EA) was 
being prepared and would be completed prior to NMFS' decision to issue 
or deny the IHA. The Environmental Assessment and Biological Opinion 
prepared for the IHA NMFS issued to Apache in April 2012 have been 
available and posted at https://www.nmfs.noaa.gov/pr/permits/incidental.htm. The information in those publically available documents 
provided a basis for the EA we prepared for the subject IHA. All 
comments on the proposed IHA that were also relevant to the effects of 
our action on the affected environment were considered.
    Based on changed in the proposed action, namely the potential 
survey area, we reinitiated section 7 consultation and a new biological 
opinion was issued. The time needed to conduct consultations does not 
allow for prior public review.
    Comment 22: The Seldovia Village Tribe opposed the operation of 
seismic air guns unless NMFS required that the activities cease when 
marine mammals are within or approaching the Level A harassment 
(injury) zone.
    Response: As described in detail in the notice of the proposed IHA 
(77 FR 73434, December 10, 2012), as well as in this document, NMFS 
does not believe that Apache's seismic survey will cause injury or 
mortality to marine mammals. NMFS requires that Apache establish, 
monitor, and implement mitigation measures in an area where sound has 
the potential to cause injury. NMFS mitigation or shutdown ``safety 
radii'' for limiting marine mammal exposure to impulsive sources 
typically correspond to the distances within which received sound 
levels are greater than or equal to 180 dB for cetaceans and greater 
than or equal to 190 dB for pinnipeds. These safety criteria are based 
on an assumption that SPLs received at lower levels will not result in 
injury or impair hearing. During Apache's survey, these ``safey zones'' 
will be monitored by PSOs for the presence of marine mammals and air 
guns will be shut down if marine mammals are observed approaching or 
within these zones. No injury and/or mortality of marine mammals is 
expected, and none was authorized.

Description of Marine Mammals in the Area of the Specified Activity

    The marine mammal species under NMFS's jurisdiction that could 
occur near operations in Cook Inlet include three cetacean species, all 
odontocetes (toothed whales): Beluga whale (Delphinapterus leucas), 
killer whale (Orcinus orca), and harbor porpoise (Phocoena phocoena), 
and two pinniped species: Harbor seal (Phoca vitulina richardsi) and 
Steller sea lions (Eumetopias jubatus). The marine mammal species that 
is likely to be encountered most widely (in space and time) throughout 
the period of the planned surveys is the harbor seal.
    Of the five marine mammal species likely to occur in the proposed 
marine survey area, only Cook Inlet beluga whales and Steller sea lions 
are listed as endangered under the ESA (Steller sea lions are listed as 
two distinct population segments (DPSs), an eastern and a western DPS; 
the relevant DPS in Cook Inlet is the western DPS). These species are 
also designated as ``depleted'' under the MMPA. Despite these 
designations, Cook Inlet beluga whales and the western DPS of Steller 
sea lions have not made significant progress towards recovery. The Cook 
Inlet population of beluga whales has been decreasing at a rate of 1.1 
percent annually for nearly a decade (Allen and Angliss, 2011). With 
respect to Steller sea lions, results of aerial surveys conducted in 
2008 (Fritz et al., 2008) confirmed that the recent (2004-2008) overall 
trend in the western population of adult and juvenile Steller sea lions 
in Alaska is stable or possibly in decline; however, there continues to 
be considerable regional variability in recent trends. Pursuant to the 
ESA, critical habitat has been designated for Cook Inlet beluga whales 
and Steller sea lions. The proposed action falls within critical 
habitat designated in Cook Inlet for beluga whales, but is not within 
critical habitat designated for Steller sea lions. The portion of 
beluga whale critical habitat--identified as Area 2 in the critical 
habitat designation--where the seismic survey will occur is located 
south of the Area 1 critical habitat where belugas are particularly 
vulnerable to impacts due to their high seasonal densities and the 
biological importance of the area for foraging, nursery, and predator 
avoidance. Area 2 critical habitat is largely based on dispersed fall 
and winter feeding and transit areas in waters where whales typically 
appear in smaller densities or deeper waters (76 FR 20180, April 11, 
2011).

Cetaceans

    Beluga Whales--Cook Inlet beluga whales reside in Cook Inlet year-
round although their distribution and density changes seasonally. 
Factors that are likely to influence beluga whale distribution within 
the inlet include prey availability, predation pressure, sea-ice cover, 
and other environmental factors, reproduction, sex and age class, and 
human activities (Rugh et al., 2000; NMFS 2008). Seasonal movement and 
density patterns as well as site fidelity appear to be closely linked 
to prey availability, coinciding with seasonal salmon and eulachon 
concentrations (Moore et al., 2000). For example, during spring and 
summer, beluga whales are generally concentrated near the warmer waters 
of river mouths where prey availability is high and predator occurrence 
in low (Huntington 2000; Moore et al., 2000). During the winter 
(November to April), belugas disperse throughout the upper and mid-
inlet areas, with animals found between Kalgin Island and Point 
Possession (Rugh et al., 2000). During these months, there are 
generally fewer observations of beluga whales in the Anchorage and Knik 
Arm area (NMML 2004; Rugh et al., 2004).
    Beluga whales use several areas of the upper Cook Inlet for 
repeated summer and fall feeding. The primary hotspots for beluga 
feeding include the Big and Little Susitna rivers, Eagle Bay to Eklutna 
River, Ivan Slough, Theodore River, Lewis River, and Chickaloon River 
and Bay (NMFS 2008). Availability of prey species appears to be the 
most influential environmental variable affecting Cook Inlet beluga 
whale distribution and relative abundance (Moore et al. 2000). The 
patterns and timing of eulachon and salmon runs have a strong influence 
on beluga whale feeding behavior and their seasonal movements (Nemeth 
et al., 2007; NMFS 2008). The presence of prey species may account for 
the seasonal changes in beluga group size and composition (Moore et 
al., 2000). Aerial and vessel-based monitoring conducted by Apache 
during the March 2011 2D test program in Cook Inlet reported 33 beluga 
sightings. One of the sightings was of a large group (~25 individuals 
on March 27, 2011) of feeding/milling belugas near the mouth of the 
Drift River. Also on March 27, 2011, PSOs onboard the M/V Dreamcatcher 
reported a group of seven beluga whales approximately 0.5 nm from the 
vessel. Land-based PSOs were able to observe this group of beluga

[[Page 12727]]

whales for approximately 2.5 hrs. A single beluga whale was observed 
near the mouth of the Drift River by the aerial-based monitors on March 
28, 2011, prior to the seismic ramp-up period. If belugas are present 
during the late summer/early fall, they are more likely to occur in 
shallow areas near river mouths in upper Cook Inlet. For example, no 
beluga whales were sighted in Trading Bay during the SSV conducted in 
September 2011 because during this time of year they are more likely to 
be in the upper regions of Cook Inlet. In the notice of the proposed 
IHA (77 FR 73434, December 10, 2012), expected densities were 
calculated from the annual aerial surveys conducted by NMFS between 
2000 and 2012 (Rugh et al. 2000, 2001, 2002, 2003, 2004, 2005, 2006, 
2007; Shelden et al. 2008, 2009, 2010, 2012; Hobbs et al. 2011). Those 
densities were presented in Table 5 of the proposed IHA. During the 
public comment period, in response to NMFS' request to apply a 
correction factor to the beluga whale aerial survey data, Apache 
submitted updated density estimates for beluga whales that applied a 
correction factor based on previously published studies. For example, 
in Hobbs et al. (2000), the correction for whales in missed groups was 
1.015 (CV = 3%) for the years 1994-98 and 1.021 (CV = 1%) for the years 
1999 and 2000. In all the subsequent annual survey reports (2001-2011), 
the authors stated that the correction factors for that particular year 
are within the range for 1999-2000. Therefore, a correction factor of 
1.021 was applied to all of the highest number of sightings for each 
year and calculated the densities/takes the same as for the previous 
IHA. Using this correction factor, the estimated maximum take increased 
from 11.98 to 12.2 (12), so there was no difference from the previous 
uncorrected approach with respect to ``whole'' animals.
    After receiving the new information from Apache, NMFS sent the 
updated density estimates to beluga whale experts at the National 
Marine Mammal Laboratory (NMML) for their review. NMML staff indicated 
that Apache appeared to account for both on and off effort flight hours 
(instead of just on-effort hours) and had not included 1,810 km of 
coastline. NMML attempted to correct Apache's calculations by including 
on-effort survey hours and 1,810 km of coastline, but determined that 
the resulting take calculations for beluga whales were grossly 
inaccurate and unreliable. NMML staff directed NMFS to a published 
habitat model developed for Cook Inlet beluga whales that provides 
densities throughout the inlet based on the data from aerial surveys 
(Goetz et al., 2012), and agreed to conduct an analysis that would 
apply the habitat-based model to Apache's seismic survey for the 
purpose of estimating beluga whale densities and takes. Additional 
information on the habitat-based model and the results of NMML's 
analysis are provided below.
    Killer Whales--In general, killer whales are rare in upper Cook 
Inlet, where transient killer whales are known to feed on beluga whales 
and resident killer whales are known to feed on anadromous fish 
(Shelden et al., 2003). The availability of these prey species largely 
determines the likeliest times for killer whales to be in the area. 
Between 1993 and 2004, 23 sightings of killer whales were reported in 
the lower Cook Inlet during aerial surveys by Rugh et al. (2005). 
Surveys conducted over a span of 20 years by Shelden et al. (2003) 
reported 11 sightings in upper Cook Inlet between Turnagain Arm, 
Susitna Flats, and Knik Arm. No killer whales were spotted during 
recent surveys by Funk et al. (2005), Ireland et al. (2005), Brueggeman 
et al. (2007a, 2007b, 2008), or Prevel Ramos et al. (2006, 2008). 
Eleven killer whale strandings have been reported in Turnagain Arm, six 
in May 1991 and five in August 1993. Therefore, very few killer whales, 
if any, are expected to approach or be in the vicinity of the action 
area.
    Harbor Porpoise--The most recent estimated density for harbor 
porpoises in Cook Inlet is 7.2 per 1,000 km\2\ (Dahlheim et al., 2000) 
indicating that only a small number use Cook Inlet. Harbor porpoise 
have been reported in lower Cook Inlet from Cape Douglas to the West 
Foreland, Kachemak Bay, and offshore (Rugh et al., 2005). Small numbers 
of harbor porpoises have been consistently reported in upper Cook Inlet 
between April and October, except for a recent survey that recorded 
higher than usual numbers. Prevel Ramos et al. (2008) reported 17 
harbor porpoises from spring to fall 2006, while other studies reported 
14 in the spring of 2007 (Brueggeman et al. 2007) and 12 in the fall 
(Brueggeman et al. 2008). During the spring and fall of 2007, 129 
harbor porpoises were reported between Granite Point and the Susitna 
River; however, the reason for the increase in numbers of harbor 
porpoise in the upper Cook Inlet remains unclear and the disparity with 
the result of past sightings suggests that it may be an anomaly. The 
spike in reported sightings occurred in July, which was followed by 
sightings of 79 harbor porpoises in August, 78 in September, and 59 in 
October, 2007. It is important to note that the number of porpoises 
counted more than once was unknown, which suggests that the actual 
numbers are likely smaller than those reported. In addition, recent 
passive acoustic research in Cook Inlet by the Alaska Department of 
Fish and Game and the National Marine Mammal Laboratory have indicated 
that harbor porpoises occur in the area more frequently than previously 
thought, particularly in the West Foreland area in the spring (NMFS, 
2011); however overall numbers are still unknown at this time.

 Pinnipeds

    Two species of pinnipeds may be encountered in Cook Inlet: Harbor 
seal and Steller sea lion.
    Harbor Seals--Harbor seals inhabit the coastal and estuarine waters 
of Cook Inlet. In general, harbor seals are more abundant in lower Cook 
Inlet than in upper Cook Inlet, but they do occur in the upper inlet 
throughout most of the year (Rugh et al., 2005). Harbor seals are non-
migratory; their movements are associated with tides, weather, season, 
food availability, and reproduction. The major haulout sites for harbor 
seals are located in lower Cook Inlet and their presence in the upper 
inlet coincides with seasonal runs of prey species. For example, harbor 
seals are commonly observed along the Susitna River and other 
tributaries along upper Cook Inlet during the eulachon and salmon 
migrations (NMFS, 2003). During aerial surveys of upper Cook Inlet in 
2001, 2002, and 2003, harbor seals were observed 24 to 96 km south-
southwest of Anchorage at the Chickaloon, Little Susitna, Susitna, 
Ivan, McArthur, and Beluga Rivers (Rugh et al., 2005). During the 2D 
test program in March 2011, two harbor seals were observed by vessel-
based PSOs. On March 25, 2011, one harbor seal was observed 
approximately 400 m from the M/V Miss Diane. At the time of the 
observation, the vessel was operating the positioning pinger and PSOs 
instructed the operator to implement a shut-down. The pinger was shut 
down for 30 minutes while PSO monitored the area and re-started the 
device when the animal was not sighted again during the 30 minute site 
clearing protocol. No unusual behaviors were reported during the time 
the animal was observed. The second harbor seal was observed on March 
26, 2011, by vessel-based PSO onboard the M/V Dreamcatcher 
approximately 4260 m from the source vessel, which was operating the 10 
in\3\ air gun at the time. The animal was well outside of the 160 dB 
zone (330 m for the 10 in\3\ air gun) and no unusual behaviors were 
observed. Many harbor seals were observed during the 3D seismic survey

[[Page 12728]]

conducted under the April 2012 IHA, especially when survey operations 
were conducted close to shore. NMFS and Apache do not anticipate 
encountering large haulouts of seals in Area 2--the closest haulout 
site to the action area is located on Kalgin Island, which is 
approximately 22 km away from the McArthur River--but we do expect to 
see curious individual harbor seals; especially during large fish runs 
in the various rivers draining into Cook Inlet.
    Steller Sea Lion--Two separate stocks of Steller sea lions are 
recognized within U.S. waters: An eastern U.S. stock, which includes 
animals east of Cape Suckling, Alaska; and a western U.S. stock, which 
includes animals west of Cape Suckling (NMFS, 2008). Individuals in 
Cook Inlet are considered part of the western U.S. stock, which is 
listed as endangered under the ESA. Steller sea lions primarily occur 
in lower, rather than upper Cook Inlet and are rarely sighted north of 
Nikiski on the Kenai Peninsula. Haul-outs and rookeries are located 
near Cook Inlet at Gore Point, Elizabeth Island, Perl Island, and 
Chugach Island (NMFS, 2008). No Steller seal lion haul-outs or 
rookeries are located in the vicinity of the proposed seismic survey. 
Furthermore, no sightings of Steller sea lions were reported by Apache 
during the 2D test program in March 2011. During the 3D seismic survey 
in 2012, Steller sea lions were observed on three separate occasions 
(approximately 4 individuals). Although Apache has requested takes of 
Steller sea lions, Steller sea lions would be rare in the action area 
during seismic survey operations.
    Apache's application contains additional information on the status, 
distribution, seasonal distribution, and abundance of each of the 
species under NMFS' jurisdiction mentioned in this document. Please 
refer to the application for that information (see ADDRESSES). 
Additional information can also be found in the NMFS Stock Assessment 
Reports (SAR). The Alaska 2011 SAR is available at: https://www.nmfs.noaa.gov/pr/pdfs/sars/ak2011.pdf.

Potential Effects of the Specified Activity on Marine Mammals

    NMFS considered the potential effects of sound from air guns, 
pingers, vessels, aircraft, and land-based explosives. In addition, 
NMFS considered the effects of vessel operations and the potential for 
ship strikes.

Potential Effects of Air Gun Sounds on Marine Mammals

    The effects of sounds from air gun pulses might include one or more 
of the following: Tolerance, masking of natural sounds, behavioral 
disturbance, and temporary or permanent hearing impairment or non-
auditory effects (Richardson et al., 1995). As outlined in previous 
NMFS documents, the effects of noise on marine mammals are highly 
variable, often depending on species and contextual factors, and can be 
categorized as follows (based on Richardson et al., 1995):
(1) Tolerance
    Numerous studies have shown that pulsed sounds from air guns are 
often readily detectable in the water at distances of many kilometers. 
Numerous studies have also shown that marine mammals at distances more 
than a few kilometers from operating survey vessels often show no 
apparent response. That is often true even in cases when the pulsed 
sounds must be readily audible to the animals based on measured 
received levels and the hearing sensitivity of that mammal group. In 
general, pinnipeds and small odotocetes (toothed whales) seem to be 
more tolerant of exposure to air gun pulses than baleen whales. 
Although various toothed whales, and (less frequently) pinnipeds have 
been shown to react behaviorally to air gun pulses under some 
conditions, at other times, mammals of both types have shown no overt 
reactions. For example, the available evidence also indicates that Cook 
Inlet beluga whales are less impacted behaviorally by anthropogenic 
sounds compared to marine mammals in more pristine acoustic 
environments (e.g., the Beaufort Sea) given the Cook Inlet population's 
greater experience with anthropogenic sounds.
(2) Behavioral Disturbance
    Marine mammals may behaviorally react to sound when exposed to 
anthropogenic noise. These behavioral reactions are often shown as: 
Changing durations of surfacing and dives, number of blows per 
surfacing, or moving direction and/or speed; reduced/increased vocal 
activities; changing/cessation of certain behavioral activities (such 
as socializing or feeding); visible startle response or aggressive 
behavior (such as tail/fluke slapping or jaw clapping); avoidance of 
areas where noise sources are located; and/or flight responses (e.g., 
pinnipeds flushing into water from haulouts or rookeries).
    The biological significance of many of these behavioral 
disturbances is difficult to predict, especially if the detected 
disturbances appear minor. However, the consequences of behavioral 
modification have the potential to be biologically significant if the 
change affects growth, survival, or reproduction. Examples of 
significant behavioral modifications include:
     Drastic change in diving/surfacing patterns (such as those 
thought to be causing beaked whale stranding due to exposure to 
military mid-frequency tactical sonar);
     Habitat abandonment due to loss of desirable acoustic 
environment; and
     Cessation of feeding or social interaction.
    The onset of behavioral disturbance from anthropogenic noise 
depends on both external factors (characteristics of noise sources and 
their paths) and the receiving animals (hearing, motivation, 
experience, demography) and is also difficult to predict (Southall et 
al., 2007).
    Currently NMFS uses a received level of 160 dB re 1 [mu]Pa to 
estimate the onset threshold for marine mammal behavioral harassment 
for impulse noises (such as air gun pulses). As explained below, NMFS 
has determined that use of this threshold is appropriate for Apache's 
IHA considering the scientific literature pertaining to this issue and 
the evidence specific to the marine mammal species and populations in 
question.
(3) Masking
    Marine mammals use acoustic signals for a variety of purposes, 
which differ among species, but include communication between 
individuals, navigation, foraging, reproduction, and learning about 
their environment (Erbe and Farmer, 2000; Tyack, 2000). Masking, or 
auditory interference, generally occurs when sounds in the environment 
are louder than, and of a similar frequency as, auditory signals an 
animal is trying to receive. Masking is a phenomenon that affects 
animals that are trying to receive acoustic information about their 
environment, including sounds from other members of their species, 
predators, prey, and sounds that allow them to orient in their 
environment. Masking these acoustic signals can disturb the biological 
functions of individual animals or groups of animals over long 
distances and times, which could potentially have population-level 
effects.
    Masking occurs when noise and signals (that the animal utilizes) 
overlap at both spectral and temporal scales. For the air gun noise 
generated from the

[[Page 12729]]

proposed seismic surveys, noise will consist of low frequency (under 
500 Hz) pulses with extremely short durations (less than one second). 
Lower frequency man-made noises are more likely to affect detection of 
communication calls and other potentially important natural sounds such 
as surf and prey noise. There is little concern regarding masking near 
the noise source due to the brief duration of these pulses and 
relatively longer silence between air gun shots (approximately 12 
seconds). However, at long distances (over tens of kilometers away), 
due to multipath propagation and reverberation, the durations of air 
gun pulses can be ``stretched'' to seconds with long decays (Madsen et 
al., 2006), although the intensity of the noise is greatly reduced.
    This could affect communication signals used by low frequency 
mysticetes when they occur near the noise band and thus reduce the 
communication space of animals (e.g., Clark et al., 2009) and cause 
increased stress levels (e.g., Foote et al., 2004; Holt et al., 2009); 
however, no baleen whales are expected to occur within the action area. 
Marine mammals are thought to be able to compensate for masking by 
adjusting their acoustic behavior by shifting call frequencies, and/or 
increasing call volume and vocalization rates. For example, blue whales 
are found to increase call rates when exposed to seismic survey noise 
in the St. Lawrence Estuary (Di Iorio and Clark, 2010). The North 
Atlantic right whales (Eubalaena glacialis) exposed to high shipping 
noise increase call frequency (Parks et al., 2007), while some humpback 
whales respond to low-frequency active sonar playbacks by increasing 
song length (Miller et al., 2000).
(4) Hearing Impairment
    Marine mammals exposed to high intensity sound repeatedly or for 
prolonged periods can experience hearing threshold shift (TS), which is 
the loss of hearing sensitivity at certain frequency ranges (Kastak et 
al., 1999; Schlundt et al., 2000; Finneran et al., 2002; 2005). TS can 
be permanent (PTS), in which case the loss of hearing sensitivity is 
unrecoverable, or temporary (TTS), in which case the animal's hearing 
threshold will recover over time (Southall et al., 2007). Just like 
masking, marine mammals that suffer from PTS or TTS could have reduced 
fitness in survival and reproduction, either permanently or 
temporarily. For transient sounds, the sound level necessary to cause 
TTS is inversely related to the duration of the sound.
    Researchers have studied TTS in certain captive odontocetes and 
pinnipeds exposed to strong sounds (reviewed in Southall et al., 2007). 
However, there has been no specific documentation of TTS let alone 
permanent hearing damage, i.e., permanent threshold shift (PTS), in 
free-ranging marine mammals exposed to sequences of air gun pulses 
during realistic field conditions.
    Temporary Threshold Shift--TTS is the mildest form of hearing 
impairment that can occur during exposure to a strong sound (Kryter, 
1985). While experiencing TTS, the hearing threshold rises and a sound 
must be stronger in order to be heard. At least in terrestrial mammals, 
TTS can last from minutes or hours to (in cases of strong TTS) days. 
For sound exposures at or somewhat above the TTS threshold, hearing 
sensitivity in both terrestrial and marine mammals recovers rapidly 
after exposure to the noise ends. Few data on sound levels and 
durations necessary to elicit mild TTS have been obtained for marine 
mammals, and none of the published data concern TTS elicited by 
exposure to multiple pulses of sound. Available data on TTS in marine 
mammals are summarized in Southall et al. (2007).
    To avoid the potential for injury, NMFS (1995, 2000) concluded that 
cetaceans and pinnipeds should not be exposed to pulsed underwater 
noise at received levels exceeding 180 and 190 dB re 1 [mu]Pa (rms), 
respectively. The 180 and 190 dB (rms) criteria are not considered to 
be the levels above which TTS might occur. Rather, they are the 
received levels above which, in the view of a panel of bioacoustics 
specialists convened by NMFS before TTS measurements for marine mammals 
started to become available, one could not be certain that there would 
be no injurious effects, auditory or otherwise, to marine mammals. NMFS 
also assumes that cetaceans and pinnipeds exposed to levels exceeding 
160 dB re 1 [mu]Pa (rms) may experience Level B harassment.
    For toothed whales, researchers have derived TTS information for 
odontocetes from studies on the bottlenose dolphin and beluga. The 
experiments show that exposure to a single impulse at a received level 
of 207 kPa (or 30 psi, p-p), which is equivalent to 228 dB re 1 Pa (p-
p), resulted in a 7 and 6 dB TTS in the beluga whale at 0.4 and 30 kHz, 
respectively. Thresholds returned to within 2 dB of the pre-exposure 
level within 4 minutes of the exposure (Finneran et al., 2002). For the 
one harbor porpoise tested, the received level of air gun sound that 
elicited onset of TTS was lower (Lucke et al., 2009). If these results 
from a single animal are representative, it is inappropriate to assume 
that onset of TTS occurs at similar received levels in all odontocetes 
(cf. Southall et al., 2007). Some cetaceans apparently can incur TTS at 
considerably lower sound exposures than are necessary to elicit TTS in 
the beluga or bottlenose dolphin.
    In pinnipeds, researchers have not measured TTS thresholds 
associated with exposure to brief pulses (single or multiple) of 
underwater sound. Initial evidence from more prolonged (non-pulse) 
exposures suggested that some pinnipeds (harbor seals in particular) 
incur TTS at somewhat lower received levels than do small odontocetes 
exposed for similar durations (Kastak et al., 1999, 2005; Ketten et 
al., 2001). The TTS threshold for pulsed sounds has been indirectly 
estimated as being an SEL of approximately 171 dB re 1 
[micro]Pa\2\[middot]s (Southall et al., 2007) which would be equivalent 
to a single pulse with a received level of approximately 181 to 186 dB 
re 1 [micro]Pa (rms), or a series of pulses for which the highest rms 
values are a few dB lower. Corresponding values for California sea 
lions and northern elephant seals are likely to be higher (Kastak et 
al., 2005).
    No cases of TTS are expected as a result of Apache's proposed 
activities given the strong likelihood that marine mammals would avoid 
the approaching air guns (or vessel) before being exposed to levels 
high enough for there to be any possibility of TTS, and the mitigation 
measures proposed to be implemented during the survey described later 
in this document.
    Permanent Threshold Shift--When PTS occurs, there is physical 
damage to the sound receptors in the ear. In severe cases, there can be 
total or partial deafness, whereas in other cases, the animal has an 
impaired ability to hear sounds in specific frequency ranges (Kryter, 
1985). There is no specific evidence that exposure to pulses of air gun 
sound can cause PTS in any marine mammal, even with large arrays of air 
guns. However, given the possibility that mammals close to an air gun 
array might incur at least mild TTS, there has been further speculation 
about the possibility that some individuals occurring very close to air 
guns might incur PTS (e.g., Richardson et al., 1995; Gedamke et al., 
2008). Single or occasional occurrences of mild TTS are not indicative 
of permanent auditory damage, but repeated or (in some cases) single 
exposures to a level well above that causing TTS onset might elicit 
PTS.
    Relationships between TTS and PTS thresholds have not been studied 
in

[[Page 12730]]

marine mammals, but are assumed to be similar to those in humans and 
other terrestrial mammals (Southall et al., 2007). PTS might occur at a 
received sound level at least several dBs above that inducing mild TTS 
if the animal were exposed to strong sound pulses with rapid rise 
times. Based on data from terrestrial mammals, a precautionary 
assumption is that the PTS threshold for impulse sounds (such as air 
gun pulses as received close to the source) is at least 6 dB higher 
than the TTS threshold on a peak-pressure basis, and probably greater 
than 6 dB (Southall et al., 2007).
    Given the higher level of sound necessary to cause PTS as compared 
with TTS, it is considerably less likely that PTS would occur during 
the proposed seismic survey in Cook Inlet. Cetaceans generally avoid 
the immediate area around operating seismic vessels, as do some other 
marine mammals. Some pinnipeds show avoidance reactions to air guns, 
but their avoidance reactions are generally not as strong or consistent 
as those of cetaceans, and occasionally they seem to be attracted to 
operating seismic vessels (NMFS, 2010).
(5) Non-auditory Physical Effects
    Non-auditory physical effects might occur in marine mammals exposed 
to strong underwater pulsed sound. Possible types of non-auditory 
physiological effects or injuries that theoretically might occur in 
mammals close to a strong sound source include stress, neurological 
effects, bubble formation, and other types of organ or tissue damage. 
Some marine mammal species (i.e., beaked whales) may be especially 
susceptible to injury and/or stranding when exposed to strong pulsed 
sounds. However, there is no definitive evidence that any of these 
effects occur even for marine mammals in close proximity to large 
arrays of air guns, and beaked whales do not occur in the proposed 
project area. In addition, marine mammals that show behavioral 
avoidance of seismic vessels, including most baleen whales, some 
odontocetes (including belugas), and some pinnipeds, are especially 
unlikely to incur non-auditory impairment or other physical effects. 
The distances to the 180 and 190 dB thresholds for the air gun arrays 
proposed to be used by Apache are provided in Table 1.
    Therefore, it is unlikely that such effects would occur during 
Apache's proposed surveys given the brief duration of exposure and the 
planned monitoring and mitigation measures described later in this 
document.
(6) Stranding and Mortality
    Marine mammals close to underwater detonations of high explosive 
can be killed or severely injured, and the auditory organs are 
especially susceptible to injury (Ketten et al., 1993; Ketten, 1995). 
Air gun pulses are less energetic and their peak amplitudes have slower 
rise times. To date, there is no evidence that serious injury, death, 
or stranding by marine mammals can occur from exposure to air gun 
pulses, even in the case of large air gun arrays.
    However, in numerous past IHA notices for seismic surveys, 
commenters have referenced two stranding events allegedly associated 
with seismic activities, one off Baja California and a second off 
Brazil. NMFS has addressed this concern several times, including in the 
Federal Register notice announcing the IHA for Apache's first seismic 
survey in 2012, and, without new information, does not believe that 
this issue warrants further discussion. For information relevant to 
strandings of marine mammals, readers are encouraged to review NMFS' 
response to comments on this matter found in 69 FR 74905 (December 14, 
2004), 71 FR 43112 (July 31, 2006), 71 FR 50027 (August 24, 2006), 71 
FR 49418 (August 23, 2006), and 77 FR 27720 (May 11, 2012).
    It should be noted that strandings related to sound exposure have 
not been recorded for marine mammal species in Cook Inlet. Beluga whale 
strandings in Cook Inlet are not uncommon; however, these events often 
coincide with extreme tidal fluctuations (``spring tides'') or killer 
whale sightings (Shelden et al., 2003). For example, in August 2012, a 
group of Cook Inlet beluga whales stranded in the mud flats of 
Turnagain Arm during low tide and were able to swim free with the flood 
tide. No strandings or marine mammals in distress were observed during 
the 2D test survey conducted by Apache in March 2011 and none were 
reported by Cook Inlet inhabitants. Furthermore, no strandings were 
reported during seismic survey operations conducted under the April 
2012 IHA. As a result, NMFS does not expect any marine mammals will 
incur serious injury or mortality in Cook Inlet or strand as a result 
of the proposed seismic survey.

Potential Effects From Pingers on Marine Mammals

    Active acoustic sources other than the air guns have been proposed 
for Apache's 2013 seismic survey in Cook Inlet. The specifications for 
the pingers (source levels and frequency ranges) were provided in the 
notice of the proposed IHA (77 FR 73434, December 10, 2012). In 
general, the potential effects of this equipment on marine mammals are 
similar to those from the air guns, except the magnitude of the impacts 
is expected to be much less due to the lower intensity of the source 
(i.e., an animal would need to be within 25 m of the boat to be exposed 
to received levels of sound above 160 dB, which is unlikely to occur 
without triggering mitigation).

Potential Effects From Vessels and Vessel Noise on Marine Mammals

    Vessel activity and noise associated with vessel activity will 
temporarily increase in the action area during Apache's seismic survey 
as a result of the operation of eight vessels. To minimize the effects 
of vessels and noise associated with vessel activity, Apache will 
follow NMFS' Marine Mammal Viewing Guidelines and Regulations and will 
alter heading or speed if a marine mammal gets too close to a vessel. 
In addition, vessels will be operating at slow speed (2-4 knots) when 
conducting surveys and in a purposeful manner to and from work sites in 
as direct a route as possible. Marine mammal monitoring observers and 
passive acoustic devices will alert vessel captains as animals are 
detected to ensure safe and effective measures are applied to avoid 
coming into direct contact with marine mammals. Therefore, NMFS neither 
anticipates nor authorizes takes of marine mammals from ship strikes.
    Odontocetes, such as beluga whales, killer whales, and harbor 
porpoises, often show tolerance to vessel activity; however, they may 
react at long distances if they are confined by ice, shallow water, or 
were previously harassed by vessels (Richardson, 1995). Beluga whale 
response to vessel noise varies greatly from tolerance to extreme 
sensitivity depending on the activity of the whale and previous 
experience with vessels (Richardson, 1995). Reactions to vessels 
depends on whale activities and experience, habitat, boat type, and 
boat behavior (Richardson, 1995) and may include behavioral responses, 
such as altered headings or avoidance (Blane and Jaakson, 1994; Erbe 
and Farmer, 2000); fast swimming; changes in vocalizations (Lesage et 
al., 1999; Scheifele et al., 2005); and changes in dive, surfacing, and 
respiration patterns.
    There are few data published on pinniped responses to vessel 
activity, and most of the information is anecdotal (Richardson, 1995). 
Generally, sea lions in water show tolerance to close and frequently 
approaching vessels and sometimes show interest in fishing

[[Page 12731]]

vessels. They are less tolerant when hauled out on land; however, they 
rarely react unless the vessel approaches within 100-200 m (330-660 ft; 
reviewed in Richardson, 1995).
    The addition of eight vessels and noise due to vessel operations 
associated with the seismic survey would not be outside the present 
experience of marine mammals in Cook Inlet, although levels may 
increase locally. Given the large number of vessels in Cook Inlet and 
the apparent habituation to vessels by Cook Inlet beluga whales and the 
other marine mammals that may occur in the area, vessel activity and 
noise is not expected to have effects that could cause significant or 
long-term consequences for individual marine mammals or their 
populations.

Potential Effects From Aircraft Noise on Marine Mammals

    Apache plans to utilize the crew helicopter or small fixed-wing 
aircraft to conduct aerial surveys in order to identify locations or 
congregations of beluga whales and other marine mammals prior to the 
commencement of operations. The aircraft should be used every day, but 
must be used for surveys near river mouths. In addition, weather and 
safety permitting, daily aerial surveys must be conducted when there 
are any seismic-related activities (including but not limited to node 
laying/retrieval or air gun operations) occurring north or east of a 
line from Tyonek across to the eastern side of Number 3 Bay of the 
Captain Cook State Recreation Area, Cook Inlet (roughly the southern-
most point of Corps defined Region 9). Surveys are to be flown even if 
the air guns are not being fired. Aerial surveys will fly at an 
altitude of 305 m (1,000 ft) when practicable and weather conditions 
permit. In the event of a marine mammal sighting, aircraft will try to 
maintain a radial distance of 457 m (1,500 ft) from the marine 
mammal(s). Aircraft will avoid approaching marine mammals from head-on, 
flying over or passing the shadow of the aircraft over the marine 
mammals.
    Studies on the reactions of cetaceans to aircraft show little 
negative response (Richardson et al., 1995). In general, reactions 
range from sudden dives and turns and are typically found to decrease 
if the animals are engaged in feeding or social behavior. Whales with 
calves or in confined waters may show more of a response. Generally 
there has been little or no evidence of marine mammals responding to 
aircraft overflights when altitudes are at or above 1,000 ft, based on 
three decades of flying experience in the Arctic (NMFS, unpublished 
data). Based on long-term studies that have been conducted on beluga 
whales in Cook Inlet since 1993, NMFS expect that there will be no 
effects of this activity on beluga whales or other cetaceans. No change 
in beluga swim directions or other noticeable reactions have been 
observed during the Cook Inlet aerial surveys flown from 600 to 800 ft. 
(e.g., Rugh et al., 2000). By applying the operational requirements 
discussed above, sound levels underwater are not expected to reach 
NMFS' harassment thresholds.
    The majority of observations of pinnipeds reacting to aircraft 
noise are associated with animals hauled out on land or ice. There are 
very little data describing the reactions of pinnipeds in water to 
aircraft (Richardson et al., 1995). In the presence of aircraft, 
pinnipeds hauled out for pupping or molting generally became alert and 
then rushed or slipped (when on ice) into the water. Stampedes often 
result from this response and may increase pup mortality due to 
crushing or an increase rate of pup abandonment. The greatest reactions 
from hauled out pinnipeds were observed when low flying aircrafts 
passed directly above the animal(s) (Richardson et al., 1995). Although 
noise associated with aircraft activity could cause hauled out 
pinnipeds to rush into the water, there are no known haul out sites in 
the vicinity of the survey site.
    Therefore, the operation of aircraft during the seismic survey is 
not expected to have effects that could cause significant or long-term 
consequences for individual marine mammals or their populations. To 
minimize the noise generated by aircraft, Apache will follow NMFS' 
Marine Mammal Viewing Guidelines and Regulations found at https://www.alaskafisheries.noaa.gov/protectedresources/mmv/guide.htm.

Land-Based Explosives

    The onshore component of the seismic survey involves the 
underground detonation of explosive devices to acquire seismic data on 
land. Because underwater sound levels associated with the land-based 
explosives were previously unknown, in September 2011, Apache conducted 
a SSV study, which found that marine mammals would not be exposed to 
underwater sound levels that exceed the NMFS injury or harassment 
thresholds.

Anticipated Effects on Marine Mammal Habitat

    NMFS included a detailed discussion of the potential effects of 
this action on marine mammal habitat, including physiological and 
behavioral effects on marine fish and invertebrates, in the notice of 
the proposed IHA (77 FR 73434, December 10, 2012). 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 site-specific. The main impact associated with 
the activity would be temporarily elevated noise levels and the 
associated direct effects on marine mammals.

Mitigation

    In order to issue an incidental take authorization 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 on the availability of such species 
or stock for taking for certain subsistence uses.
    To reduce the potential for disturbance from acoustic stimuli 
associated with the activities, Apache and/or its designees will 
implement the following mitigation measures for marine mammals:

(1) Operation of Mitigation Air Gun at Night

    Apache proposes to conduct both daytime and nighttime operations. 
Nighttime operations would only be initiated if a mitigation air gun 
(typically the 10 in\3\) has been continuously operational from the 
time that PSO monitoring has ceased for the day. The mitigation air gun 
would operate on a longer duty cycle than the full air gun arrays, 
firing every 30-45 seconds. Seismic activity would not ramp up from an 
extended shut-down (i.e., when the air gun has been down with no 
activity for at least 10 minutes) during nighttime operations and 
survey activities would be suspended until the following day because 
dedicated PSOs would not be on duty. At night, the vessel captain and 
crew would maintain lookout for marine mammals and would order the air 
gun(s) to be shut down if marine mammals are observed in or about to 
enter the established safety radii. After a shut down during night 
operations, seismic survey activities will be suspended until the 
following day when the full safety zone is visible.

(2) Safety and Disturbance Zones

    NMFS mitigation or shutdown ``safety radii'' for limiting marine 
mammal exposure to impulse sources typically

[[Page 12732]]

correspond to the distances within which received sound levels are 
>=180 dBrms re 1 [mu]Pa for cetaceans and >=190 
dBrms re 1 [mu]Pa for pinnipeds. These safety criteria are 
based on an assumption that SPLs received at levels lower than these 
will not injure these animals or impair their hearing abilities. 
Disturbance or behavioral effects to marine mammals from underwater 
sound may occur from exposure to sound at lower SPLs, at distances 
greater than the safety radii (Richardson et al., 1995). The 
disturbance zone is defined as the area between the 180/190 dB 
threshold and the 160 dB threshold where NMFS has determined that 
harassment in the form of behavioral disturbance may occur.
    The proposed survey would use air gun sources composed of two 2400 
in\3\ air guns, a single 440 in\3\ air gun, and a single 10 in\3\ air 
gun. Safety and disturbance radii for the sound levels produced by the 
planned air gun configurations and pinger were estimated for the 2012 
IHA issued for Area 1; however, distances to the 190, 180, and 160 dB 
thresholds were measured in late April 2012 (see Table 1) and would be 
used for mitigation purposes during the seismic survey activities until 
the results from the 2013 SSV study are available.

  Table 1--Distances to Sound Thresholds for Monitoring and Mitigation
------------------------------------------------------------------------
            Source                 190 dB        180 dB        160 dB
------------------------------------------------------------------------
Pinger........................  1 m           3 m           25 m
10 cui air gun................  10 m          33 m          330 m
440 cui air gun...............  NA            NA            NA
2,400 cui air gun (nearshore).  380 m         1400 m        9500 m
2,400 cui air gun (offshore)..  290 m         910 m         8700 m
------------------------------------------------------------------------

    In addition to the marine mammal monitoring radii described above, 
pursuant to Alaska Department of Fish and Game restrictions, there 
would be a 1.6 km setback of sound source points from the mouths of any 
anadromous streams.
    Apache also plans to use dedicated vessels to deploy and retrieve 
the nodal recording system. Sounds produced by those vessels are not 
expected to exceed 180 dB (rms). Therefore, mitigation related to 
acoustic impacts from these activities is not required.

(3) Speed and Course Alterations

    If a marine mammal is detected outside the applicable safety radius 
and, based on its position and the relative motion, is likely to enter 
the safety radius, changes of the vessel's speed and/or direct course 
will be considered if this does not compromise operational safety. For 
marine seismic surveys using large arrays, course alterations are not 
typically possible. However, for the smaller air gun arrays planned 
during the proposed site surveys, such changes may be possible. After 
any such speed and/or course alteration is begun, the marine mammal 
activities and movements relative to the survey vessel will be closely 
monitored to ensure that the marine mammal does not approach within the 
safety radius. If the mammal appears likely to enter the safety radius, 
further mitigative actions will be taken, including a power down or 
shut down of the air gun(s).

(4) Power-Downs

    A power-down for mitigation purposes is the immediate reduction in 
the number of operating air guns such that the radii of the 190 dB rms 
and 180 dB rms zones are decreased to the extent that an observed 
marine mammal(s) are not in the applicable safety zone of the full 
array. During a power-down, one ``mitigation'' air gun, typically the 
10 in\3\, continues firing. Operation of the 10 in\3\ air gun decreases 
the safety radii to 10 m, 33 m, and 330 m for the 190 dB, 180 dB, and 
160 dB, respectively. The continued operation of one air gun is 
intended to (a) alert marine mammals to the presence of the survey 
vessel in the area, and (b) retain the option of initiating a ramp up 
to full operations under poor visibility conditions.
    The array will be immediately powered down whenever a marine mammal 
is sighted approaching close to or within the applicable safety zone of 
the full array, but is outside the applicable safety zone of the single 
mitigation air gun. Likewise, if a mammal is already within the safety 
zone when first detected, the air guns will be powered down 
immediately. If a marine mammal is sighted within or about to enter the 
applicable safety zone of the single mitigation air gun, it too will be 
shut down (see following section).
    Following a power-down, operation of the full air gun array would 
not resume until the marine mammal has cleared the safety zone. The 
animal would be considered to have cleared the safety zone if it:
     Is visually observed to have left the safety zone of the 
full array, or
     Has not been seen within the zone for 15 min in the case 
of pinnipeds or small odontocetes, or
     Has not been seen within the zone for 30 min in the case 
of large odontocetes.

(5) Shut-Downs

    The operating air gun(s) will be shut down completely if a marine 
mammal approaches or enters the safety radius and a power-down is not 
practical or adequate to reduce exposure to less than 190 or 180 dB 
rms, as appropriate. In most cases, this means the mitigation air gun 
will be shut down completely if a marine mammal approaches or enters 
the estimated safety radius around the single 10 in\3\ air gun while it 
is operating during a power down. Air gun activity will not resume 
until the marine mammal has cleared the safety radius. The animal would 
be considered to have cleared the safety radius as described above 
under power down procedures.

(6) Ramp-Ups

    A ramp-up of an air gun array provides a gradual increase in sound 
levels, and involves a step-wise increase in the number and total 
volume of air guns firing until the full volume is achieved. The 
purpose of a ramp-up (or ``soft start'') is to ``warn'' cetaceans and 
pinnipeds in the vicinity of the air guns and to provide the time for 
them to leave the area and thus avoid any potential injury or 
impairment of their hearing abilities.
    During the proposed seismic survey, the seismic operator will ramp 
up the air gun array slowly. NMFS requires the rate of ramp-up to be no 
more than 6 dB per 5-minute period. Ramp-up is used at the start of air 
gun operations, after a power- or shut-down, and after any period of 
greater than 10 minutes in duration without air gun operations (i.e., 
extended shutdown).
    A full ramp-up after a shut down will not begin until there has 
been a

[[Page 12733]]

minimum of 30 minutes of observation of the safety zone by PSOs to 
assure that no marine mammals are present. The entire safety zone must 
be visible during the 30-minute lead-in to a full ramp up. If the 
entire safety zone is not visible, then ramp-up from a cold start 
cannot begin. If a marine mammal(s) is sighted within the safety zone 
during the 30-minute watch prior to ramp-up, ramp- up will be delayed 
until the marine mammal(s) is sighted outside of the safety zone or the 
animal(s) is not sighted for at least 15-30 minutes: 15 minutes for 
small odontocetes and pinnipeds (e.g. harbor porpoises, harbor seals, 
and Steller sea lions), or 30 minutes for large odontocetes (e.g., 
killer whales and beluga whales).

(7) Shut-downs for Aggregations of Whales, Harbor Porpoises, and Beluga 
Cow-Calf Pairs

    The following additional protective measures beluga whale cow-calf 
pairs and aggregations of whales and harbor porpoises are required. 
Specifically, a 160-dB vessel monitoring zone would be established and 
monitored in Cook Inlet during all seismic surveys. Whenever an 
aggregation of beluga whales, killer whales, or harbor porpoises (five 
or more animals of any age/sex class), or any beluga whale cow-calf 
pairs are observed approaching the 160-dB safety zone around the survey 
operations, the survey activity would not commence or would shut down, 
until they are no longer present within the 160-dB safety zone of 
seismic surveying operations.

Additional Mitigation Measures Proposed by NMFS

    In addition to the mitigation measures discussed above, NMFS 
requires the following protective measures:
    (1) All vessels should reduce speed when within 300 yards (274 m) 
of whales, and those vessels capable of steering around such groups 
should do so. Vessels may not be operated in such a way as to separate 
members of a group of whales from other members of the group;
    (2) Avoid multiple changes in direction and speed when within 300 
yards (274 m) of whales; and
    (3) When weather conditions require, such as when visibility drops, 
support vessels must adjust speed (increase or decrease) and direction 
accordingly to avoid the likelihood of injury to whales.
    (4) When aggregations of five or more harbor porpoises are observed 
approaching the 160 dB zone around survey operations, the survey 
activity will not commence or will shut down, until they are no longer 
present within the 160 dB zone. (This was recommended in a comment from 
the Commission).
    (5) Apache must immediately report to NMFS if 25 beluga whales are 
detected in the disturbance zone. If the number of detected takes is 
meets or exceeds the amount authorized for any marine mammal species, 
Apache must immediately cease survey operations involving the use of 
active sound sources (e.g., air guns and pingers) and notify NMFS.
    (6) Apache must not operate air guns within 10 miles (16 km) of the 
mean higher high water (MHHW) line of the Susitna Delta (Beluga River 
to the Little Susitna River) between mid-April and mid-October (to 
avoid any effects to belugas in an important feeding and potential 
breeding area).
    (7) Safety and weather permitting, aerial surveys shall be 
conducted on a daily basis when there are any seismic-related 
activities (including but not limited to node laying/retrieval or 
airgun operations) occurring north or east of a line from Tyonek across 
to the eastern side of Number 3 Bay of the Captain Cook State 
Recreation Area, Cook Inlet (roughly the southern-most point of Corps 
defined Region 9). Surveys are to be flown even if the air guns are not 
being fired.

Mitigation Measures Considered but Not Required

    NMFS considered whether time/area restrictions were warranted. 
Mirroring a requirement in the Incidental Take Statement for the 
related Biological Opinion, NMFS has included an exclusion zone that 
extends 10 miles (16 km) from the mean higher high water (MHHW) line of 
the Susitna Delta (Beluga River to the Little Susitna River) to avoid 
impacts to beluga in an important feeding and potential breeding area. 
Between mid-April and mid-October, air guns may not be operated within 
the exclusion zone. NMFS determined that such restrictions are not 
necessary or practicable elsewhere in the 2013 survey area. Beluga 
whales remain in Cook Inlet year-round, but demonstrate seasonal 
movement within the Inlet; in the summer and fall, they concentrate in 
upper Cook Inlet's rivers and bays, but tend to disperse offshore and 
move to mid-Inlet in winter (Hobbs et al., 2005). The available 
information indicates that in the winter months belugas are dispersed 
in deeper waters in mid-Inlet past Kalgin Island, with occasional 
forays into the upper inlet, including the upper ends of Knik and 
Turnagain Arms. Their winter distribution does not appear to be 
associated with river mouths, as it is during the warmer months. The 
spatial dispersal and diversity of winter prey are likely to influence 
the wider beluga winter range throughout the mid-Inlet. Apache now 
expects to mobilize crews and equipment for its seismic survey in 
February 2013, which would coincide with the time of year when belugas 
are dispersed offshore in the mid-Inlet and away from river mouths. In 
the spring, when survey operations are expected to start, beluga whales 
are regularly sighted in the upper Inlet beginning in late April or 
early May, coinciding with eulachon runs in the Susitna River and 
Twenty Mile River in Turnagain Arm. Therefore, NMFS believes that the 
timing and location of the seismic survey, with the exclusion zone 
around the Susitna Delta, will avoid areas and seasons that overlap 
with important beluga whale behavioral patterns.
    NMFS also considered whether to require time area restrictions for 
areas identified as home ranges during August through March for 14 
satellite-tracked beluga whales in Hobbs et al., 2005. NMFS has 
determined not to require time/area restrictions for these areas within 
the phase 2 survey area. The areas in question within phase 2 are 
relatively large areas in which belugas are dispersed. In addition, 
data for 14 tracked belugas does not establish that belugas will not 
appear in other areas--particularly during the periods of the year when 
belugas are more dispersed in Cook Inlet. Time/area restrictions for 
these areas thus would not yield a material benefit for the species. 
Such restrictions also are not practicable given the applicant's need 
to survey the areas in question and the need for operational 
flexibility given weather conditions, real-time adjustment of 
operations to avoid marine mammals and other factors. The suite of 
other mitigation and monitoring measures will still apply.

Mitigation Conclusions

    NMFS has carefully evaluated the applicant's proposed mitigation 
measures and considered a range of other measures in the context of 
ensuring that NMFS prescribes the means of effecting the least 
practicable impact on the affected marine mammal species and stocks and 
their habitat. Our evaluation of potential measures included 
consideration of the following factors in relation to one another:
     The manner in which, and the degree to which, the 
successful implementation of the measure is expected to minimize 
adverse impacts to marine mammals;

[[Page 12734]]

     The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned; and
     The practicability of the measure for applicant 
implementation.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered, NMFS has determined that the 
mitigation measures provide the means of effecting the least 
practicable impact on marine mammal species or stocks and their 
habitat, paying particular attention to rookeries, mating grounds, and 
areas of similar significance.

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 ITAs 
must include the suggested means of accomplishing the necessary 
monitoring and reporting that will result in increased knowledge of the 
species and of the level of taking or impacts on populations of marine 
mammals that are expected to be present in the proposed action area.

Summary of 2012 Monitoring and Mitigation

    Marine mammal monitoring was conducted in central Cook Inlet 
between May 6 and September 30, 2012, which resulted in a total of 
6,912 hours of observations. Monitoring was conducted from the two 
seismic survey vessels, a mitigation vessel, four land platforms, and 
an aerial platform (either a helicopter or small fixed wing aircraft). 
PSOs monitored from the seismic vessels, mitigation vessel, and land 
platforms during all daytime seismic operations. Aerial overflights 
were conducted 1-2 times daily over the survey area and surrounding 
coastline, including the major river mouths, to monitor for larger 
concentrations of marine mammals in and around the survey site. Passive 
acoustic monitoring (PAM) took place from the mitigation vessel during 
all night time seismic survey operations and most daytime seismic 
survey operations. During the entire 2012 survey season, Apache's PAM 
equipment yielded only six confirmed marine mammal detections, one of 
which was a Cook Inlet beluga whale. The single Cook Inlet beluga whale 
detection did not, however, result in a shutdown procedure.
    Six identified species and three unidentified species of marine 
mammals were observed from the vessel, land, and aerial platforms 
between May 6 and September 30, 2012. The species observed included 
Cook Inlet beluga whales, harbor seals, harbor porpoises, Steller sea 
lion, gray whale, and California sea lions. PSOs also observed 
unidentified species including a large cetacean, pinniped, and marine 
mammal. The gray whale and California sea lion were not included in the 
2012 IHA, so mitigation measures were implemented for these species to 
prevent unauthorized takes. There were a total of 882 sightings and an 
estimated 5,232 individuals (the number or individuals is typically 
higher than the number of sightings because a single sighting may 
consist of multiple individuals). Harbor seals were the most frequently 
observed marine mammal at 563 sightings (~3,471 individuals), followed 
by beluga whales with 151 sightings (~1,463 individuals), harbor 
porpoises with 137 (~190 individuals), and gray whales with 9 sightings 
(9 individuals). Steller sea lions were observed on three separate 
occasions (~4 individuals) and California sea lions were observed once 
(~2 individuals). No killer whales were observed during seismic survey 
operations conducted under the 2012 IHA.
    A total of 88 safety zone clearing delays, 154 shut downs, 7 power 
downs, 23 shut downs followed by a power down, and 1 speed and course 
alteration occurred under the 2012 IHA. Safety zone clearing delays, 
shut downs, and shut downs followed by a power down occurred most 
frequently during harbor seal sightings (n=61, n=110, n=14, 
respectively), followed by harbor porpoise sightings (n=18, n=28, n=6, 
respectively), and then beluga whale sightings (n=5, n=6, n=3, 
respectively). Power downs occurred most frequently with harbor seal 
(n=3) and harbor porpoise (n=3) sightings. One speed and course 
alteration occurred in response to a beluga whale sighting. A total of 
17 Level B harassment takes were detected from May 6 to September 30, 
2012, including harbor porpoise (n=4) and harbor seals (n=13). No other 
marine mammal species were detected in the Level B harassment zone. 
There were no detected Level A harassment takes of either cetaceans or 
pinnipeds during the 2012 seismic survey.

Monitoring Measures

    Apache will provide marine mammal monitoring to implement the 
mitigation measures that require real-time monitoring.
(1) Visual Vessel-Based Monitoring
    Vessel-based monitoring for marine mammals will be done by 
experienced PSOs throughout the period of marine survey activities. 
PSOs will monitor the occurrence and behavior of marine mammals near 
the survey vessel during all daylight periods during operation and 
during most daylight periods when air gun operations are not occurring. 
PSO duties will include watching for and identifying marine mammals, 
recording their numbers, distances, and reactions to the survey 
operations, and documenting take.
    A sufficient number of PSOs will be required onboard the survey 
vessel to meet the following criteria: (1) 100 percent monitoring 
coverage during all periods of survey operations in daylight; (2) 
maximum of 4 consecutive hours on watch per PSO; and (3) maximum of 12 
hours of watch time per day per PSO.
    PSO teams will consist of experienced field biologists. An 
experienced field crew leader will supervise the PSO team onboard the 
survey vessel. Apache currently plans to have PSOs aboard the three 
vessels: the two source vessels (M/V Peregrine Falcon and M/V Arctic 
Wolf) and one support vessel (M/V Dreamcatcher). Two PSOs will be on 
the source vessels and two PSOs will be on the support vessel to 
observe the safety, power down, and shut down areas. The vessel-based 
observers will watch for marine mammals during all periods when sound 
sources are in operation and for a minimum of 30 minutes prior to the 
start of air gun or pinger operations after an extended shut down.
    Crew leaders and most other biologists serving as observers will be 
individuals with experience as observers during seismic surveys in 
Alaska or other areas in recent years.
    The observer(s) will watch for marine mammals from the best 
available vantage point on the source and support vessels, typically 
the flying bridge. The observer(s) will scan systematically with the 
unaided eye and 7x50 reticle binoculars. Laser range finders will be 
available to assist with estimating distance. Personnel on the bridge 
would assist the observer(s) in watching for marine mammals.
    All observations will be recorded in a standardized format. Data 
would be entered into a custom database using a notebook computer. The 
accuracy of the data will be verified by computerized validity data 
checks as the data are entered and by subsequent manual checks of the 
database. These procedures will allow for initial summaries of the data 
to be prepared during and shortly after the completion of the field 
program, and will facilitate transfer of the data to statistical, 
geographical, or other programs for

[[Page 12735]]

future processing and achieving. When a mammal sighting is made, the 
following information about the sighting will be recorded:
    (A) Species, group size, age/size/sex categories (if determinable), 
behavior when first sighted and after initial sighting, heading (if 
consistent), bearing and distance from the PSO, apparent reaction to 
activities (e.g., none, avoidance, approach, paralleling, etc.), 
closest point of approach, and behavioral pace;
    (B) Time, location, speed, activity of the vessel, sea state, ice 
cover, visibility, and sun glare; and
    (C) The positions of other vessel(s) in the vicinity of the PSO 
location.
    The ship's position, speed of support vessels, and water 
temperature, water depth, sea state, ice cover, visibility, and sun 
glare will also be recorded at the start and end of each observation 
watch, every 30 minutes during a watch, and whenever there is a change 
in any of those variables.
(2) Visual Shore-Based Monitoring
    In addition to the vessel-based PSOs, Apache will utilize a shore-
based station to visually monitor for marine mammals. The shore-based 
station will follow all safety procedures, including bear safety. The 
location of the shore-based station will need to be sufficiently high 
to observe marine mammals; the PSOs will be equipped with pedestal 
mounted ``big eye'' (20x110) binoculars. The shore-based PSOs will scan 
the area prior to, during, and after the air gun operations, and will 
be in contact with the vessel-based PSOs via radio to communicate 
sightings of marine mammals approaching or within the project area.
(3) Aerial-Based Monitoring
    When survey operations occur near a river mouth, Apache will 
utilize the crew helicopter or a small fixed-wing aircraft to conduct 
aerial surveys near river mouths prior to the commencement of air gun 
operations in order to identify locations where beluga whales 
congregate. In addition, aerial surveys shall be conducted on a daily 
basis (weather and safety permitting) when there are any seismic-
related activities (including but not limited to node laying/retrieval 
or air gun operations) occurring north or east of a line from Tyonek 
across to the eastern side of Number 3 Bay of the Captain Cook State 
Recreation Area, Cook Inlet (roughly the southern-most point of Corps 
defined Region 9). Surveys are to be flown even if the air guns are not 
being fired. The types of helicopters currently planned for use by 
Apache include a Bell 407, Bell UH1B, and ASB3. A twin-engine Islander, 
or similar fixed-wing aircraft, may also be used to conduct aerial 
surveys in lieu of helicopter. Weather and safety permitting, aerial 
surveys will fly at an altitude of 305 m (1,000 ft). In the event of a 
marine mammal sighting, aircraft will attempt to maintain a radial 
distance of 457 m (1,500 ft) from the marine mammal(s). Aircraft will 
avoid approaching marine mammals from head-on, flying over or passing 
the shadow of the aircraft over the marine mammal(s). By following 
these operational requirements, sound levels underwater are not 
expected to meet or exceed NMFS harassment thresholds (Richardson et 
al., 1995; Blackwell et al., 2002).
    Based on data collected from Apache during its survey operations 
conducted under the April 2012 IHA, NMFS believes that the foregoing 
monitoring measures will allow Apache to identify animals nearing or 
entering the 160 dB zone with a reasonably high degree of 
effectiveness.

Reporting Measures

(1) Weekly Field Reports
    During the proposed survey, the PSOs will prepare a report each day 
summarizing the recent results of the monitoring program. The field 
reports will summarize the species and numbers of marine mammals 
sighted. These reports will be provided to NMFS and to the survey 
operators on a weekly basis. At the end of each month, a summary of the 
weekly reports will be submitted to NMFS.
(2) Technical Report
    The results of Apache's 2013 monitoring program, including 
estimates of ``take'' by harassment (based on presence in the 160 dB 
harassment zone), will be presented in the ``90-day'' and Final 
Technical reports. The Technical Report will include:
    (a) Summaries of monitoring effort (e.g., total hours, total 
distances, and marine mammal distribution through the study period, 
accounting for sea state and other factors affecting visibility and 
detectability of marine mammals);
    (b) Analyses of the effects of various factors influencing 
detectability of marine mammals (e.g., sea state, number of observers, 
and fog/glare);
    (c) Species composition, occurrence, and distribution of marine 
mammal sightings, including date, water depth, numbers, age/size/gender 
categories (if determinable), group sizes, and ice cover;
    (d) Analyses of the effects of survey operations;
     Sighting rates of marine mammals during periods with and 
without seismic survey activities (and other variables that could 
affect detectability), such as:
     Initial sighting distances versus survey activity state;
     Closest point of approach versus survey activity state;
     Observed behaviors and types of movements versus survey 
activity state;
     Numbers of sightings/individuals seen versus survey 
activity state;
     Distribution around the source vessels versus survey 
activity state; and
     Estimates of take by harassment based on presence in the 
160 dB disturbance zone.
(3) Comprehensive Report
    Following the survey season, a comprehensive report describing the 
vessel-based, shore-based, and aerial-based monitoring programs will be 
prepared. The comprehensive report will describe the methods, results, 
conclusions and limitations of each of the individual data sets in 
detail. The report will also integrate (to the extent possible) the 
studies into a broad based assessment of industry activities, and other 
activities that occur in Cook Inlet, and their impacts on marine 
mammals. The report will help to establish long-term data sets that can 
assist with the evaluation of changes in the Cook Inlet ecosystem. The 
report will attempt to provide a regional synthesis of available data 
on industry activity in this part of Alaska that may influence marine 
mammal density, distribution and behavior.
(4) Notification of Injured or Dead Marine Mammals
    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), Apache will 
immediately cease the specified activities and immediately report the 
incident to the Chief of the Permits and Conservation Division, Office 
of Protected Resources, NMFS, and the Alaska Regional Stranding 
Coordinators. The report will 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;

[[Page 12736]]

     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 will not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS will work with Apache to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. Apache will not be able to 
resume their activities until notified by NMFS via letter, email, or 
telephone.
    In the event that Apache 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), 
Apache will immediately report the incident to the Chief of the Permits 
and Conservation Division, Office of Protected Resources, NMFS, and the 
NMFS Alaska Stranding Hotline and/or by email to the Alaska Regional 
Stranding Coordinators. The report will include the same information 
identified in the paragraph above. Activities will be able to continue 
while NMFS reviews the circumstances of the incident. NMFS will work 
with Apache to determine whether modifications in the activities are 
appropriate.
    In the event that Apache 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), Apache will report the incident to 
the Chief of the Permits and Conservation Division, Office of Protected 
Resources, NMFS, and the NMFS Alaska Stranding Hotline and/or by email 
to the Alaska Regional Stranding Coordinators, within 24 hours of the 
discovery. Apache would 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 of Marine Mammals

    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 behavioral 
harassment is anticipated as a result of the proposed marine survey. 
Anticipated impacts to marine mammals are associated with noise 
propagation from the sound sources (e.g., air guns and pingers) used in 
the seismic survey; no take is expected to result from the detonation 
of explosives onshore, as supported by the SSV study, or from vessel 
strikes.
    Apache requests authorization to take five marine mammal species by 
Level B harassment. These five marine mammal species are: Cook Inlet 
beluga whale (Delphinapterus leucas); killer whale (Orcinus orca); 
harbor porpoise (Phocoena phocoena); harbor seal (Phoca vitulina 
richardsi), and Steller sea lion (Eumetopias jubatus).
    The full suite of potential impacts to marine mammals was described 
in detail in the Potential Effects of the Specified Activity on Marine 
Mammals section found earlier in this document and in the notice of the 
proposed IHA (77 FR 73434, December 10, 2012). The potential effects of 
sound from the proposed seismic survey might include one or more of the 
following: tolerance; masking of natural sounds; behavioral 
disturbance; non-auditory physical effects; and, at least in theory, 
temporary or permanent hearing impairment (Richardson et al. 1995). The 
most common and likely impact would be from behavioral disturbance, 
including avoidance of the ensonified area or changes in speed, 
direction, and/or diving profile of the animal. Hearing impairment (TTS 
and PTS) are highly unlikely to occur based on the required mitigation 
and monitoring measures that would preclude marine mammals being 
exposed to noise levels high enough to cause hearing impairment.
    For impulse sounds, such as those produced by air gun(s) and 
pingers used in the seismic survey, NMFS uses a received level of 160 
dBrms re 1 [mu]Pa to indicate the onset of Level B 
harassment. However, not all animals react to sounds at this level, and 
many will not show strong reactions (and in some cases any reaction) 
until sounds are stronger. 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)). Tables 7, 
9, and 11 in Southall et al. (2007) outline the numbers of low-
frequency cetaceans, mid-frequency cetaceans, and pinnipeds in water, 
respectively, reported as having behavioral responses to multi-pulses 
in 10-dB received level increments. These tables illustrate that 
although some studies have found moderate responses at these levels, 
some show that more severe reactions did not occur until sounds were 
much higher than 160 dBrms re 1[mu]Pa, while some also show 
reactions to sounds lower than 160 dBrms re 1 [mu]Pa. 
However, Tables 9 and 11 for mid-frequency cetaceans and pinnipeds, 
respectively, do not report significant reactions to multiple pulse 
sounds below 160 dB, except one study involving whales in the Beaufort 
Sea--a less industrialized and sparsely populated area compared to Cook 
Inlet. Beluga whales in that area are not as experienced with the types 
and variety of sound sources as the belugas in Cook Inlet.
    To estimate take by Level B harassment, Apache provided 
calculations for the 160-dB isopleths and then overlaid those isopleths 
with the density of marine mammals in the total area ensonified within 
those isopleths over the time of the surveys. Apache provided a full 
description of the methodology used to estimate takes by harassment in 
its IHA application (see ADDRESSES), which is also provided in the 
following sections. Following the publication of the Federal Register 
notice of the proposed IHA for Area 2, NMFS asked Apache to apply a 
correction factor to take estimates for beluga whales in its analysis 
(Hobbs et al., 2000). After receiving the new information from Apache, 
NMFS sent the updated density estimates to beluga whale experts at 
NOAA's National Marine Mammal Laboratory (NMML) for their review. NMML 
directed NMFS to a published habitat model developed for Cook Inlet 
beluga whales that was not considered by Apache and provides densities 
throughout the inlet based on the data from aerial surveys (Goetz et 
al., 2012). NMML agreed to conduct an analysis that would apply the 
habitat-based model to Apache's seismic survey for the purpose of 
estimating beluga whale densities and takes. The results of NMML's 
analysis using the habitat-based model are provided below.

Basis for Estimating ``Take by Harassment''

    As stated previously, it is current NMFS policy to estimate take by 
Level B harassment for impulse sounds at a received level of 160 
dBrms re 1[mu]Pa. As

[[Page 12737]]

described earlier in this notice, impulsive sounds would be generated 
by air gun arrays that would be used to obtain geological data during 
the surveys. To estimate potential takes by Level B harassment in this 
application, as well as for mitigation radii to be implemented by PSOs, 
ranges to the 160 dBrms re 1 [mu]Pa isopleths were estimated 
at three different water depths (5 m, 25 m, and 45 m) for nearshore 
surveys and at 80 m for channel surveys (Tables 2 and 3).

                          Table 2--Distances to Sound Thresholds for Nearshore Surveys
----------------------------------------------------------------------------------------------------------------
                                                                                                    Distance in
                                                  Water depth at    Distance in     Distance in    the parallel
           Threshold (dB re 1 [mu]Pa)                 source        the onshore    the offshore      to shore
                                                   location (m)   direction (km)  direction (km)  direction (km)
----------------------------------------------------------------------------------------------------------------
160.............................................               5            0.85            3.91            1.48
                                                              25            4.70            6.41            6.34
                                                              45            5.57            4.91            6.10
----------------------------------------------------------------------------------------------------------------
180.............................................               5            0.46            0.60            0.54
                                                              25            1.06            1.07            1.42
                                                              45            0.70            0.83            0.89
----------------------------------------------------------------------------------------------------------------
190.............................................               5            0.28            0.33            0.33
                                                              25            0.35            0.36            0.44
                                                              45            0.10            0.10            0.51
----------------------------------------------------------------------------------------------------------------


                         Table 3--Distances to Sound Thresholds for the Channel Surveys
----------------------------------------------------------------------------------------------------------------
                                                             Water depth at    Distance in the   Distance in the
                Threshold (dB re 1 [mu]Pa)                   source location      broadside          endfire
                                                                   (m)         direction (km)    direction (km)
----------------------------------------------------------------------------------------------------------------
160.......................................................                80              4.24              4.89
180.......................................................                80              0.91              0.98
190.......................................................                80              0.15              0.18
----------------------------------------------------------------------------------------------------------------


        Table 4--Areas Ensonified to 160 dB for Nearshore Surveys
------------------------------------------------------------------------
      Nearshore survey depth                           Area ensonifed to
          classification             Depth range (m)     160 dB (km\2\)
------------------------------------------------------------------------
Shallow...........................               5-21                346
Mid-Depth.........................              21-38                458
Deep..............................              38-54                455
------------------------------------------------------------------------

    The areas ensonified to the 160 dB isopleth for the nearshore 
survey are provided in Table 4. The area ensonifed to the 160 dB 
isopleth for the channel survey is 389 km\2\.
    The notice of the proposed IHA (77 FR 73434, December 10, 2012) 
describes Apache's estimated densities of marine mammals that may occur 
in the areas where activities are planned, and areas of water that may 
be ensonified by pulsed sounds to >=160 dB. The following paragraphs 
provide information regarding Apache's approach to correcting the 
density estimates for Cook Inlet beluga whales, NMML's review of the 
corrected densities and recommendations, and NMFS revised estimates of 
beluga whale densities and take estimates based on NMML's habitat-based 
model.
    Marine mammal densities near the planned activities in Cook Inlet 
were estimated from the annual aerial surveys conducted by NMFS between 
2000 and 2011 for Cook Inlet beluga whales (Rugh et al., 2000, 2001, 
2002, 2003, 2004, 2005, 2006, 2007; Shelden et al., 2008, 2009, 2010; 
Hobbs et al., 2011). These surveys are flown in June to collect 
abundance data for beluga whales, but sightings of other marine mammals 
are also reported. Although these data are only collected in one month 
each year, these surveys provide the best available relatively long-
term data set for sighting information in the proposed action area, but 
do not correct for missed whales or account for seasonal variations in 
distribution or habitat use of each species. To correct for missed 
whales, Apache applied the correction factor of 1.015 (CV= 3%) for the 
years 1994 to 1998 and 1.021 (CV=1%) for the years 1999 and 2000, which 
was applied in Hobbs et al. (2000). In the subsequent annual aerial 
survey reports (2001 to 2011), the authors state that the correction 
factors are within the range for 1999 and 2000. Therefore, Apache 
applied the correction factor of 1.021 to all of the highest number of 
sightings for each year and calculated the densities and takes the same 
as the previous IHA.
    After receiving the new information from Apache, NMFS sent the 
updated density estimates to beluga whale experts at NMML for their 
review. NMML staff indicated that Apache's calculations appeared to 
account for both on and off effort flight hours (instead of just on-
effort hours) and had not included 1,810 km of coastline. NMML 
attempted to correct Apache's calculations by including on-effort 
survey hours and 1,810 km of coastline, but the resulting take 
calculations for beluga whales were grossly inaccurate and unreliable. 
NMML staff directed NMFS to a published habitat model developed for 
Cook Inlet beluga whales that provides densities throughout the inlet 
based on the data from aerial surveys (Goetz et al., 2012). Moreover, 
NMML staff agreed to conduct an

[[Page 12738]]

independent analysis that would apply the habitat-based model to 
Apache's seismic survey for the purpose of estimating beluga whale 
densities and takes. Additional information on the habitat-based model 
is provided in Goetz et al., (2012). A summary of the habitat-based 
model and the results of NMML's analysis are provided below.
    NMML developed a predictive habitat model from the distribution and 
group size of beluga whales observed between 1994 and 2008. A 2-part 
``hurdle'' model (a hurdle model is a modified count model in which 
there are two processes, one generating the zeros and one generating 
the positive values) was applied to describe the physical and 
anthropogenic factors that influence (1) beluga presence (mixed model 
logistic regression) and (2) beluga count data (mixed model Poisson 
regression). Beluga presence was negatively associated with sources of 
anthropogenic disturbance and positively associated with fish 
availability and access to tidal flats and sandy substrates. Beluga 
group size was positively associated with tidal flats and proxies for 
seasonally available fish. Using this analysis, Goetz et al. (2012) 
produced habitat maps for beluga presence, group size, and the expected 
number of belugas in each 1 km\2\ cell of Cook Inlet.
    The habitat-based model developed by NMML uses a Geographic 
Information System (GIS). A GIS is a computer system capable of 
capturing, storing, analyzing, and displaying geographically referenced 
information; that is, data identified according to location. NMML 
created a digital representations of Apache's actual anticipated 2013 
marine survey area (called a shapefile), which included a 9.5 km 
``buffer'' to represent the approximate distance from the sound source 
to the 160 dB isopleth. This is a smaller portion of Area 2, where 
Apache plans on conducting operations during the 2013 survey. When NMML 
staff applied their model of beluga density estimates to the 2013 
survey area, they estimated that at a total of 21.5 belugas could taken 
by Level B harassment (Figure 1). This estimate assumed a ``snap shot'' 
survey (i.e., that the entire survey area would be ensonified at once 
rather than the sum of multiple track lines). In reality, the entire 
area will not be completely ensonfied at once, and most of the survey 
will occur where beluga density is extremely low or zero based on the 
NMML habitat model. Calculating a take or exposure level for each 
transect line separately and adding those up over the survey period 
will likely be lower (or not significantly different) than if one 
assumes the entire area is ensonfied at one time, particularly since 
the operation will only be at the ``edges'' for a short time where the 
beluga densities are highest and almost all of the estimate take occurs 
based on NMML's calculation. For this and other reasons explained in 
the notice, we believe 21.5 (22) takes is a reasonable estimate for the 
survey.
BILLING CODE 3510-22-P

[[Page 12739]]

[GRAPHIC] [TIFF OMITTED] TN25FE13.000

BILLING CODE 3510-22-C

           Table 5--Summary of Apache's Marine Mammal Densities
------------------------------------------------------------------------
                                                      Density (number/
                                                           km\2\)
                      Species                      ---------------------
                                                     Maximum    Average
------------------------------------------------------------------------
Harbor seal (total number observed)...............    0.00644    0.00317
Harbor porpoise (total number observed)...........    0.00179    0.00006
Killer whale (total number observed)..............    0.00011    0.00001
Steller sea lion (total number observed)..........    0.00035    0.00011
------------------------------------------------------------------------


[[Page 12740]]

    Fifteen species of marine mammals are known to occur in Cook Inlet, 
but Apache only request takes by Level B harassment of five (Cook Inlet 
beluga whales, killer whales, harbor porpoises, harbor seals, and 
Steller sea lions) that are most likely to be encountered during the 
proposed survey. Two of the five species (Cook Inlet beluga whales and 
western population of Steller sea lions) are listed as endangered under 
the ESA.

Potential Number of Takes by Harassment

    This subsection provides estimates of the number of individuals 
potentially exposed to sound levels >= 160 dBrms re 1 [mu]Pa 
during seismic survey operations. Except for Cook Inlet beluga whales, 
the estimates were calculated by multiplying the expected densities by 
the anticipated area ensonified by levels >= 160 dBrms re 1 
[mu]Pa by the number of expected days that will be subject to seismic 
survey activities in the action area. As discussed above, NMML's 
analysis multiplied beluga whale densities from their habitat-based 
model by the entire 2013 survey area within Area 2. According to 
section 2 in Apache's IHA application, a survey crew will collect 
seismic data 10-12 hours per day over approximately 160 days over the 
course of 8 to 9 months. Apache assumes that over the course of these 
160 days, 100 days would be working in the offshore region and 60 days 
would be working in the shallow, intermediate, and deep nearshore 
region. Of those 60 days in the nearshore region, 20 days would be 
spent working in each of the three depths. It is important to note that 
environmental conditions (such as ice, wind, and fog) will play a 
significant role in the actual number of operating days; therefore, 
these are considered over estimates.
    Except for Cook Inlet beluga whales, the number of estimated takes 
by Level B harassment was calculated using the following assumptions:
     The number of nearshore and shallow water survey days is 
20 and daily acoustic footprint is 356 km\2\.
     The number of nearshore and intermediate water depth 
survey days is 20 and daily acoustic footprint is 468 km\2\.
     The number of nearshore and deep water depth survey days 
is 20 days and daily acoustic footprint is 455 km\2\.
     The number of offshore survey days is 100 and daily 
acoustic footprint is 389 km\2\.
    The probability of sightings for harbor seals and Steller sea lions 
is higher than what is anticipated because there are no haul-out sites 
within the action area. These density estimates are skewed by the 
numbers observed in large haul outs during aerial surveys. Seals in the 
water usually travel in small groups or as single individuals; 
therefore, although Table 3 indicates an average of 204 and maximum of 
414 seals to be observed, it is highly unlikely that those number of 
seals will actually be taken by harassment during the proposed seismic 
survey.
    Similarly, the number of actual takes by Level B harassment of 
Steller sea lions is expected to be much lower than the average of 
seven and maximum of 22. During the NMFS aerial surveys, no Steller sea 
lions were observed in upper Cook Inlet. Less than five Steller sea 
lions have been observed by the Port of Anchorage monitoring program, 
and those observed have been juvenile animals (likely male). According 
to Apache's final report submitted under the 2012 IHA, only four 
Steller sea lions were observed during seismic survey operations 
conducted between May 6 and September 30, 2012. Therefore, Apache 
anticipates that there will be less than five Steller sea lions in the 
proposed action area during the effective period of the IHA.
    The average and maximum observations for harbor porpoise and killer 
whales shown in Table 6 appear to be reasonable based on the NMFS 
aerial surveys, although the actual number of animals is expected to be 
low.
    The NMML analysis found that a total of 21.5 Cook Inlet beluga 
whales in the 2013 survey area within Area 2 could be taken by Level B 
harassment over the course of the seismic survey. NMFS recognizes that 
the NMML analysis has limitations, including calculating take based on 
the expected project area rather than on a transect-by-transect basis, 
relying on data from the June beluga surveys, and not accounting for 
the fact that operations shut down if animals are observed within or 
approaching the 180 dB safety zone. However, estimating the number of 
belugas that actually will be exposed to 160 dB is difficult and 
imprecise by nature and NMFS believes that the NMML estimate is 
reasonably accurate. In addition, it is important to note that a 
combination of factors--including extensive visual and acoustic 
monitoring used throughout this project, particularly for sighting 
beluga whales approaching the area--are expected to result in the 
actual number of takes being no higher than (and likely, much lower 
than) the NMML estimates. Furthermore, based on the time it took to 
complete the previous year's survey, the total number of days surveying 
that will actually occur is likely to be much lower than the 160 days 
used to estimate total takes over the duration of the survey; 
therefore, this take estimate is likely to be conservative. Finally, 
NMFS will require that seismic survey operations involving the use of 
air guns and pingers cease if 30 beluga whales are detected in the 
Level B harassment zone and Apache must immediately report to NMFS if 
25 belugas are detected in that zone to allow us to consider making any 
necessary adjustments to monitoring and mitigation. As a result, due to 
the actual number of days and hours Apache is likely to be operating 
air guns near river mouths and taking into account the monitoring and 
mitigation measures applicable when operating seismic survey equipment 
near rivers, Apache expects the actual number of takes by Level B 
harassment estimated for Cook Inlet beluga whales to be no higher than 
(and likely much lower than) the numbers provided in the NMML analysis. 
This conclusion is also supported by (1) the survey's avoidance of 
areas of high beluga density in late spring and summer when most of 
Apache's surveying effort is expected to occur; (2) the availability of 
alternative, suitable beluga habitat outside of the areas ensonified to 
160 dB; (3) the beluga's tendency to avoid local noise sources when 
alternative, suitable habitat is available and they lack motivation to 
remain; and (4) the experience of Apache's survey operations in 2012, 
in which no observed takes of belugas occurred.

[[Page 12741]]



                                                Table 6--Probability of Sightings per Species for Year 2
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Shallow (356      Intermediate    Deep (455 km\2\)    Offshore (389         Total
                                                                     km\2\)          (458 km\2\)   ------------------      km\2\)      -----------------
                                                               ------------------------------------      20 days     ------------------     160 days
                            Species                                  20 days           20 days     ------------------     100 days     -----------------
                                                               ------------------------------------                  ------------------
                                                                  max      avg      max      avg      max      avg      max      avg      max      avg
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor seals..................................................     45.9     22.6     59.0     29.0     58.6     28.9    250.5    123.4      414    203.8
Harbor porpoises..............................................     12.8      0.4     16.4      0.6     16.3      0.6     69.7      2.4    115.2      4.0
Killer whales.................................................      0.8      0.1      1.0      0.1      1.0      0.1      4.3      0.6      7.2      1.0
Steller sea lions.............................................      2.5      0.8      3.2      1.1      3.2      1.0     13.6      4.5     22.5      7.4
--------------------------------------------------------------------------------------------------------------------------------------------------------

Estimated Take Conclusions

    Cetaceans--Effects on cetaceans are generally expected to be 
restricted to avoidance of an area around the seismic survey and short-
term changes in behavior, falling within the MMPA definition of ``Level 
B harassment.''
    The requested take numbers of individual cetaceans represent 
varying proportions of the populations of each species in Cook Inlet 
(Table 7). For Cook Inlet beluga whales, Apache requested 30 takes by 
Level B harassment. The authorized number of 30 beluga whale takes is 
based on NMML's estimate of 22 whales, which was adjusted by the 
average group size of approximately 8 whales reported during the 2012 
seismic survey to account for the fact that these whales often travel 
in groups. This number is approximately 10 percent of the population of 
approximately 312 animals (Shelden et al., 2012). NMFS will require 
Apache to immediately contact the Office of Protected Resources if 25 
belugas are detected in either the disturbance zone or the safety zone 
to discuss the need to make modifications to the monitoring and 
mitigation. If 30 belugas are detected in the disturbance zone, seismic 
survey operations involving the use of air guns and pingers must cease. 
For other cetaceans that might occur in the vicinity of the seismic 
survey in Cook Inlet, the requested takes represent an even smaller 
percentage of their respective populations. The requested takes of 10 
killer whales and 20 harbor porpoises represent 0.89 percent and 0.06 
percent of their respective populations in the proposed action area.
    Pinnipeds--Two pinniped species may be encountered in the proposed 
action area, but the harbor seal is likely to be the more abundant 
species in this area. The number of takes requested for individuals 
exposed to sounds at received levels >=160 dBrms re 1 [mu]Pa 
during the proposed seismic survey are as follows: harbor seals (200) 
and Steller sea lions (20). These numbers represent 0.69 percent and 
0.12 percent of their respective populations in the proposed action 
area.

                   Table 7--Authorized Number of Takes
------------------------------------------------------------------------
                                    Number of
             Species                authorized   Population   Percent of
                                      takes      abundance    population
------------------------------------------------------------------------
Beluga whales....................           30          312          9.6
Harbor seals.....................          200       29,175         0.69
Harbor porpoises.................           20       31,406         0.06
Killer whales....................           10        1,437         0.89
Steller sea lions................           20       41,197         0.12
------------------------------------------------------------------------

Determinations

Negligible Impact

    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as ``* * * 
an impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.'' In making a negligible impact determination, 
NMFS considers a variety of factors, including but not limited to: (1) 
The number of anticipated mortalities; (2) the number and nature of 
anticipated injuries; (3) the number, nature, intensity, and duration 
of Level B harassment; and (4) the context in which the takes occur.
    Given the required mitigation and related monitoring, no injuries 
or mortalities are anticipated to occur as a result of Apache's 
proposed seismic survey in Cook Inlet, and none are proposed to be 
authorized. Additionally, animals in the area are not expected to incur 
hearing impairment (i.e., TTS or PTS) or non-auditory physiological 
effects. The small number of takes that are anticipated are expected to 
be limited to short-term Level B behavioral harassment. Although it is 
possible that some marine mammal individuals may be exposed to sounds 
from seismic survey activities more than once, the duration of these 
multi-exposures is expected to be low since both the animals and the 
survey vessels will be moving constantly in and out of the survey area 
and the seismic air guns do not operate continuously all day, but for a 
few hours at a time totaling about 12 hours a day.
    Odontocete (including Cook Inlet beluga whales, killer whales, and 
harbor porpoises) reactions to seismic energy pulses are usually 
assumed to be limited to shorter distances from the air gun(s) than are 
those of mysticetes, in part because odontocete low-frequency hearing 
is assumed to be less sensitive than that of mysticetes. When in the 
Canadian Beaufort Sea in summer, belugas appear to be fairly responsive 
to seismic energy, with few being sighted within 6-12 mi (10-20 km) of 
seismic vessels during aerial surveys (Miller et al. 2005). However, as 
noted above, Cook Inlet belugas are more accustomed to anthropogenic 
sound than beluga whales in the Beaufort Sea. Accordingly, NMFS does 
not find this data determinative here. Also, due to the dispersed 
distribution of beluga whales in Cook Inlet during winter and the 
concentration of beluga whales in upper Cook Inlet from late April 
through early fall, belugas would likely

[[Page 12742]]

occur in small numbers in the phase two survey area during the survey 
period and few will likely be affected by the survey activity in a 
manner that would be considered behavioral harassment. In addition, due 
to the constant moving of the survey vessel, the duration of the noise 
exposure by cetaceans to seismic impulse would be brief. For the same 
reason, it is unlikely that any individual animal would be exposed to 
high received levels multiple times.
    Taking into account the mitigation measures that are planned, 
effects on cetaceans are generally expected to be restricted to 
avoidance of a limited area around the survey operation and short-term 
changes in behavior, falling within the MMPA definition of ``Level B 
harassment''. Animals are not expected to permanently abandon any area 
that is surveyed, and any behaviors that are interrupted during the 
activity are expected to resume once the activity moves away from the 
area. Only a very small portion of marine mammal habitat will be 
affected at any time, and other areas within Cook Inlet will be 
available for necessary biological functions. In addition, the area 
where the survey will take place is not known to be an important 
location where beluga whales congregate for feeding, calving, or 
nursing.
    Furthermore, while the estimated amount of take is not the 
principal factor in NMFS' negligible impact analysis, the estimated 
numbers of animals potentially exposed to sound levels sufficient to 
cause Level B harassment are low percentages of the population sizes in 
Cook Inlet, as shown in Table 7.
    Mitigation measures such as controlled vessel speed, dedicated 
marine mammal observers, non-pursuit, and shut downs or power downs 
when marine mammals are seen within defined ranges will further reduce 
short-term reactions and minimize any effects on hearing sensitivity. 
In all cases, the effects of the seismic survey are expected to be 
short-term, with no lasting biological consequence. Therefore, the 
exposure of cetaceans to sounds produced by the phase two seismic 
survey is not anticipated to have an effect on annual rates or 
recruitment or survival.
    Some individual pinnipeds may be exposed to sound from the proposed 
marine surveys more than once during the time frame of the project. 
However, as discussed previously, due to the constant moving of the 
survey vessel, the probability of an individual pinniped being exposed 
to sound multiple times is much lower than if the source is stationary. 
Taking into account the mitigation measures that are planned, effects 
on pinnipeds are generally expected to be restricted to avoidance of a 
limited area around the survey operation and short-term changes in 
behavior, falling within the MMPA definition of ``Level B harassment''. 
Animals are not expected to permanently abandon any area that is 
surveyed, and any behaviors that are interrupted during the activity 
are expected to resume once the activity moves out of the area. Only a 
very small portion of marine mammal habitat will be affected at any 
time, and other areas within Cook Inlet will be available for necessary 
biological functions. In addition, the area where the survey will take 
place is not known to be an important location where pinnipeds haulout. 
The closest known haulout site is located on Kalgin Island, which is 
about 22 km from the McArthur River. Therefore, NMFS has determined 
that the exposure of pinnipeds to sounds produced by the proposed 
seismic survey in Cook Inlet is not expected to result in more than 
Level B harassment and will not have an adverse effect on annual rates 
of recruitment or survival. Therefore, it is anticipated to have no 
more than a negligible impact on the animals.
    Potential impacts to marine mammal habitat were discussed 
previously in this document (see the ``Anticipated Effects on Habitat'' 
section). Although some disturbance is possible to food sources of 
marine mammals, the impacts are anticipated to be minor enough as to 
not affect rates of recruitment or survival of marine mammals in the 
area. Based on the size of Cook Inlet where feeding by marine mammals 
occurs versus the localized area of the marine survey activities, any 
missed feeding opportunities in the direct project area would be minor 
based on the fact that other feeding areas exist elsewhere.

Small Numbers

    The requested takes authorized under the MMPA represent 9.6 percent 
of the Cook Inlet beluga whale population of approximately 312 animals 
(Shelden et al., 2012), 0.89 percent of the combined Alaska resident 
stock and Gulf of Alaska, Aleutian Island and Bering Sea stock of 
killer whales (1,123 residents and 314 transients), and 0.06 percent of 
the Gulf of Alaska stock of approximately 31,046 harbor porpoises. The 
take requests presented for harbor seals represent 0.69 percent of the 
Gulf of Alaska stock of approximately 29,175 animals. The requested 
takes proposed for Steller sea lions represent 0.12 percent of the 
western stock of approximately 41,197 animals. These take estimates 
represent the percentage of each species or stock that could be taken 
by Level B behavioral harassment if each animal is taken only once. The 
number of marine mammals taken is small relative to the affected 
species or stocks. In addition, while NMFS' small numbers determination 
is based on the authorized amount of take, the mitigation and 
monitoring measures (described previously in this document) in the IHA 
are expected to prevent take from exceeding the amounts authorized and 
likely to reduce even further any potential disturbance to marine 
mammals.

Conclusion

    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 the total taking from Apache's proposed 
seismic survey in Cook Inlet will have a negligible impact on the 
affected species or stocks. NMFS also finds that small numbers of 
marine mammals will be taken relative to the populations of the 
affected species or stocks.

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

    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. 
NMFS has defined ``unmitigable adverse impact'' in 50 CFR 216.103 as: 
an impact resulting from the specified activity: (1) That is likely to 
reduce the availability of the species to a level insufficient for a 
harvest to meet subsistence needs by: (i) Causing the marine mammals to 
abandon or avoid hunting areas; (ii) Directly displacing subsistence 
users; or (iii) Placing physical barriers between the marine mammals 
and the subsistence hunters; and (2) That cannot be sufficiently 
mitigated by other measures to increase the availability of marine 
mammals to allow subsistence needs to be met.
    The subsistence harvest of marine mammals transcends the 
nutritional and economic values attributed to the animal and is an 
integral part of the cultural identity of the region's Alaska Native 
communities. Inedible parts of the whale provide Native artisans with 
materials for cultural handicrafts, and the hunting itself perpetuates 
Native

[[Page 12743]]

traditions by transmitting traditional skills and knowledge to younger 
generations (NOAA 2007). However, due to dramatic declines in the Cook 
Inlet beluga whale population, on May 21, 1999, legislation was passed 
to temporarily prohibit (until October 1, 2000) the taking of Cook 
Inlet belugas under the subsistence harvest exemption in section 101(b) 
of the MMPA without a cooperative agreement between NMFS and the 
affected Alaska Native Organizations (ANOs) (Public Law No. 106-31, 
section 3022, 113 Stat. 57,100). That prohibition was extended 
indefinitely on December 21, 2000 (Public Law No. 106-553, section 
1(a)(2), 114 Stat. 2762). NMFS subsequently entered into six annual co-
management agreements (2000-2003, 2005-2006) with the Cook Inlet Marine 
Mammal Council, an ANO representing Cook Inlet beluga hunters, which 
allowed for the harvest of 1-2 belugas. On October 15, 2008, NMFS 
published a final rule that established long-term harvest limits on the 
Cook Inlet beluga whales that may be taken by Alaska Natives for 
subsistence purposes (73 FR 60976). That rule prohibits harvest for a 
5-year period (2008-2012), if the average abundance for the Cook Inlet 
beluga whales from the prior five years (2003-2007) is below 350 
whales. The next 5-year period that could allow for a harvest (2013-
2017), would require the previous five-year average (2008-2012) to be 
above 350 whales.
    There is a low level of subsistence hunting for harbor seals in 
Cook Inlet. Seal hunting occurs opportunistically among Alaska Natives 
who may be fishing or travelling in the upper Inlet near the mouths of 
the Susitna River, Beluga River, and Little Susitna River. Consistent 
with NMFS' implementing regulations, Apache met with the Cook Inlet 
Marine Mammal Council (CIMMC)--a now dissolved ANO that represented 
Cook Inlet tribes--on March 29, 2011, to discuss the proposed 
activities and discuss any subsistence concerns. Apache also met with 
the Tyonek Native Corporation on November 9, 2010 and the Salamatof 
Native Corporation on November 22, 2010. Additional meetings were held 
with the Native Village of Tyonek, the Kenaitze Indian Tribe, and Knik 
Tribal Council, and the Ninilchik Traditional Council. According to 
Apache, during these meetings, no concerns were raised regarding 
potential conflict with subsistence harvest of marine mammals. Apache 
has identified the following features that are intended to reduce 
impacts to subsistence users:
     In-water seismic activities will follow mitigation 
procedures to minimize effects on the behavior of marine mammals and, 
therefore, opportunities for harvest by Alaska Native communities; and
     Regional subsistence representatives may support recording 
marine mammal observations along with marine mammal biologists during 
the monitoring programs and will be provided with annual reports.
    Since the issuance of the April 2012 IHA, Apache has maintained 
regular and consistent communication with federally recognized Alaska 
Natives. The Alaska Natives, Native Corporations, and ANOs that Apache 
has communicated with include: the Native Village of Tyonek; Tyonek 
Native Corporation; Ninilchik Native Association; Ninilchik Traditional 
Council; Salamatof Native Association; Knikatnu; Knik Native Council; 
Alexander Creek; Cook Inlet Region, Inc.; the Native Village of 
Eklutna; Kenaitze Indian Tribe; and Seldovia Native Assocaition. Apache 
has shared information gathered during the seismic survey conducted 
under the April 2012 IHA, and plans on hosting an information exchange 
with Alaska Native Villages, Native Corporations, and other Non-
Governmental Organizations in the spring of 2013 where data from the 
past year's monitoring operations would be presented.
    Apache concluded, and NMFS agrees, that the size of the affected 
area, mitigation measures, and input from the consultations Alaska 
Natives should result in the proposed action having no effect on the 
availability of marine mammals for subsistence uses. Apache and NMFS 
recognize the importance of ensuring that ANOs and federally recognized 
tribes are informed, engaged, and involved during the permitting 
process and will continue to work with the ANOs and tribes to discuss 
operations and activities.
    On February 6, 2012, in response to requests for government-to-
government consultations by the CIMMC and Native Village of Eklutna, 
NMFS met with representatives of these two groups and a representative 
from the Ninilchik. We engaged in a discussion about the proposed IHA 
for Area 1, the MMPA process for issuing an IHA, concerns regarding 
Cook Inlet beluga whales, and how to achieve greater coordination with 
NMFS on issues that impact tribal concerns. Following the publication 
of the proposed IHA, NMFS contacted the local Native Villages to inform 
them of the availability of the Federal Register notice and the opening 
of the public comment period. During the public comment period, NMFS 
received letters from two tribes--the Kenaitze Indian Tribe and the 
Seldovia Village Tribe--which were addressed in the Comment and 
Responses section of this notice.
    NMFS anticipates that any effects from Apache's proposed seismic 
survey on marine mammals, especially harbor seals and Cook Inlet beluga 
whales, which are or have been taken for subsistence uses, would be 
short-term, site specific, and limited to inconsequential changes in 
behavior and mild stress responses. NMFS does not anticipate that the 
authorized taking of affected species or stocks will reduce the 
availability of the species to a level insufficient for a harvest to 
meet subsistence needs by: (1) Causing the marine mammals to abandon or 
avoid hunting areas; (2) directly displacing subsistence users; or (3) 
placing physical barriers between the marine mammals and the 
subsistence hunters; and that cannot be sufficiently mitigated by other 
measures to increase the availability of marine mammals to allow 
subsistence needs to be met. Therefore, NMFS has determined that the 
proposed regulations will not have an unmitigable adverse impact on the 
availability of marine mammal stocks for subsistence uses.

Endangered Species Act (ESA)

    There are two marine mammal species listed as endangered under the 
ESA with confirmed or possible occurrence in the proposed project area: 
the Cook Inlet beluga whale and Steller sea lion. In addition, the 
proposed action would occur within designated critical habitat for the 
Cook Inlet beluga whales. NMFS' Permits and Conservation Division 
consulted with NMFS' Alaska Region Protected Resources Division under 
section 7 of the ESA on the issuance of the first IHA to Apache under 
section 101(a)(5)(D) of the MMPA, which analyzed the impacts in the 
other areas where Apache's has proposed to conduct seismic surveys, 
including Area 2. On May 21, 2012, NMFS' Alaska Region issued a revised 
biological opinion, which concluded that the IHA is not likely to 
jeopardize the continued existence of the marine mammal species (such 
as Cook Inlet beluga whales and Steller sea lions) affected by the 
seismic survey or destroy or adversely modify designated critical 
habitat for Cook Inlet beluga whales. Although the biological opinion 
considered the effects of multiple years of seismic surveying in the 
entire project area as a whole, see figure 6 of the biological opinion, 
to be cautious in light of the change in scope, NMFS' Permits and 
Conservation Division requested reinitiation of consultation

[[Page 12744]]

under Section 7 of the ESA to address these changes in the proposed 
action. A new Biological Opinion was issued on February 14, 2012. The 
Biological Opinion determined that the issuance of IHA is not likely to 
jeopardize the continued existence of the Cook Inlet beluga whales or 
the western DPS of Steller sea lions, or destroy or adversely modify 
Cook Inlet beluga whale critical habitat. Finally, the Biological 
Opinion includes an Incidental Take Statement (ITS) for Cook Inlet 
beluga whales and Steller sea lions. The ITS contains reasonable and 
prudent measures implemented by terms and conditions to minimize the 
effects of this take.

National Environmental Policy Act (NEPA)

    NMFS prepared an Environmental Assessment to determine whether this 
proposed activity will have a significant effect on the human 
environment. This analysis was completed prior to the issuance the IHA 
with NMFS' issuance of a Finding of No Significant Impact (FONSI).

Authorization

    NMFS has issued an incidental harassment authorization for the take 
of marine mammals incidental to Apache's seismic survey in Cook Inlet, 
Alaska, provided the previously mentioned mitigation, monitoring, and 
reporting requirements are incorporated.

    Dated: February 20, 2013.
Helen M. Golde,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2013-04202 Filed 2-22-13; 8:45 am]
BILLING CODE 3510-22-P