[Federal Register Volume 76, Number 149 (Wednesday, August 3, 2011)]
[Notices]
[Pages 46729-46753]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-19663]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XA396


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Shallow Hazards Survey in the 
Chukchi Sea, Alaska

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

ACTION: Notice; issuance of an incidental take authorization.

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SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA) 
regulations, notification is hereby given that NMFS has issued an 
Incidental Harassment Authorization (IHA) to Statoil USA E&P Inc. 
(Statoil) to take, by harassment, small numbers of 13 species of marine 
mammals incidental to shallow hazards and geotechnical surveys in the 
Chukchi Sea, Alaska, during the 2011 Arctic open-water season.

DATES: Effective August 1, 2011, through November 30, 2011.

ADDRESSES: Inquiry for information on the incidental take authorization 
should be addressed to P. Michael Payne, Chief, Permits, Conservation 
and Education Division, Office of Protected Resources, National Marine 
Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910. A 
copy of the application containing a list of the references used in 
this document, NMFS' 2010 Environmental Assessment (EA), 2011 
Supplemental Environmental Assessment (SEA), Finding of No Significant 
Impact (FONSI), and the IHA may be obtained by writing to the address 
specified above, telephoning the contact listed below (see FOR FURTHER 
INFORMATION CONTACT), or visiting the Internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.
    Documents cited in this notice may be viewed, by appointment, 
during regular business hours, at the aforementioned address.

FOR FURTHER INFORMATION CONTACT: Shane Guan, Office of Protected 
Resources, NMFS, (301) 427-8401 or Brad Smith, NMFS, Alaska Region, 
(907) 271-3023.

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 (Secretary) to allow, upon request, 
the incidental, but not intentional taking 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 regulations are issued or, if the taking is limited to 
harassment, a notice of a proposed authorization is provided to the 
public for review.
    Authorization shall be granted if NMFS finds that the taking will 
have a negligible impact on the species or stock(s), will not have an 
unmitigable adverse impact on the availability of the species or 
stock(s) for subsistence uses (where relevant), and if the permissible 
methods of taking and requirements pertaining to the mitigation, 
monitoring and reporting of such taking are set forth.
    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as:

    An impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.

    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which citizens of the U.S. can apply for an authorization to 
incidentally take small numbers of marine mammals by harassment. 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].

    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 issuance of the authorization.

Summary of Request

    NMFS received an application on March 1, 2011, from Statoil for the 
taking, by harassment, of marine mammals incidental to shallow hazards 
site surveys and soil investigations (geotechnical boreholes) in the 
Chukchi Sea, Alaska, during the 2011 open-water season. After 
addressing comments from NMFS, Statoil modified its application and 
submitted a revised application on April 19, 2011. The April 19, 2011, 
application was the one available for public comment (see ADDRESSES) 
and considered by NMFS for the IHA.
    The shallow hazards and site clearance surveys would use a towed 
airgun cluster consisting of four, 10-in\3\ airguns with a ~600 m 
(1,969 ft) towed hydrophone streamer, as well as additional lower-
powered and higher frequency survey equipment for collecting 
bathymetric and shallow sub-bottom data. The proposed survey will take 
place on and near Statoil's leases in the Chukchi Sea, covering a total 
area of ~665 km\2\ located ~240 km (150 mi) west of Barrow and ~165 km 
(103 mi) northwest of Wainwright, in water depths of ~30-50 m (100-165 
ft).
    The geotechnical soil investigations will take place at prospective 
drilling locations on Statoil's leases and leases jointly owned with 
ConocoPhillips Alaska Inc. (CPAI). All cores will be either 5.3 cm or 
7.1 cm (2.1 in. or 2.8 in.) in diameter (depending on soil

[[Page 46730]]

type), and those collected at prospective drilling locations will be up 
to 100 m (328 ft) in depth. The maximum total number of samples 
collected as part of the drilling location and site survey program will 
be ~29.
    Statoil intends to conduct these marine surveys during the 2011 
Arctic open-water season (July through November). Impacts to marine 
mammals may occur from noise produced from active acoustic sources 
(including airguns) used in the surveys.

Description of the Specified Activity

    Statoil acquired 16 leases in the Chukchi Sea during Lease Sale 193 
held in February 2008. The leased areas are located ~240 km (150 mi) 
west of Barrow and ~160 km (~100 mi) northwest of Wainwright. During 
the open-water season of 2010, Statoil conducted a 3D seismic survey 
over its lease holdings and the surrounding area. The data gathered 
during that survey are currently being analyzed in order to determine 
potential well locations on the leases. These analyses will be 
completed prior to commencement of the site survey program. During the 
open-water season of 2011, Statoil proposes to conduct shallow hazards 
and site clearance surveys (site surveys) and soil investigations 
(geotechnical boreholes).
    The operations will be performed from two different vessels. 
Shallow hazards surveys will be conducted from the M/V DUKE, while 
geotechnical soil investigations will be conducted from the M/V FUGRO 
SYNERGY (see Statoil's application for vessel specifications). Both 
vessels will mobilize from Dutch Harbor in late July and arrive in the 
Chukchi Sea to begin work on or after August 1. Allowing for poor 
weather days, operations are expected to continue into late September 
or early October. However, if weather permits and all planned 
activities have not been completed, operations may continue as late as 
November 15.
    The site survey work on Statoil's leases will require approximately 
23 days to complete. Geotechnical soil investigations on Statoil leases 
and on leases jointly held with CPAI will require ~14 days of 
operations.

Shallow Hazards and Site Clearance Surveys

    Shallow hazards site surveys are designed to collect bathymetric 
and shallow sub-seafloor data that allow the evaluation of potential 
shallow faults, gas zones, and archeological features at prospective 
exploration drilling locations, as required by the Bureau of Ocean 
Energy Management, Regulation and Enforcement (BOEMRE). Data are 
typically collected using multiple types of acoustic equipment. During 
the site surveys, Statoil proposes to use the following acoustic 
sources: 4 x 10 in\3\ airgun cluster, single 10 in\3\ airgun, Kongsberg 
SBP3000 sub-bottom profiler, GeoAcoustics 160D side-scan sonar, and a 
Kongsberg EM2040 multi-beam echosounder. The acoustic characteristics 
(including operating frequencies and estimated source levels) of all 
active sources are described in the Federal Register notice for the 
proposed IHA (76 FR 30110; May 24, 2011). That information has not 
changed and is therefore not repeated here.

Geotechnical Soil Investigations

    Geotechnical soil investigations are performed to collect detailed 
data on seafloor sediments and geological structure to a maximum depth 
of 100 m (328 ft). These data are then evaluated to help determine the 
suitability of the site as a drilling location. Statoil has contracted 
with Fugro who will use the vessel M/V FUGRO SYNERGY to complete the 
planned soil investigations. Three to four bore holes will be collected 
at each of up to 5 prospective drilling locations on Statoil's leases, 
and up to 3 boreholes may be completed at each of up to 3 potential 
drilling locations on leases jointly owned with CPAI. This would result 
in a maximum total of 29 bore holes to be completed as part of the 
geotechnical soil investigation program. The FUGRO SYNERGY operates a 
Kongsberg EA600 Echosounder and uses a Kongsberg 500 high precision 
acoustic positioning (HiPAP) system for precise vessel positioning 
while completing the boreholes. The acoustic characteristics (including 
operating frequencies and estimated source levels) of all active 
sources, as well as the sounds produced during soil investigation 
sampling, are described in the Federal Register notice for the proposed 
IHA (76 FR 30110; May 24, 2011). That information has not changed and 
is therefore not repeated here.

Comments and Responses

    A notice of NMFS' proposal to issue an IHA to Statoil published in 
the Federal Register on May 24, 2011 (76 FR 30110). That notice 
described, in detail, Statoil's proposed activity, the marine mammal 
species that may be affected by the activity, and the anticipated 
effects on marine mammals and the availability of marine mammals for 
subsistence uses. During the 30-day public comment period, NMFS 
received three comment letters from the following: The Marine Mammal 
Commission (Commission); the Alaska Eskimo Whaling Commission (AEWC); 
and Alaska Wilderness League (AWL), Center for Biological Diversity, 
Defenders of Wildlife, Earthjustice, Natural Resources Defense Council, 
Oceana, Pacific Environment, and Sierra Club (collectively ``AWL''). 
The AEWC submitted a copy of the 2011 Conflict Avoidance Agreement 
(CAA), since Statoil declined to sign the CAA.
    Any comments specific to Statoil's application that address the 
statutory and regulatory requirements or findings NMFS must make to 
issue an IHA are addressed in this section of the Federal Register 
notice.

MMPA Concerns

    Comment 1: AEWC states that Statoil's IHA application NMFS released 
is incomplete because it did not contain a copy of the Plan of 
Cooperation (POC). AEWC points out that Statoil stated that it ``is 
developing a Plan of Cooperation (POC) for their proposed 2011 
activities.'' (Statoil IHA Application at page 51), and since Statoil 
did not provide the POC or any detail on the measures to be adopted in 
compliance with 50 CFR 216.104(a)(12)(iii), NMFS cannot make the 
determination required under the MMPA. AEWC further points out that 
NMFS has previously stated that ``[i]t should be understood that the 
POC is required by NMFS's implementing regulations to be submitted as 
part of the industry's IHA application'' (74 FR 55368, 55393; October 
27, 2009). AEWC requests that NMFS enforce the requirement that Statoil 
set forth, in its application, the proposed measures employed to 
prevent conflicts with subsistence activities.
    Response: Although NMFS agrees with AEWC's statement that a POC is 
essential for making the determination for granting an IHA to the 
industry, it is not used to determine the completeness of an IHA 
application. A complete IHA application should address all fourteen 
questions in NMFS' marine mammal incidental take application 
guidelines, which can be found at http://www.nmfs.noaa.gov/pr/permits/incidental.htm#apply. Concerning the POC, as stated in item 12 of the 
application guideline, the applicant ``must submit either a `plan of 
cooperation' or information that identifies what measures have been 
taken and/or will be taken to minimize any adverse effects on the 
availability of marine mammals for subsistence uses.'' In the case of 
Statoil's IHA application, NMFS believes that the company provided 
detailed information that identified what measures have been

[[Page 46731]]

taken and will be taken to minimize any adverse effects to subsistence 
harvesting of marine mammals, such as maintaining an open and 
transparent process with all stakeholders throughout the duration of 
its activities in the Chukchi Sea, identifying transit routes and 
timing to avoid other subsistence use areas and communicating with 
coastal communities before operating in or passing through these areas. 
In addition, Statoil completed the early phase of the POC process for 
the proposed project by meeting with the North Slope Borough Department 
of Wildlife Management (December 2010) and the AEWC (mini-convention in 
Barrow, February 2011), and arranged to visit and hold public meetings 
in the affected Chukchi Sea villages, including Pt. Hope, Pt. Lay, 
Wainwright, and Barrow during the week of March 21, 2011. NMFS 
determined that these activities showed that Statoil was in the process 
of finalizing its POC with the Native communities, therefore NMFS 
determined that Statoil's application was complete. Subsequently on 
June 20, 2011, NMFS received a draft POC with detailed information on 
the POC process. On July 14, 2011, NMFS received the final POC from 
Statoil.

Impacts to Marine Mammals

    Comment 2: AWL states that NMFS's uniform marine mammal harassment 
threshold for impulsive sounds does not take into account the 
documented reactions of specific species found in the Arctic to much 
lower received levels. The AWL argues by providing an example that 
harbor porpoises have been shown to be exceptionally sensitive to 
noise, and NMFS has used 120 dB as the appropriate threshold when 
authorizing marine mammal take for Navy sonar activities. In addition, 
the AWL states, by referring to Southall et al. (2007), that ``a 2007 
study found that for migrating bowheads `the onset of significant 
behavioral disturbance from multiple pulses occurred at [received 
levels] around 120 dB re: 1 [mu]Pa[.]' ''. The AWL concludes that ``the 
2007 study in fact determined that the reactions of migrating bowhead 
whales to sounds as low as 120 dB had a `higher potential' for 
affecting foraging, reproduction, or survival rates.''
    Response: NMFS does not agree with AWL's assessment on acoustic 
effects of marine mammals. The 120 dB threshold for the onset of 
behavioral harassment for harbor porpoise by Navy sonar activities is 
limited to exposure to mid- and high-frequency sonar signals, which are 
defined as sound with dominant frequency at 1-10 kHz and above 10 kHz, 
respectively. This is because harbor porpoise is considered a ``high 
frequency cetacean'' (Southall et al. 2007), and, therefore, is more 
sensitive to noise exposure at higher frequency spectra. Sounds 
produced during marine seismic surveys have most of their energy 
concentrated at the lower end of the frequency spectra, which is 
largely outside of the harbor porpoises' hearing threshold (Andersen 
1970; Kastelein et al. 2002). Therefore, NMFS believes that it is 
scientifically justifiable to use received level at 120 dB as the 
threshold for behavioral harassment for harbor porpoises exposed to 
mid- and high-frequency Navy sonar, but it is not appropriate to use 
this received level as the threshold for behavioral harassment when 
exposed to seismic sounds.
    Regarding its comment on bowhead disturbances when exposed to 
seismic sound at received level of 120 dB, AWL incorrectly cited the 
reference in Southall et al. (2007) as ``a 2007 study.'' In fact, the 
reference in Southall et al. (2007) that AWL refers to was a conference 
abstract presented at the 1999 Meeting of the Acoustical Society of 
America by Richardson et al. (1999) titled ``Displacement of Migrating 
Bowhead Whales by Sounds from Seismic Surveys in Shallow Waters of the 
Beaufort Sea.'' The study was conducted in the summer months between 
1996 and 1998 in shallow waters of the Beaufort Sea, Alaska, during 
seismic surveys with 6-16 airguns and total volumes of 560-1,500 in\3\. 
As stated in the abstract, ``[w]estward autumn migration of bowhead 
whales near and offshore of the exploration area was monitored by 
aerial surveys flown daily, weather permitting, during the three 
seasons. Aerial survey data from days with and without airgun 
operations were compared.'' The authors observed that ``[m]ost bowheads 
avoided the area within 20 km of the operating airguns; bowheads were 
common there on days without airgun operations.'' In addition, the 
authors stated that bowhead whale ``sighting rates just beyond the 
avoidance zone were higher on days with airgun operations. Broadband 
received levels of airgun pulses at 20 km were typically 120-130 dB re: 
1 [micro]Pa (rms over pulse duration).'' Based on this description, 
NMFS concludes that the displacement of bowhead whales by seismic 
surveys constitutes temporary avoidance behavior during ``days with 
airgun operations,'' and these whales seem to avoid an area where 
received levels were about 120-130 dB. The authors did not state that 
they observed ``significant behavioral disturbance,'' nor did they 
report a disruption of behavioral patterns, either of which could be an 
indication of Level B harassment.
    In addition, these minor course changes occurred during migration 
and have not been seen at other times of the year and during other 
activities. Therefore, NMFS does not believe that minor course 
corrections during a migration equate to ``take'' under the MMPA. This 
conclusion is based on controlled exposure experiments conducted on 
migrating gray whales exposed to the U.S. Navy's low frequency sonar 
(LFA) sources (Tyack 2009). When the source was placed in the middle of 
the migratory corridor, the whales were observed deflecting around the 
source during their migration. However, such minor deflection is 
considered not to be biologically significant. To show the contextual 
nature of this minor behavioral modification, recent monitoring studies 
of Canadian seismic operations indicate that when, not migrating, but 
involved in feeding, bowhead whales do not move away from a noise 
source at an SPL of 160 dB. Therefore, while bowheads may avoid an area 
of 20 km (12.4 mi) around a noise source, when that determination 
requires a post-survey computer analysis to find that bowheads have 
made a 1 or 2 degree course change, NMFS believes that does not rise to 
the level of a ``take.'' NMFS therefore continues to estimate 
``takings'' under the MMPA from impulse noises, such as seismic, as 
being at a distance of 160 dB (re 1 [micro]Pa) from the source. 
Although it is possible that marine mammals could react to any sound 
levels detectable above the ambient noise level within the animals' 
respective frequency response range, this does not mean that such 
animals would react in a biologically significant way.
    Therefore, unless and until an improved approach is developed and 
peer-reviewed, NMFS will continue to use the 160-dB threshold for 
determining the level of take of marine mammals by Level B harassment 
for impulse noise (such as from airguns).
    Comment 3: In reference to the impact analysis NMFS provided in the 
Federal Register notice for the proposed IHA (76 FR 30110; May 24, 
2011), AWL states that the existing science does not support strictly 
distinguishing impulse and non-impulse noise, and that NMFS recognizes 
that over long distances (tens of kilometers), impulse sounds can 
become ``stretched'' out. Further, AWL refers to the peer-review panel 
report for this year's Open Water Meeting noting

[[Page 46732]]

that phenomenon and concluding that sounds from airguns ``should not be 
treated as truly impulsive when received at ranges where sound 
propagation is known to remove the impulsive nature of these signals.'' 
AWL concludes that ``a uniform 160-dB harassment threshold is not 
justified by either the science or the standards imposed by the MMPA. 
And, without an appropriate threshold, NMFS cannot begin to accurately 
gauge the extent of marine mammal take from Statoil's operations.''
    Response: Although NMFS agrees with AWL that at long distances an 
impulse acoustic signal will lose its pulse feature by stretching its 
duration due to multipath propagation, these signals (or noises) are 
still fundamentally different from other non-impulse noise sources such 
as those from vibratory pile driving, drilling, and dredging based on 
the following characteristics:
    First, the elongated pulse signals from the airgun array at far 
distances are caused by multipath propagation in a reverberant 
environment (Greene and Richardson 1988; Richardson et al. 1995; Madsen 
et al. 2002; Lurton 2002), which is different from other non-pulse 
signals at closer distances, which is composed of mostly direct sound. 
The reverberation part of the sound in the ocean behaves differently 
compared to the direct sound and early surface and bottom reflections 
from the perspective of the receiver. The direct sound and early 
reflections follow the inverse square law, with the addition of 
absorption effects in the case of early reflections, and so their 
amplitude varies with distance. However the reverberant part of the 
sound remains relatively constant up to a large distance with the 
position of the receiver. Therefore, as distance increases from the 
source, the component of reverberant sounds increases against the 
direct sound. In addition, the reverberant energy is less directional 
and is distributed more uniformly around the ambient environment of the 
animal. As shown in human psychoacoustics, these characteristics in a 
reverberant field provide distance cues to the listener as to how far 
away the source is located (Howard and Angus 2006). Therefore, at a 
distance where the airgun signals have been ``stretched'' to non-pulse, 
the receiving animals would be able to correctly perceive that these 
sounds are coming from far away, and would thus be less likely to be 
affected behaviorally as behavior responses are not solely dependent on 
received levels. Other factors such as distance to the source, movement 
of the source, source characteristics, and the receiver's (i.e., 
animal's) age, sex, motivation states, and prior experience, etc. 
probably play more significant roles in determining the responses of 
the animals that are being exposed to lower levels of noises than 
solely the received sound level.
    Second, even though during horizontal propagation, the initial 
short pulse could be ``stretched'' from milliseconds when emitted to 
about 0.25-0.5 second long at a few kilometers in shallow water 
(Richardson et al. 1995), the noise duration is still very short when 
compared to those ``conventional'' non-pulse noise sources (vibratory 
pile driving, drilling, and dredging, etc.) for which NMFS applies a 
120 dB threshold for assessing behavioral harassment. The empirical 
measurements of a 3,000 in\3\ airgun array received signal 
characteristics showed that its pulse duration was stretched to 0.2 
second at approximately 1.3 km (0.8 mi), to 0.5 second at approximately 
10 km (6.2 mi), and to about 1.8 seconds at 80 km (50 mi) from the 
source (O'Neill et al. 2011). Based on the airgun array's firing rate 
of 0.1 Hz (1 shot every 10 seconds), the duty cycle was only 18% for 
the signal at 80 km (50 mi) (1.8 seconds on for every 10 seconds). 
Conversely, the ``conventional'' non-pulse noises from vibratory pile 
driving, drilling, and dredging typically last much longer (minutes to 
hours) with very brief (seconds for vibratory pile driving) intervals.
    Therefore, NMFS does not agree that it is appropriate to treat 
elongated airgun pulses at long distances as a ``conventional'' non-
pulse signal and apply the 120 dB behavioral response threshold to that 
sound source.
    Comment 4: AWL states that NMFS' approach to determining take for 
Statoil's surveying during the bowhead fall migration is not 
supportable because the proposed authorization does not adequately take 
into account that Statoil's fall surveying will take place within a 
migratory corridor. AWL argues that ``by relying on density without 
sufficiently considering the overlap of ensonified areas, it assumes 
that migratory animals remain relatively stationary from one day to the 
next, despite Statoil's operations exposing the same areas of the ocean 
to elevated sound level at very different times, days or even weeks 
apart.'' AWL further states that ``NMFS' calculations are premised on 
the notion that a bowhead whale exposed, for example, on day 15 during 
the course of the survey remains stationary and is the same whale 
exposed when the vessel travels near the area again on day 23 during 
the detailed survey, amounting to only a single harassed whale. Such a 
result does not reflect the reality of whales moving through the 
surveying area on their way to wintering grounds in the Bering Sea.'' 
AWL points out that ``in the past, NMFS has avoided this problem by 
calculating the ensonified area based on the amount of linear surveying 
line, rather than by extending the boundaries of the area to be 
surveyed.''
    Response: NMFS does not agree with AWL's statement that our take 
estimates for bowhead whales during Statoil's shallow hazards survey in 
the Chukchi Sea are ``not supportable.'' First, evidence has shown that 
the bowhead whale fall migratory route through the Chukchi Sea is more 
spread out than in the Beaufort Sea, where whales tend to have a more 
confined migratory corridor due to ice conditions. In a recent 
satellite tagging study, Quakenbush et al. (2010) concluded from GPS 
data that bowhead whales do not spend much time in the north-central 
Chukchi Sea, near Statoil's 2011 proposed shallow hazards survey. 
Kernel densities from the study showed that areas with the highest 
probability of bowhead use from September to December were near Point 
Barrow and the northeast Chukotka coast; the area along the east coast 
of Wrangel Island also had a moderate probability of use (Quakenbush et 
al. 2010). In addition, movements and behavior of tagged bowhead whales 
in this study indicated that the greatest potential for disturbance 
from industrial activities is near Point Barrow in September and 
October and in the lease area in September. Lastly, Statoil's shallow 
hazards survey is scheduled to begin on August 1, 2011, and would 
require approximately 23 days to complete. Therefore, there is the 
potential for Statoil to complete their entire operation prior to the 
time when bowhead whales typically begin entering the Chukchi Sea in 
the fall (i.e., mid-September). Thus NMFS determined that the marine 
mammal density data provided in Statoil's IHA application for this 
period are overestimated. And to compensate for the overestimation due 
to the lower than actual density, NMFS opted not to consider overlaps 
of the ensonified area.
    Additionally, it should be noted that this is not the first time 
that this approach has been used in estimating takes from shallow 
hazards and 3D seismic surveys. When airgun activity, as part of a 
shallow hazards survey is ongoing continuously after ramping up, it is 
expected that nearly all bowhead whales would avoid the areas 
ensonified to >160 dB. This would

[[Page 46733]]

mean that migrating whales passing through the region would likely 
avoid the immediate area around the activities, and thus not be 
``taken'' repeatedly by exposure to sounds >160 dB.
    Alternatively, bowhead take numbers can be calculated based on the 
migratory animals' daily average multiplied by the duration in days 
when seismic activities are ongoing, as was typically done to estimate 
bowhead whale takes in the Beaufort Sea during their migration. 
However, no such data are available for migratory bowheads in the 
Chukchi Sea, therefore, this method cannot be applied.
    Regarding the method NMFS used to estimate the take by calculating 
the ensonified area based on the amount of linear surveying line, 
rather than by extending the boundaries of the area to be surveyed, 
this method is used for 2D seismic surveys where there is no 
overlapping ensonified area. Using this methodology to calculate for 
overlapping ensonified area would result in an unrealistically large 
area (in some cases, it could be larger than the entire Chukchi Sea) 
being treated as the affected area, which NMFS does not think is 
appropriate.
    Comment 5: AWL states that NMFS must include the effects from all 
of Statoil's equipment, not only the noise from the airguns (surveying) 
and ship thrusters (drilling). AWL points out that this year's peer-
review panel found that Statoil's other acoustic sources are 
``relatively powerful and operate in the acoustic band of many if not 
most marine mammals.'' AWL further states that although NMFS has 
proposed that Statoil conduct field measurements for all its equipment 
in order to determine whether additional safety zones are required, 
this cannot cure the failure to accurately determine in advance the 
number of marine mammals that may be harassed by Statoil's activities. 
AWL states that NMFS should further consider the fact that Statoil's 
two exploratory activities (surveying and drilling) may take place in 
close proximity to one another, each using a variety of noise-producing 
equipment that could contribute to adverse synergistic effects.
    Response: NMFS agrees with AWL that all of Statoil's active 
acoustic equipment must be included and analyzed for their potential 
effects on marine mammals. In its Federal Register notice of proposed 
IHA (76 FR 30110; May 24, 2011) and the SEA, NMFS provided a detailed 
description and analysis of these active acoustic sources. A list of 
these sources with their frequency bandwidth and modeled/known maximum 
source level are provided in Table 1-3 of the SEA. These sources 
include the Kongsberg EA600 echosounder, GeoAcoustics 160D side-scan 
sonar, Kongsberg SBP300 sub-bottom profiler, Kongsberg EM2040 multibeam 
echosounder, and Kongsberg HiPAP 500. All these active sources are 
expected to have maximum source levels below those of the airgun array 
except the GeoAcoustics 160D side-scan sonar, of which the maximum 
source level is approximately 233 dB re 1 [mu]Pa @ 1m. However, since 
this equipment operates at frequencies of 114 and 410 kHz, the modeled 
isopleths drop down to 160 dB at about 453 and 108 m (1,486 and 354 ft) 
from the source, and to 120 dB at about 1,177 and 221 m (3,861.5 and 
725 ft) from the source for each of these two frequencies, 
respectively, when high-frequency absorption is taken into 
consideration. These distances are well within the modeled 160 dB and 
120 dB zones for the airgun array, which is at 2,250 m and 39,000 m 
(1.4 mi and 24 mi) for received levels of 160 and 120 dB, respectively. 
Therefore, the acoustic footprints from all other active sources are 
contained within that of the airgun array, and no additional take from 
these sources is expected.
    Nevertheless, as mentioned by AWL and described in detail in the 
proposed IHA (76 FR 30110; May 24, 2011), Statoil will be required to 
conduct sound source verification (SSV) tests for all acoustic 
equipment used during the proposed shallow hazards survey. The 
empirical measurements will further show the presence or absence of 
low-frequency side-lobes and will be used to refine the exclusion 
zones, which are required for implementing monitoring and mitigation 
measures, as needed.
    NMFS is aware of the relative locations of Statoil's two 
exploratory activities (shallow hazards survey and geotechnical survey) 
and has conducted appropriate analyses concerning sources and impacts 
from both activities. These analyses are described in detail in the 
proposed IHA (76 FR 30110; May 24, 2011) and the SEA. Please refer to 
those documents for that discussion.

Mitigation Measures

    Comment 6: AWL states that ``NMFS should consider a safety zone 
specific to cow-calf pairs'' to provide additional protective measures 
to address uncertainties regarding impacts on ``bowhead cow-calf pairs 
and aggregations of whales.''
    Response: Although it has been suggested that female baleen whales 
with calves ``show a heightened response to noise and disturbance,'' 
there is no evidence that such ``heightened response'' is biologically 
significant and constitutes a ``take'' under the MMPA. Nevertheless, in 
the past NMFS has required a 120-dB safety zone for migrating bowhead 
cow/calf pairs to be implemented (see Federal Register notice for 
proposed IHA to Shell; 75 FR 22708; May 18, 2010). However, in the 
Chukchi Sea, the migratory corridor for bowhead whales is wider and 
more open, thus the 120-dB ensonified zone would not impede bowhead 
whale migration. The animals would be able to swim around the 
ensonified area. Additionally, NMFS has not imposed a requirement to 
conduct aerial monitoring of the 120-dB safety zone for the occurrence 
of four or more cow-calf pairs in the Chukchi Sea because it is not 
practicable. Especially for Statoil's proposed shallow hazards survey, 
NMFS determined that monitoring the 120-dB zone of influence was not 
necessary in the Chukchi Sea because there would not be the level of 
effort by these surveys (i.e., a small 120-dB zone of about 39,000 m 
radius). This provides cow/calf pairs with sufficient ability to move 
around the seismic source without significant effort.

Monitoring Measures

    Comment 7: The Commission recommends that prior to granting the 
requested authorization, NMFS provide additional justification for its 
preliminary determination that the proposed monitoring program will be 
sufficient to detect, with a high level of confidence, all marine 
mammals within or entering the identified Level B harassment zones.
    Response: For this action, marine mammal monitoring serves two 
primary purposes. One purpose (referred to as mitigation monitoring) is 
to trigger mitigation measures--so that when a marine mammal is sighted 
within or entering the identified 180 or 190-dB exclusion zones, 
appropriate measures (speed/course change, power-down, or shutdown of 
sound sources) can be implemented, thus minimizing the likelihood that 
marine mammals are exposed to sound levels that have been associated 
with injurious effects. The other purpose is to collect data regarding 
the behavior and numbers of marine mammals detected within the larger 
160-dB zone, which can be used both to refine Level B take estimates 
and to add to our understanding of the nature and scale of marine 
mammal behavioral responses to this activity. In the Federal Register 
notice for the proposed IHA (76 FR 30110; May 24, 2011), NMFS provided 
a thorough analysis of the proposed monitoring

[[Page 46734]]

measures and made a preliminary determination, based on the modality 
that is proposed to be utilized for monitoring, prior years' marine 
mammal visual monitoring measures as reported in the 90-day reports and 
comprehensive reports for seismic surveys in the Arctic, and the small 
exclusion zones (50 m [164 ft] from the source to where received levels 
would be at 190 dB and above, and 190 m [623 ft] from the source to 
where received levels would be at 180 dB and above) anticipated during 
the proposed Statoil shallow hazards surveys. The analysis led NMFS to 
conclude that the proposed monitoring program will be sufficient to 
detect, with a high level of confidence, nearly all marine mammals 
within or entering the identified 180 and 190 dB exclusion zone to 
implement mitigation measures to prevent Level A harassment (injury).
    The identified Level B harassment zone for Statoil's proposed 
shallow hazards survey is modeled at 2,250 m (1.4 mi) from the source. 
This distance is believed to be within reasonable range for visual 
detection based on prior years' marine mammal monitoring during seismic 
surveys in the Arctic (Aerts et al. 2008; Hauser et al. 2008; 
Brueggeman 2009; Ireland et al. 2009; Reiser et al. 2010; 2011; Blees 
et al. 2011). In addition, NMFS worked with Statoil on the 
implementation of recommendations from the independent peer-review 
panel of Statoil's monitoring plan and included a list of monitoring 
measures recommended by the panel in the IHA. These measures that will 
increase detectability include: (1) Maximizing the time spent looking 
at the water and guarding the exclusion zones; (2) using ``big eye'' 
binoculars (e.g., 25 x 150 power) from high perches on large, stable 
platforms; (3) pairing the use of ``big eyes'' with naked eye 
searching; and (4) using the best possible positions for observing 
(e.g., outside and as high on the vessel as possible), taking into 
account weather and other working conditions. All these measures will 
further increase marine mammal detectability within and around the 
zones of influence for Level B harassment.
    Although it may be difficult to detect all marine mammals that are 
within or entering the larger 160-dB Level B harassment zone, these 
observations will be corrected for animals undetected in the far field 
and used to refine post-activity take estimates, which are then 
reported in the 90-day report. Additionally, behavioral observations 
within this zone are reported and more generally contribute to our 
understanding of how marine mammals behaviorally respond to seismic 
surveys.
    Comment 8: AWL states that the IHA must prescribe the ``means of 
effecting the least practicable impact'' on a species or stock and its 
habitat, therefore, AWL argues, NMFS should also determine whether 
there are further monitoring methods available, such as manned or 
unmanned aerial surveys. Citing the peer-review panel report on open 
water monitoring plans, AWL states that other far-field monitoring, 
such as the use of scout vessels, passive acoustic platforms, and 
satellites, should be studied as well. AWL argues that ``in order to 
mitigate for some of the difficulties that arise from relying on visual 
observation, NMFS should consider restricting airgun operations to 
times in which the safety zones are visible to marine monitors,'' and 
that ``Statoil should not operate in conditions--such as darkness, fog, 
or rough seas--in which the observers are unable to ensure that the 
designated safety zones are free of marine mammals.''
    Response: During preparation of the SEA, NMFS considered several 
additional technologies that could be used to enhance marine mammal 
monitoring. These new technologies include the use of unmanned aerial 
vehicles (UAVs), passive acoustic monitoring (PAM), and active acoustic 
monitoring (AAM) for marine mammals. However, at this time, these 
technologies are still being developed or refined. For example, while 
there has been some testing of unmanned aerial vehicles conducted 
recently, the technology has not yet been proven effective for 
monitoring or mitigation, as would be required under an IHA.
    Regarding the use of PAM, NMFS does not believe that at the current 
stage, requiring PAM (either towed or stationary) for real-time 
acoustic monitoring would yield reliable data (Guan et al. 2011). 
During the 2010 open-water seismic survey, Statoil tested a towed PAM 
for the presence of bowhead whales onboard a support vessel during the 
seismic operations, and preliminary results show that the detection 
rates were low (Bruce Martin, pers. comm. March 2011). As far as AAM is 
concerned, many technical issues (such as detection range and 
resolution) and unknowns (such as target strength of marine mammal 
species in the Arctic) remain to be resolved before it can be used as a 
reliable monitoring tool to aid in the implementation of mitigation 
measures. Environmental consequences concerning additional sound being 
introduced into the water column from an active sonar source also need 
to be addressed. Therefore, NMFS does not believe it is beneficial to 
adopt these ``emerging'' monitoring technologies based on their current 
stages of research and development.
    NMFS also considered AWL's suggestion of using scout vessels for 
monitoring marine mammals beyond the visual field where they can be 
detected by the source vessel. However, since the modeled exclusion 
zones at received levels of 180 and 190 dB re 1 [mu]Pa extend out to 
approximately 50 and 190 m (164 and 623 ft), respectively, NMFS 
determined that these distances are within the visual ranges that can 
be reliably detected by protected species observers (PSOs) onboard the 
source vessel. Therefore, NMFS does not believe it is beneficial to 
have additional scout vessels for marine mammal monitoring for this 
particular survey. Furthermore, deploying additional vessels in the 
vicinity of Statoil's proposed survey area would only increase 
anthropogenic impacts to the environment by introducing additional 
vessel noise into the water column. Concerning the manned aircraft 
survey, NMFS typically does not require this measure in the Chukchi Sea 
because it has been determined to be impracticable due to lack of 
adequate landing facilities and the prevalence of fog and other 
inclement weather in that area. This could potentially result in an 
inability to return to the airport of origin, thereby resulting in 
safety concerns.
    NMFS recognizes the limitations of visual monitoring in darkness 
and other inclement weather conditions. Therefore, in Statoil's IHA, 
NMFS requires that no seismic airgun can be ramped up when the entire 
exclusion zones are not visible (i.e., darkness or poor weather 
conditions). However, Statoil's operations will occur in an area where 
periods of darkness do not begin until early September. Beginning in 
early September, there will be approximately 1-3 hours of darkness each 
day, with periods of darkness increasing by about 30 min each day. By 
the end of the survey period, there will be approximately 8 hours of 
darkness each day. These conditions provide PSOs favorable monitoring 
conditions for most of the time.

Subsistence Issues

    Comment 9: AEWC states that NMFS failed to consider adequately the 
potential impacts to the fall subsistence hunt of bowhead whales in 
Chukchi Sea villages. Over the past several years, worsening ice 
conditions have made it more dangerous and difficult for whale captains 
and their crews to carry out the

[[Page 46735]]

larger spring bowhead whale hunt. Because of the changing conditions, 
crews from Wainwright, Point Hope and Point Lay have all been 
conducting fall hunts in an effort to provide for their communities and 
meet their allotted quotas. Last year, Wainwright landed a bowhead 
whale for the first time during the fall, which provided critical food 
for the community and served as a great source of pride and 
celebration.
    Response: NMFS does not agree with AEWC's contention that it failed 
to adequately consider impacts to the fall subsistence hunt. The 
potential impacts from the proposed Statoil survey were fully analyzed 
and addressed in both the Federal Register notice for the proposed IHA 
(76 FR 30110; May 24, 2011) and in the SEA. The proposed survey area is 
~160 km (~100 mi) northwest of Wainwright offshore. Based on the small 
scale of the proposed shallow hazards survey, the radius of the modeled 
160 dB isopleths is 2.25 km (1.4 mi) from the source, and the 120 dB 
isopleths is about 39 km (24 mi) from the source. Therefore, the area 
where the received level could reach 160 dB is approximately 140 km (87 
mi) offshore. Subsistence whaling typically occurs nearshore. In the 
Chukchi Sea region, the fall hunt is generally conducted in an area 
that extends 16 km (10 mi) west of Barrow to 48 km (30 mi) north of 
Barrow. This is also confirmed by AEWC in its comment letter that 
``[s]ubsistence hunters have a limited hunting range and prefer to take 
whales close to shore so as to avoid hauling a harvested whale a long 
distance over which the whale could spoil. During the fall, however, 
subsistence hunters in the Chukchi Sea will pursue bowhead whales as 
far as 50 miles (80 km) from the coast in small, fiberglass boats.'' 
Therefore, it is highly unlikely that the fall subsistence hunt could 
be affected given the industry activities would occur much further 
offshore.

NEPA Concerns

    Comment 10: AWL notes that NMFS is preparing a Programmatic EIS 
(PEIS), and that without a final EIS, additional oil and gas 
exploration in the Chukchi Sea is especially problematic given the 
critical information gaps that still exist today. AWL states that 
without information on the seasonal presence and distribution patterns 
of marine mammals, the agency would find it challenging to meet its 
obligations under the MMPA. AWL states that NMFS should refrain from 
issuing additional authorizations until more is known.
    Response: While the Final EIS is still being developed, NMFS 
conducted a thorough analysis of the affected environment and 
environmental consequences from seismic surveys in the Arctic in 2010 
and prepared the 2010 EA specific to two open-water seismic activities 
by Shell and Statoil. For the issuance of an IHA to Statoil for its 
2011 open-water shallow hazards survey, NMFS has determined that the 
information contained in the 2010 EA is adequate and that no 
significant changes relating to the environment and potential impacts 
from human activities have resulted since the 2010 EA, and that 
Statoil's proposed 2011 open-water shallow hazards surveys are 
essentially the same as the activities analyzed in the 2010 EA. 
Therefore, the 2010 EA is incorporated by reference in the 2011 SEA for 
the issuance of an IHA to Statoil for their open-water shallow hazards 
surveys in 2011.
    While the analysis contained in the Final EIS will apply more 
broadly to Arctic oil and gas operations, NMFS' issuance of an IHA to 
Statoil for the taking of several species of marine mammals incidental 
to conducting its open-water shallow hazards survey in the Chukchi Sea 
in 2011, as analyzed in the SEA, is not expected to significantly 
affect the quality of the human environment. Statoil's surveys are not 
expected to significantly affect the quality of the human environment 
because of the limited duration and scope of operations. Additionally, 
the SEA and the 2010 EA contained a full analysis of cumulative 
impacts.

Miscellaneous Issues

    Comment 11: AEWC states that in the past, they have remained in 
close communication with Statoil in the hopes that Statoil would be 
able to reach agreement with their whaling captains on a set of 
mitigation measures to protect subsistence whaling activities, but 
Statoil has been unwilling to enter into a Conflict Avoidance Agreement 
(CAA) with the impacted communities. In the absence of the signed CAA, 
AEWC requests that NMFS adopt, as mandatory requirements set forth in 
the IHA, the mitigation measures found in Titles II (Open Water Season 
Communications) and V (Avoiding Conflicts During the Open Water Season) 
of the 2011 CAA, which is attached with the AEWC comment letter.
    Response: As NMFS has mentioned previously, the signing of a CAA is 
not a requirement to obtain an IHA. The CAA is a document that is 
negotiated between and signed by the industry participant, AEWC, and 
the Village Whaling Captains' Associations. NMFS has no role in the 
development or execution of this agreement. Although the contents of a 
CAA may inform NMFS' no unmitigable adverse impact determination for 
bowhead and beluga whales, the signing of it is not a requirement. 
While a CAA has not been signed and a final version agreed to by 
industry participants, AEWC, and the Village Whaling Captains' 
Associations has not been provided, NMFS was provided with a copy of 
the version ready for signature by AEWC. NMFS has reviewed the CAA and 
included several measures from Titles II and V of the document which 
relate to marine mammals and avoiding conflicts with subsistence hunts 
in the IHA. Some of the conditions which have been added to the IHA 
include: (1) Avoiding concentrations of whales and reducing vessel 
speed when near whales; (2) conducting sound source verification 
measurements; and (3) participating in the Communication Centers. 
Despite the lack of a signed CAA for 2011 activities, NMFS is confident 
that the measures contained in the IHA (some of which were taken 
directly from the 2011 CAA) will ensure no unmitigable adverse impact 
to subsistence users.
    In addition, Statoil has agreed to utilize the Wainwright 
communication center (Com-Center) in order to communicate with 
subsistence vessels during its 2011 operations. The Com-Center will be 
staffed by Inupiat operators where practicable. The Com-Center will be 
operated twenty-four (24) hours per day during the 2011 subsistence 
bowhead whale hunt. The Com-Center will have an Inupiat operator on 
duty 24 hours per day from August 15 until the end of the 2011 
subsistence bowhead whale hunt and during Statoil's 2011 activities in 
the Chukchi Sea. The Com-Center will be managed and overseen by the 
Olgoonik-Fairweather JV. The Com-Center operators will be available to 
receive radio and telephone calls and to call vessels.
    Following the completion of the 2011 Chukchi Sea open-water season 
and prior to the 2012 Preseason Introduction Meetings, Statoil, if 
requested by the AEWC or the Whaling Captains' Association of each 
village, will host a meeting in each of the following villages: 
Wainwright, Pt. Lay, Pt. Hope, and Barrow (or a joint meeting of the 
whaling captains from all of these villages if the whaling captains 
agree to a joint meeting) to review the results of the 2011 operations 
and to discuss any concerns residents of those villages might have 
regarding the operations. To the extent possible, the meetings will 
include the PSOs stationed on Statoil's vessels in the Chukchi Sea.

[[Page 46736]]

    In summary, the measures that Statoil has taken, and will take, 
under the POC and Marine Mammal Monitoring and Mitigation Plan (4MP) 
are similar to the measures identified in the draft CAA provided by 
AEWC. Below, Statoil and NMFS identify the key conflict-avoidance 
provisions of the CAA, and identify the corresponding provisions of the 
POC, 4MP, and the Participation Agreement focused on minimizing impacts 
to the environment and subsistence resources in the Chukchi Sea.
    Regarding AEWC's request for NMFS to adopt certain sections of the 
2011 CAA as the mitigation measures (i.e., Title II and Title V), NMFS 
carefully reviewed these sections and found that they are within the 
mitigation measures NMFS prescribed to Statoil under the IHA issued for 
mitigating subsistence harvest during Statoil's proposed shallow 
hazards surveys in the Chukchi Sea during the 2011 open-water season. 
However, these sections also contain requirements that NMFS does not 
believe are pertinent to Statoil's proposed 2011 open-water shallow 
hazards surveys. For instance, the draft CAA calls for funding of Com-
Centers and to provide communication equipment in Deadhorse and 
Kaktovik, which are villages on the coast of the Beaufort Sea, far away 
from Statoil's planned Chukchi Sea operations. Therefore, NMFS does not 
believe it is appropriate to adopt these sections of the draft CAA in 
their entirety as mitigation measures for subsistence.

Monitoring Plan Peer Review

    The MMPA requires that monitoring plans be independently peer 
reviewed ``where the proposed activity may affect the availability of a 
species or stock for taking for subsistence uses'' (16 U.S.C. 
1371(a)(5)(D)(ii)(III)). Regarding this requirement, NMFS' implementing 
regulations state, ``Upon receipt of a complete monitoring plan, and at 
its discretion, [NMFS] will either submit the plan to members of a peer 
review panel for review or within 60 days of receipt of the proposed 
monitoring plan, schedule a workshop to review the plan'' (50 CFR 
216.108(d)).
    NMFS convened an independent peer review panel to review Statoil's 
Marine Mammal Monitoring and Mitigation Plan (4MP) for Shallow Hazards 
and Site Clearance Surveys and Geotechnical Soil Investigations in the 
Alaskan Chukchi Sea, 2011. The panel met on March 9, 2011, and provided 
their final report to NMFS on April 27, 2011. The full panel report can 
be viewed at: http://www.nmfs.noaa.gov/pr/pdfs/permits/openwater/peer_review_report2011.pdf.
    NMFS provided the panel with Statoil's 4MP and asked the panel to 
address the following questions and issues for Statoil's plan:
    (1) Are the applicant's stated objectives the most useful for 
understanding impacts on marine mammals and otherwise accomplishing the 
goals stated in the paragraph above?
    (2) Are the applicant's stated objectives able to be achieved based 
on the methods described in the plan?
    (3) Are there techniques not proposed by the applicant, or 
modifications to the techniques proposed by the applicant, that should 
be considered for inclusion in the applicant's monitoring program to 
better accomplish the goals stated above?
    (4) What is the best way for an applicant to present their data and 
results (formatting, metrics, graphics, etc.) in the required reports 
that are to be submitted to NMFS?
    Section 4 of the report contains recommendations that the panel 
members felt were applicable to all of the monitoring plans that they 
reviewed this year. Section 5.1 of the report contains recommendations 
specific to Statoil's 2011 shallow hazards survey monitoring plan. 
Specifically, for the general recommendations, the panel commented on 
issues related to: (1) Acoustic effects of oil and gas exploration--
assessment and mitigation; (2) aerial surveys; (3) marine mammal 
observers; (4) visual near-field monitoring; (5) visual far-field 
monitoring; (6) baseline biological and environmental information; (7) 
comprehensive ecosystem assessments and cumulative impacts; (8) 
duplication of seismic survey effort; (9) improving take estimates and 
statistical inference into effects of the activity; and (10) improving 
the peer-review process.
    NMFS has reviewed the report and evaluated all recommendations made 
by the panel. NMFS has determined that there are several measures that 
Statoil can incorporate into its 2011 open-water shallow hazards 
surveys 4MP to improve it. Additionally, there are other 
recommendations that NMFS has determined would also result in better 
data collection and could potentially be implemented by oil and gas 
industry applicants, but which likely could not be implemented for the 
2011 open-water season due to technical issues (see below). While it 
may not be possible to implement those changes this year, NMFS believes 
that they are worthwhile and appropriate suggestions that may require a 
bit more time to implement, and Statoil should consider incorporating 
them into future monitoring plans should Statoil decide to apply for 
IHAs in the future.
    The following subsections lay out measures that NMFS recommends for 
implementation as part of the 2011 open-water shallow hazards surveys 
4MP and those that are recommended for future programs, as well as 
recommendations for future MMPA authorization applications and 
presentations at future Open Water Meetings. The panel recommendations 
determined by NMFS that are appropriate for inclusion in the 2011 
program have been discussed with Statoil and are included in the IHA.

Recommendations for Inclusion in the 2011 4MP and IHA

     Section 4.3 of the report contains several recommendations 
regarding marine mammal observers (PSOs). NMFS agrees that the 
following measures should be incorporated into the 2011 Monitoring 
Plan:
    [cir] PSOs record additional details about unidentified marine 
mammal sightings, such as ``blow only'', mysticete with (or without) a 
dorsal fin, ``seal splash'', etc. That information should also be 
included in 90-day and final reports.
     In Section 4.7, panelists included a section regarding the 
need for a more robust and comprehensive means of assessing the 
collective or cumulative impact of many of the varied human activities 
that contribute noise into the Arctic environment. Specifically, for 
data analysis and integration, the panelists recommended, and NMFS 
agrees, that the following recommendations be incorporated into the 
2011 program:
    [cir] To better assess impacts to marine mammals, data analysis 
should be separated into periods when a seismic airgun array (or a 
single mitigation airgun) is operating and when it is not. Final and 
comprehensive reports to NMFS should summarize and plot:
    [dec221] Data for periods when a seismic array is active and when 
it is not; and
    [dec221] The respective predicted received sound conditions over 
fairly large areas (tens of km) around operations.
    [cir] To better understand the potential effects of oil and gas 
activities on marine mammals and to facilitate integration among 
companies and other researchers, the following data should be obtained 
and provided electronically in the final and comprehensive reports:
    [dec221] The location and time of each aerial or vessel-based 
sighting or acoustic detection;
    [dec221] Position of the sighting or acoustic detection relative to 
ongoing operations

[[Page 46737]]

(i.e., distance from sightings to seismic operation, drilling ship, 
support ship, etc.), if known;
    [dec221] The nature of activities at the time (e.g., seismic on/
off);
    [dec221] Any identifiable marine mammal behavioral response 
(sighting data should be collected in a manner that will not detract 
from the PSO's ability to detect marine mammals); and
    [dec221] Any adjustments made to operating procedures.
     In Section 4.9, the panelists discussed improving take 
estimates and statistical inference into effects of the activities. 
NMFS agrees that the following measures should be incorporated into the 
2011 Monitoring Plan:
    [cir] Reported results from all hypothesis tests should include 
estimates of the associated statistical power when practicable.
    [cir] Estimate and report uncertainty in all take estimates. 
Uncertainty could be expressed by the presentation of confidence 
limits, a minimum-maximum, posterior probability distribution, etc.; 
the exact approach would be selected based on the sampling method and 
data available.
     Section 5.1 of the report contains recommendations 
specific to Statoil's 2011 shallow hazards survey monitoring plan. Of 
the recommendations presented in this section, NMFS has determined that 
the following should be implemented for the 2011 season:
    [cir] Conduct sound source verification for the sub-bottom 
profilers.
    [cir] The report should clearly compare authorized takes to the 
level of actual estimated takes.
    [cir] As a starting point for integrating different data sources, 
Statoil should present their 2010 and 2011 data by plotting acoustic 
detections from bottom-mounted hydrophones and visual detections from 
PSOs on a single map.
     In addition, the panelists included a list of general 
recommendations from the 2010 Peer-review Panel Report to be 
implemented by operators in their 2011 open-water season activities. 
NMFS agrees that the following recommendations should be implemented in 
Statoil's 2011 monitoring plan:
    [cir] Observers should be trained using visual aids (e.g., videos, 
photos), to help them identify the species that they are likely to 
encounter in the conditions under which the animals will likely be 
seen.
    [cir] Observers should understand the importance of classifying 
marine mammals as ``unknown'' or ``unidentified'' if they cannot 
identify the animals to species with confidence. In those cases, they 
should note any information that might aid in the identification of the 
marine mammal sighted (and this information should be included in the 
report). For example, for an unidentified mysticete whale, the 
observers should record whether the animal had a dorsal fin.
    [cir] Observers should attempt to maximize the time spent looking 
at the water and guarding the safety radii. They should avoid the 
tendency to spend too much time evaluating animal behavior or entering 
data on forms, both of which detract from their primary purpose of 
monitoring the safety zone.
    [cir] ``Big eye'' binoculars (e.g., 25 x 150 power) should be used 
from high perches on large, stable platforms. They are most useful for 
monitoring impact zones that extend beyond the effective line of sight. 
With two or three observers on watch, the use of big eyes should be 
paired with searching by naked eye, the latter allowing visual coverage 
of nearby areas to detect marine mammals. When a single observer is on 
duty, the observer should follow a regular schedule of shifting between 
searching by naked eye, low-power binoculars, and big-eye binoculars 
based on the activity, the environmental conditions, and the marine 
mammals of concern.
    [cir] Observers should use the best possible positions for 
observing (e.g., outside and as high on the vessel as possible), taking 
into account weather and other working conditions.
    [cir] Observer teams should include Alaska Natives, and all 
observers should be trained together. Whenever possible, new observers 
should be paired with experienced observers to avoid situations where 
lack of experience impairs the quality of observations.
    [cir] Conduct efficacy testing of night-vision binoculars and other 
such instruments to improve near-field monitoring under Arctic 
conditions.
    [cir] To help evaluate the utility of ramp-up procedures, PSOs 
shall record, analyze, and report their observations during any ramp-up 
period.
    [cir] PSOs should carefully document visibility during observation 
periods so that total estimates of take can be corrected accordingly.

Recommendations for Inclusion in Future Monitoring Plans

    In Section 4.7 of the report, the panelists stated that advances in 
integrating data from multiple platforms through the use of 
standardized data formats are needed to increase the statistical power 
to assess potential effects. Therefore, the panelists recommended that 
industry examine this issue and jointly propose one or several data 
integration methods to NMFS at the Open Water Meeting in 2012. NMFS 
concurs with the recommendation and encourages Statoil to collaborate 
with other companies to discuss data integration methods and to present 
the results of those discussions at the 2012 Open Water Meeting.
    In Section 4.7, the panel also recommended that Statoil's reports 
include sightability curves (detection functions) for distance-based 
analyses to help evaluate the effectiveness of PSOs and more 
effectively estimate take. NMFS discussed this requirement with Statoil 
on a technical basis and realizes that in most circumstances there are 
often too few sightings of individual species recorded during a single 
project to allow reliable estimates of sightability curves. Therefore, 
sightability curves from previous comprehensive reports (where multi-
year or multi-project data have been pooled to achieve adequate sample 
sizes) are often used and referenced in 90-day reports. Whenever future 
monitoring data present enough data from a single project, sightability 
curves will be provided in the report.
    In Section 5.1, the panel recommended that Statoil consider other 
new technologies (i.e., underwater vehicles, satellite monitoring, 
etc.) to assess far-field monitoring. The panel also recommended 
investigating other methods for far-field monitoring (e.g., unmanned 
systems or scout vessels) to be implemented upon approval by NMFS. NMFS 
agrees that new technologies should be considered to increase our 
current knowledge regarding marine mammals that could be affected 
beyond the line of sight from the vessel platform and will discuss this 
issue with the industry at the 2012 Open Water Meeting.
    The panel also recommended using the cluster array to localize 
whale calls and evaluate the effects of sound on calling animal 
distribution. However, based on the limited usefulness of data 
collected on the cluster array last year (2010 open-water season), the 
areas where the recording arrays were previously used for localizing 
whales have been expanded to cover a much larger area in 2011, which 
also include the Hanna Shoal area to potentially capture more 
information on whale migration.
    If more recording arrays are available in the future, NMFS will 
work with Statoil to deploy these arrays within the proposed project 
area for localizing calling whales.

[[Page 46738]]

Recommendations for Future Applications and Open Water Meetings

    In Section 3, panelists recommended that companies specifically 
report the changes they made in their operations as a result of the 
previous years' panel recommendations. These should be highlighted in 
the verbal presentations at the Open Water Meeting, discussed directly 
with the review panel, and detailed in the 90-day reports (and final 
reports, if appropriate). NMFS concurs with this recommendation and 
requests that Statoil include this information in their 90-day report 
submitted at the conclusion of operations and provide the information 
in their presentation at the 2012 Open Water Meeting.
    In Section 4.1, panelists made a recommendation that IHA holders 
should report estimates of the spatio-temporal distributions of 
acoustic levels. This could include reporting levels as low as the 120 
dB level. NMFS agrees that applicants should include this information 
in future MMPA application requests.
    In Section 4.7, panelists included a recommendation that could be 
helpful for the presentation of data at future Open Water Meetings. To 
allow visualization and interpretation of the complex field of 
anthropogenic activities and distributions and movements of marine 
mammals, the final and comprehensive reports required by the IHA should 
provide all spatial data on figures that depict the locations of the 
principal sound sources. This could be represented by a diagram in 
which all PSO sightings (vessel-based and aerial) and acoustic 
detections are plotted relative to their distance and bearing from a 
specific sound source. Alternatively, it could be depicted in a map of 
the region, showing the operation area, tracklines of vessels and 
aircraft (if applicable), PSO sightings (vessel-based and aerial), and 
acoustic detections. To facilitate understanding of both the spatial 
and temporal aspects of the activity and marine mammal responses, these 
figures would ideally be animated, showing industry activities and 
sightings or acoustic detections changing through time. Whenever 
ancillary biological data (e.g., tagging, acoustic, broad-scale aerial 
survey) are available that are coincident in space and time with the 
activity, they should be included in these figures. NMFS encourages 
Statoil to consider this recommendation when preparing figures and 
videos for reports and the Open Water Meeting.

Recommendations From 2010 Peer-Review Panel for Inclusion in Future 
Monitoring Plans

    Section 3.5 of the 2010 Peer-review Panel report recommends methods 
for conducting comprehensive monitoring of a large-scale seismic 
operation. The panelists recommend adding a tagging component to 
monitoring plans. ``Tagging of animals expected to be in the area where 
the survey is planned also may provide valuable information on the 
location of potentially affected animals and their behavioral responses 
to industrial activities. Although the panel recognized that such 
comprehensive monitoring might be difficult and expensive, such an 
effort (or set of efforts) reflects the complex nature of the challenge 
of conducting reliable, comprehensive monitoring for seismic or other 
relatively-intense industrial operations that ensonify large areas of 
ocean''. While this particular recommendation is not feasible for 
implementation in 2011, NMFS recommends that Statoil consider adding a 
tagging component to future monitoring plans should Statoil decide to 
conduct such activities in future years.
    Finally, the panel recommended that sightings be entered and 
archived in a way that enables immediate geospatial depiction to 
facilitate operational awareness and analysis of risks to marine 
mammals. Real-time monitoring is especially important in areas of 
seasonal migration or influx of marine mammals. NMFS worked with 
Statoil and the panel to identify certain software packages for real-
time data entry, mapping, and analysis available for this purpose, but 
it does not seem that a commercially viable software system is 
available at this time.

Description of Marine Mammals in the Area of the Specified Activity

    Nine cetacean and four seal species could occur in the general area 
of the site clearance and shallow hazards survey. The marine mammal 
species under NMFS' jurisdiction most likely to occur near operations 
in the Chukchi Sea include four cetacean species: Beluga whale 
(Delphinapterus leucas), bowhead whale (Balaena mysticetus), gray whale 
(Eschrichtius robustus), and harbor porpoise (Phocoena phocoena), and 
three seal species: Ringed (Phoca hispida), spotted (P. largha), and 
bearded seals (Erignathus barbatus). The marine mammal species that is 
likely to be encountered most widely (in space and time) throughout the 
period of the planned site clearance and shallow hazards surveys is the 
ringed seal.
    Other marine mammal species that have been observed in the Chukchi 
Sea but are less frequent or uncommon in the project area include 
narwhal (Monodon monoceros), killer whale (Orcinus orca), fin whale 
(Balaenoptera physalus), minke whale (B. acutorostrata), humpback whale 
(Megaptera novaeangliae), and ribbon seal (Histriophoca fasciata). 
These species could occur in the project area, but each of these 
species is uncommon or rare in the area and relatively few encounters 
with these species are expected during the proposed shallow hazards 
survey. The narwhal occurs in Canadian waters and occasionally in the 
Beaufort Sea, but it is rare there and is not expected to be 
encountered. There are scattered records of narwhal in Alaskan waters, 
including reports by subsistence hunters, where the species is 
considered extralimital (Reeves et al. 2002).
    The bowhead, fin, and humpback whales are listed as ``endangered'' 
under the Endangered Species Act (ESA) and as depleted under the MMPA. 
Certain stocks or populations of gray, beluga, and killer whales and 
spotted seals are listed as endangered or proposed for listing under 
the ESA; however, none of those stocks or populations occur in the 
proposed activity area. Additionally, the ribbon seal is considered a 
``species of concern'' under the ESA. On December 10, 2010, NMFS 
published a notification of proposed threatened status for subspecies 
of the ringed seal (75 FR 77476) and a notification of proposed 
threatened and not warranted status for subspecies and distinct 
population segments of the bearded seal (75 FR 77496) in the Federal 
Register. Neither species is considered depleted under the MMPA. The 
polar bear (which is listed as threatened under the ESA) and walrus 
also occur in the Chukchi Sea. However, both species are under the 
jurisdiction of the U.S. Fish and Wildlife Service and are therefore 
not discussed further in this document.
    Statoil's application contains 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 2010 SAR is available at: http://www.nmfs.noaa.gov/pr/pdfs/sars/ak2010.pdf.

[[Page 46739]]

Potential Effects of the Specified Activity on Marine Mammals

    Operating active acoustic sources such as an airgun array has the 
potential for adverse effects on marine mammals.

Potential Effects of Airgun Sounds on Marine Mammals

    The effects of sounds from airgun 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. 
The Notice of Proposed IHA (76 FR 30110; May 24, 2011) included a 
discussion of the effects of airguns on marine mammals, which is not 
repeated here. That discussion did not take into consideration the 
monitoring and mitigation measures proposed by Statoil and NMFS. No 
cases of temporary threshold shift (TTS) are expected as a result of 
Statoil's activities given the small size of the source, the strong 
likelihood that baleen whales (especially migrating bowheads) would 
avoid the approaching airguns (or vessel) before being exposed to 
levels high enough for there to be any possibility of TTS, and the 
mitigation measures required to be implemented during the survey 
described later in this document. Based on the fact that the sounds 
produced by Statoil's operations are unlikely to cause TTS in marine 
mammals, it is extremely unlikely that permanent hearing impairment 
would result. No injuries or mortalities are anticipated as a result of 
Statoil's operations, and none are authorized to occur. Only Level B 
harassment is anticipated as a result of Statoil's activities.

Potential Effects From Active Sonar Equipment on Marine Mammals

    Several active acoustic sources other than the four 10 in\3\ airgun 
have been proposed for Statoil's 2011 open water shallow hazards survey 
in the Chukchi Sea. The specifications of this sonar equipment (source 
levels and frequency ranges) were provided in the Notice of Proposed 
IHA (76 FR 30110; May 24, 2011). In general, the potential effects of 
this equipment on marine mammals are similar to those from the airgun, 
except the magnitude of the impacts is expected to be much less due to 
the lower intensity and higher frequencies. In some cases, due to the 
fact that the operating frequencies of some of this equipment (e.g., 
Multi-beam echosounder: frequency at 200-400 kHz) are above the hearing 
ranges of marine mammals, they are not expected to have any impacts to 
marine mammals. The Notice of Proposed IHA (76 FR 30110; May 24, 2011) 
contains a discussion of impacts to marine mammals from vessel sounds, 
which is not repeated here.

Anticipated Effects on Habitat

    The primary potential impacts to marine mammals and other marine 
species are associated with elevated sound levels produced by airguns 
and other active acoustic sources. However, other potential impacts to 
the surrounding habitat from physical disturbance are also possible.

Potential Impacts on Prey Species

    With regard to fish as a prey source for cetaceans and pinnipeds, 
fish are known to hear and react to sounds and to use sound to 
communicate (Tavolga et al. 1981) and possibly avoid predators (Wilson 
and Dill 2002). Experiments have shown that fish can sense both the 
strength and direction of sound (Hawkins 1981). Primary factors 
determining whether a fish can sense a sound signal, and potentially 
react to it, are the frequency of the signal and the strength of the 
signal in relation to the natural background noise level.
    The level of sound at which a fish will react or alter its behavior 
is usually well above the detection level. Fish have been found to 
react to sounds when the sound level increased to about 20 dB above the 
detection level of 120 dB (Ona 1988); however, the response threshold 
can depend on the time of year and the fish's physiological condition 
(Engas et al. 1993). In general, fish react more strongly to pulses of 
sound rather than a continuous signal (Blaxter et al. 1981), and a 
quicker alarm response is elicited when the sound signal intensity 
rises rapidly compared to sound rising more slowly to the same level.
    Investigations of fish behavior in relation to vessel noise (Olsen 
et al. 1983; Ona 1988; Ona and Godo 1990) have shown that fish react 
when the sound from the engines and propeller exceeds a certain level. 
Avoidance reactions have been observed in fish such as cod and herring 
when vessels approached close enough that received sound levels are 110 
dB to 130 dB (Nakken 1992; Olsen 1979; Ona and Godo 1990; Ona and 
Toresen 1988). However, other researchers have found that fish such as 
polar cod, herring, and capelin are often attracted to vessels 
(apparently by the noise) and swim toward the vessel (Rostad et al. 
2006). Typical sound source levels of vessel noise in the audible range 
for fish are 150 dB to 170 dB (Richardson et al. 1995).
    Some mysticetes, including bowhead whales, feed on concentrations 
of zooplankton. Some feeding bowhead whales may occur in the Alaskan 
Beaufort Sea in July and August, and others feed intermittently during 
their westward migration in September and October (Richardson and 
Thomson [eds.] 2002; Lowry et al. 2004). However, by the time most 
bowhead whales reach the Chukchi Sea (October), they will likely no 
longer be feeding, or if it occurs it will be very limited. A reaction 
by zooplankton to a seismic impulse would only be relevant to whales if 
it caused concentrations of zooplankton to scatter. Pressure changes of 
sufficient magnitude to cause that type of reaction would probably 
occur only very close to the source. Impacts on zooplankton behavior 
are predicted to be negligible, and that would translate into 
negligible impacts on feeding mysticetes. Thus, the activity is not 
expected to have any habitat-related effects that could cause 
significant or long-term consequences for individual marine mammals or 
their populations.

Mitigation Measures

    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 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.
    For Statoil's open-water shallow hazards survey in the Chukchi Sea, 
Statoil worked with NMFS and agreed upon the following mitigation 
measures to minimize the potential impacts to marine mammals in the 
project vicinity as a result of the shallow hazards survey activities.
    As part of the application, Statoil submitted to NMFS a Marine 
Mammal Monitoring and Mitigation Program (4MP) for its open-water 
shallow hazards survey in the Chukchi Sea during the 2011 open-water 
season. The objectives of the 4MP are:
     To ensure that disturbance to marine mammals and 
subsistence hunts is minimized and all permit stipulations are 
followed,
     To document the effects of the proposed survey activities 
on marine mammals, and

[[Page 46740]]

     To collect baseline data on the occurrence and 
distribution of marine mammals in the study area.
    The 4MP has been modified based on comments received from the peer 
review panel (see the ``Monitoring Plan Peer Review'' section earlier 
in this document).
    For Statoil's 2011 open-water shallow water hazards surveys in the 
Chukchi Sea, the following mitigation measures are required.

(1) Sound Source Measurements

    Previous measurements of similar airgun arrays in the Chukchi Sea 
were used to model the distances at which received levels are likely to 
fall below 120, 160, 180, and 190 dB re 1 [mu]Pa (rms) from the planned 
airgun sources. These modeled distances will be used as temporary 
exclusion radii until measurements of the airgun sound source are 
conducted. The measurements will be made at the beginning of the field 
season, and the measured radii used for the remainder of the survey 
period.
    The objectives of the sound source verification measurements 
planned for 2011 in the Chukchi Sea will be to measure the distances at 
which broadband received levels reach 190, 180, 170, 160, and 120 
dBrms re 1 [mu]Pa for the airgun configurations that may be 
used during the survey activities. The configurations will include at 
least the full array (4 x 10 in\3\) and the operation of a single 10 
in\3\ airgun that will be used during power downs or very shallow 
penetration surveys. The measurements of airgun sounds will be made by 
an acoustics contractor at the beginning of the survey. The distances 
to the various radii will be reported as soon as possible after 
recovery of the equipment. The primary radii of concern will be the 190 
and 180 dB exclusion radii for pinnipeds and cetaceans, respectively, 
and the 160 dB disturbance radii. In addition to reporting the radii of 
specific regulatory concern, nominal distances to other sound isopleths 
down to 120 dBrms will be reported in increments of 10 dB. 
Sound levels during soil investigation operations will also be 
measured. However, source levels are not expected to be strong enough 
to require mitigation actions at the 190 dB or 180 dB levels.
    Data will be previewed in the field immediately after download from 
the hydrophone instruments. An initial sound source analysis will be 
supplied to NMFS and the vessel within 120 hours of completion of the 
measurements, if possible. The report will indicate the distances to 
sound levels based on fits of empirical transmission loss formulae to 
data in the endfire and broadside directions. A more detailed report 
will be submitted to NMFS as part of the 90-day report following 
completion of the acoustic program.

(2) Exclusion Zones

    Under current NMFS guidelines, ``exclusion zones'' for marine 
mammal exposure to impulse sources are customarily defined as 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 criteria are based on an assumption 
that SPLs received at levels lower than these will not injure these 
animals or impair their hearing abilities, but that at higher levels 
they might have some such effects. Disturbance or behavioral effects to 
marine mammals from underwater sound may occur after exposure to sound 
at distances greater than the exclusion zones (Richardson et al. 1995).
    Initial exclusion and disturbance zones for the sound levels 
produced by the planned airgun configurations have been estimated 
(Table 1). These zones will be used for mitigation purposes until 
results of direct measurements are available early during the 
exploration activities. The proposed surveys will use an airgun source 
composed of four 10-in\3\ airguns (total discharge volume of 40 in\3\) 
and a single 10 in\3\ airgun. Underwater sound propagation from a 
similar 4 x 10-in\3\ airgun cluster and single 10 in\3\ was measured in 
2009 (Reiser et al. 2010). Those measurements resulted in 90th 
percentile propagation loss equations of RL = 218.0 - 17.5LogR - 
0.00061R for the 4 x 10 in\3\ airgun cluster and RL = 204.4 - 16.0LogR 
- 0.00082R for the single 10 in\3\ airgun (where RL = received level 
and R = range). The estimated distances for the 2011 activities are 
based on a 25% increase over 2009 results (Table 1).
    In addition to the site surveys, Statoil plans to use a dedicated 
vessel to conduct geotechnical soil investigations. Sounds produced by 
the vessel and soil investigation equipment are not expected to be 
above 180 dB (rms). Therefore, mitigation related to acoustic impacts 
from these activities is not expected to be necessary.
    An acoustics contractor will perform direct measurements of the 
received levels of underwater sound versus distance and direction from 
the airguns and soil investigation vessel using calibrated hydrophones. 
The acoustic data will be analyzed as quickly as reasonably practicable 
in the field and used to verify and adjust the exclusion zones. The 
field report will be made available to NMFS and the PSOs within 120 hrs 
of completing the measurements. The mitigation measures to be 
implemented at the 190 and 180 dB sound levels will include power downs 
and shut downs as described below.

  Table 1--Distances to Specified Received Levels Measured From a 4 x 10 In\3\ Airgun Cluster and a Single 10-
 in\3\ Airgun on the Burger Prospect in 2009 as Reported by Reiser et al. (2010). The 2011 ``Pre-SSV'' Distances
    are a Precautionary 25% Increase Above the Reported 2009 Results and Will Be Used by PSOs for Mitigation
                                   Purposes Until an SSV is Completed in 2011
----------------------------------------------------------------------------------------------------------------
                                                                       Distance (m)
                                         -----------------------------------------------------------------------
  Received levels (dB re 1 [mu]Pa rms)       Airgun cluster (4 x 10 in\3\)       Single airgun (1 x 10 in\3\)
                                         -----------------------------------------------------------------------
                                            2009 Results      2011 pre-SSV      2009 Results      2011 pre-SSV
----------------------------------------------------------------------------------------------------------------
190.....................................                39                50                 8                10
180.....................................               150               190                34                45
160.....................................             1,800             2,250               570               715
120.....................................            31,000            39,000            19,000            24,000
----------------------------------------------------------------------------------------------------------------


[[Page 46741]]

(3) Speed and Course Alterations

    If a marine mammal is detected outside the applicable exclusion 
zone and, based on its position and the relative motion, is likely to 
enter the exclusion 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 streamer arrays, course 
alterations are not typically possible. However, for the smaller airgun 
array and streamer planned during Statoil's 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 applicable exclusion zone. If the 
mammal appears likely to enter the exclusion zone, further mitigative 
actions will be taken, including a power down or shut down of the 
airgun(s).
    In addition, Statoil vessels are required to comply with the 
following conditions concerning their speed with their relation of 
distances to whales:
     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;
     Avoid multiple changes in direction and speed when within 
300 yards (274 m) of whales; and
     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) Power Downs

    A power down for immediate mitigation purposes is the immediate 
reduction in the number of operating airguns such that the exclusion 
zones of the 190 dBrms and 180 dBrms areas are 
decreased to the extent that an observed marine mammal(s) are not in 
the applicable exclusion zone of the full array. Power downs are also 
used while the vessel turns from the end of one survey line to the 
start of the next. During a power down, one airgun (or some other 
number of airguns less than the full airgun array) continues firing. 
The continued operation of one airgun 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 exclusion zone 
of the full array but is outside the applicable exclusion zone of the 
single mitigation airgun. Likewise, if a mammal is already within the 
exclusion zone when first detected, the airguns will be powered down 
immediately. If a marine mammal is sighted within or about to enter the 
applicable exclusion zone of the single airgun, it too will be shut 
down (see following section).
    Following a power down, operation of the full airgun array will not 
resume until the marine mammal has cleared the exclusion zone. The 
animal will be considered to have cleared the exclusion zone if it:
     Is visually observed to have left the exclusion 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 mysticetes or large odontocetes.

(5) Shut Downs

    The operating airgun(s) will be shut down completely if a marine 
mammal approaches or enters the then-applicable exclusion zone, and a 
power down is not practical or adequate to reduce exposure to less than 
190 or 180 dBrms, as appropriate. In most cases, this means 
the mitigation airgun will be shut down completely if a marine mammal 
approaches or enters the estimated exclusion zone around the single 10 
in\3\ airgun while it is operating during a power down. Airgun activity 
will not resume until the marine mammal has cleared the exclusion zone. 
The animal will be considered to have cleared the exclusion zone as 
described above under power down procedures.
    A shut down of the borehole drilling equipment may be requested by 
PSOs if an animal is sighted approaching the vessel close enough to 
potentially interact with and be harmed by the soil investigation 
operation.

(6) Ramp Ups

    A ramp up of an airgun array provides a gradual increase in sound 
levels and involves a step-wise increase in the number and total volume 
of airguns 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 airguns 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 site survey program, the seismic operator will 
ramp up the airgun cluster slowly. Full ramp ups (i.e., from a cold 
start after a shut down, when no airguns have been firing) will begin 
by firing a single airgun in the array. The minimum duration of a shut-
down period, i.e., without airguns firing, which must be followed by a 
ramp up is typically the amount of time it would take the source vessel 
to cover the 180-dB exclusion zone. Given the small size of the planned 
airgun array, it is estimated that period would be about 1-2 minutes 
based on the modeling results described above and a survey speed of 4 
kts.
    A full ramp up, after a shut down, will not begin until there has 
been a minimum of 30 minutes of observation of the exclusion zone by 
PSOs to ensure that no marine mammals are present. The entire exclusion 
zone must be visible during the 30-minute lead-in to a full ramp up. If 
the entire exclusion zone is not visible, then ramp up from a cold 
start cannot begin. If a marine mammal(s) is sighted within the 
exclusion 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 
exclusion zone or the animal(s) is not sighted for at least 15-30 
minutes: 15 minutes for small odontocetes and pinnipeds, or 30 minutes 
for baleen whales and large odontocetes.
    During turns or brief transits between survey transects, one airgun 
will continue operating. The ramp-up procedure will still be followed 
when increasing the source levels from one airgun to the full 4-airgun 
cluster. However, keeping one airgun firing will avoid the prohibition 
of a cold start during darkness or other periods of poor visibility. 
Through use of this approach, survey operations can resume upon entry 
to a new transect without the 30-minute watch period of the full 
exclusion zone required for a cold start. PSOs will be on duty whenever 
the airguns are firing during daylight and during the 30-min periods 
prior to ramp-ups, as well as during ramp-ups. Daylight will occur for 
24 hr/day until mid-August, so until that date PSOs will automatically 
be observing during the 30-minute period preceding a ramp up. Later in 
the season, PSOs will be called to duty at night to observe prior to 
and during any ramp ups. The survey operator and PSOs will maintain 
records of the times when ramp-ups start and when the airgun arrays 
reach full power.

(7) Mitigation Measures Concerning Baleen Whale Aggregations

    A 160-dB vessel monitoring zone for large whales will be 
established and monitored in the Chukchi Sea during all

[[Page 46742]]

shallow hazards surveys. Whenever a large number of bowhead whales or 
gray whales (12 or more whales of any age/sex class that appear to be 
engaged in a non-migratory, significant biological behavior (e.g., 
feeding, socializing)) are observed during a vessel monitoring program 
within the 160-dB exclusion zone around the survey operations, the 
survey activity will not commence or will shut down, until no more than 
12 whales are present within the 160-dB exclusion zone of shallow 
hazards surveying operations.

(8) Subsistence Mitigation Measures

    Statoil plans to introduce the following mitigation measures, 
plans, and programs to potentially affected subsistence groups and 
communities. These measures, plans, and programs have been effective in 
past seasons of work in the Arctic and were developed in past 
consultations with these communities.
    Statoil will not be entering the Chukchi Sea until early August, so 
there will be no potential conflict with spring bowhead whale or beluga 
subsistence whaling in the polynya zone. Statoil's planned activities 
area is ~100 mi (~161 km) northwest of Wainwright, which reduces the 
potential impact to subsistence hunting activities occurring along the 
Chukchi Sea coast.
    The communication center in Wainwright will be jointly funded by 
Statoil and other operators, and Statoil will routinely call the 
communication center according to the established protocol while in the 
Chukchi Sea. Depending on survey progress, Statoil may perform a crew 
change in the Nome area in Alaska. The crew change will not involve the 
use of helicopters. Statoil does have a contingency plan for a 
potential transfer of a small number of crew via ship-to-shore vessel 
at Wainwright. If this should become necessary, the Wainwright 
communications center will be contacted to determine the appropriate 
vessel route and timing to avoid potential conflict with subsistence 
users.
    Prior to survey activities, Statoil will identify transit routes 
and timing to avoid other subsistence use areas and communicate with 
coastal communities before operating in or passing through these areas.

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;
     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 by NMFS and proposed by the 
independent peer review panel, NMFS has determined that the proposed 
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 Measures

    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.

Monitoring Measures

    The following monitoring measures are required for Statoil's 2011 
open-water shallow hazards surveys in the Chukchi Sea.
(1) Vessel-Based PSOs
    Vessel-based monitoring for marine mammals will be done by trained 
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 airgun 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 by harassment'' as defined by NMFS.
    A sufficient number of PSOs will be required onboard the survey 
vessel to meet the following criteria: (1) 100% 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 Inupiat observers and experienced field 
biologists. An experienced field crew leader will supervise the PSO 
team onboard the survey vessel. The total number of PSOs may decrease 
later in the season as the duration of daylight decreases. Statoil 
currently plans to have 5 PSOs aboard the site survey vessel and 3 PSOs 
aboard the soil investigation vessel, with the potential of reducing 
the number of PSOs later in the season as daylight periods decrease in 
length.
    Crew leaders and most other biologists serving as observers in 2011 
will be individuals with experience as observers during recent seismic 
or shallow hazards monitoring projects in Alaska, the Canadian 
Beaufort, or other offshore areas in recent years.
    Observer teams shall include Alaska Natives, and all observers 
shall be trained together. Whenever possible, new observers shall be 
paired with experienced observers to avoid situations where lack of 
experience impairs the quality of observations.
    Observers will complete a two or three-day training session on 
marine mammal monitoring, to be conducted shortly before the 
anticipated start of the 2011 open-water season. The training 
session(s) will be conducted by qualified marine mammalogists with 
extensive crew-leader experience during previous vessel-based 
monitoring programs. A marine mammal observers' handbook, adapted for 
the specifics of the planned survey program will be reviewed as part of 
the training.
    Primary objectives of the training include:
     Review of the marine mammal monitoring plan for this 
project, including any amendments specified by NMFS in the IHA, by 
USFWS or Bureau of Ocean Energy Management, Regulation and Enforcement 
(BOEMRE), or by other agreements in which Statoil may elect to 
participate;
     Review of marine mammal sighting, identification, and 
distance estimation methods;
     Review of operation of specialized equipment (reticle 
binoculars, night vision devices [NVDs], and GPS system);
     Review of, and classroom practice with, data recording and 
data entry systems, including procedures for

[[Page 46743]]

recording data on marine mammal sightings, monitoring operations, 
environmental conditions, and entry error control. These procedures 
will be implemented through use of a customized computer database and 
laptop computers;
     Review of the specific tasks of the Inupiat Communicator.
    Observers should be trained using visual aids (e.g., videos, 
photos), to help them identify the species that they are likely to 
encounter in the conditions under which the animals will likely be 
seen.
    Observers should attempt to maximize the time spent looking at the 
water and guarding the exclusion radii. They should avoid the tendency 
to spend too much time evaluating animal behavior or entering data on 
forms, both of which detract from their primary purpose of monitoring 
the exclusion zone.
    Observers should use the best possible positions for observing 
(e.g., outside and as high on the vessel as possible), taking into 
account weather and other working conditions.
    The observer(s) will watch for marine mammals from the best 
available vantage point on the survey vessels, typically the bridge. 
The observer(s) will scan systematically with the unaided eye and 7 x 
50 reticle binoculars, supplemented with 20 x 60 image-stabilized Zeiss 
Binoculars or Fujinon 25 x 150 ``Big-eye'' binoculars, and night-vision 
equipment when needed (see below). Personnel on the bridge will assist 
the PSOs in watching for marine mammals.
    Information to be recorded by PSOs will include the same types of 
information that were recorded during recent monitoring programs 
associated with industry activity in the Arctic (e.g., Ireland et al. 
2009). 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;
    (C) The positions of other vessel(s) in the vicinity of the PSO 
location;
    (D) Any identifiable marine mammal behavioral response (sighting 
data should be collected in a manner that will not detract from the 
PSO's ability to detect marine mammals);
    (E) any adjustments made to operating procedures; and
    (F) observations during any ramp-up period.
    Observers should understand the importance of classifying marine 
mammals as ``unknown'' or ``unidentified'' if they cannot identify the 
animals to species with confidence. In those cases, they should note 
any information that might aid in the identification of the marine 
mammal sighted (and this information should be included in the report). 
For example, for an unidentified mysticete whale, the observers should 
record whether the animal had a dorsal fin.
    Additional details about unidentified marine mammal sightings, such 
as ``blow only'', mysticete with (or without) a dorsal fin, ``seal 
splash'', etc., shall be recorded. That information should also be 
included in 90-day and final reports.
    PSOs should carefully document visibility during observation 
periods so that total estimates of take can be corrected accordingly.
    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.

Monitoring at Night and in Poor Visibility

    Night-vision equipment (Generation 3 binocular image intensifiers, 
or equivalent units) will be available for use when/if needed. Past 
experience with NVDs in the Beaufort and Chukchi seas and elsewhere has 
indicated that NVDs are not nearly as effective as visual observation 
during daylight hours (e.g., Harris et al. 1997, 1998; Moulton and 
Lawson 2002).
    Conduct efficacy testing of night-vision binoculars and other such 
instruments to improve near-field monitoring under Arctic conditions 
and compare with the 2010 monitoring results.
(2) Acoustic Monitoring

Sound Source Measurements

    As described above, previous measurements of airguns in the Chukchi 
Sea were used to estimate the distances at which received levels are 
likely to fall below 120, 160, 180, and 190 dBrms from the 
planned airgun sources. These modeled distances will be used as 
temporary exclusion radii until measurements of the airgun sound source 
are conducted. The measurements will be made at the beginning of the 
field season and the measured radii used for the remainder of the 
survey period. An acoustics contractor will use their equipment to 
record and analyze the underwater sounds and write the summary reports 
as described below.
    The objectives of the sound source verification measurements 
planned for 2011 in the Chukchi Sea will be to measure the distances at 
which broadband received levels reach 190, 180, 170, 160, and 120 
dBrms re 1 [micro]Pa for the airgun configurations that may 
be used during the survey activities. The configurations will include 
at least the full array (4 x 10 in\3\) and the operation of a single 10 
in\3\ airgun that will be used during power downs or very shallow 
penetration surveys.

2011 Joint Environmental Studies Program

    Statoil, Shell Offshore, Inc. (Shell), and CPAI are working on 
plans to once again jointly fund an extensive environmental studies 
program in the Chukchi Sea. This program is expected to be coordinated 
by Olgoonik-Fairweather LLC (OFJV) during the 2011 open-water season. 
The environmental studies program is not part of the Statoil site 
survey and soil investigations program, but acoustic monitoring 
equipment is planned to be deployed on and near Statoil leases and will 
therefore collect additional data on the sounds produced by the 2011 
activities. The program components include:
     Acoustics Monitoring,
     Fisheries Ecology,
     Benthic Ecology,
     Plankton Ecology,
     Marine Mammal Surveys,
     Seabird Surveys, and
     Physical Oceanography.
    The planned 2011 program will continue the acoustic monitoring 
programs carried out in 2006-2010. A similar number of acoustic 
recorders as deployed in past years will be distributed broadly across 
the Chukchi lease area and nearshore environment. In past years, 
clusters of recorders designed to localize marine mammal calls 
originating within or nearby the clusters have been deployed on each of 
the companies' prospects: Amundsen (Statoil), Burger (Shell), and 
Klondike (CPAI). This year, recorders from the clusters are planned to 
be relocated in a broader deployment on and around Hanna Shoal.
    The recorders will be deployed in late July or mid-August and will 
be retrieved in early to mid-October, depending on

[[Page 46744]]

ice conditions. The recorders will be AMAR and AURAL model acoustic 
buoys set to record at 16 kHz sample rate. These are the same recorder 
models and same sample rates that have been used for this program from 
2006-2010. The broad area arrays are designed to capture general 
background soundscape data, industrial sounds, and marine mammal call 
data across the lease area. From previous deployments of these 
recordings, industry has been able to gain insight into large-scale 
distributions of marine mammals, identification of marine mammal 
species present, movement and migration patterns, and general abundance 
data.

Reporting Measures

(1) SSV Report
    A report on the preliminary results of the acoustic verification 
measurements, including as a minimum the measured 190-, 180-, 160-, and 
120-dBrms re 1 [mu]Pa radii of the source vessel(s) and the 
support vessels and the airgun array, will be submitted within 120 hr 
after collection and analysis of those measurements at the start of the 
field season. This report will specify the distances of the exclusion 
zones that were adopted for the marine survey activities.
(2) Field Reports
    Statoil states that throughout the survey program, the observers 
will prepare a report each day or at such other interval as the IHA or 
Statoil may require, 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.
(3) Technical Reports
    The results of Statoil's 2011 vessel-based monitoring, including 
estimates of ``take'' by harassment, will be presented in the ``90-
day'' and Final Technical reports. The Technical Reports 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) To better assess impacts to marine mammals, data analysis 
should be separated into periods when a seismic airgun array (or a 
single mitigation airgun) is operating and when it is not. Final and 
comprehensive reports to NMFS should summarize and plot:
     Data for periods when a seismic array is active and when 
it is not; and
     The respective predicted received sound conditions over 
fairly large areas (tens of km) around operations;
    (e) Sighting rates of marine mammals during periods with and 
without airgun activities (and other variables that could affect 
detectability), such as:
     Initial sighting distances versus airgun activity state;
     Closest point of approach versus airgun activity state;
     Observed behaviors and types of movements versus airgun 
activity state;
     Numbers of sightings/individuals seen versus airgun 
activity state;
     Distribution around the survey vessel versus airgun 
activity state; and
     Estimates of take by harassment;
    (f) Reported results from all hypothesis tests should include 
estimates of the associated statistical power when practicable;
    (g) Estimate and report uncertainty in all take estimates. 
Uncertainty could be expressed by the presentation of confidence 
limits, a minimum-maximum, posterior probability distribution, etc.; 
the exact approach would be selected based on the sampling method and 
data available;
    (h) The report should clearly compare authorized takes to the level 
of actual estimated takes; and
    (i) As a starting point for integrating different data sources, 
Statoil should present their 2010 and 2011 data by plotting acoustic 
detections from bottom-mounted hydrophone and visual detections from 
MMOs on a single map.
(4) Comprehensive Report
    Following the 2011 open-water season, a comprehensive report 
describing the vessel-based and acoustic 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, other 
activities that occur in the Beaufort and/or Chukchi seas, and their 
impacts on marine mammals during 2011. The report will help to 
establish long-term data sets that can assist with the evaluation of 
changes in the Chukchi and Beaufort Sea ecosystems. The report will 
attempt to provide a regional synthesis of available data on industry 
activity in offshore areas of northern Alaska that may influence marine 
mammal density, distribution, and behavior.
(5) Notification of Injured or Dead Marine Mammals
    In addition to the reporting measures proposed by Statoil, NMFS is 
requiring Statoil to notify NMFS' Office of Protected Resources and 
NMFS' Stranding Network within 48 hours of sighting an injured or dead 
marine mammal in the vicinity of marine survey operations. Statoil 
shall provide NMFS with the species or description of the animal(s), 
the condition of the animal(s) (including carcass condition if the 
animal is dead), location, time of first discovery, observed behaviors 
(if alive), and photo or video (if available).
    In the event that an injured or dead marine mammal is found by 
Statoil that is not in the vicinity of the proposed open-water marine 
survey program, Statoil will report the same information as listed 
above as soon as operationally feasible to NMFS.

Estimated Take by Incidental Harassment

    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: any act of pursuit, torment, or 
annoyance which (i) Has the potential to injure a marine mammal or 
marine mammal stock in the wild [Level A harassment]; or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [Level B harassment]. Only take by Level B behavioral 
harassment is anticipated as a result of the proposed open-water marine 
survey program. Anticipated impacts to marine mammals are associated 
with noise propagation from the survey airgun(s) used in the shallow 
hazards survey.
    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 in the Notice of Proposed IHA (76 FR 
30110; May 24, 2011). The potential effects of sound from the open-
water marine survey programs 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). As

[[Page 46745]]

discussed earlier in this document, the most common impact will likely 
be from behavioral disturbance, including avoidance of the ensonified 
area or changes in speed, direction, and/or diving profile of the 
animal. For reasons discussed previously in this document, hearing 
impairment (TTS and PTS) is 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 airgun(s) used in the 
shallow hazards survey, NMFS uses the 160 dBrms re 1 [mu]Pa 
isopleth to indicate the onset of Level B harassment. For non-impulse 
sounds, such as noise generated during the geotechnical soil 
investigation that involves drilling bore holes and running the dynamic 
positioning thruster of the vessel, NMFS uses the 120 dBrms 
re 1 [mu]Pa isopleth to indicate the onset of Level B harassment. 
Statoil provided calculations for the 160- and 120-dB isopleths 
produced by these activities and then used those isopleths to estimate 
takes by harassment. NMFS used the calculations to make the necessary 
MMPA findings. Statoil provided a full description of the methodology 
used to estimate takes by harassment in its IHA application (see 
ADDRESSES), which was also provided in the Notice of Proposed IHA (76 
FR 30110; May 24, 2011). A summary of that information is provided 
here, as it has not changed from the proposed notice.
    Statoil has requested an authorization to take 13 marine mammal 
species by Level B harassment. These 13 marine mammal species are: 
beluga whale (Delphinapterus leucas), narwhal (Monodon monoceros), 
killer whale (Orcinus orca), harbor porpoise (Phocoena phocoena), 
bowhead whale (Balaena mysticetus), gray whale (Eschrichtius robustus), 
humpback whale (Megaptera novaeangliae), minke whale (Balaenoptera 
acutorostrata), fin whale (B. physalus), bearded seal (Erignathus 
barbatus), ringed seal (Phoca hispida), spotted seal (P. largha), and 
ribbon seal (Histriophoca fasciata).

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. However, not all animals react to sounds 
at this low level, and many will not show strong reactions (and in some 
cases any reaction) until sounds are much 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 for the studies summarized the more severe 
reactions did not occur until sounds were much higher than 160 
dBrms re 1[mu]Pa.
    As described earlier in the document, a 4 x 10 in\3\ airgun cluster 
will be used to obtain geological data during the site surveys. A 
similar airgun cluster was measured by Shell in 2009 during shallow 
hazards surveys on their nearby Burger prospect (Reiser et al. 2010). 
For use in estimating potential harassment takes in this application, 
as well as for mitigation radii to be implemented by PSOs prior to SSV 
measurements, ranges to threshold levels from the 2009 measurements 
were increased by 25% as a precautionary approach (Table 1). The >= 160 
dB distance is therefore estimated to be 2.25 km (1.4 mi) from the 
source. Adding a 2.25 km (1.4 mi) perimeter to the two site survey 
areas results in an estimated area of 1,037 km\2\ being exposed to 
>=160 dB.
    Geotechnical soil investigations on the Statoil leases and leases 
jointly owned with CPAI will involve completing 3-4 boreholes at up to 
8 total prospective drilling locations for an expected maximum of 29 
boreholes. The 3-4 boreholes completed at each drilling location will 
be positioned in a square or triangle formation, roughly 100 m (328 ft) 
on each side. As described earlier, the sounds produced by soil 
investigation equipment are estimated to fall below 120 dB at a 
distance of 7.5 km (4.7 mi). Buffering 4 core sites spaced 100 m (328 
ft) apart with the 7.5 km (4.7 mi) 120 dB distance results in a total 
area of 180 km\2\. The total area exposed to sounds >= 120 dB by soil 
investigations at the 8 prospective drilling locations will therefore 
be 1,440 km\2\.
    The following subsections summarize the 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 
or non-pulsed sounds to >= 120 dB.
    Marine mammal densities near the planned activities in the Chukchi 
Sea are likely to vary by season and habitat. Therefore, densities have 
been derived for two time periods, the summer period, including July 
and August, and the fall period, including September and October. 
Animal densities encountered in the Chukchi Sea during both of these 
time periods will further depend on whether they are occurring in open 
water or near the ice margin. Vessel and equipment limitations will 
result in very little activity occurring in or near sea ice, however, 
if ice is present near the areas of activity some sounds produced by 
the activities may remain above disturbance threshold levels in ice 
margin habitats. Therefore, open water densities have been used to 
estimate potential ``take by harassment'' in 90% of the area expected 
to be ensonified above disturbance thresholds while ice margin 
densities have been used in the remaining 10% of the ensonified area.
    Detectability bias [f(0)] is associated with diminishing 
sightability with increasing lateral distance from the trackline. 
Availability bias [g(0)] refers to the fact that there is < 100% 
probability of sighting an animal that is present on the survey 
trackline. Some sources of densities used included these correction 
factors in their reported densities. In other cases the best available 
correction factors were applied to reported results when they had not 
been included in the reported analyses (e.g. Moore et al. 2000).
    Tables 2 and 3 present the expected densities of marine mammals in 
the planned survey area for both open-water and ice-margin habitat in 
the summer and fall seasons, respectively.
(1) Cetaceans
    Eight species of cetaceans are known to occur in the Chukchi Sea 
area of the Statoil project. Only four of these (bowhead, beluga, and 
gray whales, and harbor porpoise) are likely to be encountered during 
the survey activities. Three of the eight species (bowhead, fin, and 
humpback whales) are listed as endangered under the ESA. Of these, only 
the bowhead is likely to be found within the survey area.
    Beluga Whales--Summer densities of belugas in offshore waters of 
the Chukchi Sea are expected to be low, with higher densities in ice-
margin and nearshore areas. Aerial surveys have recorded few belugas in 
the offshore Chukchi Sea during the summer months (Moore et al. 2000). 
Aerial surveys of the Chukchi Sea in 2008-2009 flown by the NMML as 
part of the Chukchi Offshore Monitoring in Drilling Area project 
(COMIDA) have only reported 5 beluga sightings during > 14,000 km of 
on-transect effort, only 2 of which were

[[Page 46746]]

offshore (COMIDA 2009). If belugas are present during the summer, they 
are more likely to occur in or near the ice edge or close to shore 
during their northward migration. Effort and sightings reported by 
Clarke and Ferguson (in prep.) were used to calculate the average open-
water density estimate.
    In the fall, beluga whale densities in the Chukchi Sea are expected 
to be somewhat higher than in the summer because individuals of the 
eastern Chukchi Sea stock and the Beaufort Sea stock will be migrating 
south to their wintering grounds in the Bering Sea (Allen and Angliss 
2010). Densities derived from survey results in the northern Chukchi 
Sea in Clarke and Ferguson (in prep.) were used as the average density 
for open-water fall season estimates (see Table 3). Based on the lack 
of any beluga sightings from vessels operating in the Chukchi Sea 
during non-seismic periods and locations in September-October of 2006-
2008 (Haley et al. 2010), the relatively low densities shown in Table 3 
are consistent with what is likely to be observed from vessels during 
the planned operations.

   Table 2--Expected Densities of Cetaceans and Seals in Areas of the
 Chukchi Sea, Alaska, During the Planned Summer (July-August) Period of
                   the Shallow Hazards Survey Program
------------------------------------------------------------------------
                                      Open water          Ice margin
             Species                average density     average density
                                   (/km\2\)   (/km\2\)
------------------------------------------------------------------------
Beluga whale....................              0.0010              0.0040
Narwhal.........................              0.0000              0.0000
Killer whale....................              0.0001              0.0001
Harbor porpoise.................              0.0011              0.0011
Bowhead whale...................              0.0013              0.0013
Fin whale.......................              0.0001              0.0001
Gray whale......................              0.0258              0.0258
Humpback whale..................              0.0001              0.0001
Minke whale.....................              0.0001              0.0001
Bearded seal....................              0.0107              0.0142
Ribbon seal.....................              0.0005              0.0005
Ringed seal.....................              0.3668              0.4891
Spotted seal....................              0.0073              0.0098
------------------------------------------------------------------------


   Table 3-- Expected Densities of Cetaceans and Seals in Areas of the
 Chukchi Sea, Alaska, During the Planned Fall (September-October) Period
                  of the Shallow Hazards Survey Program
------------------------------------------------------------------------
                                      Open water          Ice margin
             Species                average density     average density
                                   (/km\2\)   (/km\2\)
------------------------------------------------------------------------
Beluga whale....................              0.0015              0.0060
Narwhal.........................              0.0000              0.0000
Killer whale....................              0.0001              0.0001
Harbor porpoise.................              0.0001              0.0001
Bowhead whale...................              0.0219              0.0438
Fin whale.......................              0.0001              0.0001
Gray whale......................              0.0080              0.0080
Humpback whale..................              0.0001              0.0001
Minke whale.....................              0.0001              0.0001
Bearded seal....................              0.0107              0.0142
Ribbon seal.....................              0.0005              0.0005
Ringed seal.....................              0.2458              0.3277
Spotted seal....................              0.0049              0.0065
------------------------------------------------------------------------

    Bowhead Whales--By July, most bowhead whales are northeast of the 
Chukchi Sea, within or migrating toward their summer feeding grounds in 
the eastern Beaufort Sea. The estimate of summer bowhead whale density 
in the Chukchi Sea was calculated by assuming there was one bowhead 
sighting during the 11,985 km of survey effort in waters 36-50 m deep 
in the Chukchi Sea during July-August reported in Clarke and Ferguson 
(in prep.), although no bowheads were actually observed during those 
surveys. Bowheads are not expected to be encountered in higher 
densities near ice in the summer (Moore et al. 2000), so the same 
density estimates are used for open-water and ice-margin habitats. 
Densities from vessel based surveys in the Chukchi Sea during non-
seismic periods and locations in July-August of 2006-2008 (Haley et al. 
2010) ranged from 0.0001-0.0007/km\2\ with a maximum 95 percent 
confidence interval (CI) of 0.0029/km\2\. This suggests the densities 
used in the calculations and shown in Table 3 are somewhat higher than 
are likely to be observed from vessels near the area of planned 
operations.
    During the fall, bowhead whales that summered in the Beaufort Sea 
and Amundsen Gulf migrate west and south to their wintering grounds in 
the Bering Sea, making it more likely that bowheads will be encountered 
in the Chukchi Sea at this time of year. Kernel densities estimated 
from GPS locations of whales suggest that bowheads do not spend much 
time (e.g., feeding or resting) in the north-central Chukchi Sea near 
the area of planned activities (Quakenbush et al. 2010). Clarke and 
Ferguson (in prep.) reported 14 sightings (15 individuals) during 
10,036 km of on transect aerial survey effort in

[[Page 46747]]

2008-2010. The mean group size from those sightings is 1.1. The same 
f(0) and g(0) values that were used for the summer estimates above were 
used for the fall estimates (Table 3). Moore et al. (2000) found that 
Bowheads were detected more often than expected in association with ice 
in the Chukchi Sea in September-October, so a density of twice the 
average open-water density was used as the average ice-margin density 
(Table 3). Densities from vessel based surveys in the Chukchi Sea 
during non-seismic periods and locations in September-October of 2006-
2008 (Haley et al. 2010) ranged from 0.0003/km\2\ to 0.0044/km\2\ with 
a maximum 95 percent CI of 0.0419 km\2\. This suggests the densities 
used in the calculations and shown in Table 3 are somewhat higher than 
are likely to be observed from vessels near the area of planned 
operations.
    Gray Whales--Gray whale densities are expected to be much higher in 
the summer months than during the fall. The average open-water summer 
density (Table 2) was calculated from effort and sightings reported by 
Clarke and Ferguson (in prep.) for water depths 36-50 m including 54 
sightings (73 individuals) during 11,985 km of on-transect effort. Gray 
whales are not commonly associated with sea ice, but may be present 
near it, so the same densities were used for ice-margin habitat as were 
derived for open-water habitat during both seasons. In the fall, gray 
whales may be dispersed more widely through the northern Chukchi Sea 
(Moore et al. 2000), but overall densities are likely to be decreasing 
as the whales begin migrating south. A density calculated from effort 
and sightings (15 sightings [19 individuals] during 10,036 km of on-
transect effort) in water 36-50 m deep during September-October 
reported by Clarke and Ferguson (in prep.) was used as the average 
estimate for the Chukchi Sea during the fall period (Table 3).
    Harbor Porpoise--Harbor Porpoise densities were estimated from 
industry data collected during 2006-2008 activities in the Chukchi Sea. 
Prior to 2006, no reliable estimates were available for the Chukchi 
Sea, and harbor porpoise presence was expected to be very low and 
limited to nearshore regions. Observers on industry vessels in 2006-
2008, however, recorded sightings throughout the Chukchi Sea during the 
summer and early fall months. Density estimates from 2006-2008 
observations during non-seismic periods and locations in July-August 
ranged from 0.0008/km\2\ to 0.0015/km\2\ with a maximum 95 percent CI 
of 0.0079/km\2\ (Haley et al. 2010). The average of those three years 
(0.0011/km\2\) was used as the average open-water density estimate 
while the high value (0.0015/km\2\) was used as the maximum estimate 
(Table 2). Harbor porpoise are not expected to be present in higher 
numbers near ice, so the open-water densities were used for ice-margin 
habitat in both seasons. Harbor porpoise densities recorded during 
industry operations in the fall months of 2006-2008 were slightly lower 
than the summer months and ranged from 0.0002/km\2\ to 0.0010/km\2\ 
with a maximum 95 percent CI of 0.0093/km\2\. The average of those 
three years (0.0001/km\2\) was again used as the average density 
estimate and the high value 0.0011/km\2\ was used as the maximum 
estimate (Table 3).
    Other Cetaceans--The remaining five cetacean species that could be 
encountered in the Chukchi Sea during Statoil's planned activities 
include the humpback whale, killer whale, minke whale, fin whale, and 
narwhal. Although there is evidence of the occasional occurrence of 
these animals in the Chukchi Sea, it is unlikely that more than a few 
individuals will be encountered during the planned activities. George 
and Suydam (1998) reported killer whales, Brueggeman et al. (1990) and 
Haley et al. (2010) reported minke whale, and COMIDA (2009) and Haley 
et al. (2010) reported fin whales. Narwhal sightings in the Chukchi Sea 
have not been reported in recent literature, but subsistence hunters 
occasionally report observations near Barrow, and Reeves et al. (2002) 
indicated a small number of extralimital sightings in the Chukchi Sea.
(2) Pinnipeds
    Four species of pinnipeds may be encountered in the Chukchi Sea: 
Ringed seal, bearded seal, spotted seal, and ribbon seal. Each of these 
species, except the spotted seal, is associated with both the ice 
margin and the nearshore area. The ice margin is considered preferred 
habitat (as compared to the nearshore areas) during most seasons.
    Ringed and Bearded Seals--Ringed seal and bearded seal summer ice-
margin densities (Table 2) were taken from Bengtson et al. (2005) who 
conducted spring surveys in the offshore pack ice zone (zone 12P) of 
the northern Chukchi Sea. However, a correction for bearded seal 
availability bias, g(0), based on haulout and diving patterns was not 
available and used in the reported densities. Densities of ringed and 
bearded seals in open water are expected to be somewhat lower in the 
summer when preferred pack ice habitat may still be present in the 
Chukchi Sea. Average and maximum open-water densities have been 
estimated as \3/4\ of the ice margin densities during both seasons for 
both species. The fall density of ringed seals in the offshore Chukchi 
Sea has been estimated as \2/3\ the summer densities because ringed 
seals begin to reoccupy nearshore fast ice areas as it forms in the 
fall. Bearded seals may also begin to leave the Chukchi Sea in the 
fall, but less is known about their movement patterns so fall densities 
were left unchanged from summer densities.
    Spotted Seal--Little information on spotted seal densities in 
offshore areas of the Chukchi Sea is available. Spotted seal densities 
in the summer were estimated by multiplying the ringed seal densities 
by 0.02. This was based on the ratio of the estimated Chukchi 
populations of the two species.
    Ribbon Seal--Two ribbon seal sightings were reported during 
industry vessel operations in the Chukchi Sea in 2006-2008 (Haley et 
al. 2010). The resulting density estimate of 0.0005/km\2\ was used as 
the average density.

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 
by pulsed airgun sounds and to >= 120 dBrms re 1 [mu]Pa by 
non-impulse sounds during geotechnical soil investigations. The 
estimates are based on a consideration of the number of marine mammals 
that might be disturbed appreciably by operations in the Chukchi Sea 
and the anticipated area exposed to those sound levels.
    The number of individuals of each species potentially exposed to 
received levels of pulsed sounds >= 160 dBrms re 1 [mu]Pa or 
to >= 120 dBrms re 1 [mu]Pa by continuous sounds within each 
season and habitat zone was estimated by multiplying:
     The anticipated area to be ensonified to the specified 
level in each season and habitat zone to which that density applies, by
     The expected species density.
    The numbers of individuals potentially exposed were then summed for 
each species across the two seasons and habitat zones. Some of the 
animals estimated to be exposed, particularly migrating bowhead whales, 
might show avoidance reactions before being exposed to pulsed airgun 
sounds >= 160 dBrms re 1 [mu]Pa. Thus, these calculations 
actually estimate the number of individuals potentially exposed to the 
specified sound levels that would occur

[[Page 46748]]

if there were no avoidance of the area ensonified to that level.
    Site survey and geotechnical soil investigations are planned to 
occur primarily in August and September, with the potential to continue 
into mid-November, if necessary and weather permitting. For the 
purposes of assigning activities to the summer (August) and fall 
(September-October) periods for which densities have been estimated 
above, NMFS has assumed that half of the operations will occur during 
the summer period and half will occur in the fall period. Additionally, 
the planned activities cannot be completed in or near significant 
amounts of sea ice, so 90% of the activity each season (and associated 
ensonified areas) has been multiplied by the open-water densities 
described above, while the remaining 10% of activity has been 
multiplied by the ice-margin densities.
    Species with an estimated average number of individuals exposed 
equal to zero are included below for completeness, but are not likely 
to be encountered.
(1) Shallow Hazards and Site Clearance Surveys
    The estimated numbers of marine mammals potentially exposed to 
airgun sounds with received levels >= 160 dBrms from site 
surveys on Statoil's leases are shown in Table 4. The average estimate 
of the number of individual bowhead whales exposed to received sound 
levels >= 160 dB is 11. The average estimate for gray whales is 
slightly greater at 18, while few belugas are expected to be exposed 
(Table 4). Few other cetaceans (such as narwhal, harbor porpoise, 
killer, humpback, fin, and minke whales) are likely to be exposed to 
airgun sounds >= 160 dB, but estimates have been included to account 
for chance encounters.
    Ringed seals are expected to be the most abundant animal in the 
Chukchi Sea during this period, and the average estimate of the number 
exposed to >= 160 dB by site survey activities is 337 (Table 4). 
Estimated exposures of other seal species are substantially below those 
for ringed seals (Table 4).

Table 4--Summary of the Number of Marine Mammals in Areas Where Maximum Received Sound Levels in the Water Would
  Be >= 160 dB in Summer (Aug) and Fall (Sep-Oct) Periods During Statoil's Planned Site Surveys in the Chukchi
  Sea, Alaska. Not All Marine Mammals Are Expected To Change Their Behavior When Exposed to These Sound Levels
----------------------------------------------------------------------------------------------------------------
                                              Number of individuals exposed to sound levels >= 160 dB
                                 -------------------------------------------------------------------------------
             Species                          Summer                           Fall
                                 ----------------------------------------------------------------      Total
                                    Open water      Ice margin      Open water      Ice margin
----------------------------------------------------------------------------------------------------------------
Beluga whale....................               0               0               1               0               2
Narwhal.........................               0               0               0               0               2
Killer whale....................               0               0               0               0               2
Harbor porpoise.................               1               0               0               0               1
Bowhead whale...................               1               0              10               0              11
Gray whale......................              12               1               4               1              18
Humpback whale..................               0               0               0               0               2
Fin whale.......................               0               0               0               0               2
Minke whale.....................               0               0               0               0               2
Bearded seal....................               5               1               5               1              12
Ribbon seal.....................               0               0               0               0               1
Ringed seal.....................             171              25             115              25             337
Spotted seal....................               3               1               2               1               7
----------------------------------------------------------------------------------------------------------------

(2) Geotechnical Soil Investigations
    The estimated numbers of marine mammals potentially exposed to 
continuous sounds with received levels >= 120 dBrms from 
geotechnical soil investigations on Statoil's leases and jointly owned 
leases are shown in Table 5. The average estimate of the number of 
individual bowhead whales exposed to received sound levels >= 120 dB is 
15. The average estimate for gray whales is slightly larger at 26 
individuals (Table 5). Few other cetaceans (such as narwhal, harbor 
porpoise, killer, humpback, fin, and minke whales) are likely to be 
exposed to soil investigation sounds >= 120 dB, but estimates have been 
included to account for chance encounters.
    The average estimate of the number of ringed seals potentially 
exposed to >= 120 dB by soil investigation activities is 467 (Table 5). 
Estimated exposures of other seal species are substantially below those 
for ringed seals (Table 5).

Table 5--Summary of the Number of Marine Mammals in Areas Where Maximum Received Sound Levels in the Water Would
       Be >= 120 dB in Summer (Aug) and Fall (Sep-Oct) Periods During Statoil's Planned Geotechnical Soil
  Investigations in the Chukchi Sea, Alaska. Not All Marine Mammals Are Expected To Change Their Behavior When
                                          Exposed to These Sound Levels
----------------------------------------------------------------------------------------------------------------
                                              Number of individuals exposed to sound levels >= 120 dB
                                 -------------------------------------------------------------------------------
             Species                          Summer                           Fall
                                 ----------------------------------------------------------------      Total
                                    Open water      Ice margin      Open water      Ice margin
----------------------------------------------------------------------------------------------------------------
Beluga whale....................               1               0               1               0               2
Narwhal.........................               0               0               0               0               3
Killer whale....................               0               0               0               0               3
Harbor porpoise.................               1               0               0               0               1

[[Page 46749]]

 
Bowhead whale...................               1               0              14               0              15
Gray whale......................              17               2               5               2              26
Humpback whale..................               0               0               0               0               3
Fin whale.......................               0               0               0               0               3
Minke whale.....................               0               0               0               0               3
Bearded seal....................               7               1               7               1              16
Ribbon seal.....................               0               0               0               0               1
Ringed seal.....................             238              35             159              35             467
Spotted seal....................               5               1               3               1              10
----------------------------------------------------------------------------------------------------------------

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''.
    Using the 160 and 120 dB criteria, the average estimates of the 
numbers of individual cetaceans exposed to received levels higher than 
these sound pressure levels represent varying proportions of the 
populations of each species in the Beaufort Sea and adjacent waters. 
For species listed as ``Endangered'' under the ESA, the estimates 
include approximately 26 bowheads. This number is approximately 0.18% 
of the Bering-Chukchi-Beaufort population of > 14,247 assuming 3.4% 
annual population growth from the 2001 estimate of > 10,545 animals 
(Zeh and Punt 2005). For other cetaceans that might occur in the 
vicinity of the shallow hazards survey in the Chukchi Sea, they also 
represent a very small proportion of their respective populations. The 
average estimates of the number of belugas, killer whales, harbor 
porpoises, gray whales, humpback whales, fin whales, and minke whales 
that might be exposed to >=160 dB and 120 dB re 1 [mu]Pa are 4, 5, 2, 
44, 5, 5, and 5. These numbers represent 0.11%, 1.59%, 0.004%, 0.25%, 
0.53%, 0.09%, and 0.50% of these species of their respective 
populations in the proposed action area. No population estimates of 
narwhal are available in U.S. waters due to its extralimital 
distribution here. The world population of narwhal is estimated at 
75,000 (Laidre et al. 2008), and most of them are concentrated in the 
fjords and inlets of Northern Canada and western Greenland. The 
estimated take of 5 narwhals represents approximately 0.01% of its 
population.
    Seals--A few seal species are likely to be encountered in the study 
area, but ringed seal is by far the most abundant in this area. The 
average estimates of the numbers of individuals exposed to sounds at 
received levels = 160 and 120 dBrms re 1 [mu]Pa 
during the proposed shallow hazards survey and geotechnical soil 
investigation are as follows: Ringed seals (803), bearded seals (28), 
spotted seals (17), and ribbon seals (2). These numbers represent 
0.35%, 0.01%, 0.03%, and 0.002% of Alaska stocks of ringed, bearded, 
spotted, and ribbon seals, respectively.

Negligible Impact and Small Numbers Analysis and Determination

    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as ``* * * 
an impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.'' In making a negligible impact determination, 
NMFS 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.
    No injuries or mortalities are anticipated to occur as a result of 
Statoil's proposed 2011 open water marine shallow hazards surveys in 
the Chukchi Seas, and none are authorized. In addition, these surveys 
would use a small 40 in\3\ airgun array and several mid- to high-
frequency active acoustic sources. The acoustic power output is much 
lower than full scale airgun arrays used in a 2D or 3D seismic survey 
and thus generates much lower source levels. The modeled isopleths at 
160 dB is expected to be less than 2.25 km (1.4 mi) from the airgun 
source (see discussion earlier). Additionally, animals in the area are 
not expected to incur hearing impairment (i.e., TTS or PTS) or non-
auditory physiological effects. Takes will be limited to Level B 
behavioral harassment. Although it is possible that some individuals of 
marine mammals may be exposed to sounds from shallow hazards survey 
activities more than once, the expanse of these multi-exposures are 
expected to be less extensive since both the animals and the survey 
vessels will be moving constantly in and out of the survey areas.
    Most of the bowhead whales encountered during the summer will 
likely show overt disturbance (avoidance) only if they receive airgun 
sounds with levels >= 160 dB re 1 [mu]Pa. Odontocete reactions to 
seismic energy pulses are usually assumed to be limited to shorter 
distances from the airgun(s) than are those of mysticetes, probably in 
part because odontocete low-frequency hearing is assumed to be less 
sensitive than that of mysticetes. However, at least 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). Belugas 
will likely occur in small numbers in the Chukchi Sea during the survey 
period, and few will likely be affected by the survey activity. 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.

[[Page 46750]]

    For animals exposed to machinery noise from geotechnical soil 
investigations, NMFS considers that at received levels >= 120 dB re 1 
[mu]Pa, the animals could respond behaviorally in a manner that NMFS 
considers Level B harassment due to the non-pulse nature of the noise 
involved in this activity. During soil investigation operations, the 
most intensive noise source is from the DP system that automatically 
controls and coordinates vessel movements using bow and/or stern 
thrusters. Measurements of a similar vessel in DP mode in the Chukchi 
Sea in 2010 provided an estimated source level at about 176 dB re 1 
[mu]Pa, which is below what NMFS uses to assess Level A harassment of 
received levels at 180 dB for cetaceans and 190 dB for pinnipeds. 
Therefore, no hearing impairment is anticipated. In addition, the 
duration of the entire geotechnical soil investigation is approximately 
14 days, and DP will only be running sporadically when needed to 
position the vessel. In addition, the soil investigation operations are 
expected to be stationary, with limited area to be ensonified. 
Therefore, the impacts to marine mammals in the vicinity of the soil 
investigation operations are expected to be in short duration and 
localized.
    Taking into account the mitigation measures that are required to be 
implemented, 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''. Furthermore, the estimated numbers of 
animals potentially exposed to sound levels sufficient to cause 
appreciable disturbance are very low percentages of the population 
sizes in the Bering-Chukchi-Beaufort seas, as described above.
    The many reported cases of apparent tolerance by cetaceans of 
seismic exploration, vessel traffic, and some other human activities 
show that co-existence is possible. Mitigation measures such as 
controlled vessel speed, dedicated PSOs, 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 are expected to be short-term, 
with no lasting biological consequence.
    Some individual pinnipeds may be exposed to sound from the 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. 
Therefore, NMFS has determined that the exposure of pinnipeds to sounds 
produced by the shallow hazards surveys and soil investigation in the 
Chukchi Sea is not expected to result in more than Level B harassment 
and is anticipated to have no more than a negligible impact on the 
animals.
    Of the thirteen marine mammal species likely to occur in the marine 
survey area, only the bowhead, fin, and humpback whales are listed as 
endangered under the ESA. These species are also designated as 
``depleted'' under the MMPA. Despite these designations, the Bering-
Chukchi-Beaufort stock of bowheads has been increasing at a rate of 3.4 
percent annually for nearly a decade (Allen and Angliss 2010). 
Additionally, during the 2001 census, 121 calves were counted, which 
was the highest yet recorded. The calf count provides corroborating 
evidence for a healthy and increasing population (Allen and Angliss 
2010). The occurrence of fin and humpback whales in the marine survey 
areas is considered very rare. There is no critical habitat designated 
in the U.S. Arctic for the bowhead, fin, and humpback whale. On 
December 10, 2010, NMFS published a notification of proposed threatened 
status for subspecies of the ringed seal (75 FR 77476) and a 
notification of proposed threatened and not warranted status for 
subspecies and distinct population segments of the bearded seal (75 FR 
77496) in the Federal Register. Neither species is considered depleted 
under the MMPA. The listing for these species is not anticipated to be 
completed prior to the end of this proposed seismic survey. None of the 
other species that may occur in the project area are listed as 
threatened or endangered under the ESA or designated as depleted under 
the MMPA.
    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 vast size of the Arctic Ocean 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.
    The estimated authorized takes represent 0.11% of the Eastern 
Chukchi Sea population of approximately 3,710 beluga whales (Allen and 
Angliss 2010), 1.59% of Aleutian Island and Bering Sea stock of 
approximately 314 killer whales, 0.004% of Bering Sea stock of 
approximately 48,215 harbor porpoises, 0.25% of the Eastern North 
Pacific stock of approximately 17,752 gray whales, 0.18% of the Bering-
Chukchi-Beaufort population of 14,247 bowhead whales assuming 3.4 
percent annual population growth from the 2001 estimate of 10,545 
animals (Zeh and Punt, 2005), 0.53% of the Western North Pacific stock 
of approximately 938 humpback whales, 0.09% of the North Pacific stock 
of approximately 5,700 fin whales, and 0.50% of the Alaska stock of 
approximately 1,003 minke whales. The take estimates presented for 
bearded, ringed, spotted, and ribbon seals represent 0.01, 0.35, 0.03, 
and 0.002 percent of U.S. Arctic stocks of each species, respectively. 
These 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. In addition, the mitigation and monitoring measures 
(described previously in this document) required in the IHA are 
expected to reduce even further any potential disturbance to marine 
mammals.
    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 Statoil's 2011 open-water shallow hazards 
survey in the Chukchi Sea may result in the incidental take of small 
numbers of marine mammals, by Level B harassment only, and that the 
total taking from the marine surveys will have a negligible impact on 
the affected species or stocks.
    Impact on Availability of Affected Species or Stock for Taking for 
Subsistence Uses

Relevant Subsistence Uses

    The disturbance and potential displacement of marine mammals by 
sounds from the proposed marine surveys are the principal concerns 
related to subsistence use of the area. Subsistence remains the basis 
for Alaska Native culture and community. Subsistence hunting and 
fishing continue to be prominent in the household economies and social 
welfare of some Alaskan residents, particularly among those living in 
small, rural

[[Page 46751]]

villages (Wolfe and Walker 1987). In rural Alaska, subsistence 
activities are often central to many aspects of human existence, 
including patterns of family life, artistic expression, and community 
religious and celebratory activities. Additionally, the animals taken 
for subsistence provide a significant portion of the food that will 
last the community throughout the year. The main species that are 
hunted include bowhead and beluga whales, ringed, spotted, and bearded 
seals, walruses, and polar bears. (Both the walrus and the polar bear 
are under the USFWS' jurisdiction.) The importance of each of these 
species varies among the communities and is largely based on 
availability.
    Bowhead whales, belugas, and walruses are the marine mammal species 
primarily harvested during the time of Statoil's shallow hazards 
survey. There is little or no bowhead hunting by the community of Point 
Lay, so beluga and walrus hunting are of more importance there. Members 
of the Wainwright community hunt bowhead whales in the spring, although 
bowhead whale hunting conditions there are often more difficult than 
elsewhere, and they do not hunt bowheads during seasons when Statoil's 
survey operation would occur. Depending on the level of success during 
the spring bowhead hunt, Wainwright residents may be very dependent on 
the presence of belugas in a nearby lagoon system during July and 
August. Barrow residents focus hunting efforts on bowhead whales during 
the spring and generally do not hunt beluga then. However, Barrow 
residents also hunt in the fall, when Statoil expects to be conducting 
shallow hazards surveys (though not near Barrow).
(1) Bowhead Whales
    Bowhead whale hunting is a key activity in the subsistence 
economies of northwest Arctic communities. An overall quota system for 
the hunting of bowhead whales was established by the International 
Whaling Commission (IWC) in 1977. The quota is now regulated through an 
agreement between NMFS and the AEWC. The AEWC allots the number of 
bowhead whales that each whaling community may harvest annually (USDI/
BLM 2005). The annual take of bowhead whales has varied due to (a) 
Changes in the allowable quota level and (b) year-to-year variability 
in ice and weather conditions, which strongly influence the success of 
the hunt.
    Bowhead whales migrate around northern Alaska twice each year, 
during the spring and autumn, and are hunted in both seasons. Bowhead 
whales are hunted from Barrow during the spring, and the fall migration 
and animals are not successfully harvested every year. The spring hunt 
along Chukchi villages and at Barrow occurs after leads open due to the 
deterioration of pack ice; the spring hunt typically occurs from early 
April until the first week of June. The fall migration of bowhead 
whales that summer in the eastern Beaufort Sea typically begins in late 
August or September. Fall migration into Alaskan waters is primarily 
during September and October.
    In the fall, subsistence hunters use aluminum or fiberglass boats 
with outboards. Hunters prefer to take bowheads close to shore to avoid 
a long tow during which the meat can spoil, but Braund and Moorehead 
(1995) report that crews may (rarely) pursue whales as far as 50 mi (80 
km). The autumn bowhead hunt usually begins in Barrow in mid-September, 
and mainly occurs in the waters east and northeast of Point Barrow.
    The scheduling of this shallow hazard survey has been discussed 
with representatives of those concerned with the subsistence bowhead 
hunt, most notably the AEWC, the Barrow Whaling Captains' Association, 
and the North Slope Borough (NSB) Department of Wildlife Management.
    The planned mobilization and start date for shallow hazards surveys 
in the Chukchi Sea (~25 July and ~1 August, respectively) is well after 
the end of the spring bowhead migration and hunt at Wainwright and 
Barrow. Shallow hazards survey and soil investigation operations will 
be conducted far offshore from Barrow and Wainwright and are not 
expected to conflict with subsistence hunting activities. Specific 
concerns of the Barrow whaling captains are addressed as part of the 
Plan of Cooperation discussed below.
(2) Beluga Whales
    Beluga whales are available to subsistence hunters along the coast 
of Alaska in the spring when pack-ice conditions deteriorate and leads 
open up. Belugas may remain in coastal areas or lagoons through June 
and sometimes into July and August. The community of Point Lay is 
heavily dependent on the hunting of belugas in Kasegaluk Lagoon for 
subsistence meat. From 1983-1992 the average annual harvest was ~40 
whales (Fuller and George 1997). In Wainwright and Barrow, hunters 
usually wait until after the spring bowhead whale hunt is finished 
before turning their attention to hunting belugas. The average annual 
harvest of beluga whales taken by Barrow for 1962-1982 was five (MMS 
1996). The Alaska Beluga Whale Committee recorded that 23 beluga whales 
had been harvested by Barrow hunters from 1987 to 2002, ranging from 0 
in 1987, 1988 and 1995 to the high of 8 in 1997 (Fuller and George 
1997; Alaska Beluga Whale Committee 2002 in USDI/BLM 2005). The seismic 
survey activities take place well offshore, far away from areas that 
are used for beluga hunting by the Chukchi Sea communities. 
Additionally, Statoil's mobilization date is after the usual completion 
date of the spring beluga hunt in Kasegaluk Lagoon (i.e., July 15 for 
end date of the hunt).
(3) Ringed Seals
    Ringed seals are hunted mainly from October through June. Hunting 
for these smaller mammals is concentrated during winter because bowhead 
whales, bearded seals, and caribou are available during other seasons. 
In winter, leads and cracks in the ice off points of land and along the 
barrier islands are used for hunting ringed seals. The average annual 
ringed seal harvest was 49 seals in Point Lay, 86 in Wainwright, and 
394 in Barrow (Braund et al. 1993; USDI/BLM 2003; 2005). Although 
ringed seals are available year-round, the planned activities will not 
occur during the primary period when these seals are typically 
harvested. Also, the activities will be largely in offshore waters 
where the activities will not influence ringed seals in the nearshore 
areas where they are hunted.
(4) Spotted Seals
    The spotted seal subsistence hunt peaks in July and August along 
the shore where the seals haul out but usually involves relatively few 
animals. Spotted seals typically migrate south by October to overwinter 
in the Bering Sea. During the fall migration, spotted seals are hunted 
by the Wainwright and Point Lay communities as the seals move south 
along the coast (USDI/BLM 2003). Spotted seals are also occasionally 
hunted in the area off Point Barrow and along the barrier islands of 
Elson Lagoon to the east (USDI/BLM 2005). The planned activities will 
remain offshore of the coastal harvest area of these seals and should 
not conflict with harvest activities.
(5) Bearded Seals
    Bearded seals, although generally not favored for their meat, are 
important to subsistence activities in Barrow and Wainwright, because 
of their skins. Six to nine bearded seal hides are used by whalers to 
cover each of the skin-covered boats traditionally used for spring 
whaling. Because of their valuable hides and large size, bearded seals 
are specifically sought. Bearded

[[Page 46752]]

seals are harvested during the spring and summer months in the Chukchi 
Sea (USDI/BLM 2003; 2005). The animals inhabit the environment around 
the ice floes in the drifting nearshore ice pack, so hunting usually 
occurs from boats in the drift ice. Most bearded seals are harvested in 
coastal areas inshore of the survey, so no conflicts with the harvest 
of bearded seals are expected.
    In the event that both marine mammals and hunters are near the 
areas of planned operations, the project potentially could impact the 
availability of marine mammals for harvest in a small area immediately 
around the vessel, in the case of pinnipeds, and possibly in a large 
area in the case of migrating bowheads. However, the majority of marine 
mammals are taken by hunters within ~21 mi (~33 km) from shore, and the 
survey activities will occur far offshore, well outside the hunting 
areas. Considering the timing and location of the shallow hazards 
survey activities, as described earlier in the document, the project is 
not expected to have any significant impacts to the availability of 
marine mammals for subsistence harvest. Specific concerns of the 
respective communities are addressed as part of the Plan of Cooperation 
between Statoil and the AEWC.

Potential Impacts to Subsistence Uses

    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.

    Noise and general activity during Statoil's open-water shallow 
hazards survey have the potential to impact marine mammals hunted by 
Native Alaskans. In the case of cetaceans, the most common reaction to 
anthropogenic sounds (as noted previously in this document) is 
avoidance of the ensonified area. In the case of bowhead whales, this 
often means that the animals divert from their normal migratory path by 
several kilometers. Additionally, general vessel presence in the 
vicinity of traditional hunting areas could negatively impact a hunt.
    In the case of subsistence hunts for bowhead whales in the Chukchi 
Sea, there could be an adverse impact on the hunt if the whales were 
deflected seaward (further from shore) in traditional hunting areas. 
The impact would be that whaling crews would have to travel greater 
distances to intercept westward migrating whales, thereby creating a 
safety hazard for whaling crews and/or limiting chances of successfully 
striking and landing bowheads.
    In addition, Native knowledge indicates that bowhead whales become 
increasingly ``skittish'' in the presence of seismic noise. Whales are 
more wary around the hunters and tend to expose a much smaller portion 
of their back when surfacing (which makes harvesting more difficult). 
Additionally, natives report that bowheads exhibit angry behaviors in 
the presence of seismic, such as tail-slapping, which translate to 
danger for nearby subsistence harvesters.

Plan of Cooperation (POC or Plan)

    Regulations at 50 CFR 216.104(a)(12) require IHA applicants for 
activities that take place in Arctic waters to provide a POC or 
information that identifies what measures have been taken and/or will 
be taken to minimize adverse effects on the availability of marine 
mammals for subsistence purposes.
    Statoil states that it intends to maintain an open and transparent 
process with all stakeholders throughout the life-cycle of activities 
in the Chukchi Sea. Statoil began the stakeholder engagement process in 
2009 with meeting Chukchi Sea community leaders at the tribal, city, 
and corporate level. Statoil will continue to engage with leaders, 
community members, and subsistence groups, as well as local, state, and 
federal regulatory agencies throughout the exploration and development 
process.
    As part of stakeholder engagement, Statoil developed a POC for the 
2011 activities. The POC summarizes the actions Statoil will take to 
identify important subsistence activities, inform subsistence users of 
the proposed survey activities, and obtain feedback from subsistence 
users regarding how to promote cooperation between subsistence 
activities and the Statoil program.
    During the early phase of the POC process for the project, Statoil 
met with the North Slope Borough Department of Wildlife Management (Dec 
2010) and the AEWC (mini-convention in Barrow, Feb 2011). Statoil also 
arranged to visit and hold public meetings in the affected Chukchi Sea 
villages, including Pt. Hope, Pt. Lay, Wainwright, and Barrow during 
the week of March 21, 2011.
    Based upon these meetings, a final POC that documents all 
consultations with community leaders, subsistence user groups, 
individual subsistence users, and community members was submitted to 
NMFS on July 14, 2011. Subsistence mitigation measures that Statoil 
will implement during the shallow hazards survey program were described 
in the Mitigation Measures section earlier in this document.

Unmitigable Adverse Impact Analysis and Determination

    NMFS has determined that Statoil's proposed 2011 open water shallow 
hazards survey in the Chukchi Sea will not have an unmitigable adverse 
impact on the availability of species or stocks for taking for 
subsistence uses. This determination is supported by information 
contained in this document and Statoil's POC. Statoil has adopted a 
spatial and temporal strategy for its Chukchi Sea operations that 
should minimize impacts to subsistence hunters. Statoil will enter the 
Chukchi Sea far offshore, so as to not interfere with July hunts in the 
Chukchi Sea villages, if they are still ongoing. After the close of the 
July beluga whale hunts in the Chukchi Sea villages, very little 
whaling occurs in Wainwright, Point Hope, and Point Lay. Although the 
fall bowhead whale hunt in Barrow will occur while Statoil is still 
operating (mid- to late September to October), Barrow is approximately 
150 mi (241 km) east of the eastern boundary of the shallow hazards 
survey site. Because the whales are migrating westward from the 
Canadian Beaufort Sea, they will reach Barrow before entering the area 
of Statoil's activities. Based on these factors, Statoil's Chukchi Sea 
shallow hazards survey is not expected to interfere with the fall 
bowhead harvest in Barrow. In recent years, bowhead whales have 
occasionally been taken in the fall by coastal villages along the 
Chukchi coast, but the total number of these animals has been small.
    Adverse impacts are not anticipated on sealing activities since the 
majority of hunts for seals occur in the winter and spring, when 
Statoil will not be operating. Additionally, most sealing activities 
occur much closer to shore than Statoil's shallow hazards survey area.
    Based on the measures described in Statoil's POC, mitigation and 
monitoring measures (described earlier in this document), and the 
project design itself, NMFS has determined that there will not be an 
unmitigable adverse impact on subsistence uses of marine mammals from 
Statoil's open-water

[[Page 46753]]

shallow hazards survey in the Chukchi Sea.

Endangered Species Act (ESA)

    There are three marine mammal species listed as endangered under 
the ESA with confirmed or possible occurrence in the project area: The 
bowhead, humpback, and fin whales. NMFS' Permits, Conservation and 
Education Division consulted with NMFS' Protected Resources Division 
under section 7 of the ESA on the issuance of an IHA to Statoil under 
section 101(a)(5)(D) of the MMPA for this activity. A Biological 
Opinion was issued on July 22, 2011, which concludes that issuance of 
an IHA is not likely to jeopardize the continued existence of the fin, 
humpback, or bowhead whale. NMFS has issued an Incidental Take 
Statement under this Biological Opinion which contains reasonable and 
prudent measures with implementing terms and conditions to minimize the 
effects of take of listed species.

National Environmental Policy Act (NEPA)

    In 2010, NMFS prepared an EA and issued FONSIs for open-water 
seismic and marine surveys in the Beaufort and Chukchi seas by Shell 
and Statoil. A review of Statoil's proposed 2011 open-water shallow 
hazards surveys indicates that the planned action is essentially the 
same as the marine survey conducted by Shell in 2010, but on a smaller 
scale. In addition, the review indicated that there is no significant 
change in the environmental baselines from those analyzed in 2010. 
Therefore, NMFS has prepared a Supplemental EA which incorporates by 
reference the 2010 EA and other related documents and updates the 
activity to reflect the lower impacts compared to the previous season. 
A FONSI was issued for this action on July 21, 2011. Therefore, 
preparation of an EIS is not necessary.

Authorization

    As a result of these determinations, NMFS has issued an IHA to 
Statoil to take marine mammals incidental to its 2011 open-water 
shallow hazards and geotechnical surveys in the Chukchi Sea, Alaska, 
provided the previously mentioned mitigation, monitoring, and reporting 
requirements are incorporated.

    Dated: July 28, 2011.
Helen Golde,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2011-19663 Filed 8-2-11; 8:45 am]
BILLING CODE 3510-22-P