[Federal Register Volume 77, Number 90 (Wednesday, May 9, 2012)]
[Notices]
[Pages 27189-27202]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-11207]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XA961


Takes of Marine Mammals Incidental to Specified Activities; Low-
Energy Marine Geophysical Survey in the South-Eastern Pacific Ocean, 
May, 2012

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) 
regulation, notification is hereby given that NMFS has issued an 
Incidental Harassment Authorization (IHA) to the Scripps Institution of 
Oceanography (SIO) to take marine mammals, by Level B harassment, 
incidental to conducting a low-energy marine geophysical (i.e., 
seismic) survey in the south-eastern Pacific Ocean, May, 2012.

DATES: Effective May 4, 2012 through June 29, 2012.

ADDRESSES: A copy of the final IHA and application are available by 
writing to Tammy Adams, Acting Chief, Permits and Conservation 
Division, Office of Protected Resources, National Marine Fisheries 
Service, 1315 East-West Highway, Silver Spring, MD 20910 or by 
telephoning the contacts listed here.
    A copy of the IHA application containing a list of the references 
used in this document may be obtained by writing to the above address, 
telephoning the contact listed here (see FOR FURTHER INFORMATION 
CONTACT) or visiting the Internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.

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

SUPPLEMENTARY INFORMATION:

Background

    Section 101(a)(5)(D) of the MMPA (16 U.S.C. 1371 (a)(5)(D)) directs 
the Secretary of Commerce (Secretary) to authorize, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals of a species or population stock, by United States citizens who 
engage in a specified activity (other than commercial fishing) within a 
specified geographical region if certain findings are made and, if the 
taking is limited to harassment, a notice of a proposed authorization 
is provided to the public for review.
    Authorization for the incidental taking of small numbers of marine 
mammals shall be granted if NMFS finds that the taking will have a 
negligible impact on the species or stock(s), and will not have an 
unmitigable adverse impact on the availability of the species or 
stock(s) for subsistence uses (where relevant). The authorization must 
set forth the permissible methods of taking, other means of effecting 
the least practicable impact on the species or stock and its habitat, 
and requirements pertaining to the mitigation, monitoring and reporting 
of such takings. NMFS has defined ``negligible impact'' in 50 CFR 
216.103 as ``* * * an impact resulting from the specified activity that 
cannot be reasonably expected to, and is not reasonably likely to, 
adversely affect the species or stock through effects on annual rates 
of recruitment or survival.''
    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which citizens of the United States can apply for an authorization 
to incidentally take small numbers of marine mammals by harassment. 
Section 101(a)(5)(D) of the MMPA establishes a 45-day time limit for 
NMFS's review of an application followed by a 30-day public notice and 
comment period on any proposed authorizations for the incidental 
harassment of small numbers of marine mammals. Within 45 days of the 
close of the public comment period, NMFS must either issue or deny the 
authorization.
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild [Level A harassment]; or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [Level B harassment].
    The National Science Foundation (NSF) has prepared a ``National 
Environmental Policy Act Analysis Pursuant to Executive Order 12114 of 
a Marine Geophysical Survey by the R/V Melville in the South-Eastern 
Pacific Ocean May 2012.'' The analysis incorporates an ``Final 
Environmental Analysis of a Marine Geophysical Survey by the R/V 
Melville in the South-Eastern Pacific Ocean off Chile, May 2012,'' 
prepared by LGL Ltd., Environmental Research Associates (LGL), on 
behalf of NSF and SIO, which is also available at the same internet 
address. To meet NMFS's NEPA requirements for the issuance of an IHA to 
SIO, NMFS prepared an ``Environmental Assessment on the Issuance of an 
Incidental Harassment Authorization to the Scripps Institution of 
Oceanography to Take Marine Mammals by Harassment Incidental to a 
Marine Geophysical Survey in the South-Eastern Pacific Ocean, May, 
2012.'' NMFS also issued a Biological Opinion (BiOp) under section 7 of 
the Endangered Species Act (ESA) to evaluate the effects of the survey 
and IHA on marine species listed as threatened or endangered. The NMFS 
BiOp will be available online at: http:// www.nmfs.noaa.gov/pr/consultations/opinions.htm. Documents cited in this notice may be 
viewed, by appointment, during regular business hours, at the 
aforementioned address.

Summary of Request

    NMFS received an application on December 23, 2011, from SIO for the 
taking by harassment, of marine mammals, incidental to conducting a 
low-energy marine seismic survey in the

[[Page 27190]]

south-eastern Pacific Ocean. SIO, a part of the University of 
California San Diego, with research funding from the NSF, plans to 
conduct a low-energy seismic survey in the South-Eastern Pacific Ocean 
off the coast of Chile during May, 2012, for approximately five to 11 
days. The survey will use a pair of Generator Injector (GI) airguns 
each with a discharge volume of 45 or 105 cubic inches (in\3\) (maximum 
total volume of 210 in\3\) . SIO plans to conduct the survey from 
approximately May 4 to 18, 2012. The seismic survey will be conducted 
in the Exclusive Economic Zone (EEZ) of Chile. On behalf of SIO, the 
U.S. State Department will seek authorization from Chile for clearance 
to work in its EEZ. On March 13, 2012, NMFS published a notice in the 
Federal Register (77 FR 14744) making preliminary determinations and 
proposing to issue an IHA. The notice initiated a 30 day public comment 
period.
    SIO plans to use one source vessel, the R/V Melville (Melville) and 
a seismic airgun array to collect seismic reflection and refraction 
profiles to monitor the post-seismic response of the outer acretionary 
prism, the area where sediments are accreted onto the non-subducting 
tectonic plate at the convergent plate boundary off of the coast of 
Chile. In addition to the operations of the seismic airgun array, SIO 
intends to operate a multibeam echosounder (MBES) and a sub-bottom 
profiler (SBP) continuously throughout the survey.
    Acoustic stimuli (i.e., increased underwater sound) generated 
during the operation of the seismic airgun array may have the potential 
to cause a short-term behavioral disturbance for marine mammals in the 
survey area. This is the principal means of marine mammal taking 
associated with these activities and SIO has requested an authorization 
to take 20 species of marine mammals by Level B harassment. Take is not 
expected to result from the use of the MBES or SBP, for reasons 
discussed in this notice; nor is take expected to result from collision 
with the vessel because it is a single vessel moving at a relatively 
slow speed during seismic acquisition within the survey, for a 
relatively short period of time (approximately five to 11 days). It is 
likely that any marine mammal would be able to avoid the vessel.

Description of the Specified Activity

    SIO's planned seismic survey in the south-eastern Pacific Ocean 
will take place for approximately 5 to 11 days in May, 2012 (see Figure 
1 of the IHA application). The seismic survey will take place in water 
depths ranging from approximately 1,000 to 5,300 meters (m) (3,280.8 to 
17,388.5 feet [ft]) and the program will consist of approximately 1,145 
kilometers (km) (618.3 nautical miles [nmi]) of seismic survey 
tracklines (see Figure 1 of the IHA application). The survey will take 
place in the area approximately 34[deg] to 36[deg] South, 72[deg] to 
74[deg] West, off the coast of Chile. The project is scheduled to occur 
from approximately May 4 to 18, 2012. Some minor deviation from these 
dates is possible, depending on logistics and weather.
    The survey will involve one source vessel, the Melville. For the 
seismic component of the research program, the Melville will deploy an 
array of two low-energy Sercel Generator Injector (GI) airguns as an 
energy source (each with a discharge volume of 45 or 105 in\3\, maximum 
total volume 210 in\3\) at a tow depth of 2 m (6.6 ft). The acoustic 
receiving system will consist of a 200 to 800 m (656.2 to 2,624.7 ft) 
hydrophone streamer with up to 48 channels with 12.5 m (41 ft) channel 
spacing, and broadband Ocean Bottom Seismometers (OBSs). The energy to 
the airguns is compressed air supplied by compressors on board the 
source vessel. As the airgun is towed along the survey lines, the 
hydrophone streamer will receive the returning acoustic signals and 
transfer the data to the on-board processing system. The OBSs acquire 
the signal, process the data, and log it internally until the 
instrument is retrieved and the data is recovered.
    SIO plans to use conventional low-energy seismic methodology to 
monitor the post-seismic response of the outer accretionary prism, the 
area where sediments are accreted onto the non-subducting tectonic 
plate at the convergent plate boundary. To provide constraints on the 
fault structure and seismic stratigraphy in the accretionary wedge, 
high resolution seismic data will be acquired using two GI airguns shot 
simultaneously. Simultaneous shots from both airguns will provide 
penetration to basement in the trench and clearly define fault 
structures and folds in the slop basin sediments that overlie the 
accretionary complex. The primary tracklines, approximately 569 km 
(307.2 nmi), identified in Figure 1 of the IHA application, will be 
surveyed first. Depending on the weather, quality and at sea 
conditions, efforts will be made to survey the secondary tracklines, 
approximately 576 km (311 nmi), identified in Figure 1 of the IHA 
application. During the survey OBSs will be deployed and survey 
profiles will be taken along the tracklines that extend from the trench 
across the accretionary complex to the region of greatest slip. These 
data will be processed onboard the vessel and will be used to optimize 
the location of remaining profiles to be collected within the survey 
site area. In addition to the operations of the airgun array, a MBES 
and SBP will also be operated from the Melville continuously throughout 
the cruise. There will be additional seismic operations associated with 
equipment testing, start-up, and possible line changes or repeat 
coverage of any areas where initial data quality is sub-standard. In 
SIO's calculations, 25% has been added for those contingency 
operations.
    All planned geophysical data acquisition activities will be 
conducted by technicians provided by SIO, with on-board assistance by 
the scientists who have planned the study. The Principal Investigator 
(PI) is Dr. Anne Trehu of Oregon State University. The vessel will be 
self-contained, and the crew will live aboard the vessel for the entire 
cruise.

Description of the Dates, Duration, and Specified Geographic Region

    The Melville is expected to depart and return to Bahia de 
Valparaiso, Chile. The cruise is scheduled to occur for approximately 5 
to 11 days from May 4 to 18, 2012. Of the approximately 15 day cruise, 
approximately five days will be spent collecting seismic data along the 
primary tracklines, with potential for an additional six days of 
seismic data acquisition along the secondary tracklines, barring 
weather or instrument related issues. Remaining cruise time will be 
spent transiting to and from port. Some minor deviation from this 
schedule is possible, depending on logistics and weather. The survey 
will occur in the area approximately 34[deg] to 35[deg] South, 
approximately 72[deg] to 74[deg] West (see Figure 1 of the IHA 
application). Water depths in the survey area generally range from 
approximately 1,000 to 5,300 m (3,280.8 to 17,388.5 ft). The seismic 
survey will be conducted in the EEZ of Chile, approximately 50 km (27 
nmi) off the coast of Chile.
    NMFS outlined the purpose of the program in a previous notice for 
the proposed IHA (77 FR 14744, March 13, 2012). The activities to be 
conducted have not changed between the proposed IHA notice and this 
final notice announcing the issuance of the IHA. For a more detailed 
description of the authorized action, including vessel and acoustic 
source specifications, the reader should refer to the proposed IHA 
notice (77 FR 14744, March 13, 2012), the IHA application, EA, and 
associated

[[Page 27191]]

documents referenced above this section.

Comments and Responses

    A notice of proposed IHA for the SIO seismic survey was published 
in the Federal Register on March 13, 2012 (77 FR 14744). During the 30 
day public comment period, NMFS received comments from the Marine 
Mammal Commission (Commission). The Commission's comments are online 
at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm. Following are 
their substantive comments and NMFS's response:
    Comment 1: The Commission recommends that NMFS require SIO to re-
estimate exclusion zones (EZ) and buffer zones for the two airgun array 
and associated number of marine mammal takes using operational and 
site-specific environmental parameters--if the EZs and buffer zones and 
number of takes are not re-estimated; and require SIO to provide a 
detailed justification for basing the EZs and buffer zones for the 
proposed survey in the south-eastern Pacific Ocean on modeling that 
relies on measurements from the Gulf of Mexico (GOM). The Commission 
would like an opportunity to evaluate the detailed justification prior 
to issuance of the authorization.
    Response: With respect to the Commission's first point, based upon 
the best available information and NMFS' analysis of the likely effects 
of the specified activity on marine mammals and their habitat, NMFS is 
satisfied that the data supplied by SIO are sufficient for NMFS to 
conduct its analysis and support the determinations under the MMPA, 
Endangered Species Act of 1973 (ESA; 16 U.S.C. 1531 et seq.), and the 
National Environmental Policy Act (NEPA). The identified zones are 
appropriate for the survey and additional field measurements are not 
necessary at this time. Thus, for this survey, NMFS will not require 
SIO to re-estimate the proposed exclusion zones (EZs) and buffer zones 
and associated number of marine mammal takes using operational and 
site-specific environmental parameters.
    With respect to the Commission's second point, SIO has modeled the 
EZ and buffer zones in the action area based on L-DEO's 2003 (Tolstoy 
et al., 2004) and 2007-2008 (Tolstoy et al., 2009) peer-reviewed, 
calibration studies in the northern Gulf of Mexico. Received levels 
have been modeled by L-DEO for a number of airgun configurations, 
including two 105 in\3\ GI airguns, in relation to distance and 
direction from the airguns (see Figure 2a and 2b of the IHA 
application). NSF's environmental analysis (see Appendix A) includes 
detailed information on the study, their modeling process, and a 
comparison of SIO's modeled results with results of the 2007 to 2008 
Marcus G. Langseth calibration experiment in shallow, intermediate, and 
deep water. The conclusions in Appendix A show that SIO's model 
represents the actual produced sound levels, particularly within the 
first few kms, where the predicted zone (i.e., EZ) lie. At greater 
distances, local oceanographic variations begin to take effect, and the 
model tends to over predict.
    Because the modeling matches the observed measurement data, the 
authors concluded that those using the models to predict zones can 
continue to do so, including predicting EZs and buffer zones around the 
vessel for various tow depths. At present, L-DEO's model does not 
account for site-specific environmental conditions and the calibration 
study analysis of the model predicted that using site-specific 
information may actually estimate less conservative EZs at greater 
distances.
    While it is difficult to estimate exposures of marine mammals to 
acoustic stimuli, NMFS is confident that SIO's approach to quantifying 
the EZs and buffer zones uses the best available scientific information 
and estimation methodologies. After considering this commend and 
evaluating the respective approaches for establishing EZs and buffer 
zones, NMFS had determined that SIO's approach and corresponding 
monitoring and mitigation measures will effect the least practicable 
impact on affected marine mammal species or stocks.
    Comment 2: The Commission recommends that NMFS, before issuing the 
requested IHA, (1) use species-specific maximum densities derived by 
multiplying the best density estimates by a precautionary correction 
factor and (2) re-estimate the anticipated number of takes using that 
precautionary approach.
    Response: For purposes of this IHA, NMFS is using the estimated 
densities provided in the applicant's application to estimate the 
number of authorized takes for SIO's seismic survey in the south-
eastern Pacific Ocean as NMFS is confident in the assumptions and 
calculations used to estimate density for this survey area. SIO used 
reported densities from five sources (i.e., Read et al., 2009; Ferguson 
and Barlow, 2003; Shiavini et al., 1999; Heinrich, 2006; and Galletti-
Vernazzani and Cabrera, 2009) that included habitat modeling for 
estimating cetacean densities based on numerous surveys in the eastern 
tropical Pacific for 11 cetacean species as well as a correction factor 
(0.5) for estimated densities from regional aerial and/or vessel 
surveys near the action area for dusky and Chilean dolphins as well as 
blue whales. Estimated densities that were obtained or assigned to each 
cetacean species have been corrected for both detectability and 
availability bias by the authors. SIO's use of these peer-reviewed, 
model-based, density estimates are the best available information to 
estimate density for the survey area and to estimate the number of 
authorized takes for the seismic survey in the south-eastern Pacific 
Ocean. The results of the associated monitoring reports show that the 
past use of the best estimates was appropriate and has not refuted 
NMFS's past determinations.
    Comment 3: The Commission recommends that, before issuing the 
requested IHA, NMFS prohibit the use of a 15 minute pause (i.e., 
extended shut-down) following the sighting of a mysticete or large 
odontocete in the exclusion zone and extend that pause to cover the 
maximum dive times of the species likely to be encountered prior to 
initiating ramp-up procedures.
    Response: NMFS would like to clarify the Commission's understanding 
of two conditions within the IHA--one related to turning on the airguns 
(ramp-up) after a shut-down due to a marine mammal sighting about to 
enter or within the EZ, and the other related to a ramp-up after an 
extended shut-down (i.e., the 15 minute pause due to equipment failure 
or routine maintenance).
    To clarify, the IHA requires the Melville to shut-down the airguns 
when a Protected Species Observer (PSO) sees a marine mammal within, 
approaching, or entering the relevant EZs for cetaceans or for 
pinnipeds. Following a shut-down, the Melville would only ramp-up the 
airguns if a marine mammal had exited the EZ or if the PSO had not seen 
the animals within the relevant EZ for 15 minutes for species with 
shorter dive times (i.e., small odontocetes and pinnipeds) or 30 
minutes for species with longer dive durations (i.e., mysticetes and 
large odontocetes, including sperm, pygmy sperm, dwarf sperm, killer, 
and beaked whales).
    NMFS believes that 30 minutes is an adequate length for the 
monitoring period prior to the ramp-up of the airgun array after 
sighting a mysticete or large odontocete for the following reasons:
     The Melville can transit roughly 5 knots; the ship would 
move 2.3 km (1.25 nmi) in 15 minutes or 4.6 km (2.5 nmi) in 30 minutes. 
At this distance, the

[[Page 27192]]

vessel will have moved 65.7 times (4.6 km/0.07 km) away from the 
distance of the original 180 dB EZ (70 m [229.7 ft] for two 105 in\3\ 
airguns) from the initial sighting. The vessel will have moved 115 
times (4.6 km/0.04 km) away from the distance of the 180 dB EZ (40 m 
[131.2 ft] for the two 45 in\3\ GI airguns) from the initial sighting.
     The relevant EZs for cetaceans and pinnipeds are 
relatively small (i.e., 70 m for cetaceans and 20 m [65.6 ft] for 
pinnipeds for the two 105 in\3\ GI airguns, and 40 m for cetaceans and 
10 m [32.8 ft] for pinnipeds for the two 45 in\3\ GI airguns). 
Extending the monitoring period for a relatively small EZ would not 
meaningfully increase the effectiveness of observing marine mammals 
approaching or entering the EZ for the full source level and would not 
further minimize the potential for take.
     Because a significant part of their movement is vertical 
(deep-diving), it is unlikely that a submerged mysticete or large 
odontocete would move in the same direction and speed (roughly 5 knots) 
with the vessel for 30 minutes. If a mysticete or large odontocete's 
maximum underwater dive time is 45 minutes, then there is only a one in 
three chance that the last random surfacing could occur within the 70 
or 40 m EZ.
     The PSOs are constantly monitoring the horizon and the EZs 
during the 30 minute period. On average, PSOs can observe to the 
horizon (10 km; 5.4 nmi) from the height of the Melville's observation 
deck and should be able to say with a reasonable degree of confidence 
whether a marine mammal would be encountered within this distance 
before resuming the two GI airgun operations at full power.
    Next, NMFS intends to clarify the monitoring period associated with 
an extended shut-down (i.e., the 15 minute pause due to equipment 
failure or routine maintenance). During active seismic operations, 
there are occasions when the Melville crew will need to temporarily 
shut-down the airguns due to equipment failure or for maintenance. 
Thus, an extended shut-down is not related to PSO detecting a marine 
mammal within, approaching, or entering the relevant EZs. However, the 
PSOs are still actively monitoring the relevant EZs for cetaceans and 
pinnipeds.
    In conclusion, NMFS has designed monitoring and mitigation measures 
to comply with the requirement that incidental take authorizations must 
include means of effecting the least practicable impact on marine 
mammal species and their habitat. The effectiveness of monitoring is 
science-based, and monitoring and mitigation measures must be 
``practicable.'' NMFS believes that the framework for visual monitoring 
will: (1) Be effective at spotting almost all species for which SIO has 
requested take, and (2) that imposing additional requirements, such as 
those suggested by the Commission, would not meaningfully increase the 
effectiveness of observing marine mammals approaching or entering the 
EZs and thus further minimize the potential for take.
    In the case of an extended shut-down, due to equipment failure or 
routine maintenance, the Melville's crew will turn on the airguns and 
follow the mitigation and monitoring procedures for a ramp-up after a 
period of 15 minutes. Again, the PSOs will monitor the full EZs for 
marine mammals and will implement a shut-down, if necessary. After 
considering this comment and evaluating the monitoring and mitigation 
requirements to be included in the IHA, NMFS has determined that SIO's 
approach and corresponding monitoring and mitigation measures will 
effect the least practicable impact on affected marine mammal species 
or stocks.
    Comment 4: The Commission recommends that NMFS work with the NSF to 
analyze the data collected during ramp-up procedures to help determine 
the effectiveness of those procedures as a mitigation measure for 
geophysical surveys.
    Response: NMFS acknowledges the Commission's request for an 
analysis of ramp-ups and will work with NSF and SIO to help identify 
the effectiveness of the mitigation measure for seismic surveys. The 
IHA requires that PSOs on the Melville make observations for 30 minutes 
prior to ramp-up, during all ramp-ups, and during all daytime seismic 
operations and record the following information when a marine mammal is 
sighted:
    (i) Species, group size, age/size/sex categories (if determinable), 
behavior when first sighted and after initial sighting, heading (if 
consistent), bearing and distance from the seismic vessel, sighting 
cue, apparent reaction of the airguns or vessel (e.g., none, avoidance, 
approach, paralleling, etc., and including responses to ramp-up), and 
behavioral pace; and
    (ii) Time, location, heading, speed, activity of the vessel 
(including number of airguns operating and whether in state of ramp-up 
or shut-down), Beaufort wind force and sea state, visibility, and sun 
glare.
    One of the primary purposes of monitoring is to result in 
``increased knowledge of the species'' and the effectiveness of 
required monitoring and mitigation measures; the effectiveness of ramp-
up as a mitigation measure and marine mammal reaction to ramp-up would 
be useful information in this regard. NMFS requires NSF and SIO to 
gather all data that could potentially provide information regarding 
the effectiveness of ramp-up as a mitigation measure in its monitoring 
report. However, considering the low numbers of marine mammal sightings 
and low number of ramp-ups it is unlikely that the information will 
result in any statistically robust conclusions for this particular 
seismic survey. Over the long term, these requirements may provide 
information regarding the effectiveness of ramp-up as a mitigation 
measure, provided PSOs detect animals during ramp-up.
    Description of the Marine Mammals in the Specified Geographic Area 
of the Specified Activity
    Thirty-two marine mammal species could occur in the south-eastern 
Pacific Ocean survey area. Twenty-eight cetacean species (22 
odontocetes and 6 mysticetes) and four pinniped species could occur in 
the south-eastern Pacific Ocean study area. Several of these species 
are listed as endangered under the U.S. Endangered Species Act of 1973 
(ESA; 16 U.S.C. 1531 et seq.), including the humpback (Megaptera 
novaeangliae), sei (Balaenoptera borealis), fin (Balaenoptera 
physalus), blue (Balaenoptera musculus), and sperm (Physeter 
macrocephalus) whale.
    An additional 12 cetacean species, although present in the wider 
south-eastern Pacific Ocean, likely would not be found in the proposed 
seismic survey area because their ranges in the survey area are 
extralimital, or they are typically found in coastal water. Southern 
right whales (Eubalaena australis) are listed as endangered under the 
ESA. Sightings are seen on rare occasions off the coasts of Peru and 
Chile (Aguayo et al., 1992; Santillan et al., 2004), although females 
with calves have been observed between June and October. Given the size 
of this population, estimated at 50 individuals, in Chile and Peru 
(IWC, 2007; ICW, 2007b) and the rarity of the species in the survey 
area, it is unlikely that individuals from this subpopulation will be 
encountered. Pygmy right whales (Caperea marginata) are rarely seen at 
sea, but are known from stranding records off Chile (Cabrera et al., 
2005). Little is known about Arnoux's beaked whale (Berardius arnuxii) 
as they are rarely seen, but typically they are found between the 
Antarctic continent and 34[deg] South. The

[[Page 27193]]

northernmost limit of their range overlaps with the survey area, but no 
records of their occurrence exist within the survey area. The spade 
toothed beaked whale (Mesoplodon traversii) and Shepherd's beaked whale 
(Tasmacetus shepherdi) are uncommon species, but individuals have been 
described from stranding records in the Juan Fernandez Archipelago in 
Chile (Reyes et al., 1996) approximately 700 km (378 nmi) west of the 
survey site. The ginkgo-toothed beaked whale (Mesoplodon ginkgodens), 
pygmy beaked whale (Mesoplodon peruvianus), and the long-beaked common 
dolphin (Delphinus capensis) are likely extralimital with distributions 
mostly north of the survey area. The Commerson's dolphin 
(Cephalorhynchus commersonii), hourglass dolphin (Lagenorhynchus 
cruciger), and southern bottlenose whale (Hyperoodon planifrons) are 
also extralimital in the survey area, but have a northernmost extent 
that is south of the survey area.
    No cetacean distribution and abundance studies have been conducted 
in the survey area. The closest distribution studies have been in the 
Eastern Tropical Pacific (ETP) and Patagonia, in southern Chile. 
Several other studies of marine mammal distribution and abundance have 
been conducted in the wider ETP. The most extensive regional 
distribution and abundance data come primarily from multi-year vessel 
surveys conducted by NMFS's Southwest Fisheries Science Center (SWFSC). 
The surveys were conducted during July to December in an area generally 
extending from 30[deg] North to 18[deg] South from the coastline to 
153[deg] West (Wade and Gerrodette, 1993; Ferguson and Barlow, 2001; 
Gerrodette et al., 2008; and Jackson et al., 2008).
    The marine mammals that occur in the survey area belong to three 
taxonomic groups: odontocetes (toothed whales and dolphins), mysticetes 
(baleen whales), and pinnipeds (seals, sea lions, and walrus). 
Cetaceans and pinnipeds are the subject of the IHA application to NMFS.
    Table 1 (below) presents information on the abundance, 
distribution, population status, conservation status, and density of 
the marine mammals that may occur in the survey area during May, 2012.

   Table 1--The Habitat, Regional Abundance, and Conservation Status of Marine Mammals That May Occur in or Near the Seismic Survey Area in the South-
                                                                  Eastern Pacific Ocean
                                          [See text and Tables 2 to 3 in SIO's application for further details]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                        Density (/1,000 km\2\)
                                                                                                                                               \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Mysticetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale (Megaptera             Mainly nearshore waters  \6\ 2,900..............  EN....................  D.....................           \4\ 0.8
 novaeangliae).                        and banks.              (SE Pacific)...........
Minke whale (Balaenoptera             Coastal................  \7\ 338,000............  NL....................  NC....................           \4\ 0.8
 acutorostrata).
Bryde's whale (Balaenoptera edeni)..  Pelagic and coastal....  130,008................  NL....................  NC....................              0.96
Sei whale (Balaenoptera borealis)...  Mostly pelagic.........  \8\ 11,000.............  EN....................  D.....................          \5\ 0.01
Fin whale (Balaenoptera physalus)...  Slope, mostly pelagic..  \9\ 15,178.............  EN....................  D.....................          \5\ 0.01
Blue whale (Balaenoptera musculus)..  Pelagic and coastal....  \10\ 1,415.............  EN....................  D.....................              2.44
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Odontocetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale (Physeter macrocephalus)  Usually deep pelagic,    \11\ 26,053............  EN....................  D.....................              3.95
                                       steep topography.
Pygmy sperm whale (Kogia breviceps).  Deep waters off shelf..  \12\ 150,000...........  NL....................  NC....................              0.03
Dwarf sperm whale (Kogia sima)......  Deep waters off shelf..  \12\ 150,000...........  NL....................  NC....................              0.03
Cuvier's beaked whale (Ziphius        Slope and pelagic......  \13\ 20,000............  NL....................  NC....................              0.80
 cavirostris).
Blainville's beaked whale             Slope and pelagic......  \14\ 25,300............  NL....................  NC....................              0.80
 (Mesoplodon densirostris).
Gray's beaked whale (Mesoplodon       Slope and pelagic......  NA.....................  NL....................  NC....................                NA
 grayi).
Hector's beaked whale (Mesoplodon     Slope and pelagic......  NA.....................  NL....................  NC....................                NA
 hectori).
Strap-toothed beaked whale            Slope and pelagic......  NA.....................  NL....................  NC....................                NA
 (Mesoplodon layardii).
Unidentified Mesoplodon spp.........  Slope and pelagic......  NA.....................  NL....................  NC....................              0.36
Rough-toothed dolphin (Steno          Mainly pelagic.........  107,633................  NL....................  NC....................              4.19
 bredanensis).
Bottlenose dolphin (Tursiops          Coastal, shelf, pelagic  335,834................  NL....................  NC; D--Western North               17.06
 truncatus).                                                                                                     Atlantic coastal.
Spinner dolphin (Stenella             Coastal and pelagic....  1,797,716..............  NL....................  NC....................             35.70
 longirostris).
Striped dolphin (Stenella             Off continental shelf..  964,362................  NL....................  NC; D--Eastern........             67.80
 coeruleoalba).

[[Page 27194]]

 
Short-beaked common dolphin           Shelf, pelagic, high     3,127,203..............  NL....................  NC....................            110.90
 (Delphinus delphis).                  relief.
Risso's dolphin (Grampus griseus)...  Shelf, slope, seamounts  110,457................  NL....................  NC....................             10.21
False killer whale (Pseudorca         Pelagic................  398,009................  NL; Proposed EN--       NC....................              0.39
 crassidens).                                                                            insular Hawaiian.
Killer whale (Orcinus orca).........  Widely distributed.....  \15\ 8,500.............  NL; EN--Southern        NC; D--Southern                     0.85
                                                                                         resident.               resident, AT1
                                                                                                                 transient.
Long-finned pilot whale               Shelf and pelagic......  \16\ 200,000...........  NL....................  NC....................             11.88
 (Globicephala melas).
Peale's dolphin (Lagenorhynchus       Coastal and shelf......  NA.....................  NL....................  NC....................           \4\ 0.8
 australis).
Dusky dolphin (Lagenorhynchus         Shelf and slope........  \17\ 7,252.............  NL....................  NC....................                37
 obscures).
Southern right whale dolphin          Pelagic................  NA.....................  NL....................  NC....................          \5\ 0.01
 (Lissodelphis peronni).
Chilean dolphin (Cephalorhynchus      Coastal and shelf......  \18\ < 10,000..........  NL....................  NC....................             11.11
 eutropia).
Burmeister's porpoise (Phocoena       Coastal................  NA.....................  NL....................  NC....................          \5\ 0.01
 spinipinnis).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
South American fur seal (Otaria       Coastal and shelf......  \19\ 30,000............  NL....................  NC....................                NA
 flavescens).
Juan Fernandez fur seal               Coastal and shelf......  \20\ 12,000............  NL....................  NC....................                NA
 (Arctocephalus philippii).
South American sea lion               Coastal and shelf......  \21\ 150,000...........  NL....................  NC....................                NA
 (Arctocephalus australis).
Southern elephant seal (Mirounga      Coastal and pelagic....  \22\ 650,000...........  NL....................  NC....................                NA
 leonina).
--------------------------------------------------------------------------------------------------------------------------------------------------------
N.A. = Not available or not assessed.
\1\ U.S. Endangered Species Act: EN = Endangered, T = Threatened, NL = Not listed.
\2\ U.S. Marine Mammal Protection Act: D = Depleted, NC = Not Classified.
\3\ Densities of other species (e.g., pinnipeds) presumably would b lower than the lowest density in Table 3 of the application.
\4\ Densities assigned an arbitrary density similar to densities reported for species that are uncommon in the survey area.
\5\ Densities assigned an arbitrarily low number for rare species with unconfirmed sightings in the survey area.
\6\ Southeast Pacific (Felix et al., 2005)
\7\ Estimated from Antarctic and common minke whales in South Pacific (Reilly, 2011).
\8\ Based on 2007 projection for southern hemisphere (IWC, 1996).
\9\ Based on 2007 projection for southern hemisphere (Reilly, 2011).
\10\ ETP (Wade and Gerrodette, 1993) excluded nursing area south of study area estimated at approximately 267 animals.
\11\ Eastern temperate North Pacific (Whitehead, 2002).
\12\ This abundance estimate is for Kogia sima and Kogia breviceps in ETP (Ferguson and Barlow, 2001).
\13\ ETP (Wade and Gerrodette, 1993).
\14\ This estimate includes all species of the genus Mesoplodon in the ETP (Ferguson and Barlow, 2001).
\15\ ETP (Ford, 2002).
\16\ Southern hemisphere population (Waring et al., 1997).
\17\ Patagonian coast population (Dans et al., 1997).
\18\ South-Eastern Pacific (Reeves et al., 2008).
\19\ Chile (Arias, Shreiber, and Rivas, 1998).
\20\ Juan Fernandez Archipelago population (Aurioles and Trillmich, 2008).
\21\ Peru and Chile (Campagna, 2008a).
\22\ Southern hemisphere (Campagna, 2009).

    Refer to Section III and IV of SIO's application for detailed 
information regarding the abundance and distribution, population 
status, and life history and behavior of these species and their 
occurrence in the project area. The application also presents how SIO 
calculated the estimated densities for the marine mammals in the survey 
area. NMFS has reviewed these data and determined them to be the best 
available scientific information for the purposes of the IHA.

Potential Effects on Marine Mammals

    Acoustic stimuli generated by the operation of the airguns, which 
introduce sound into the marine environment, may have the potential to 
cause Level B harassment of marine mammals in the survey area. The 
effects of sounds from airgun operations might include one or more of 
the following: Tolerance, masking of natural sounds, behavioral 
disturbance, temporary or permanent hearing impairment, or non-auditory 
physical or physiological effects (Richardson et al., 1995; Gordon et 
al., 2004; Nowacek et al., 2007; Southall et al., 2007).
    Permanent hearing impairment, in the unlikely event that it 
occurred, would

[[Page 27195]]

constitute injury, but temporary threshold shift (TTS) is not an injury 
(Southall et al., 2007). Although the possibility cannot be entirely 
excluded, it is unlikely that the proposed project would result in any 
cases of temporary or permanent hearing impairment, or any significant 
non-auditory physical or physiological effects. Based on the available 
data and studies described here, some behavioral disturbance is 
expected, but NMFS expects the disturbance to be localized and short-
term.
    The notice of the proposed IHA (77 FR 14744, March 13, 2012) 
included a discussion of the effects of sounds from airguns on 
mysticetes, odontocetes, and pinnipeds including tolerance, masking, 
behavioral disturbance, hearing impairment, and other non-auditory 
physical effects. NMFS refers the reader to SIO's application and EA 
for additional information on the behavioral reactions (or lack 
thereof) by all types of marine mammals to seismic vessels.

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

    NMFS included a detailed discussion of the potential effects of 
this action on marine mammal habitat, including physiological and 
behavioral effects on marine fish, fisheries, and invertebrates in the 
notice of the proposed IHA (77 FR 14744, March 13, 2012). The seismic 
survey will not result in any permanent impact on habitats used by the 
marine mammals in the proposed survey area, including the food sources 
they use (i.e. fish and invertebrates), and there will be no physical 
damage to any habitat. While NMFS anticipates that the specified 
activity may result in marine mammals avoiding certain areas due to 
temporary ensonification, this impact to habitat is temporary and 
reversible which was considered in further detail in the notice of the 
proposed IHA (77 FR 14744, March 13, 2012), as behavioral modification. 
The main impact associated with the activity will be temporarily 
elevated noise levels and the associated direct effects on marine 
mammals.
    Recent work by Andre et al. (2011) purports to present the first 
morphological and ultrastructural evidence of massive acoustic trauma 
(i.e., permanent and substantial alterations of statocyst sensory hair 
cells) in four cephalopod species subjected to low-frequency sound. The 
cephalopods, primarily cuttlefish, were exposed to continuous 40 to 400 
Hz sinusoidal wave sweeps (100% duty cycle and 1 s sweep period) for 
two hours while captive in relatively small tanks (one 2,000 liter [L, 
2 m\3\] and one 200 L [0.2 m\3\] tank). The received SPL was reported 
as 1575 dB re 1 [mu]Pa, with peak levels at 175 dB re 1 
[mu]Pa. As in the McCauley et al. (2003) paper on sensory hair cell 
damage in pink snapper as a result of exposure to seismic sound, the 
cephalopods were subjected to higher sound levels than they would be 
under natural conditions, and they were unable to swim away from the 
sound source.

Mitigation

    In order to issue an ITA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, and other means of effecting the least practicable adverse 
impact on such species or stock and its habitat, paying particular 
attention to rookeries, mating grounds, and areas of similar 
significance, and the availability of such species or stock for taking 
for certain subsistence uses.
    SIO has based development and evaluation of effectiveness of the 
mitigation measures, to be implemented under the IHA for the seismic 
survey, on the following:
    (1) Protocols used during previous SIO seismic research cruises as 
approved by NMFS;
    (2) Previous IHA applications and IHAs approved and authorized by 
NMFS; and
    (3) Recommended best practices in Richardson et al. (1995), Pierson 
et al. (1998), and Weir and Dolman, (2007).
    Planning Phase--The PIs worked with SIO and NSF to identify 
potential time periods to carry out the survey taking into 
consideration key factors such as environmental conditions (i.e., the 
seasonal presence of marine mammals), weather conditions, equipment, 
and optimal timing for other proposed seismic surveys using the 
Melville. Most marine mammal species are expected to occur in the area 
year-round, so altering the timing of the proposed survey likely would 
result in no net benefits for those species. Baleen whales are most 
common south of the survey area between February and June, whereas 
odontocetes were most commonly observed between October and November. 
After considering what energy source level was necessary to achieve the 
research goals, the PIs determined the use of the two GI airgun array 
with a maximum total volume of 210 in\3\ would be required; however, a 
lower energy source with a total volume of 90 in\3\ may be used. Given 
the research goals, location of the survey and associated deep water, 
this energy source level was viewed appropriate. The location of the 
survey was informed and adjusted based on the latest scientific 
information on the epicenter of the February 27, 2010 earthquake; 
survey location is critical for collecting the data for the overall 
research activity and meeting research objectives.
    To reduce the potential for disturbance of marine mammals from 
acoustic stimuli associated with the specified activities, the IHA 
requires SIO and/or its designees shall implement the following 
mitigation measures:
    (1) Exclusion zones;
    (2) Speed or course alteration;
    (3) Shut-down procedures; and
    (4) Ramp-up procedures.
    Exclusion Zones--Received sound levels have been modeled by L-DEO 
for a number of airgun configurations, including two 45 or two 105 
in\3\ GI airguns, in relation to distance and direction from the 
airguns (see Figure 2a and 2b of the IHA application). The models do 
not allow for bottom interactions, and are most directly applicable to 
deep water. Based on the modeling, estimates of the maximum distances 
from the source where sound levels are predicted to be 190, 180, and 
160 dB re 1 [mu]Pa (rms) in deep water were determined (see Table 2 
below).
    Empirical data concerning the 190, 180, and 160 dB (rms) distances 
were acquired for various airgun arrays based on measurements during 
the acoustic verification studies conducted by L-DEO in the northern 
GOM in 2003 (Tolstoy et al., 2004) and 2007 to 2008 (Tolstoy et al., 
2009). Results of the 36 airgun array are not relevant for the two GI 
airguns to be used in the survey. The empirical data for the 6, 10, 12, 
and 20 airgun arrays indicate that, for deep water, the L-DEO model 
tends to overestimate the received sound levels at a given distance 
(Tolstoy et al., 2004). Measurements were not made for the two GI 
airgun array in deep water, however, SIO proposes to use the EZ 
predicted by L-DEO's model for the GI airgun operations in deep water, 
although they are likely conservative give the empirical results for 
the other arrays.
    The 180 and 190 dB radii are shut-down criteria applicable to 
cetaceans and pinnipeds, respectively, as specified by NMFS (2000); 
these levels were used to establish the EZs. If the PSO detects marine 
mammal(s) within or about to enter the appropriate EZ, the airguns will 
be shut-down immediately.
    Table 2 summarizes the predicted distances at which sound levels 
(160, 180, and 190 dB [rms]) are expected to

[[Page 27196]]

be received from the two GI airgun array operating in deep water 
depths.

Table 2--Distances to Which Sound Levels >=190, 180, and 160 dB re 1 [mu]Pa (rms) Could Be Received in Deep Water During the Seismic Survey in the South-
                                                             Eastern Pacific Ocean, May 2012
                                                [Distances are based on model results provided by L-DEO]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                 Predicted RMS radii distances (m)
              Source and Volume                Tow depth (m)                Water depth (m)              -----------------------------------------------
                                                                                                              190 dB          180 dB          160 dB
--------------------------------------------------------------------------------------------------------------------------------------------------------
Two GI airguns (105 in\3\) (210 in\3\ total)               2  Deep (>1,000).............................              20              70             670
Two GI airguns (45 in\3\) (90 in\3\ total)..               2  Deep (>1,000 )............................              10              40             350
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Speed or Course Alteration--If a marine mammal is detected outside 
the EZ and, based on its position and the relative motion, is likely to 
enter the EZ, the vessel's speed and/or direct course could be changed. 
This would be done if operationally practicable while minimizing the 
effect on the planned science objectives. The activities and movements 
of the marine mammal (relative to the seismic vessel) will then be 
closely monitored to determine whether the animal is approaching the 
applicable EZ. If the animal appears likely to enter the EZ, further 
mitigative actions will be taken, i.e., either further course 
alterations or a shut-down of the seismic source. Typically, during 
seismic operations, the source vessel is unable to change speed or 
course and one or more alternative mitigation measures will need to be 
implemented.
    Shut-down Procedures--SIO will shut down the operating airgun(s) if 
a marine mammal is seen outside the EZ for the airgun(s), and if the 
vessel's speed and/or course cannot be changed to avoid having the 
animal enter the EZ, the seismic source will be shut-down before the 
animal is within the EZ. If a marine mammal is already within the EZ 
when first detected, the seismic source will be shut-down immediately.
    Following a shut-down, SIO will not resume airgun activity until 
the marine mammal has cleared the EZ. SIO will consider the animal to 
have cleared the EZ if:
     A PSO has visually observed the animal leave the EZ, or
     A PSO has not sighted the animal within the EZ for 15 
minutes for species with shorter dive durations (i.e., small 
odontocetes or pinnipeds), or 30 minutes for species with longer dive 
durations (i.e., mysticetes and large odontocetes, including sperm, 
killer, and beaked whales).
    Ramp-up Procedures--SIO will follow a ramp-up procedure when the 
airgun array begins operating after a specified period without airgun 
operations or when a shut-down has exceeded that period. For the 
present cruise, this period will be approximately 15 minutes under the 
IHA. SIO has used similar periods (approximately 15 minutes) during 
previous SIO surveys.
    Ramp-up will begin with a single GI airgun (45 or 105 in\3\). The 
second GI airgun (45 or 105 in\3\) will be added after five minutes. 
During ramp-up, the PSOs will monitor the EZ, and if marine mammals are 
sighted, SIO will implement a shut-down as though both GI airguns were 
operational.
    If the complete EZ has not been visible for at least 30 minutes 
prior to the start of operations in either daylight or nighttime, SIO 
will not commence the ramp-up. If one airgun has operated, ramp-up to 
full power will be permissible at night or in poor visibility, on the 
assumption that marine mammals will be alerted to the approaching 
seismic vessel by the sounds from the single airgun and could move away 
if they choose. A ramp-up from a shut-down may occur at night, but only 
where the EZ is small enough to be visible. SIO will not initiate a 
ramp-up of the airguns if a marine mammal is sighted within or near the 
applicable EZs during the day or close to the vessel at night.
    NMFS has carefully evaluated the applicant's mitigation measures 
and has considered a range of other measures in the context of ensuring 
that NMFS prescribes the means of effecting the least practicable 
adverse impact on the affected marine mammal species and stocks and 
their habitat. NMFS's evaluation of potential measures included 
consideration of the following factors in relation to one another:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure is expected to minimize adverse impacts 
to marine mammals;
    (2) The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned; and
    (3) The practicability of the measure for applicant implementation.
    Based on NMFS's evaluation of the applicant's measures, as well as 
other measures considered by NMFS or recommended by the public, NMFS 
has determined that the mitigation measures included in the IHA provide 
the means of effecting the least practicable impacts on marine mammal 
species or stocks and their habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance.

Monitoring and Reporting

    In order to issue an ITA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth ``requirements pertaining to 
the monitoring and reporting of such taking.'' The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for IHAs 
must include the suggested means of accomplishing the necessary 
monitoring and reporting that will result in increased knowledge of the 
species and of the level of taking or impacts on populations of marine 
mammals that are expected to be present in the action area.

Monitoring

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

Vessel-Based Visual Monitoring

    SIO's PSOs will be based aboard the seismic source vessel and will 
watch for marine mammals near the vessel during

[[Page 27197]]

daytime airgun operations and during any ramp-ups at night. PSOs will 
also watch for marine mammals near the seismic vessel for at least 30 
minutes prior to the ramp-up of airgun operations after an extended 
shut-down (i.e., greater than approximately 15 minutes for this 
proposed cruise). When feasible, PSOs will conduct observations during 
daytime periods when the seismic system is not operating for comparison 
of sighting rates and behavior with and without airgun operations and 
between acquisition periods. Based on PSO observations, the airguns 
will be shut-down when marine mammals are observed within or about to 
enter a designated EZ. The EZ is a region in which a possibility exists 
of adverse effects on animal hearing or other physical effects.
    During seismic operations in the south-eastern Pacific Ocean, three 
PSOs will be based aboard the Melville. SIO will appoint the PSOs with 
NMFS's concurrence. At least one PSO will monitor the EZs during 
seismic operations. Observations will take place during ongoing daytime 
operations and nighttime ramp-ups of the airguns. PSO(s) will be on 
duty in shifts of duration no longer than 4 hr. The vessel crew will 
also be instructed to assist in detecting marine mammals.
    The Melville is a suitable platform for marine mammal observations 
of protected species. The primary observer platform is located one deck 
below and forward of the bridge (02 level, 12.46 m [40.9 ft] above the 
waterline), affording relatively unobstructed 180[deg] forward view. A 
pair of Big-eye binoculars is mounted in this location. The open deck 
continues along both the port and starboard sides, and opens up to an 
aft deck stretching across the full width of the vessel. PSOs have 
views in a full 360[deg] by walking along this deck. In extremely 
inclement weather, the PSOs move on to the bridge (03 level, 15.5 m 
[50.6 ft] above the water line). There they will have a 360[deg] view 
through the windows.
    During daytime, the PSOs will scan the area around the vessel 
systematically with reticle binoculars (e.g., 7 x 50 Fujinon), Big-eye 
binoculars (25 x 150), optical range finders and with the naked eye. 
During darkness, night vision devices (NVDs) will be available, when 
required. The PSOs will be in wireless communication with the vessel's 
officers on the bridge and scientists in the vessel's operations 
laboratory, so they can advise promptly of the need for avoidance 
maneuvers or seismic source shut-down. When marine mammals are detected 
within or about to enter the designated EZ, the airguns will 
immediately be shut-down. The PSO(s) will continue to maintain watch to 
determine when the animal(s) are outside the EZ by visual confirmation. 
Airgun operations will not resume until the animal is confirmed to have 
left the EZ, or if not observed after 15 minutes for species with 
shorter dive durations (small odontocetes and pinnipeds) or 30 minutes 
for species with longer dive durations (mysticetes and large 
odontocetes, including sperm, killer, and beaked whales).

PSO Data and Documentation

    PSOs will record data to estimate the numbers of marine mammals 
exposed to various received sound levels and to document apparent 
disturbance reactions or lack thereof. Data will be used to estimate 
numbers of animals potentially `taken' by harassment (as defined in the 
MMPA). They will also provide information needed to order a shut-down 
of the airguns when a marine mammal is within or near the EZ. 
Observations will also be made during daytime periods when the Melville 
is underway without seismic operations (i.e., transits to, from, and 
through the study area) to collect baseline biological data.
    When a sighting is made, the following information about the 
sighting will be recorded:
    1. Species, group size, age/size/sex categories (if determinable), 
behavior when first sighted and after initial sighting, heading (if 
consistent), bearing and distance from seismic vessel, sighting cue, 
apparent reaction to the airguns or vessel (e.g., none, avoidance, 
approach, paralleling, etc.), and behavioral pace.
    2. Time, location, heading, speed, activity of the vessel, Beaufort 
sea state, visibility, and sun glare.
    The data listed under (2) will also be recorded at the start and 
end of each observation watch, and during a watch whenever there is a 
change in one or more of the variables.
    All observations as well as information regarding shut-downs of the 
seismic source, will be recorded in a standardized format. The data 
accuracy will be verified by the PSOs at sea, and preliminary reports 
will be prepared during the field program and summaries forwarded to 
the operating institution's shore facility and to NSF weekly or more 
frequently.
    Vessel-based observations by the PSO will provide the following 
information:
    1. The basis for real-time mitigation (airgun shut-down).
    2. Information needed to estimate the number of marine mammals 
potentially taken by harassment, which must be reported to NMFS.
    3. Data on the occurrence, distribution, and activities of marine 
mammals in the area where the seismic study is conducted.
    4. Information to compare the distance and distribution of marine 
mammals relative to the source vessel at times with and without seismic 
activity.
    5. Data on the behavior and movement patterns of marine mammals 
seen at times with and without seismic activity.
    SIO will submit a report to NMFS and NSF within 90 days after the 
end of the cruise. The report will describe the operations that were 
conducted and sightings of marine mammals near the operations. The 
report will provide full documentation of methods, results, and 
interpretation pertaining to all monitoring. The 90-day report will 
summarize the dates and locations of seismic operations, and all marine 
mammal sightings (dates, times, locations, activities, associated 
seismic survey activities). The report will also include estimates of 
the number and nature of exposures that could result in potential 
``takes'' of marine mammals by harassment or in other ways. After the 
report is considered final, it will be publicly available on the NMFS 
and NSF Web sites.
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by this IHA, 
such as an injury (Level A harassment), serious injury or mortality 
(e.g., ship-strike, gear interaction, and/or entanglement), SIO will 
immediately cease the specified activities and immediately report the 
incident to the Chief of the Permits and Conservation Division, Office 
of Protected Resources, NMFS at 301-427-8401 and/or by email to 
[email protected] and [email protected], and the NMFS 
Southwest Regional Stranding Coordinators ([email protected] and 
[email protected]). The report must include the following 
information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Name and type of vessel involved;
     Vessel's speed during and leading up to the incident;
     Description of the incident;
     Status of all sound source use in the 24 hours preceding 
the incident;
     Water depth;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;

[[Page 27198]]

     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).

Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS shall work with SIO to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. SIO may not resume their 
activities until notified by NMFS via letter or email, or telephone.
    In the event that SIO discovers an injured or dead marine mammal, 
and the lead PSO determines that the cause of the injury or death is 
unknown and the death is relatively recent (i.e., in less than a 
moderate state of decomposition as described in the next paragraph), 
SIO will immediately report the incident to the Chief of the Permits 
and Conservation Division, Office of Protected Resources, NMFS, at 301-
427-8401, and/or by email to [email protected] and 
[email protected], and the NMFS Southwest Regional Office (562-
980-4017) and/or by email to the Southwest Regional Stranding 
Coordinators ([email protected] and [email protected]). The 
report must include the same information identified in the paragraph 
above. Activities may continue while NMFS reviews the circumstances of 
the incident. NMFS will work with SIO to determine whether 
modifications in the activities are appropriate.
    In the event that SIO discovers an injured or dead marine mammal, 
and the lead PSO determines that the injury or death is not associated 
with or related to the activities authorized in the IHA (e.g., 
previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), SIO will report the incident to 
the Chief of the Permits and Conservation Division, Office of Protected 
Resources, NMFS, at 301-427-8401, and/or by email to 
[email protected] and [email protected], and the NMFS 
Southwest Regional Office (562-980-4017), and/or by email to the 
Southwest Regional Stranding Coordinators ([email protected] and 
[email protected]), within 24 hours of discovery. SIO will provide 
photographs or video footage (if available) or other documentation of 
the stranded animal sighting to NMFS and the Marine Mammal Stranding 
Network. Activities may continue while NMFS reviews the circumstances 
of the incident.

Estimated Take by Incidental Harassment

    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: Any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild [Level A harassment]; or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [Level B harassment].
    Only take by Level B harassment is anticipated and authorized as a 
result of the marine seismic survey in the south-eastern Pacific Ocean. 
Acoustic stimuli (i.e., increased underwater sound) generated during 
the operation of the seismic airgun array may have the potential to 
cause marine mammals in the survey area to be exposed to sounds at or 
greater than 160 dB or cause temporary, short-term changes in behavior. 
There is no evidence that the planned activities could result in 
injury, serious injury, or mortality within the specified geographic 
area for which NMFS has issued the IHA. Take by injury, serious injury, 
or mortality is thus neither anticipated nor authorized. NMFS has 
determined that the required mitigation and monitoring measures will 
minimize any potential risk for injury, serious injury, or mortality.
    The following sections describe SIO's methods to estimate take by 
incidental harassment and present the applicant's estimates of the 
numbers of marine mammals that could be affected during the seismic 
program. The estimates are based on a consideration of the number of 
marine mammals that could be disturbed appreciably by operations with 
the two GI airgun array to be used during approximately 1,810 km (977.3 
nmi) (includes primary and secondary lines and an additional 25 percent 
contingency) of survey lines in the south-eastern Pacific Ocean.
    SIO assumes that, during simultaneous operations of the airgun 
array and the other sources, any marine mammals close enough to be 
affected by the MBES and SBP would already be affected by the airguns. 
However, whether or not the airguns are operating simultaneously with 
the other sources, marine mammals are expected to exhibit no more than 
short-term and inconsequential responses to the MBES and SBP given 
their characteristics (e.g., narrow, downward-directed beam) and other 
considerations described previously. Such reactions are not considered 
to constitute ``taking'' (NMFS, 2001). Therefore, SIO provides no 
additional allowance for animals that could be affected by sound 
sources other than airguns.
    Extensive systematic ship-based surveys have been conducted by NMFS 
SWFSC for marine mammals in the ETP. SIO used densities from five 
sources:
    (1) SWFSC has recently developed habitat modeling as a method to 
estimate cetacean densities on a finer spatial scale than traditional 
line-transect analyses by using a continuous function of habitat 
variables, e.g., sea surface temperature, depth, distance from shore, 
and prey density (Barlow et al., 2009). For the ETP, the models are 
based on data from 12 SWFSC ship-based cetacean and ecosystem 
assessment surveys conducted during July to December from 1986 to 2006. 
The models have been incorporated into a web-based Geographic 
Information System (GIS) developed by Duke University's Department of 
Defense Strategic Environmental Research and Development Program 
(SERDP) team in close collaboration with the SWFSC SERDP team (Read et 
al., 2009). For 11 cetacean species in the model, SIO used the GIS to 
obtain mean densities near the survey area, i.e., in a rectangle 
bounded by 4[deg] to 12[deg] South and 75[deg] to 85[deg] West, which 
was the south-eastern extent of the model;
    (2) For species sighted in SWFSC surveys whose sample sizes were 
too small to model density, SIO used densities from the surveys 
conducted during summer and fall 1986 to 1996, as summarized by 
Ferguson and Barlow (2001). Densities were calculated from Ferguson and 
Barlow (2003) for 5[deg] x 5[deg] blocks that include the proposed 
survey areas and corridors: Blocks 139, 159, 160, 200, 201, 202, 212, 
213, and 219. Those blocks included 27,275 km (14727.3 nmi) of survey 
effort in Beaufort sea states 0 to 5, and 2,564 km (1,384.5 nmi) of 
survey effort in Beaufort sea states 0 to 2. Densities were obtained 
for an additional five species that were sighted in one or more of 
those blocks;
    (3) For dusky dolphins, SIO used the mean densities reported for 
Area A from aerial surveys in North and Central Patagonia (Shiavini et 
al., 1999), corrected for [fnof](0), but not g(0). Since the closest 
density estimates were taken south of the survey area, where dusky 
dolphin abundance is higher, SIO used 10 percent of the reported 
density to account for the decreased abundance of dusky dolphins in the 
proposed survey area;
    (4) For Chilean dolphins, SIO used the estimated density of Chilean

[[Page 27199]]

dolphins in Patagonia from Heinrich (2006). The extralimital, offshore 
distribution of Chilean dolphins in the survey area was corrected for 
by taking 1 percent of the densities reported by Heinrich (2006);
    (5) For blue whales, SIO used the densities reported by Galletti-
Vernazzani and Cabrera (2009) from aerial surveys in Patagonia in March 
2007 and April in 2009 that took place south of the survey site 
(39[deg] South to 44[deg] South). The density estimates were corrected 
for [fnof](0) and g(0). Given the higher abundance of blue whales south 
of the survey site, SIO corrected the reported density for the survey 
area by reducing the density by 50 percent.
    For two species for which there are only unconfirmed sightings in 
the region, the sei and fin whale, arbitrary low densities (equal to 
the density of the species with the lowest calculated density) were 
assigned. The same arbitrary low density was assigned to southern right 
whale dolphins and Burmeister's porpoise, where no confirmed sightings 
were made within the survey region. In addition, there were no density 
estimates available for humpback whales, minke whales, and Peale's 
dolphins, but confirmed sightings have been made near the survey area. 
SIO arbitrarily assigned a density estimate of 0.8 animals/1,000 km\2\, 
which was similar to the densities reported for uncommon species in the 
area.
    Oceanographic conditions, including occasional El Nino and La Nina 
events, influence the distribution and numbers of marine mammals 
present in the ETP and SEP, resulting in considerable year-to-year 
variation in the distribution and abundance of many marine mammal 
species (e.g., Escorza-Trevino, 2009). Thus, for some species the 
densities derived from recent surveys may not be representative of 
densities that will be encountered during the seismic survey.
    SIO used estimated densities (see Table 3 of the application) for 
each cetacean species likely to occur in the study area, i.e., species 
for which SIO obtained or assigned densities. The densities had been 
corrected, by the authors, for both trackline detectability and 
availability bias. Trackline detection probability bias is associated 
with diminishing sightability with increasing lateral distance from the 
trackline, and is measured by [fnof](0). Availability bias refers to 
the fact that there is less-than-100% probability of sighting an animal 
that is present along the survey trackline [fnof](0), and it is 
measured by g(0). Corrections for [fnof](0) and g(0) were made where 
mentioned above. The densities are given in Table 3 of SIO's IHA 
application.
    SIO's estimates of exposures to various sound levels assume that 
the surveys will be fully completed; in fact, the ensonified areas 
calculated using the planned number of line-km have been increased by 
25 percent to accommodate turns, lines that may need to be repeated, 
equipment testing, etc. As is typical during offshore ship surveys, 
inclement weather and equipment malfunctions are likely to cause delays 
and may limit the number of useful line-kilometers of seismic 
operations that can be undertaken. Furthermore, any marine mammal 
sightings within or near the designated EZs will result in the shut-
down of seismic operations as a mitigation measure. Thus, the following 
estimates of the numbers of marine mammals potentially exposed to sound 
levels of 160 dB re 1 [mu]Pa (rms) are precautionary and probably 
overestimate the actual numbers of marine mammals that might be 
involved. These estimates also assume that there will be no weather, 
equipment, or mitigation delays, which is highly unlikely.
    SIO estimated the number of different individuals that may be 
exposed to airgun sounds with received levels greater than or equal to 
160 dB re 1 [mu]Pa (rms) on one or more occasions by considering the 
total marine area that would be within the 160 dB radius around the 
operating airgun array on at least one occasion, along with the 
expected density of marine mammals in the area. The seismic lines are 
not in close proximity, which minimizes the number of times an 
individual marine mammal may be exposed during the survey; the area 
including the overlap is only 1.2 times the area excluding overlap.
    The numbers of different individuals potentially exposed to greater 
than or equal to 160 dB (rms) were calculated by multiplying the 
expected species density times the anticipated area to be ensonified 
during airgun operations. The area expected to be ensonified was 
determined by entering the planned survey lines into a MapInfo GIS, 
using the GIS to identify the relevant areas by ``drawing'' the 
applicable 160 dB buffer (see Table 1 of the IHA application) around 
each seismic line, and then calculating the total area within the 
buffers. Areas where overlap occurred (because of crossing lines) were 
included only once when estimating the number of individuals exposed.
    Applying the approach described above, approximately 1,448.4 km\2\ 
(422.3 nmi\2\) would be within the 160 dB isopleth on one or more 
occasions during the survey (including primary and secondary lines). 
The total ensonified area used to calculate estimated numbers exposed 
was approximately 1,810.5 km\2\ [527.9 nmi\2\] and includes the 
additional 25 percent increase in the calculated area for contingency. 
Because this approach does not allow for turnover in the marine mammal 
populations in the study area during the course of the survey, the 
actual number of individuals exposed could be underestimated, although 
the conservative (i.e., probably overestimated) line-kilometer 
distances used to calculate the area may offset this. Also, the 
approach assumes that no cetaceans will move away from or toward the 
trackline as the Melville approaches in response to increasing sound 
levels prior to the time the levels reach 160 dB. Another way of 
interpreting the estimates that follow is that they represent the 
number of individuals that are expected (in the absence of a seismic 
program) to occur in the waters that will be exposed to greater than or 
equal to 160 dB re 1 [mu]Pa (rms).
    Table 3 (Table 3 of the IHA application) shows the estimates of the 
number of different individual marine mammals that potentially could be 
exposed to greater than or equal to 160 dB re 1 [mu]Pa (rms) during the 
seismic survey if no animals moved away from the survey vessel. The 
requested take authorization is given in Table 3 (below; the far right 
column of Table 3 of the IHA application). For ESA listed species, the 
requested take authorization has been increased to the mean group size 
in southern Chile where available (Viddi et al., 2010) or the ETP (Wade 
and Gerodette, 1993), where the calculated number of individuals 
exposed was between 0.05 and the mean group size (i.e., for sei, fin, 
humpback, and sperm whales). For species not listed under the ESA that 
could occur in the study area, the requested take authorization has 
been increased to the mean group size in the ETP (Wade and Gerodette, 
1993) or southern Chile (Viddi et al., 2010); Zamorano-Abramson et al., 
2010) in cases where the calculated number of individuals exposed was 
between one and the mean group size. For delphinids where typically 
large group sizes are encountered, the requested take authorization was 
increased to the mean group size in southern Chile (Aguauo et al., 
1998; Viddi et al., 2010; Zamarano-Abramson et al., 2010) if the 
calculated number was greater than one, but less than the mean group 
size.
    The best estimate of the number of individual cetaceans that could 
be

[[Page 27200]]

exposed to seismic sounds with received levels greater than or equal to 
160 dB re 1 [mu]Pa (rms) during the survey is 561 (see Table 3 of the 
IHA application). That total includes: 1 humpback, 1 minke, 2 Bryde's, 
4 blue, and 7 sperm whales, 1 Cuvier's, 1 Blainville's, and 1 
unidentified Mesoplodon beaked whale, 15 rough-toothed, 72 bottlenose, 
134 spinner, 123 striped, 254 short-beaked common, 4 Peale's, 67 dusky, 
and 4 Chilean dolphins, and 1 false killer, 2 killer, and 22 long-
finned pilot whales, which would represent less than 1% of the regional 
populations for any of the respective species. Most (96.4%) of the 
cetaceans potentially exposed are delphinids; rough-toothed, short-
beaked common, striped, spinner, bottlenose, Risso's, and dusky 
dolphins and long-finned pilot whales are estimated to be the most 
common species in the study area. Due to the extralimital distribution 
of pinnipeds in the study area, no pinnipeds are expected to be 
encountered during the survey. The authorized incidental take numbers 
of humpback (3), minke (2), sperm (8), Cuvier's (2), Blainville's (2), 
Mesoplodon spp. (2), false killer (10), and killer (10) whales, as well 
as rough-toothed (15), bottlenose (72), spinner (134), Risso's (254), 
and Peale's (4) dolphins has been requested from the calculated 
potential takes to account for mean group size (Jefferson et al., 
2008).

 Table 3--Estimates of the Possible Numbers of Marine Mammals Exposed to Different Sound Levels >=160 dB During
                     SIO's Seismic Survey in the South-Eastern Pacific Ocean During May 2012
----------------------------------------------------------------------------------------------------------------
                                                                                                  Approximate
                                   Estimated number                                               percent of
                                    of individuals      Authorized take     Incidental take        regional
             Species               exposed to sound        requested          authorized       population  (for
                                   levels  >=160 dB                                             incidental take
                                    re 1 [mu]Pa \1\                                             authorized) \2\
----------------------------------------------------------------------------------------------------------------
                                                   Mysticetes
----------------------------------------------------------------------------------------------------------------
Humpback whale..................                   1                 * 3                   3                 0.1
Minke whale.....................                   1                 * 2                   2               <0.01
Bryde's whale...................                   2                   2                   2               <0.01
Sei whale.......................                   0                   0                   0                  NA
Fin whale.......................                   0                   0                   0                  NA
Blue whale......................                   4                   4                   4                 0.3
----------------------------------------------------------------------------------------------------------------
                                                   Odontocetes
----------------------------------------------------------------------------------------------------------------
Sperm whale.....................                   7                 * 8                   8                0.03
Pygmy sperm whale...............                   0                   0                   0                  NA
Dwarf sperm whale...............                   0                   0                   0                  NA
Cuvier's beaked whale...........                   1                   1                   2                0.01
Blainville's beaked whale.......                   1                   1                   2               <0.01
Gray's beaked whale.............                   0                   0                   0                  NA
Hector's beaked whale...........                   0                   0                   0                  NA
Strap-toothed beaked whale......                   0                   0                   0                  NA
Unidentified Mesoplodon spp.....                   1                   1                   2                  NA
Rough-toothed dolphin...........                   8                * 15                  15                0.01
Bottlenose dolphin..............                  31                * 72                  72                0.02
Spinner dolphin.................                  65               * 134                 134               <0.01
Striped dolphin.................                 123                 123                 123                0.01
Short-beaked common dolphin.....                 201               * 254                 254                0.01
Risso's dolphin.................                  18                  18                  18                0.02
False killer whale..............                   1                   1                  10               <0.01
Killer whale....................                   2                   2                  10                0.12
Long-finned pilot whale.........                  22                  22                  22                0.01
Peale's dolphin.................                   1               \*\ 4                   4                  NA
Dusky dolphin...................                  67                  67                  67                0.92
Southern right whale dolphin....                   0                   0                   0                  NA
Chilean dolphin.................                   4                   4                   4                 0.4
Burmeister's porpoise...........                   0                   0                   0                  NA
----------------------------------------------------------------------------------------------------------------
                                                    Pinnipeds
----------------------------------------------------------------------------------------------------------------
South American fur seal.........                   0                   0                   0                  NA
Juan Fernandez fur seal.........                   0                   0                   0                  NA
South American sea lion.........                   0                   0                   0                  NA
Southern elephant seal..........                   0                   0                   0                  NA
----------------------------------------------------------------------------------------------------------------
\1\ Estimates are based on densities from Table 1 (Table 3 of the IHA application) and ensonified areas
  (including 25% contingency) for 160 dB of 1,810.5 km \2\.
\2\ Regional population size estimates are from Table 2 (see Table 2 of the IHA application); NA means not
  available.
* Requested authorized take was increased to mean group size for delphinids if calculated numbers were between 1
  and mean group size, and increased to the mean group size if calculated vales were greater than 0.05 for
  endangered species.
N.A. Not available or not assessed.


[[Page 27201]]

Encouraging and Coordinating Research

    SIO and NSF will coordinate the planned marine mammal monitoring 
program associated with the seismic survey in the south-eastern Pacific 
Ocean with any parties that may have or express an interest in the 
seismic survey area. SIO and NSF have coordinated, and will continue to 
coordinate, with other applicable Federal agencies as required, and 
will comply with their requirements. Pursuant to IHA requirements, SIO 
will submit a monitoring report to NMFS 90 days after the survey. PSO 
data collected during the survey will be submitted to OBIS Seamap and 
will be made available on the NSF Web site for interested parties and 
researchers.

Negligible Impact and Small Numbers Analysis and Determination

    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as ``* * * 
an impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.'' In making a negligible impact determination, 
NMFS evaluated factors such as:
    (1) The number of anticipated injuries, serious injuries, or 
mortalities;
    (2) The number, nature, and intensity, and duration of Level B 
harassment (all relatively limited);
    (3) The context in which the takes occur (i.e., impacts to areas of 
significance, impacts to local populations, and cumulative impacts when 
taking into account successive/contemporaneous actions when added to 
baseline data);
    (4) The status of stock or species of marine mammals (i.e., 
depleted, not depleted, decreasing, increasing, stable, and impact 
relative to the size of the population);
    (5) Impacts on habitat affecting rates of recruitment/survival; and
    (6) The effectiveness of monitoring and mitigation measures (i.e., 
the manner and degree in which the measure is likely to reduce adverse 
impacts to marine mammals, the likely effectiveness of the measures, 
and the practicability of implementation).
    For reasons stated previously in this document, and in the notice 
of the proposed IHA (77 FR 14744, March 13, 2012), the specified 
activities associated with the marine seismic survey are not likely to 
cause PTS, or other non-auditory injury, serious injury, or death 
because:
    (1) The likelihood that, given sufficient notice through relatively 
slow ship speed, marine mammals are expected to move away from a noise 
source that is annoying prior to its becoming potentially injurious;
    (2) The potential for temporary or permanent hearing impairment is 
relatively low and would likely be avoided through the incorporation of 
the required monitoring and mitigation measures (described above);
    (3) The fact that pinnipeds would have to be closer than 10 m (32.8 
ft) (for the 45 in\3\) or 20 m (65.6 ft) (for the 105 in\3\) in deep 
water when the two GI airgun array is in use at 2 m (6.6 ft) tow depth 
from the vessel to be exposed to levels of sound believed to have even 
a minimal chance of causing PTS;
    (4) The fact that cetaceans would have to be closer than 40 m 
(131.2 ft) (for the 45 in\3\) or 70 m (229.7 ft) (for the 105 in\3\)in 
deep water when the two GI airgun array is in 2 m tow depth from the 
vessel to be exposed to levels of sound believed to have even a minimal 
chance of causing PTS; and
    (5) The likelihood that marine mammal detection ability by trained 
PSOs is high at close proximity to the vessel.
    No injuries, serious injuries, or mortalities are anticipated to 
occur as a result of SIO's planned marine seismic survey, and none are 
authorized by NMFS. Only short-term, behavioral disturbance is 
anticipated to occur due to the brief and sporadic duration of the 
survey activities. Table 3 in this document outlines the number of 
Level B harassment takes that are anticipated as a result of the 
activities. Due to the nature, degree, and context of Level B 
(behavioral) harassment anticipated and described (see Potential 
Effects on Marine Mammals section above) in this notice, the activity 
is not expected to impact rates of recruitment or survival for any 
affected species or stock. Additionally, the seismic survey will not 
adversely impact marine mammal habitat.
    Many animals perform vital functions, such as feeding, resting, 
traveling, and socializing, on a diel cycle (i.e., 24 hr cycle). 
Behavioral reactions to noise exposure (such as disruption of critical 
life functions, displacement, or avoidance of important habitat) are 
more likely to be significant if they last more than one diel cycle or 
recur on subsequent days (Southall et al., 2007). While seismic 
operations are anticipated to occur on consecutive days, the entire 
duration of the survey is not expected to last more than 15 days and 
the Melville will be continuously moving along planned tracklines. 
Therefore, the seismic survey will be increasing sound levels in the 
marine environment surrounding the vessel for several weeks in the 
study area.
    Of the 32 marine mammal species under NMFS jurisdiction that are 
known to or likely to occur in the study area, five are listed as 
endangered under the ESA: humpback, sei, fin, blue, and sperm whale. 
These species are also considered depleted under the MMPA. There is 
generally insufficient data to determine population trends for the 
other depleted species in the study area. To protect these animals (and 
other marine mammals in the study area), SIO must cease or reduce 
airgun operations if animals enter designated zones. No injury, serious 
injury, or mortality is expected to occur and due to the nature, 
degree, and context of the Level B harassment anticipated, the activity 
is not expected to impact rates of recruitment or survival.
    As mentioned previously, NMFS estimates that 20 species of marine 
mammals under its jurisdiction could be potentially affected by Level B 
harassment over the course of the IHA. For each species, these numbers 
are small (each less than one percent) relative to the regional 
population size. The population estimates for the marine mammal species 
that may be taken by Level B harassment were provided in Table 1 of 
this document.
    NMFS's practice has been to apply the 160 dB re 1 [micro]Pa (rms) 
received level threshold for underwater impulse sound levels to 
determine whether take by Level B harassment occurs. Southall et al. 
(2007) provide a severity scale for ranking observed behavioral 
responses of both free-ranging marine mammals and laboratory subjects 
to various types of anthropogenic sound (see Table 4 in Southall et al. 
[2007]).
    NMFS has determined, provided that the aforementioned mitigation 
and monitoring measures are implemented, that the impact of conducting 
a marine seismic survey in the south-eastern Pacific Ocean, May, 2012, 
may result, at worst, in a temporary modification in behavior and/or 
low-level physiological effects (Level B harassment) of small numbers 
of certain species of marine mammals. See Table 3 (above) for the 
requested authorized take numbers of cetaceans and pinnipeds.
    While behavioral modifications, including temporarily vacating the 
area during the operation of the airgun(s), may be made by these 
species to avoid the resultant acoustic disturbance, the availability 
of alternate areas within these areas and the short and sporadic 
duration of the research activities, have led NMFS to determine that 
this action will have a negligible impact on the

[[Page 27202]]

species in the specified geographic region.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the mitigation and monitoring 
measures, NMFS finds that SIO's planned research activities, will 
result in the incidental take of small numbers of marine mammals, by 
Level B harassment only, and that the total taking from the marine 
seismic survey will have a negligible impact on the affected species or 
stocks of marine mammals; and that impacts to affected species or 
stocks of marine mammals have been mitigated to the lowest level 
practicable.

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

    Section 101(a)(5)(D) also requires NMFS to determine that the 
authorization will not have an unmitigable adverse effect on the 
availability of marine mammal species or stocks for subsistence use. 
There are no relevant subsistence uses of marine mammals in the study 
area (offshore waters of the south-eastern Pacific Ocean off of Chile) 
that implicate MMPA section 101(a)(5)(D).

Endangered Species Act

    Of the species of marine mammals that may occur in the survey area, 
several are listed as endangered under the ESA, including the humpback, 
sei, fin, blue, and sperm whale. Under section 7 of the ESA, NSF 
initiated and engaged in formal consultation with the NMFS, Office of 
Protected Resources, Endangered Species Act Interagency Cooperation 
Division, on this seismic survey. NMFS's Office of Protected Resources, 
Permits and Conservation Division, also initiated and engaged in formal 
consultation under section 7 of the ESA with NMFS's Office of Protected 
Resources, Endangered Species Act Interagency Cooperation Division, on 
the issuance of an IHA under section 101(a)(5)(D) of the MMPA for this 
activity. These two consultations were consolidated and addressed in a 
single BiOp addressing the direct and indirect effects of these 
interdependent actions. In May, 2012, NMFS issued a BiOp and concluded 
that the action and issuance of the IHA are not likely to jeopardize 
the continued existence of cetaceans, pinnipeds, and sea turtles and 
included an Incidental Take Statement (ITS) incorporating the 
requirements of the IHA as Terms and Conditions. Compliance with those 
Relevant Terms and Conditions of the ITS is likewise a mandatory 
requirement of the IHA. The BiOp also concluded that designated 
critical habitat of these species does not occur in the action area and 
would not be affected by the survey.

National Environmental Policy Act (NEPA)

    To meet NMFS's NEPA requirements for the issuance of an IHA to SIO, 
NMFS prepared an ``Environmental Assessment on the Issuance of an 
Incidental Harassment Authorization to the Scripps Institution of 
Oceanography to Take Marine Mammals by Harassment Incidental to a 
Marine Geophysical Survey in the South-Eastern Pacific Ocean, May, 
2012.'' This EA incorporates the NSF's ``National Environmental Policy 
Act Analysis Pursuant to Executive Order 12114 of a Marine Geophysical 
Survey by the R/V Melville in the South-Eastern Pacific Ocean, May 
2012'' and an associated report (Report) prepared by LGL for NSF and 
SIO titled ``Final Environmental Analysis of a Marine Geophysical 
Survey by the R/V Melville in the South-Eastern Pacific Ocean off 
Chile, May 2012,'' by reference pursuant to 40 CFR 1502.21 and NOAA 
Administrative Order (NAO) 216-6 Sec.  5.09(d). NMFS has fully 
evaluated the potential direct, indirect, and cumulative effects on the 
human environment prior to making a final decision on the IHA 
application and deciding whether or not to issue a Finding of No 
Significant Impact (FONSI). After considering the final EA, the 
information in the IHA application, BiOp, and the Federal Register 
notice, as well as public comments, NMFS has determined that the 
issuance of the IHA is not likely to result in significant impacts on 
the human environment and has prepared a FONSI. An Environmental Impact 
Statement is not required and will not be prepared for the action. 
Authorization
    NMFS has issued an IHA to SIO for the take, by Level B harassment, 
of small numbers of marine mammals incidental to conducting a marine 
seismic survey in the south-eastern Pacific Ocean, provided the 
previously mentioned mitigation, monitoring, and reporting requirements 
are incorporated.

    Dated: May 2, 2012.
Helen M. Golde,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2012-11207 Filed 5-8-12; 8:45 am]
BILLING CODE 3510-22-P