Notice2023-23298
Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Geophysical Surveys Related to Oil and Gas Activities in the Gulf of Mexico
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
October 23, 2023
Effective
October 17, 2023
Issuing agencies
Commerce DepartmentNational Oceanic and Atmospheric Administration
Abstract
In accordance with the Marine Mammal Protection Act (MMPA), as amended, its implementing regulations, and NMFS' MMPA Regulations for Taking Marine Mammals Incidental to Geophysical Surveys Related to Oil and Gas Activities in the Gulf of Mexico, notification is hereby given that a Letter of Authorization (LOA) has been issued to WesternGeco for the take of marine mammals incidental to geophysical survey activity in the Gulf of Mexico.
Full Text
<html>
<head>
<title>Federal Register, Volume 88 Issue 203 (Monday, October 23, 2023)</title>
</head>
<body><pre>
[Federal Register Volume 88, Number 203 (Monday, October 23, 2023)]
[Notices]
[Pages 72739-72743]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2023-23298]
-----------------------------------------------------------------------
DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[RTID 0648-XD468]
Taking and Importing Marine Mammals; Taking Marine Mammals
Incidental to Geophysical Surveys Related to Oil and Gas Activities in
the Gulf of Mexico
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice. Issuance of letter of authorization.
-----------------------------------------------------------------------
SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA), as
amended, its implementing regulations, and NMFS' MMPA Regulations for
Taking Marine Mammals Incidental to Geophysical Surveys Related to Oil
and Gas Activities in the Gulf of Mexico, notification is hereby given
that a Letter of Authorization (LOA) has been issued to WesternGeco for
the take of marine mammals incidental to geophysical survey activity in
the Gulf of Mexico.
DATES: The LOA is effective from October 17, 2023 through April 30,
2024.
ADDRESSES: The LOA, LOA request, and supporting documentation are
available online at: <a href="https://www.fisheries.noaa.gov/action/incidental-take-authorization-oil-and-gas-industry-geophysical-survey-activity-gulf-mexico">https://www.fisheries.noaa.gov/action/incidental-take-authorization-oil-and-gas-industry-geophysical-survey-activity-gulf-mexico</a>. In case of problems accessing these documents, please call
the contact listed below (see FOR FURTHER INFORMATION CONTACT).
FOR FURTHER INFORMATION CONTACT: Jenna Harlacher, Office of Protected
Resources, NMFS, (301) 427-8401.
SUPPLEMENTARY INFORMATION:
Background
Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.)
direct the Secretary of Commerce to allow, upon request, the
incidental, but not intentional, taking of small numbers of marine
mammals by U.S. citizens who engage in a specified activity (other than
commercial fishing) within a specified geographical region if certain
findings are made and either regulations are issued or, if the taking
is limited to harassment, a notice of a proposed authorization is
provided to the public for review.
An authorization for incidental takings shall be granted if NMFS
finds that the taking will have a negligible impact on the species or
stock(s), will not have an unmitigable adverse impact on the
availability of the species or stock(s) for subsistence uses (where
relevant), and if the permissible methods of taking and requirements
pertaining to the mitigation, monitoring and reporting of such takings
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103
as an impact resulting from the specified activity that cannot be
reasonably expected to, and is not reasonably likely to, adversely
affect the species or stock through effects on annual rates of
recruitment or survival.
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).
On January 19, 2021, we issued a final rule with regulations to
govern the unintentional taking of marine mammals incidental to
geophysical survey activities conducted by oil and gas industry
operators, and those persons authorized to conduct activities on their
behalf (collectively ``industry operators''), in U.S. waters of the
Gulf of Mexico (GOM) over the course of 5 years (86 FR 5322, January
19, 2021). The rule was based on our findings that the total taking
from the specified activities over the 5-year period will have a
negligible impact on the affected species or stock(s) of marine mammals
and will not have an unmitigable adverse impact on the availability of
those species or stocks for subsistence uses. The rule became effective
on April 19, 2021.
Our regulations at 50 CFR 217.180 et seq. allow for the issuance of
LOAs to industry operators for the incidental take of marine mammals
during geophysical survey activities and prescribe the permissible
methods of taking and other means of effecting the least practicable
adverse impact on marine mammal species or stocks and their habitat
(often referred to as mitigation), as well as requirements pertaining
to the monitoring and reporting of such taking. Under Sec. 217.186
(e), issuance of an LOA shall be based on a determination that the
level of taking will be consistent with the findings made for the total
taking allowable under these regulations and a determination that the
amount of take
[[Page 72740]]
authorized under the LOA is of no more than small numbers.
Summary of Request and Analysis
WesternGeco plans to conduct a three-dimensional (3D) ocean bottom
node (OBN) survey in the Green Canyon and Walker Ridge protraction
areas, including approximately 795 lease blocks. Approximate water
depths of the survey area range from 1,000 to 3,000 meters (m). See
section F of the LOA application for a map of the area.
WesternGeco anticipates using two source vessels, towing low-
frequency airgun sources known as Gemini (also referred to as a dual
barbell source) or conventional airgun sources consisting of 28
elements, with a total volume of 5,240 cubic inches (in\3\). Please see
WesternGeco's application for additional detail.
The Gemini source was not included in the acoustic exposure
modeling developed in support of the rule. However, our rule
anticipated the possibility of new and unusual technologies (NUT) and
determined they would be evaluated on a case-by case basis (86 FR 5322,
5442, January 19, 2021). This source was previously evaluated as a NUT
in 2020 (prior to issuance of the 2021 final rule) pursuant to the
requirements of NMFS' 2020 Biological Opinion on BOEM's Gulf of Mexico
oil and gas program as well as the issuance of the rule. An associated
report produced by Jasco Applied Sciences (Grooms et al., 2019)
provides information related to the acoustic output of the Gemini
source, which informs our evaluation here.
The Gemini source operates on the same basic principles as a
traditional airgun source in that it uses compressed air to create a
bubble in the water column which then goes through a series of
collapses and expansions creating primarily low-frequency sounds.
However, the Gemini source consists of one physical element with two
large chambers of 4,000 (in\3\) each (total volume of 8,000 in\3\).
This creates a larger bubble resulting in more of the energy being
concentrated in low frequencies, with a fundamental frequency of 3.7
Hertz. In addition to concentrating energy at lower frequencies, the
Gemini source is expected to produce lower overall sound levels than
the conventional airgun proxy source. The number of airguns in an array
is highly influential on overall sound energy output, because the
output increases approximately linearly with the number of airgun
elements. In this case, because the same air volume is used to operate
two very large guns, rather than tens of smaller guns, the array
produces lower sound levels than a conventional array of equivalent
total volume.
The modeled distances described in the aforementioned Jasco report
show expected per-pulse sound pressure level threshold distances to the
160-dB level of 4.29 kilometers (km). When frequency-weighted, i.e.,
considering the low frequency output of the source relative to the
hearing sensitivities of different marine mammal hearing groups, the
estimated distance is decreased to approximately 1 km for the low-
frequency cetacean hearing group and to de minimis levels for mid- and
high-frequency cetacean hearing groups, significantly less than
comparable modeled distances for the proxy 72-element, 8,000 in\3\
array evaluated in the rule.
These factors lead to a conclusion that take by Level B harassment
associated with use of the Gemini source would be less than would occur
for a similar survey instead using the modeled airgun array as a sound
source. Based on the foregoing, we have determined there will be no
effects of a magnitude or intensity different from those evaluated in
support of the rule. Moreover, use of modeling results relating to use
of the 72 element, 8,000 in\3\ airgun array are expected to be
significantly conservative as a proxy for use in evaluating potential
impacts of use of the Gemini source.
Consistent with the preamble to the final rule, the survey effort
proposed by WesternGeco in its LOA request was used to develop LOA-
specific take estimates based on the acoustic exposure modeling results
described in the preamble (86 FR 5398, January 19, 2021). In order to
generate the appropriate take numbers for authorization, the following
information was considered: (1) survey type; (2) location (by modeling
zone \1\); (3) number of days; and (4) season.\2\ The acoustic exposure
modeling performed in support of the rule provides 24-hour exposure
estimates for each species, specific to each modeled survey type in
each zone and season.
---------------------------------------------------------------------------
\1\ For purposes of acoustic exposure modeling, the GOM was
divided into seven zones. Zone 1 is not included in the geographic
scope of the rule.
\2\ For purposes of acoustic exposure modeling, seasons include
winter (December-March) and summer (April-November).
---------------------------------------------------------------------------
No 3D OBN surveys were included in the modeled survey types, and
use of existing proxies (i.e., two-dimensional (2D), 3D narrow-azimuth
(NAZ), 3D wide-azimuth (WAZ), Coil) is generally conservative for use
in evaluation of 3D OBN survey effort, largely due to the greater area
covered by the modeled proxies. Summary descriptions of these modeled
survey geometries are available in the preamble to the proposed rule
(83 FR 29220, June 22, 2018). Coil was selected as the best available
proxy survey type in this case because the spatial coverage of the
planned survey is most similar to the coil survey pattern.
The planned 3D OBN survey will involve two source vessels sailing
along survey lines averaging 83 km in length. The coil survey pattern
was assumed to cover approximately 144 kilometers squared (km\2\) per
day (compared with approximately 795 km\2\, 199 km\2\, and 845 km\2\
per day for the 2D, 3D NAZ, and 3D WAZ survey patterns, respectively).
Among the different parameters of the modeled survey patterns (e.g.,
area covered, line spacing, number of sources, shot interval, total
simulated pulses), NMFS considers area covered per day to be most
influential on daily modeled exposures exceeding Level B harassment
criteria. Although WesternGeco is not proposing to perform a survey
using the coil geometry, its planned 3D OBN survey is expected to cover
approximately 99.6 km\2\ per day, meaning that the coil proxy is most
representative of the effort planned by WesternGeco in terms of
predicted Level B harassment exposures. In addition, all available
acoustic exposure modeling results assume use of a 72-element, 8,000
in\3\ array. Thus, as discussed above, estimated take numbers for this
LOA are considered conservative due to differences between the acoustic
source planned for use (Gemini or 28 element, 5,240 in\3\ airgun array)
and the proxy array modeled for the rule.
The survey will take place over approximately 85 days, including 65
days of sound source operation. The survey plan includes approximately
half the days within Zone 5 and half the days within Zone 7. We modeled
33 days in each zone for take estimates. The seasonal distribution of
survey days is not known in advance. Therefore, the take estimates for
each species are based on the season that produces the greater value.
For some species, take estimates based solely on the modeling
yielded results that are not realistically likely to occur when
considered in light of other relevant information available during the
rulemaking process regarding marine mammal occurrence in the GOM. The
approach used in the acoustic exposure modeling, in which seven
modeling zones were defined over the U.S. GOM, necessarily averages
fine-scale information about marine mammal distribution over the large
area of each
[[Page 72741]]
modeling zone. This can result in unrealistic projections regarding the
likelihood of encountering particularly rare species and/or species not
expected to occur outside particular habitats. Thus, although the
modeling conducted for the rule is a natural starting point for
estimating take, our rule acknowledged that other information could be
considered (e.g., 86 FR 5322, January 19, 2021), discussing the need to
provide flexibility and make efficient use of previous public and
agency review of other information and identifying that additional
public review is not necessary unless the model or inputs used differ
substantively from those that were previously reviewed by NMFS and the
public). For this survey, NMFS has other relevant information reviewed
during the rulemaking that indicates use of the acoustic exposure
modeling to generate a take estimate for Rice's whales and killer
whales produces results inconsistent with what is known regarding their
occurrence in the GOM. Accordingly, we have adjusted the calculated
take estimates for those species as described below.
NMFS' final rule described a ``core habitat area'' for Rice's
whales (formerly known as GOM Bryde's whales) \3\ located in the
northeastern GOM in waters between 100 and 400 m depth along the
continental shelf break (Rosel et al., 2016). However, whaling records
suggest that Rice's whales historically had a broader distribution
within similar habitat parameters throughout the GOM (Reeves et al.,
2011; Rosel and Wilcox, 2014). In addition, habitat-based density
modeling identified similar habitat (i.e., approximately 100-400 m
water depths along the continental shelf break) as being potential
Rice's whale habitat (Roberts et al., 2016), although the core habitat
area contained approximately 92 percent of the predicted abundance of
Rice's whales. See discussion provided at, e.g., 83 FR 29228, June 22,
2018; 83 FR 29280, June 22, 2018; 86 FR 5418, January 19, 2021.
---------------------------------------------------------------------------
\3\ The final rule refers to the GOM Bryde's whale (Balaenoptera
edeni). These whales were subsequently described as a new species,
Rice's whale (Balaenoptera ricei) (Rosel et al., 2021).
---------------------------------------------------------------------------
Although Rice's whales may occur outside of the core habitat area,
we expect that any such occurrence would be limited to the narrow band
of suitable habitat described above (i.e., 100-400 m) and that, based
on the few available records, these occurrences would be rare.
WesternGeco's planned activities will occur in water depths of
approximately 1,000-3,000 m in the central GOM. Thus, NMFS does not
expect there to be the reasonable potential for take of Rice's whale in
association with this survey and, accordingly, does not authorize take
of Rice's whale through the LOA.
Killer whales are the most rarely encountered species in the GOM,
typically in deep waters of the central GOM (Roberts et al., 2015;
Maze-Foley and Mullin, 2006). As discussed in the final rule, the
density models produced by Roberts et al. (2016) provide the best
available scientific information regarding predicted density patterns
of cetaceans in the U.S. GOM. The predictions represent the output of
models derived from multi-year observations and associated
environmental parameters that incorporate corrections for detection
bias. However, in the case of killer whales, the model is informed by
few data, as indicated by the coefficient of variation associated with
the abundance predicted by the model (0.41, the second-highest of any
GOM species model; Roberts et al., 2016). The model's authors noted the
expected non-uniform distribution of this rarely-encountered species
(as discussed above) and expressed that, due to the limited data
available to inform the model, it ``should be viewed cautiously''
(Roberts et al., 2015). NOAA surveys in the GOM from 1992 to 2009
reported only 16 sightings of killer whales, with an additional 3
encounters during more recent survey effort from 2017 to 2018 (Waring
et al., 2013; <a href="https://www.boem.gov/gommapps">https://www.boem.gov/gommapps</a>). Two other species were
also observed on fewer than 20 occasions during the 1992-2009 NOAA
surveys (Fraser's dolphin and false killer whale \4\). However,
observational data collected by protected species observers (PSO) on
industry geophysical survey vessels from 2002 to 2015 distinguish the
killer whale in terms of rarity. During this period, killer whales were
encountered on only 10 occasions, whereas the next most rarely
encountered species.\4\ However, note that these species have been
observed over a greater range of water depths in the GOM than have
killer whales. (Fraser's dolphin) was recorded on 69 occasions
(Barkaszi and Kelly, 2019). The false killer whale and pygmy killer
whale were the next most rarely encountered species, with 110 records
each. The killer whale was the species with the lowest detection
frequency during each period over which PSO data were synthesized
(2002-2008 and 2009-2015). This information qualitatively informed our
rulemaking process, as discussed at 86 FR 5322 and 86 FR 5334 (January
19, 2021), and similarly informs our analysis here.
---------------------------------------------------------------------------
\4\ However, note that these species have been observed over a
greater range of water depths in the GOM than have killer whales.
---------------------------------------------------------------------------
The rarity of encounter during seismic surveys is not likely to be
the product of high bias on the probability of detection. Unlike
certain cryptic species with high detection bias, such as Kogia spp. or
beaked whales, or deep-diving species with high availability bias, such
as beaked whales or sperm whales, killer whales are typically available
for detection when present and are easily observed. Roberts et al.
(2015) stated that availability is not a major factor affecting
detectability of killer whales from shipboard surveys, as they are not
a particularly long-diving species. Baird et al. (2005) reported that
mean dive durations for 41 fish-eating killer whales for dives greater
than or equal to 1 minute in duration was 2.3-2.4 minutes, and Hooker
et al. (2012) reported that killer whales spent 78 percent of their
time at depths between 0 and 10 m. Similarly, Kvadsheim et al. (2012)
reported data from a study of 4 killer whales, noting that the whales
performed 20 times as many dives 1-30 m in depth than to deeper waters,
with an average depth during those most common dives of approximately 3
m.
In summary, killer whales are the most rarely encountered species
in the GOM and typically occur only in particularly deep water. This
survey would take place in deep waters that would overlap with depths
in which killer whales typically occur. While this information is
reflected through the density model informing the acoustic exposure
modeling results, there is relatively high uncertainty associated with
the model for this species, and the acoustic exposure modeling applies
mean distribution data over areas where the species is in fact less
likely to occur. In addition, as noted above in relation to the general
take estimation methodology, the assumed proxy source (72-element,
8,000-in\3\ array) results in a significant overestimate of the actual
potential for take to occur. NMFS' determination in reflection of the
information discussed above, which informed the final rule, is that use
of the generic acoustic exposure modeling results for killer whales
will generally result in estimated take numbers that are inconsistent
with the assumptions made in the rule regarding expected killer whale
take (86 FR 5322, January 19, 2021; 86 FR 5403, January 19, 2021).
In past authorizations, NMFS has often addressed situations
involving the low likelihood of encountering a rare species such as
killer whales in the
[[Page 72742]]
GOM through authorization of take of a single group of average size
(i.e., representing a single potential encounter). See 83 FR 63268,
December 7, 2018; 86 FR 29090, May 28, 2021; 85 FR 55645, September 9,
2020. For the reasons expressed above, NMFS determined that a single
encounter of killer whales is more likely than the model-generated
estimates and has authorized take associated with a single group
encounter (i.e., up to seven animals for killer whales).
Based on the results of our analysis, NMFS has determined that the
level of taking authorized through the LOA is consistent with the
findings made for the total taking allowable under the regulations for
the affected species or stocks of marine mammals. See Table 1 in this
notice and Table 9 of the rule (86 FR 5322, January 19, 2021).
Small Numbers Determination
Under the GOM rule, NMFS may not authorize incidental take of
marine mammals in an LOA if it will exceed ``small numbers.'' In short,
when an acceptable estimate of the individual marine mammals taken is
available, if the estimated number of individual animals taken is up
to, but not greater than, one-third of the best available abundance
estimate, NMFS will determine that the numbers of marine mammals taken
of a species or stock are small. For more information please see NMFS'
discussion of the MMPA's small numbers requirement provided in the
final rule (86 FR 5438, January 19, 2021).
The take numbers for authorization are determined as described
above in the Summary of Request and Analysis section. Subsequently, the
total incidents of harassment for each species are multiplied by scalar
ratios to produce a derived product that better reflects the number of
individuals likely to be taken within a survey (as compared to the
total number of instances of take), accounting for the likelihood that
some individual marine mammals may be taken on more than 1 day (see 86
FR 5404, January 19, 2021). The output of this scaling, where
appropriate, is incorporated into adjusted total take estimates that
are the basis for NMFS' small numbers determinations, as depicted in
Table 1.
This product is used by NMFS in making the necessary small numbers
determinations through comparison with the best available abundance
estimates (see discussion at 86 FR 5322, January 19, 2021; 86 FR 5391,
January 19, 2021). For this comparison, NMFS' approach is to use the
maximum theoretical population, determined through review of current
stock assessment reports (SAR; <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-species-stock">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-species-stock</a>) and model-predicted abundance information (<a href="https://seamap.env.duke.edu/models/Duke/GOM/">https://seamap.env.duke.edu/models/Duke/GOM/</a>). For the latter, for taxa where a
density surface model could be produced, we use the maximum mean
seasonal (i.e., 3-month) abundance prediction for purposes of
comparison as a precautionary smoothing of month-to-month fluctuations
and in consideration of a corresponding lack of data in the literature
regarding seasonal distribution of marine mammals in the GOM.
Information supporting the small numbers determinations is provided in
Table 1.
Table 1--Take Analysis
----------------------------------------------------------------------------------------------------------------
Authorized Scaled take Percent
Species take \1\ Abundance \2\ abundance
----------------------------------------------------------------------------------------------------------------
Rice's whale.................................... 0 n/a 51 n/a
Sperm whale..................................... 1,043 441 2,207 20.0
Kogia spp....................................... \3\ 426 129 4,373 3.5
Beaked whales................................... 5,374 543 3,768 14.4
Rough-toothed dolphin........................... 946 271 4,853 5.6
Bottlenose dolphin.............................. 3,129 898 176,108 0.5
Clymene dolphin................................. 2,611 749 11,895 6.3
Atlantic spotted dolphin........................ 1,247 358 74,785 0.5
Pantropical spotted dolphin..................... 15,927 4,571 102,361 4.5
Spinner dolphin................................. 2,430 697 25,114 2.8
Striped dolphin................................. 1,117 321 5,229 6.1
Fraser's dolphin................................ 332 95 1,665 5.7
Risso's dolphin................................. 667 197 3,764 5.2
Melon-headed whale.............................. 1,706 503 7,003 7.2
Pygmy killer whale.............................. 524 155 2,126 7.3
False killer whale.............................. 725 214 3,204 6.7
Killer whale.................................... 7 n/a 267 2.6
Short-finned pilot whale........................ 391 115 1,981 5.8
----------------------------------------------------------------------------------------------------------------
\1\ Scalar ratios were applied to ``Authorized Take'' values as described at 86 FR 5322 and 86 FR 5404 (January
19, 2021) to derive scaled take numbers shown here.
\2\ Best abundance estimate. For most taxa, the best abundance estimate for purposes of comparison with take
estimates is considered here to be the model-predicted abundance (Roberts et al., 2016). For those taxa where
a density surface model predicting abundance by month was produced, the maximum mean seasonal abundance was
used. For those taxa where abundance is not predicted by month, only mean annual abundance is available. For
Rice's whale and the killer whale, the larger estimated SAR abundance estimate is used.
\3\ Includes 26 takes by Level A harassment and 400 takes by Level B harassment. Scalar ratio is applied to
takes by Level B harassment only; small numbers determination made on basis of scaled Level B harassment take
plus authorized Level A harassment take.
Based on the analysis contained herein of WesternGeco's proposed
survey activity described in its LOA application and the anticipated
take of marine mammals, NMFS finds that small numbers of marine mammals
will be taken relative to the affected species or stock sizes (i.e.,
less than one-third of the best available abundance estimate) and
therefore the taking is of no more than small numbers.
Authorization
NMFS has determined that the level of taking for this LOA request
is consistent with the findings made for the total taking allowable
under the incidental take regulations and that the amount of take
authorized under the LOA is of no more than small numbers. Accordingly,
we have issued an LOA to WesternGeco authorizing the take of
[[Page 72743]]
marine mammals incidental to its geophysical survey activity, as
described above.
Dated: October 17, 2023.
Kim Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2023-23298 Filed 10-20-23; 8:45 am]
BILLING CODE 3510-22-P
</pre></body>
</html>Indexed from Federal Register on October 23, 2023.
This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.