```

[Federal Register Volume 90, Number 12 (Tuesday, January 21, 2025)]
[Notices]
[Pages 7102-7104]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-01369]

[[Page 7102]]

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

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XE554]

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 of 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 NMFS has issued a Letter of Authorization (LOA) to bp Exploration 
and Production, Inc., (bp) for the take of marine mammals incidental to 
geophysical survey activity in the Gulf of Mexico (GOM).

DATES: The LOA is effective from January 14, 2025, through December 31, 
2025.

ADDRESSES: The LOA, LOA request, and supporting documentation are 
available online at: https://www.fisheries.noaa.gov/action/incidental-take-authorization-oil-and-gas-industry-geophysical-survey-activity-gulf-mexico. In case of problems accessing these documents, please call 
the contact listed below (see FOR FURTHER INFORMATION CONTACT section).

FOR FURTHER INFORMATION CONTACT: Ben Laws, 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 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, and became effective on April 19, 2021.
    The 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 50 CFR 
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 authorized under the LOA is of no more than small 
numbers.
    NMFS subsequently discovered that the 2021 rule was based on 
erroneous take estimates. We conducted another rulemaking using correct 
take estimates and other newly available and pertinent information 
relevant to the analyses supporting some of the findings in the 2021 
final rule and the taking allowable under the regulations. We issued a 
final rule in April 2024, effective May 24, 2024 (89 FR 31488, April 
24, 2024).
    The 2024 final rule made no changes to the specified activities or 
the specified geographical region in which those activities would be 
conducted, nor to the original 5-year period of effectiveness. In 
consideration of the new information, the 2024 rule presented new 
analyses supporting affirmance of the negligible impact determinations 
for all species, and affirmed that the existing regulations, which 
contain mitigation, monitoring, and reporting requirements, are 
consistent with the ``least practicable adverse impact'' standard of 
the MMPA.

Summary of Request and Analysis

    Bp plans to conduct a field trial of a marine vibrator source (C-
BASS) array in the Atlantis prospect area centered around Green Canyon 
block 743 for a duration of up to 14 days, with water depths ranging 
from approximately 1,300 to 2,200 m. See figure 1 of the LOA 
application for a map of the area.
    The marine vibrator 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 (see 86 FR 
5322, 5442, January 19, 2021).
    Marine vibrator sources represent an alternative to traditional 
airgun sources, and operate by displacing a volume of water with a 
vibrating plate or shell to create a pressure wave. In contrast to 
airgun sources, marine vibrators produce a long duration, low amplitude 
signal and operate at a lower peak intensity. The C-BASS source 
consists of two types of sweep units: six M72-15 and two M72-30, 
comprising eight total source units mounted on a tow body. Both sets of 
units (M72-15 and M72-30) will sweep for 8 seconds (s), with the two 
signals overlapping. The M72-30 signal will lag the M72-15 by 0.5 s. 
The total sweep cycle will be repeated every 16 s with a 7.5 s quiet 
period in between sweeps. The dominant frequencies of the C-BASS sweep 
are between 10-50 Hz, with minimal signal energy occurring above

[[Page 7103]]

100 Hz. Marine vibrator sources, including the C-BASS, produce signals 
with a relatively gentle rise and decay over time and are therefore 
considered to be non-impulsive. The usage characteristics described 
above, which equate to a duty cycle of 53 percent and allow for periods 
of silence between each signal, result in evaluation of the C-BASS as 
an intermittent source for purposes of the planned trial. Please see 
bp's application for additional detail.
    Use of a relatively low-intensity, non-impulsive source such as the 
C-BASS is likely to result in significantly less take by Level B 
harassment than would occur for a similar survey using an airgun array 
as a sound source, and use of the C-BASS source is unlikely to result 
in any potential for Level A harassment. In order to demonstrate this, 
bp provided an exposure modeling report in association with its LOA 
application. The exposure modeling effort was performed using the same 
modeling approach as was used in support of the 2021 and 2024 rules. 
Modeling of the C-BASS source compared with the same 5,110 cubic inch 
(in\3\) airgun array used for additional exposure modeling for the 2024 
rule illustrates a reduction in estimated Level B harassment distance 
of over 98 percent, with acoustic exposures above harassment criteria 
associated with use of the C-BASS source generally less than 1 percent 
those associated with use of the airgun array. Please bp's exposure 
modeling report for more detail.
    Based on this information we have determined there will be no 
effects of a magnitude or intensity different from those evaluated in 
support of the rules. NMFS therefore expects that use of modeling 
results supporting the final rule are conservative as a proxy for use 
in evaluating potential impacts of use of the marine vibrator source.
    We also note that for the marine vibrator source, the Bureau of 
Ocean Energy Management (BOEM) determined that Endangered Species Act 
(ESA) section 7 step-down review was required under NMFS' 2020 
Biological Opinion on Federally Regulated Oil and Gas Program 
Activities in the Gulf of Mexico. NMFS' ESA Interagency Consultation 
Division requested and received an analysis from BOEM that considered 
the effects associated with the source. As a result of this review, 
NMFS determined that use of the source is unlikely to result in 
additional effects beyond those previously considered in the 2020 
Biological Opinion.
    The survey effort proposed by bp in its LOA request was used to 
develop LOA-specific take estimates based on the acoustic exposure 
modeling results described in our rule preamble (89 FR 31488, April 24, 
2024). In order to generate the appropriate take number for 
authorization, the following information was considered: (1) survey 
type; (2) location (by modeling zone \1\); (3) number of days; (4) 
source; and (5) month.\2\ In this case, the 4,130 in\3\ airgun array 
was selected, as its use for purposes of generating take numbers for 
authorization represents the least impactful airgun array (but remains 
conservative for use in estimating takes that are expected to result 
from use of the C-BASS source, as discussed above). The acoustic 
exposure modeling performed in support of the rule provides 24-hour 
exposure estimates for each species, specific to each modeled source 
and survey type in each zone and month.
---------------------------------------------------------------------------

    \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\ Acoustic propagation modeling was performed for two seasons: 
winter (December-March) and summer (April-November). Marine mammal 
density data is generally available on a monthly basis, and 
therefore further refines take estimates temporally.
---------------------------------------------------------------------------

    Summary descriptions of modeled survey geometries are available in 
the preamble to the 2018 proposed rule (83 FR 29212, 29220, June 22, 
2018). Coil was selected as the best available proxy survey type in 
this case because this selection minimizes over-estimation of take. 
Although bp is not proposing to perform a survey using the coil 
geometry, the coil proxy is most representative of the effort planned 
by bp in terms of predicted Level B harassment exposures.
    The survey will include up to 14 days of sound source operation in 
zones 5 and 7. We assume equal distribution of survey effort over the 
two zones. Although the survey is currently planned to occur in March 
2025, the actual timing is not known in advance, so take estimates for 
each species are based on the time period that produces the greatest 
value.
    Based on the results of our analysis, NMFS has determined that the 
level of taking expected for this survey and authorized through the LOA 
is consistent with the findings made for the total taking allowable 
under the regulations. See table 1 in this notice and table 6 of the 
2024 final rule (89 FR 31488, April 24, 2024).

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 (89 FR 31535, April 24, 2024). For more 
information please see NMFS' discussion of small numbers in the 2021 
final rule (86 FR 5438, January 19, 2021).
    The take numbers for authorization, determined as described above 
in the Summary of Request and Analysis section, are used by NMFS in 
making the necessary small numbers determinations, through comparison 
with the best available abundance estimates (see discussion at 86 FR 
5322, 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; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and 
model-predicted abundance information (https://seamap.env.duke.edu/models/Duke/GOM/). Information supporting the small numbers 
determinations is provided in table 1.

                                           Table 1--Take Analysis \1\
----------------------------------------------------------------------------------------------------------------
                                                                    Authorized                        Percent
                             Species                                   take        Abundance \2\     abundance
----------------------------------------------------------------------------------------------------------------
Rice's whale....................................................               0              51             n/a
Sperm whale.....................................................             102           3,007             3.4
Kogia spp.......................................................          \3\ 50             980             5.1
Beaked whales...................................................             248             803            30.9
Rough-toothed dolphin...........................................             254           4,853             5.2

[[Page 7104]]

 
Bottlenose dolphin..............................................             210         165,125             0.1
Clymene dolphin.................................................             308           4,619             6.7
Atlantic spotted dolphin........................................              62          21,506             0.3
Pantropical spotted dolphin.....................................           2,989          67,225             4.4
Spinner dolphin.................................................         \4\ 152           5,548             2.7
Striped dolphin.................................................             892           5,634            15.8
Fraser's dolphin................................................             102           1,665             6.1
Risso's dolphin.................................................              73           1,974             3.7
Blackfish \5\...................................................             704           6,113            11.5
Short-finned pilot whale........................................              82           2,741             3.0
----------------------------------------------------------------------------------------------------------------
\1\ Scalar ratios were not applied in this case due to brief survey duration.
\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 (Garrison et al., 2023). For Rice's whale,
  Atlantic spotted dolphin, and Risso's dolphin, the larger estimated SAR abundance estimate is used.
\3\ Estimated takes include 3 takes by Level A harassment and 47 takes by Level B harassment. However, as the
  actual source planned for use is a non-impulsive source, no take by Level A harassment is likely to occur and
  all authorized takes are by Level B harassment.
\4\ Modeled take of 53 increased to account for potential encounter with a group of average size (Maze-Foley and
  Mullin, 2006).
\5\ The ``blackfish'' guild includes melon-headed whales, false killer whales, pygmy killer whales, and killer
  whales.

    Based on the analysis contained herein of bp'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 bp authorizing the take of marine mammals 
incidental to its geophysical survey activity, as described above.

    Dated: January 15, 2025.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2025-01369 Filed 1-17-25; 8:45 am]
BILLING CODE 3510-22-P
```