Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to a Marine Geophysical Survey of the East Pacific Rise in the Eastern Tropical Pacific Ocean

<NOTICE> DEPARTMENT OF COMMERCE <SUBAGY>National Oceanic and Atmospheric Administration</SUBAGY> <DEPDOC>[RTID 0648-XF213]</DEPDOC> <SUBJECT>Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to a Marine Geophysical Survey of the East Pacific Rise in the Eastern Tropical Pacific Ocean</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. <HD SOURCE="HED">ACTION:</HD> Notice; proposed incidental harassment authorization; request for comments on proposed authorization and possible renewal. <SUM> <HD SOURCE="HED">SUMMARY:</HD> NMFS has received a request from the Lamont-Doherty Earth Observatory (L-DEO) for authorization to take marine mammals incidental to a marine geophysical survey of the East Pacific Rise in the Eastern Tropical Pacific Ocean (ETP). Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue an incidental harassment authorization (IHA) to incidentally take marine mammals during the specified activities. NMFS is also requesting comments on a possible one-time, 1-year renewal that could be issued under certain circumstances and if all requirements are met, as described in Request for Public Comments at the end of this notice. NMFS will consider public comments prior to making any final decision on the issuance of the requested MMPA authorization and agency responses will be summarized in the final notice of our decision. </SUM> <DATES> <HD SOURCE="HED">DATES:</HD> Comments and information must be received no later than January 20, 2026. </DATES> <HD SOURCE="HED">ADDRESSES:</HD> Comments should be addressed to the Permits and Conservation Division, Office of Protected Resources, National Marine Fisheries Service and should be submitted via email to <E T="03">ITP.harlacher@noaa.gov.</E> Electronic copies of the application and supporting documents, as well as a list of the references cited in this document, may be obtained online at: <E T="03">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-research-and-other-activities.</E> In case of problems accessing these documents, please call the contact listed below. <E T="03">Instructions:</E> NMFS is not responsible for comments sent by any other method, to any other address or individual, or received after the end of the comment period. Comments, including all attachments, must not exceed a 25-megabyte file size. All comments received are a part of the public record and will generally be posted online at <E T="03">https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act</E> without change. All personal identifying information ( <E T="03">e.g.,</E> name, address) voluntarily submitted by the commenter may be publicly accessible. Do not submit confidential business information or otherwise sensitive or protected information. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Jenna Harlacher, Office of Protected Resources, NMFS, (301) 427-8401. </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Background</HD> The MMPA prohibits the “take” of marine mammals, with certain exceptions. Section 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 <E T="03">et seq.</E> ) directs the Secretary of Commerce (as delegated to NMFS) 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 proposed or, if the taking is limited to harassment, a notice of a proposed IHA is provided to the public for review. Authorization for incidental takings 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 taking for subsistence uses (where relevant). Further, NMFS must prescribe the permissible methods of taking; other “means of effecting the least practicable adverse impact” on the affected species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, and on the availability of the species or stocks for taking for certain subsistence uses (referred to as “mitigation”); and requirements pertaining to the monitoring and reporting of the takings. The definitions of all applicable MMPA statutory terms used above are included in the relevant sections below ( <E T="03">see also</E> 16 U.S.C. 1362; 50 C.F.R 216.3, 216.103). <HD SOURCE="HD1">National Environmental Policy Act</HD> To comply with the National Environmental Policy Act of 1969 (NEPA; 42 U.S.C. 4321 <E T="03">et seq.</E> ) and NOAA Administrative Order (NAO) 216-6A, NMFS must review our proposed action ( <E T="03">i.e.,</E> the issuance of an IHA) with respect to potential impacts on the human environment. This action is consistent with categories of activities identified in Categorical Exclusion B4 (IHAs with no anticipated serious injury or mortality) of the Companion Manual for NAO 216-6A, which do not individually or cumulatively have the potential for significant impacts on the quality of the human environment and for which we have not identified any extraordinary circumstances that would preclude this categorical exclusion. Accordingly, NMFS has preliminarily determined that the issuance of the proposed IHA qualifies to be categorically excluded from further NEPA review. <HD SOURCE="HD1">Summary of Request</HD> On June 16, 2025, NMFS received a request from L-DEO for an IHA to take marine mammals incidental to a marine geophysical survey of the East Pacific Rise in the ETP. After review of the application and confirming details with the applicant, the application was deemed adequate and complete on September 10, 2025. L-DEO's request is for take of 28 species of marine mammals, by Level B harassment only. Neither L-DEO nor NMFS expect serious injury or mortality to result from this activity and, therefore, an IHA is appropriate. <HD SOURCE="HD1">Description of Proposed Activity</HD> <HD SOURCE="HD2">Overview</HD> Researchers from the University of California, San Diego, and Woods Hole Oceanographic Institution, with funding from the National Science Foundation (NSF), and in collaboration with the Institut de Physique du Globe de Paris, propose to conduct a three-dimensional (3-D) seismic survey, using airguns as the acoustic source, from the research vessel (R/V) <E T="03">Marcus G. Langseth</E> ( <E T="03">Langseth</E> ), which is owned and operated by L-DEO. The proposed survey would occur off Western Mexico in the ETP from approximately February 2026 to March 2026. The proposed survey would occur within international waters, in water depths ranging from approximately 2,500 to 3,200 meters (m). To complete this 3-D survey, the <E T="03">Langseth</E> would tow 2 18-airgun arrays with a total discharge volume of approximately 3,300 cubic inch (in <SU>3</SU> ) (54,077 cubic centimeters (cc)) each, at a depth of 7.5 m. The airgun array receiver would consist of four 5,850 m long solid-state hydrophone streamer. The airguns would fire at a shot interval of 37.5 m. Approximately 3,110 kilometers (km) of seismic acquisition is planned. Airgun arrays would introduce underwater sound that may result in take of marine mammals. The purpose of the proposed survey is to obtain information that would be used to address the evolution of fast-spreading mid-ocean ridge magmatic systems and volcanic cycles at the East Pacific Rise in the ETP. The main goal of the proposed seismic surveys is to collect 3-D multi-channel seismic (MCS) reflection data in the ETP, repeating the same experiment conducted in 2008 on board <E T="03">Langseth.</E> The two datasets would be processed together, in order to obtain high-resolution imagery that would be used to investigate how the magmatic and hydrothermal plumbing systems beneath this submarine volcanic ridge have changed since 2008, thereby allowing for a unique four-dimensional (4-D) time-lapse study. The time-lapse imagery would allow scientists to test long-debated hypotheses about the eruption cycle for the first time, by distinguishing characteristic changes in the shape and melt content of the magmatic system. <HD SOURCE="HD2">Dates and Duration</HD> The proposed IHA would be valid for the statutory maximum of 1 year from the date of effectiveness. It will become effective upon written notification from the applicant to NMFS, but not beginning later than 1 year from the date of issuance or extending beyond 2 years from the date of issuance. The expected timing of the survey is February through March 2026, lasting 35 days, which includes approximately 20 days of seismic operations, 3.5 days of Ocean Bottom Seismometers deployment, 4 days of equipment deployment/recovery, 6 days contingency, and 5 days of transit. <HD SOURCE="HD2">Specific Geographic Region</HD> The proposed survey would occur within approximately 10.2° N lat., 104.5° W long.; 10.2° N lat., 104.1° W long.; 8.3° N lat., 104.1° W long.; and 8.3° N lat., 104.5° W long., off the Pacific coast of Mexico in international waters, in water depths ranging from approximately 2,500 to 3,200 m. The region where the survey is proposed to occur is depicted in figure 1. Representative survey tracklines are shown; however, some deviation in actual tracklines, including the order of survey operations, could be necessary for reasons such as science drivers, poor data quality, inclement weather, or mechanical issues with the research vessel and/or equipment. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 225k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━