Final 2023 Marine Mammal Stock Assessment Reports

<NOTICE> DEPARTMENT OF COMMERCE <SUBAGY>National Oceanic and Atmospheric Administration</SUBAGY> <DEPDOC>[RTID 0648-XE168]</DEPDOC> <SUBJECT>Final 2023 Marine Mammal Stock Assessment Reports</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. <HD SOURCE="HED">ACTION:</HD> Notice; response to comments. <SUM> <HD SOURCE="HED">SUMMARY:</HD> As required by the Marine Mammal Protection Act (MMPA), NMFS has considered public comments for revisions of the 2023 marine mammal stock assessment reports (SARs). This notice announces the availability of 66 final 2023 SARs that were updated and finalized. </SUM> <HD SOURCE="HED">ADDRESSES:</HD> The 2023 final SARs are available in electronic form via the internet at <E T="03">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments</E> <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Zachary Schakner, Office of Science and Technology, 301-427-8106, <E T="03">Zachary.Schakner@noaa.gov</E> ; Nancy Young, 206-526-4297, <E T="03">Nancy.Young@noaa.gov,</E> regarding Alaska regional stock assessments; Jessica McCordic, 508-495-2396, <E T="03">Jessica.McCordic@noaa.gov,</E> regarding Atlantic, Gulf of Mexico, and Caribbean regional stock assessments; or Jim Carretta, 858-546-7171, <E T="03">Jim.Carretta@noaa.gov,</E> regarding Pacific regional stock assessments. </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Background</HD> Section 117 of the MMPA (16 U.S.C. 1361 <E T="03">et seq.</E> ) requires NMFS and the U.S. Fish and Wildlife Service (USFWS) to prepare stock assessments for each stock of marine mammals occurring in waters under the jurisdiction of the United States, including the U.S. Exclusive Economic Zone (EEZ). These SARs must contain information regarding the distribution and abundance of the stock, population growth rates and trends, estimates of annual human-caused mortality and serious injury (M/SI) from all sources, descriptions of the fisheries with which the stock interacts, and the status of the stock. Initial SARs were completed in 1995. The MMPA requires NMFS and USFWS to review the SARs at least annually for strategic stocks and stocks for which significant new information is available and at least once every three years for non-strategic stocks. The term “strategic stock” means a marine mammal stock: (A) for which the level of direct human-caused mortality exceeds the potential biological removal level or PBR (defined by the MMPA as the maximum number of animals, not including natural mortalities, that may be removed from a marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population); (B) which, based on the best available scientific information, is declining and is likely to be listed as a threatened species under the Endangered Species Act (ESA) within the foreseeable future; or (C) which is listed as a threatened species or endangered species under the ESA or is designated as depleted under the MMPA. NMFS and USFWS are required to revise a SAR if they determine the review indicates that the status of the stock has changed or can be more accurately determined. In order to ensure that marine mammal SARs constitute the best scientific information available, the updated SARs under NMFS' jurisdiction are peer-reviewed within NMFS Science Centers and by members of three regional independent scientific review groups established under the MMPA to independently advise NMFS and the USFWS on marine mammals. As a result of the time involved in the assessment of new scientific information, revision, and peer-review of the SARs, the period covered by the 2023 final SARs is generally 2017 through 2021. NMFS reviewed the status of all marine mammal strategic stocks and considered whether significant new information was available for all other stocks under NMFS' jurisdiction. As a result of this review, NMFS revised or developed new reports for 66 stocks in the Alaska, Atlantic, and Pacific regions to incorporate new information. The 2023 revisions to the SARs consist primarily of updated or revised human-caused M/SI estimates and updated abundance estimates. This publication also finalizes (1) a new SAR for a newly described species, Sato's beaked whale (2) revisions to the stock structure of West Coast harbor porpoise that splits the Northern California-Southern Oregon stock into two stocks (the Northern California-Southern Oregon stock and the Central Oregon stock) and (3) name changes for all stocks with '4-Islands' in the name to 'Maui Nui' to align with the original Hawaiian names of various islands and places where the stocks reside. The 2023 revisions to the abundance and trend sections of the main Hawaiian Islands insular false killer whale section of the false killer whale SAR are not being finalized at this time because of a delay in the publication of updated abundance estimates. The mortality and serious injury information has been updated together with the other false killer whale stocks represented in this SAR. The abundance and trend sections for main Hawaiian Islands insular false killer whales will be revised in a subsequent SAR cycle. The draft 2023 SAR for the Washington Inland Waters harbor seal stocks is not being finalized at this time given that the draft Pearson <E T="03">et al.</E> estimates of abundance and trends remain unpublished. This SAR will be revised in a subsequent cycle when the abundance estimates for these stocks are published. NMFS received comments on the draft 2023 SARs from the Marine Mammal Commission (Commission); the Department of Fisheries and Oceans Canada (DFO); two fishing industry associations (Hawaii Longline Association (HLA) and Maine Lobstermen's Association (MLA)); an environmental non-governmental organization (Center for Biological Diversity); two Alaska Natives Organizations (Chugach Regional Resources Commission and the Aleut Community of St. Paul Island); and the Western Pacific Regional Fishery Management Council (Council). Our responses to substantive comments are below. We have not responded to comments that failed to raise a significant point for us to consider ( <E T="03">e.g.,</E> comments that are out of scope of the draft SARs). We appreciate the Commission's program-level comments and will take them into consideration, as appropriate, in the future. In response to a comment from MLA that noted NMFS relied on an incorrect population size estimate for the NARW SAR, we have further revised the NARW SAR to include the latest and best available estimate on NARW abundance, which also now incorporates an improvement to the underlying model to allow for the potential of recruitment based on observed calves (Linden 2024a,b). However, we note that the issue of having multiple abundance estimates for the NARW population using the same general model is not new. It is an outcome of the timing of the SAR cycle and when the data are available to perform an updated model run. Since 2017, NMFS has produced annual NARW population size estimates in collaboration with the New England Aquarium, which are released at the North Atlantic Right Whale Consortium's annual meeting, typically in October each year. In 2023, NMFS began publishing these estimates in stand-alone peer-reviewed Technical Memorandum to provide full and transparent documentation of the estimation process and results ( <E T="03">e.g.,</E> Linden 2023, Linden 2024b). However, the timing of the release of these estimates has not allowed for their straightforward incorporation into the contemporaneous final NARW SAR. This is, in part, because NMFS' marine mammal SARs are typically reviewed by the SRGs in early spring, subsequently made available for public comment, and then finalized with a notice in the <E T="04">Federal Register</E> . Abundance estimates produced in October are, therefore, not typically available for inclusion in the latest SAR before SRG review and public comment. Nevertheless, NMFS agrees with MLA that the NARW abundance estimates produced each October should generally be considered the best available scientific information on the population size of NARWs for that year, as long as all necessary review requirements, including peer review, have been satisfied. Furthermore, NMFS recognizes that having multiple abundance estimates for the NARW population publicly available in various stages of the SAR process, including multiple estimates for any given single year, creates confusion and ambiguity as to what is the best available and most recent estimate of the population size. To address this timing issue for the final 2023 SAR and minimize similar timing issues going forward, NMFS is modifying certain procedural steps in developing the NARW SAR. Specifically, the final 2023 NARW SAR has been updated to include the latest abundance estimate published in Linden (2024b) in October 2024, along with the most recent human-caused mortality and serious injury data based on Henry <E T="03">et al.</E> 2024. In future SAR cycles, NMFS anticipates it will proceed similarly to include the most recent data available in the most recent NARW SAR when finalized. A key aspect of the NARW stock assessment process that allows for NMFS to incorporate the best available science into the final SAR is that unless the model used to estimate population abundance is significantly modified, additional runs of the model to produce newer estimates only necessitate a Level 1 review per NMFS' <E T="03">Guidelines for Preparing Stock Assessment Reports Pursuant to the Marine Mammal Protection Act</E> (NMFS 2023, hereafter the GAMMS). Per the GAMMS section 3.6 Ensuring Appropriate Peer Review of New Information peer review, Le ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 55k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━