U.S. Pacific marine mammal stock assessments: 2022

Under the 1994 amendments to the Marine Mammal Protection Act (MMPA), the National Marine Fisheries Service (NMFS) and the U.S. Fish and Wildlife Service (USFWS) are required to publish Stock Assessment Reports for all stocks of marine mammals within U.S. waters, to review new information every year for strategic stocks and every three years for non-strategic stocks, and to update the stock assessment reports when significant new information becomes available. Pacific region stock assessments include those studied by the Southwest Fisheries Science Center (SWFSC, La Jolla, CA), the Pacific Islands Fisheries Science Center (PIFSC, Honolulu, HI), the Marine Mammal Laboratory (NMML, Seattle, WA), and the Northwest Fisheries Science Center (NWFSC, Seattle, WA). The 2022 Draft Pacific marine mammal stock assessments include revised reports for 5 Pacific marine mammal stocks und er NMFS jurisdiction, including 4 “strategic” stocks: Hawaiian monk seal, Southern Resident killer whale, and two new humpback whale stocks that summer in U.S. West Coast waters and winter in Central America and Mexico waters. NMFS revised the stock structure for all North Pacific humpback whale stocks. This resulted in five new humpback whale stocks in the North Pacific, two of which are contained within the Pacific SARs: the “Central America / Southern Mexico - CA-OR-WA”, and “Mainland Mexico - CA-OR-WA” humpback whale stocks. New information on abundance is included in all the revised reports, as well as new information on human-caused sources of mortality and serious injury Information on sea otters, manatees, walrus, and polar bears are published separately by the US Fish and Wildlife Service. This is a working document and individual stock assessment reports will be updated as new information on marine mammal stocks and fisheries becomes available. Background information and guidelines for preparing stock assessment reports are reviewed in NOAA (2023). The authors solicit any new information or comments which would improve future stock assessment reports. Draft versions of the 2022 stock assessment reports were reviewed by the Pacific Scientific Review Group (PSRG) at the March 2022 meeting and subject to a 90-day public comment period. These Stock Assessment Reports summarize information from a wide range of original data sources and an extensive bibliography of published sources are provided in each report. We recommend users of this document refer to and cite original literature sources cited within the stock assessment reports rather than citing this report or previous Stock Assessment Reports.