1.0 DCPLUS 20260629 20010600 20260629 20010600 https://www.arcgis.com/home/item.html?id=076f2121aa8f4f88b6dd1d96ca992bca 076f2121aa8f4f88b6dd1d96ca992bca Feature Service https://services6.arcgis.com/2DGR1sZBUvcPcd8Z/arcgis/rest/services/cetacean_data/FeatureServer Deepwater Horizon Cetacean Mortalities CETCETACEANpopulationdeepwater horizonStock assessment reportSEFSCDWHmortality This table contains information about the mortalities caused for cetaceans in the Gulf byt the Deepwater Horizon oil spill This table was created with information from the <a target='_blank' href='https://www.fisheries.noaa.gov/s3/2026-04/atlantic_2024_mmsars.pdf' rel='nofollow ugc noopener noreferrer'>2024 Stock Assessment Report. </a> Appendix VI: Estimates of Human-caused Mortality Resulting from the Deepwater Horizon Oil Spill Estimates of human-caused mortality are a result of a population model developed to estimate the injury and time to recovery for stocks affected by the Deepwater Horizon (DWH) oil spill, taking into account long-term impacts resulting from mortality, reproductive failure, reduced survival rates, and the proportion of the stock exposed to DWH oil (DWH MMIQT 2015).<p style='background-color:rgb(255, 255, 255); box-sizing:border-box; color:rgb(0, 0, 0); font-family:"Open Sans", sans-serif; font-size:16px; font-style:normal; font-variant-caps:normal; font-variant-ligatures:normal; font-weight:400; letter-spacing:normal; margin:0px 0px 10px; text-align:start; text-decoration-color:initial; text-decoration-style:initial; text-indent:0px; text-transform:none; word-spacing:0px;'>NOAA Fisheries prepares marine mammal stock assessment reports annually, as directed by the <a style='background-color:transparent; box-sizing:border-box; color:rgb(0, 67, 145);' target='_blank' href='https://www.fisheries.noaa.gov/topic/laws-policies/marine-mammal-protection-act' rel='nofollow ugc noopener noreferrer'>Marine Mammal Protection Act</a>. The reports are prepared in consultation with one or more of three regional <a style='background-color:transparent; box-sizing:border-box; color:rgb(0, 67, 145);' target='_blank' href='https://www.fisheries.noaa.gov/national/marine-mammal-protection/scientific-review-groups' rel='nofollow ugc noopener noreferrer'>Scientific Review Groups</a>.<p style='background-color:rgb(255, 255, 255); box-sizing:border-box; color:rgb(0, 0, 0); font-family:"Open Sans", sans-serif; font-size:16px; font-style:normal; font-variant-caps:normal; font-variant-ligatures:normal; font-weight:400; letter-spacing:normal; margin:0px 0px 10px; text-align:start; text-decoration-color:initial; text-decoration-style:initial; text-indent:0px; text-transform:none; word-spacing:0px;'>NOAA Fisheries currently maintains stock assessment reports for 261 marine mammal stocks, of which 21 revised reports are included for the 2024 cycle. The final 2024 Marine Mammal Stock Assessment Reports are <a style='background-color:transparent; box-sizing:border-box; color:rgb(0, 67, 145);' target='_blank' href='https://www.federalregister.gov/documents/2026/04/22/2026-07791/final-2024-marine-mammal-stock-assessment-reports' rel='nofollow ugc noopener noreferrer'>published in the Federal Register</a>.<p style='background-color:rgb(255, 255, 255); box-sizing:border-box; color:rgb(0, 0, 0); font-family:"Open Sans", sans-serif; font-size:16px; font-style:normal; font-variant-caps:normal; font-variant-ligatures:normal; font-weight:400; letter-spacing:normal; margin:0px 0px 10px; text-align:start; text-decoration-color:initial; text-decoration-style:initial; text-indent:0px; text-transform:none; word-spacing:0px;'>NOAA Fisheries released the draft reports for public review and comment, which concluded in June 2025. The <a style='background-color:transparent; box-sizing:border-box; color:rgb(0, 67, 145);' target='_blank' href='https://www.federalregister.gov/documents/2026/04/22/2026-07791/final-2024-marine-mammal-stock-assessment-reports' rel='nofollow ugc noopener noreferrer'>Federal Register Notice</a> includes responses to the substantive comments received.<p style='background-color:rgb(255, 255, 255); box-sizing:border-box; color:rgb(0, 0, 0); font-family:"Open Sans", sans-serif; font-size:16px; font-style:normal; font-variant-caps:normal; font-variant-ligatures:normal; font-weight:400; letter-spacing:normal; margin:0px 0px 10px; text-align:start; text-decoration-color:initial; text-decoration-style:initial; text-indent:0px; text-transform:none; word-spacing:0px;'>Stocks are classified under two categories: “strategic” and “non-strategic.” A strategic stock is defined as at least one of the following:<ul><li>A marine mammal stock for which the level of direct human-caused mortality exceeds the potential biological removal level</li><li>A stock which, based on the best scientific information available, is declining and is likely to be listed as a threatened species under the Endangered Species Act within the foreseeable future</li><li>A stock which is listed as a threatened or endangered species under the Endangered Species Act, or is designated as depleted under the Marine Mammal Protection Act</li></ul>Hayes, S. A., Josephson, E., Maze-Foley, K., Rosel, P. E., & McCordic, J. (Eds.). (2025). U.S. Atlantic and Gulf of America marine mammal stock assessments 2024 (NEFSC Technical Memorandum 336). National Marine Fisheries Service, Northeast Fisheries Science Center. <a target='_blank' href='https://www.fisheries.noaa.gov/s3/2026-04/atlantic_2024_mmsars.pdf' rel='nofollow ugc noopener noreferrer'>https://www.fisheries.noaa.gov/s3/2026-04/atlantic_2024_mmsars.pdf</a> Hayes, S. A., Josephson, E., Maze-Foley, K., Rosel, P. E., & McCordic, J. (Eds.). (2025). U.S. Atlantic and Gulf of America marine mammal stock assessments 2024 (NEFSC Technical Memorandum 336). National Marine Fisheries Service, Northeast Fisheries Science Center. https://www.fisheries.noaa.gov/s3/2026-04/atlantic_2024_mmsars.pdf CC-BY 076f2121aa8f4f88b6dd1d96ca992bca https://services6.arcgis.com/2DGR1sZBUvcPcd8Z/arcgis/rest/services/cetacean_data/FeatureServer Feature Service