What We Do

The Marine Mammals Management Program strives to keep Alaska sea otter populations and habitats healthy and ensure opportunities for viewing and legal non-commercial subsistence hunting. 

  • tracking sea otter population abundance, trends, and distribution using aerial and boat-based surveys
  • monitoring sea otter health, disease, and patterns of mortality by evaluating individuals that are healthy, stranded, or found dead
  • working with the Alaska SeaLife Center and Alaska volunteer stranding network to respond to live stranded and dead sea otters
  • assisting in placing orphaned pups with approved aquariums
  • assessing harvest patterns of sea otters legally hunted by Alaska Native peoples
  • conducting research examining the impact of sea otter recolonization on commercial and subsistence fisheries
  • working with Alaska Native organizations on issues of mutual concern and engage in Government to Government consultations 
  • working with Industry to ensure development is not in violation of the Marine Mammal Protection Act and Endangered Species Act 
  • reviewing applications for Incidental Harassment Authorization
  • responding to pollution events that may threaten sea otters
  • providing comments, interagency reviews, and testimony at public meetings
  • sitting on expert panels to provide the most current information on sea otter management and research
  • reviewing permits from researchers, photographers, documentary filmmakers, and aquariums requesting to work with sea otters 


Federal Register documents, Special Rule publications, Recovery Plans, and other regulatory documents for northern sea otter (Southwest Alaska, from Attu Island to Western Cook Inlet, including Bristol Bay, the Kodiak Archipelago, and the Barren Islands) are available on the northern sea otter species profile.

Peer Review Publications


Tinker, M.T., Schuette, P., Weitzman, B., Eisaguirre, J., & Beatty, W. (2023) The combined impact of killer whale consumptive and non-consumptive effects on northern sea otter population viability in the Western Aleutians Archipelago, Alaska. bioRxiv, 2023-01. https://doi.org/10.1101/2023.01.30.526353  


Bowen, L., Knowles, S., Lefebvre, K.; St. Martin, M., Murray, M., Kloecker, K., Monson, D., Weitzman, B., Ballachey, B., Coletti, H., Waters, S., and Cummings, C. (2022) Divergent Gene Expression Profiles in Alaskan Sea Otters: An Indicator of Chronic Domoic Acid Exposure? Oceans3:401-418. https://doi.org/10.3390/oceans3030027 

Flannery, B.G., Russ, O.L., St. Martin, M.L., Beatty, W.S., Worman, K.K., Garlich‐Miller, J.L., Gill, V.A., Lemons, P.L., Monson, D.H., Kloecker, K.A. and Esler, D. (2022) Genetic variation in sea otters (Enhydra lutris) from the North Pacific with relevance to the threatened Southwest Alaska Distinct Population Segment. Marine Mammal Science38(3), pp.858-880. https://doi.org/10.1111/mms.12899  

Leach, C. B., Williams, P. J., Eisaguirre, J. M., Womble, J. N., Bower, M. R., & Hooten, M. B. (2022) Recursive Bayesian computation facilitates adaptive optimal design in ecological studies. Ecology103(2), e03573. https://doi.org/10.1002/ecy.3573  

Traiger, S.B., Bodkin, J.L., Coletti, H.A., Ballachey, B., Dean, T., Esler, D., Iken, K., Konar, B., Lindeberg, M.R., Monson, D., Robinson, B., Suryan, R., and Weitzman, B. (2022) Evidence of increased mussel abundance related to the Pacific marine heatwave and sea star wasting. Marine Ecology43(4), p.e12715. https://doi.org/10.1111/maec.12715  


Beatty, W.S., St. Martin, M., & Wilson, R.R. (2021) Evaluating the current condition of a threatened marine mammal population: Estimating northern sea otter (Enhydra lutris kenyoni) abundance in southwest Alaska. Marine Mammal Science37(4), 1245-1260. https://doi.org/10.1111/mms.12807  

Eisaguirre, J.M., Williams, P.J., Lu, X., Kissling, M.L., Beatty, W.S., Esslinger, G.G., Womble, J.N. and Hooten, M.B. (2021) Diffusion modeling reveals effects of multiple release sites and human activity on a recolonizing apex predator. Movement Ecology9, pp.1-14. https://doi.org/10.1186/s40462-021-00270-w  

Esslinger, G.G., Robinson, B.H., Monson, D.H., Taylor, R.L., Esler, D., Weitzman, B.P., and Garlich-Miller, J. (2021) Abundance and distribution of sea otters (Enhydra lutris) in the southcentral Alaska stock, 2014, 2017, and 2019: U.S. Geological Survey Open-File Report 2021–1122, 19 p., https://doi.org/10.3133/ofr20211122

Tinker, M.T., J.L. Bodkin, L. Bowen, B. Ballachey, G. Bentall, A. Burdin, H. Coletti, G. Esslinger, B.B. Hatfield, M.C. Kenner, K. Kloecker, B. Konar, A.K. Miles, D.H. Monson, M.J. Murray, B.P. Weitzman, and J.A. Estes. (2021) Sea otter population collapse in southwest Alaska: assessing ecological covariates, consequences, and causal factors. Ecological Monographs 91(4):e01472. https://doi.org/10.1002/ecm.1472 

Wilson, R.R., St. Martin, M., & Beatty, W.S. (2021). A hierarchical distance sampling model to estimate spatially explicit sea otter density. Ecosphere12(9), e03666. https://doi.org/10.1002/ecs2.3666 


Tinker, Tim M., Gill, Verena A., Esslinger, George G., Bodkin, James, Monk Melissa, Mangel, Marc, Monson, Daniel H., Raymond, Wendel W. and Michelle L. Kissling. 2019. Trend and Carrying Capacity of Sea Otters in Southeast Alaska. The Journal of Wildlife Management 83(5): 1073-1089.  

Harley, John R., Gill, Verena A., Lee, Sunmi, Kannan, Kurunthachalam, Santana, Vanessa, Burek-Huntington, Kathy, and Todd M. O’Hara. 2019. Concentrations of organohalogens (PCBs, DDTs, PBDEs) in hunted and stranded Northern sea otters (Enhydra lutris kenyoni) in Alaska from 1992 to 2010: Links to pathology and feeding ecology. Science of the Total Environment 691(15): 789-798. 

Raymond, Wendel W., Tinker, Tim M., Kissling, Michelle L., Benter, Brad, Gill, Verena A. and Ginny L. Eckert. 2019. Locationspecific factors influence patterns and effects of subsistence sea otter harvest in Southeast Alaska. Ecosphere 10(9).

VanWormer, E., Mazet, J.A.K., Hall, A. et al. 2019. Viral emergence in marine mammals in the North Pacific may be linked to Arctic sea ice reduction. Scientific Reports 9,15569.


Newsome, S.D. M.T Tinker, V.A. Gill, A.M. Doroff, L. Nichol, J. Bodkin. 2015. The interaction of intraspecific competition and habitat on individual diet specialization: a near range-wide examination of sea ottersOecologia 178: 45-59.


Burek, K.A., V.A. Gill, and D.S. Bradway. 2014. The first case of locally acquired disseminated Histoplasmosis in Alaska and in a free-ranging marine mammalJournal of Wildlife Diseases 50(2): 389-392. 

Carrasco, S.E., B.B. Chomel, V.A. Gill, A.M. Doroff, M.A. Miller, K.A. Burek, R.W. Kasten, B.A. Byrne, T. Goldstein, J.A.K. Mazet. 2014. Bartonella spp. Exposure in Northern and Southern Sea Otters in Alaska and CaliforniaJournal of Vector-Borne and Zoonotic Diseases 14(12): 831-837.

Carrasco, S.E., B.B. Chomel, V.A. Gill, R.W. Kasten, R.G. Maggi, E.B. Breitschwerdt, B.A. Byrne, K.A. Burek-Huntington, M.A. Miller, T. Goldstein, J.A.K. Mazet. 2014Novel Bartonella Infection in Northern and Southern Sea Otters (Enhydra lutris kenyoni and Enhydra lutris nereis). Veterinary Microbiology 170: 325-334. 

Marshall, C. D., K. Rozas, B. Kot, and V.A. Gill.  2014. Innervation Patterns of Sea Otter (Enhydra lutris) Mystacial Follicle-Sinus Complexes: Support For An Expanded Facial Somatosensory CortexFrontiers in Neuroanatomy 8(121): 1-8.  

Goertz C.E.C., R. Walton, N. Rouse, J. Belovarac, K. Burek-Huntington, V. Gill, R. Hobbs, C. Xavier, N. Garrett, and P. Tuomi. 2013. Vibrio parahaemolyticus, a Climate Change Indicator in Alaska Marine Mammals. In: F.J. Mueter, D.M.S. Dickson, H.P. Huntington, J.R. Irvine, E.A. Logerwell, S.A. MacLean, L.T. Quakenbush, and C. Rosa, eds. 2013. Responses of Arctic Marine Ecosystems to Climate Change. Alaska Sea Grant, University of Alaska Fairbanks.


Larson, S.D., Z.N. Hoyt, G.L. Eckert, and V.A. Gill. 2013. Impacts of sea otter predation on commercially important sea cucumbers (Parastichopus californicus) in Southeast AlaskaCanadian Journal of Fisheries and Aquatic Sciences 70:1498-1507.


Counihan Edgar, K., V.A. Gill, A.M. Doroff, K.A. Burek Huntington, W. A. Miller, P.L.Shewmaker, S. Jang, E.C. Goertz, P.A. Tuomi, M.A. Miller, D. Jessup, and B.A. Byrne. 2012. Genotypic Characterization of Streptococcus infantarius subspecies coli Isolates from Sea Otters with Infective Endocarditis and/or Septicemia and from Environmental Mussel Samples. Journal of Clinical Microbiology 50(12):4131-4133.

Tseng, M., M. Fleetwood, A. Reed, V.A. Gill, R.K. Harris, R.B. Moeller, T.P. Lipscomb, J.A.K. Mazet, and T. Goldstein. 2012. Mustelid Herpesvirus-2, a novel herpes infection in northern sea otters (Enhydra lutris kenyoni). Journal of Wildlife Diseases 


Brownstein, D., M.A. Miller, S.C. Oates, B.A. Byrne, S. Jang, M.J. Murray, D.A. Jessup, and V.A. Gill. 2011. Antimicrobial susceptibility of bacterial isolates from sea otters (Enhydra lutris). Journal of Wildlife Diseases 47(2): 278-292.

Goldstein, T., V.A. Gill, P. Tuomi, D. Monson, A. Burdin, P.A. Conrad, J.L Dunn, C. Field, C. Johnson, D.A. Jessup, J. Bodkin and A.M. Doroff. 2011. Assessment of clinical pathology and pathogen exposure in sea otters (Enhydra lutris) bordering the threatened population in Alaska. Journal of Wildlife Diseases 47(3): 579–592.


Goldstein, T., J.A.K. Mazet, V.A. Gill, A.M. Doroff, K.A. Burek, and J.A. Hammond. 2009. Phocine distemper virus in northern sea otters in the Pacific Ocean, Alaska, USA. Journal of Emerging Diseases 15(6): 925-927.

Hart, K, V.A. Gill, and K. Kannan. 2009Temporal Trends (1992-2007) of Perfluorinated Chemicals (PFCs) in Northern Sea Otters (Enhydra lutris kenyoni) from South-central AlaskaArchives of Environmental Contamination and Toxicology 56(3): 607-614.

Von Biela, V.R., V.A. Gill, J.L. Bodkin, and J.M. Burns. 2009. Phenotypic plasticity in the average age of first reproduction in northern sea otters (Enhydra lutris kenyoni). Journal of Mammalogy 90(5):1224-1231.

Von Biela, V.R, W. J. Testa, V.A. Gill, and J. M. Burns. 2008. Evaluating cementum annuli to determine past reproduction in northern sea otters. Journal of Wildlife Management 72(3): 618-624.

Burn, D.M. and A.M. Doroff. 2005Decline in sea otter (Enhydra lutris) populations along the Alaska Peninsula, 1986-2001. Fishery Bulletin 103: 270-279.

Estes, J.A., M.T. Tinker, A.M. Doroff, and D.M. Burn. 2005Continuing sea otter population declines in the Aleutian archipelagoMarine Mammal Science 21:169-172.

Burn, D.M., A.M. Doroff, M.T. Tinker. 2003. Estimated carrying capacity and pre-decline abundance of sea otters (Enhydra lutris kenyoni) in the Aleutian islands. Northwestern Naturalist 84(3):145-148.

Doroff, A.M., J.A. Estes, M.T. Tinker, D.M. Burn, and T.J. Evans. 2003. Sea otter population declines in the Aleutian archipelago. Journal of Mammalogy 84(1): 55-64.

Gorbics, C.S. and J.L. Bodkin. 2001. Stock structure of sea otters (Enhydra lutris kenyoni) in Alaska. Marine Mammal Science 17(3): 632-647.

Burn, D.M. 1994. Boat-based population surveys of sea otters in Prince William Sound. Pp. 61-80 in: Marine Mammals and the Exxon Valdez. T. Loughlin (Ed.) Academic Press, Inc.

DeGange, A.R., A.M. Doroff, and D.H. Monson. 1994. Experimental recovery of sea otter carcasses at Kodiak Island, Alaska, following the Exxon Valdez oil spill. Marine Mammal Science 10(4):492-496.

Doroff, A.M. and J.L. Bodkin. 1994. Sea otter foraging behavior and hydrocarbon levels in prey following the Exxon Valdez oil spill in Prince William Sound, Alaska. In: Marine Mammals and Oiling. Ed. T.R. Loughlin. Academic Press.

Doroff, A.M. and A.R. DeGange. 1994. Sea otter prey composition and foraging success in the northern Kodiak archipelago. Fishery Bulletin 92:704-710 (1994).

Garrott, R.A., L.L. Eberhardt, and D.M. Burn. 1993. Mortality of sea otters in Prince William Sound following the Exxon Valdez oil spill. Marine Mammal Science 9(4):343-359.

Technical Reports

Schuette, P. Eisaguirre, J., Weitzman, B., Power, C., Wetherington, E., Cate, J., Womble, J., Pearson, L., Melody, D., Merriman, C., Hanks, K., & Esslinger, G. (2023) Northern Sea Otter (Enhydra lutris kenyoni) Population Abundance and Distribution across the Southeast Alaska Stock Summer 2022. U.S. Fish & Wildlife Service, Marine Mammals Management Technical Report: MMM 2023-01. 41pp. 

Southeast Sea Otter Stakeholder Meeting. 2020. Final Report of the 2019 Southeast Sea Otter Stakeholder Working Group Meeting. November 6, 2019. Juneau Alaska. U.S. Fish &Wildlife Service Technical Report MMM 2020-01.

Garlich-Miller, J.L., G.G. Esslinger, and B.P. Weitzman. 2018. Aerial Surveys of Sea Otters (Enhydra lutris) in Lower Cook Inlet, Alaska, May 2017. U.S. Fish and Wildlife Service, Marine Mammals Management Technical Report: MMM 2018-01. 22pp 

Gill, V.A., A.M. Doroff, and D. Burn. 2009. Aerial Surveys of Sea Otters Enhydra lutris in Kachemak, Alaska 2008. U.S. Fish and Wildlife Service report for Army Corps of Engineers. MIPR # WC1JUW80880784. 21pp.

Gill, V.A. and D. Burn. 2007. Aerial Surveys of Sea Otters Enhydra lutris in Yakutat Bay, Alaska 2005. U.S. Fish and Wildlife Service, Marine Mammals Management Technical Report: MMM 2007-01. 18pp.

Von Biela, V.R. and V.A. Gill. 2007. Analysis of the Sea Otter (Enhydra lutris) Reproductive Tract: A Methods Manual. U.S. Fish and Wildlife Service, Marine Mammals Management Technical Report: MMM 2007-02. 24pp.

Gill, V.A. 2006. Marine Mammal Unusual Mortality event initiation protocol for northern sea otters. Unpublished USFWS report. 11pp.

Burek, K.A. V.A. Gill, N. Bronson, and P. Tuomi. 2005. A pictorial guide to sea otter anatomy and necropsy findings.  USFWS unpublished report. 44pp.

Ballachey, B.E., C.S. Gorbics, and A.M. Doroff. 2001. Sea otter mortality in Orca Inlet, Prince William Sound, Alaska, winter 1995-1996. U.S. Fish and Wildlife Service, Marine Mammals Management Technical Report: MMM 01-1. 23 pp.

U.S. Fish and Wildlife Service. 2001a. Standard methods to assess over winter mortality trends in sea otter populations in Alaska. Marine Mammals Management, Anchorage, Alaska. 7 pp.

U.S. Fish and Wildlife Service. 2001b. Population trend surveys as an index to abundance and distribution of sea otters: a standard protocol in Alaska. Marine Mammals Management, Anchorage, Alaska. 10 pp.

Doroff, A.M. and M. Roy. 1999. Sea Otter Surveys of Izembek Lagoon, Alaska: a Pilot Study. U.S. Fish and Wildlife Service, Marine Mammals Management, Anchorage, Alaska. 6 pp.

Doroff, A.M. and C. Gorbics. 1997. Sea otter surveys of Yakutat Bay and adjacent Gulf of Alaska coastal areas - Cape Hinchinbrook to Cape Spencer 1995-1996. Final Report to Minerals Management Service. Interagency Agreement No. 05059. 23 pp.

Doroff, A.M. and D. Mulcahy. 1997. A field guide to general necropsy and tissue collection for sea otters (Enhydra lutris) in Alaska. U.S. Fish and Wildlife Service, Marine Mammals Management Technical Report MMM 97-3. 49 pp.

Evans, T.J., D.M. Burn, and A.R. DeGange. 1997. Distribution and relative abundance of sea otters in the Aleutian archipelago. U.S. Fish and Wildlife Service, Marine Mammals Management Technical Report MMM 97-5. 

Doroff, A.M. and J.L. Bodkin. 1996. Sea otter foraging behavior and hydrocarbon levels in prey following the Exxon Valdez oil spill in Prince William Sound, Alaska. Exxon Valdez Oil Spill State/Federal Nat Natural Resources Damage Assessment Marine Mammal Study 6-8. Final Report. 33 pp.

Doroff, A.M. and A.R. DeGange. 1995. Experiments to determine drift patterns and rates of recovery of sea otter carcasses following the Exxon Valdez oil spill. Exxon Valdez Oil Spill State/Federal Natural Resources Damage Assessment Marine Mammal Study 6-9. Final Report. 13 pp.

U.S. Fish and Wildlife Service. 1994. Conservation plan for the sea otter in Alaska. Marine Mammals Management, Anchorage, Alaska. 44 pp.

Doroff, A.M., A.R. DeGange, C. Lensink, B.E. Ballachey, J.L. Bodkin, and D. Bruden. 1993. Recovery of sea otter carcasses following the Exxon Valdez oil spill. Pp. 285-288 in: Exxon Valdez Oil Spill Symposium, Program and Abstracts. 365 pp.