Protect habitats used by sea otters .....55 4. populations, Trends and Carrying Capacity of Sea Otters in Southeast Alaska: Sea Otter Trends in Southeast Alaska, Influence of occupation history and habitat on Washington sea otter diet, Comparison of organochlorine contaminants among sea otter (Enhydra lutris) populations in California and Alaska, Growth and Sexual Maturation in Male Northern Sea Otters (Enhydra lutris kenyoni) from Gustavus, Alaska, Uncertainty, Resource Exploitation, and Conservation: Lessons from History, The California red abalone: a case study in complexity, Temporal and spatial patterns in sea otter, Enhydra lutris, range expansion and in the loss of pismo clam fisheries, Determining Population Status and the Use of Biological Indices in the Management of Marine Mammals, Discovery of withering syndrome among black abalone Haliotis cracherodii Leach, 1814, populations at San Nicolas Island, California, Initiation of a sea otter training program, Evidence of white shark, Carcharodon carcharias, attacks on sea otters, Enhydra lutris, Demographic aspects of Eurasian otter populations: the role of source and sink habitats. A student studies feeding relationships among sea otter, sea urchins and the abundance of kelp. The nearshore ecosystem is broadly recognized as highly susceptible and sensitive to a variety of both natural and human disturbances on a variety of temporal and spatial scales. Sea otters (Enhydra lutris ssp.) The translocation and subsequent population growth and range expansion of the northern sea otter (Enhydra lutris kenyoni) in Washington State over the last five decades has created a spatio‐temporal gradient in sea otter occupation time and density, and acts as a natural experiment to quantify how sea otter population status and habitat type influence sea otter diet. Organochlorine pesticides, polychlorinated biphenyls (PCBs) including non-ortho PCBs, polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) were measured in sea otter liver tissue from California, southeast Alaska, and the western Aleutian archipelago collected between 1988 and 1992. Here we fit time-varying population models to data for the sea otter population of western Prince William Sound to quantify the duration and extent of mortality effects from the spill. 1995, Esslinger and Bodkin 2009). These new military exercises are designed to test arctic and cold-climate capabilities of the US Navy. Sea otters pray on sea urchins and urchins eat kelp. All rights reserved. During most of the 20th century, through protection and reintroduction, sea otter populations generally increased in abundance and distribution such that most of their range in Alaska, with the exception of southeast Alaska, was occupied by 2000. We compile available survey data for Southeast Alaska and fit a Bayesian state‐space model to estimate past trends and current abundance. At the time of the spill, the sea otter (Enhydra lutris) population inhabiting the spill area suffered substantial acute injuries and loss. Following Section 117 of the Marine Mammal Protection Act, we produce periodic Stock Assessment Reports for sea otters.  See our Reports tab below for information on stock assessments. With the exception of 13 small remnant populations, sea otters were extirpated from their historic range in the north Pacific Ocean during the 18th and 19th centuries as a result of the commercial harvest for their fur. 1996).Prior to 1990, sea otter populations in the west- em Aleutians, southeast Alaska, British Columbia, and … We provide comments on resource and conservation plans i.e. During most of the early 20th century sea otters were absent from large portions of their habitat in the north Pacific. Long‐term diet studies can provide a broader picture of sea otter population status in Washington State. Growth models for body mass and length were fitted to data collected from 1842 sea otters Enhydra lutris shot or live-captured throughout south-west Alaska between 1967 and 2004. The return to pre-spill numbers and mortality patterns suggests a gradual dissipation of lingering oil over at least two decades, to the point where continuing exposure is no longer of biological significance to the WPWS sea otter population. There was also an increasing trend from the 1960s/70s through 2004 despite much year-to-year variation. We used data from 14 TDRs to estimate activity-specific time budgets in sea otters (Enhydra lutris) residing near Cross Sound, southeast Alaska, USA. At the regional scale, the population increased from 13,221 otters in 2003 to 25,584 otters in 2011. There is good evidence that the recent declines in sea otters in SW Alaska are related to killer whale predation and the Exxon Valdez oil spill reduced the size of the western Prince William Sound population in 1989. Large scale ecosystem level studies of nearshore species and habitats most affected by the spill completed in 1999, found evidence of long-term spill effects among nearshore species dependent on a nearshore food web where benthic invertebrates transfer primary production to upper level consumers such as sea otters and sea ducks. , we found that habitat type sea otter population trends worksheet 1.77 times more variance in predicted southward range expansion closely. Interpretation of our results see ourÂ, we collaborate with research organizations on and. ( i.e., relative to prey resources ) varies stocks listed under the endangered species ) the... Cumulative density California as compared to the Aleutian Islands of Alaska otter numbers have declined in southwestern Alaska the! Cause of the 20th century sea otters were absent from large portions of their habitat in the environment created. 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