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Contaminant Exposure and Effects-Terrestrial Vertebrates database (CEE-TV)

Information about ecotoxicological exposure and its effects on terrestrial vertebrates residing in estuarine and coastal habitats like the Atlantic, Gulf and Pacific Coasts, Alaska and Hawaii, as well as the Great Lakes. These vertebrates include birds, mammals, amphibians and reptiles. The data is a compilation of results from computerized More...

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Using Genetic Modeling to Assess the Health and Status of Manatee Populations

Biologists in the Sirenia Project at the U.S. Geological Survey (USGS) Florida Integrated Science Center (FISC) in Gainesville, FL, are currently identifying and mapping the genetic material of manatees. Their goal is to better understand and predict the manatee's ability to react to environmental stimuli, such as prolonged periods of cold More...

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Sea Otter Mortality

Recent increases in the frequency and variety of infectious diseases in the southern sea otter may jeopardize the population recovery of this threatened species. This information sheet includes a list of selected publications.

  • sea otter with its head poking out of the ocean

Sea Otter Studies at WERC

Sea otters (Enhydra lutris) are keystone predators in the nearshore environment of the eastern Pacific Ocean, in a food web composed of sea otter, sea urchin, and kelp forest. Without sea otters, the kelp forest can be overgrazed by sea urchins, which in turn can affect other species that depend on this ecosystem. This resource provides links to More...

  • A sea otter floats on its back while grooming

Using radiotelemetry to allocate harvests among polar bear stocks occupying the Beaufort Sea region

This study is a new analytical procedure that quantifies the degree of overlap between adjacent populations of polar bears, and provides science for better management of the harvest of polar bears in the Beaufort and Chukchi Seas. This new analytical approach allows previously accepted population management units to be subdivided in ways that will More...

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Quantitative Threats Analysis for the Florida Manatee (Trichechus manatus latirostris)

This report assesses and forecasts the status of the Florida manatee population over 50 to 150 years, and examines the relative roles that different threats play in determining the status of these marine mammals, in cooperation with scientists at the Florida Fish and Wildlife Conservation Commission's Fish and Wildlife Research Institute (FWC). More...

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National Resources Monitoring Partnership (NRMP)

Natural resource managers face complex decisions that require a clear understanding of the status of wildlife populations and their habitats. Monitoring is key to making effective management decisions and evaluating the outcomes of those decisions. The goal of NRMP is to improve the accessibility of monitoring efforts to resource managers to aid More...

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National Resources Monitoring Partnership (NRMP) Newsletter

Natural Resource Monitoring Partnership (NRMP) is a collaborative effort by the natural resource management community to improve monitoring efforts in order to support effective evaluation and decision-making by sharing information on monitoring projects and protocols. The Natural Resource Monitoring Partnership was built for easy access to More...

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Sea otter population status and changes in Alaska

A web page to introduce research by the USGS Alaska Science Center on sea otter population status and changes in Alaska. Provides some background on why the research is needed, research objectives, and a listing of publications by project staff.

  • full body view of sea otter under water

Polar Bear Research at the Alaska Science Center - Abundance and Vital Rates Projects

This web page links to resources related to the abundance and vital rates of polar bears. It includes Polar bear population status in the southern Beaufort Sea, and Survival and population size of polar bears in relation to earlier sea ice breakup. The site also links to resources that deal with tracking polar bears via satellite, polar bear-sea More...

  • Male polar bear (Ursus maritimus)

Retrospective evaluation of Exxon Valdez oil spill Trustee Council sponsored sea otter studies

An extensive and diverse array of studies were implemented concurrent with and for several years following the Exxon Valdez oil spill to determine the acute and chronic effects to sea otters. In part, this paper describes what activities relative to sea otters should take place prior to, during, and following another spill similar to the Exxon More...

  • sea otter in ocean at time of oil spill

Using Demography and Movement Behavior to Predict Range Expansion of the Southern Sea Otter

Management agencies are interested in the development of a realistic predictive model of the southern sea otter population recovery and range expansion into southern California, as this would facilitate the informed assessment of potential impacts of sea otters on important industries (e.g., fisheries, eco-tourism), potential negative effects of More...

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