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Argos DCS System Use Agreement of the Month
– March 2016

U.S. Geological Survey – Alaska Science Center
Alaska Wildlife: Polar Bear and Walrus Research


USGS Polar Bear Research has three major objectives:

(1) Estimation of population size and trend;
(2) Description of movements; and
(3) Distribution patterns identification of maternal denning areas.
These traditional research foci will continue into the foreseeable future.

USGS Polar Bear Research, however, now focuses on understanding the impacts of a warming Arctic on polar bear populations and the survival strategies of polar bears in coping with habitat loss. Polar bears are captured in the spring or fall by darting them from helicopters. Once immobile, we fit selected polar bears with PTTs so that we can follow them wherever they go. As the Arctic sea ice is modified due to global climate change, and as increasing numbers of people and their activities occur within polar bear habitats, it is increasingly important to understand trends in numbers, survival patterns, movements, and maternal denning.

Satellite telemetry is critical in these endeavors. Because they live almost exclusively on the drifting ice, it is impossible to physically follow polar bears through their life cycle. Also, the hazards of flying over the unstable ice prevent aerial monitoring of their behaviors and activities. Satellite telemetry, therefore, is the key to unraveling the many mysteries surrounding polar bears, and is one of the most important tools upon which we rely for understanding the ways in which modifications of the Arctic are likely to impact them.

Since the first PTTs were attached to polar bears in autumn of 1985, we have collected tens of thousands of relocations of polar bears. Those relocations have become the basis of numerous published papers and other reports. These data formed the foundation of the USGS research to provide information to the Department of Interior for their decision to list polar bears as a threatened species under the US Endangered Species Act.

Walrus also occupy habitats which make them difficult to study through direct observations. Because walrus depend on sea ice for many aspects of their life history they too are susceptible to habitat loss from climate change. The proximity of sea ice to benthic foraging habitats appears to be especially important to walrus. USGS scientists depend on satellite telemetry to understand walrus movements and distribution and to assist in estimations of population size. Data from PTTs is allowing USGS scientist to begin to understand habitat use patterns and foraging ecology.

For both polar bears and walrus, we expect that satellite telemetry will be increasingly important as we face a changing Arctic in future years and decades.

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