Polar Biology

, Volume 40, Issue 4, pp 753–763 | Cite as

Summer refugia of polar bears (Ursus maritimus) in the southern Beaufort Sea

Original Paper

Abstract

Climate change is altering habitats and causing changes to species behaviors and distributions. Rapid changes in Arctic sea ice ecosystems have increased the need to identify critical habitats for conservation and management of species such as polar bears (Ursus maritimus). We examined the distribution of adult female and subadult male and female polar bears tracked by satellite telemetry (n = 64 collars) in the southern Beaufort Sea, Canada, to identify summer refugia in 2007–2010. Using utilization distributions, we identified terrestrial and sea ice areas used as summer refugia when nearshore sea ice melted. Habitat use areas varied between months, but interannual variation was not significant. Overall, bears made high use of ice over shallow waters, and bears that remained near terrestrial areas used sea ice (presumably to hunt from) when it was available. The majority of the bears remained on sea ice during summer and used the edge of the pack ice most notably west of Banks Island, Canada. A mean of 27 % (range 22–33 %) of bears used terrestrial areas in Alaska and use was concentrated near the remains of subsistence harvested bowhead whales (Balaena mysticetus). Energetic expenditure is anticipated to increase as bears are required to travel further on a seasonal basis.

Keywords

Polar bear Ursus maritimus Beaufort Sea Distribution Sea ice Kernel density 

Notes

Acknowledgments

We gratefully acknowledge support from ArcticNet, Canadian Association of Zoos and Aquariums, Canadian Circumpolar Institute’s Boreal Alberta Research, Canadian Wildlife Federation, Environment Canada, Hauser Bears, Inuvialuit Game Council, Natural Sciences and Engineering Research Council of Canada, Northwest Territories Department of Environment and Natural Resources—Inuvik Region, Polar Bears International, Polar Continental Shelf Project, Quark Expeditions Ltd., United States Department of the Interior (Bureau of Ocean Energy Management), and World Wildlife Fund (Canada and International). We furthermore thank Marie Auger-Méthé, Oliver Barker, Seth Cherry, Stephen Hamilton, Alysa McCall, Peter Molnár, Nick Pilfold, and Vicki Sahanatien for assistance in the field and pilot Mike Woodcock.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Department of Biological SciencesUniversity of AlbertaEdmontonCanada
  2. 2.Department of Environment and Natural ResourcesGovernment of Northwest TerritoriesInuvikCanada

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