Long-distance swimming by polar bears (Ursus maritimus) of the southern Beaufort Sea during years of extensive open water
Links
- More information: Publisher Index Page (via DOI)
- Download citation as: RIS | Dublin Core
Abstract
Polar bears (Ursus maritimus Phipps, 1774) depend on sea ice for catching marine mammal prey. Recent sea-ice declines have been linked to reductions in body condition, survival, and population size. Reduced foraging opportunity is hypothesized to be the primary cause of sea-ice-linked declines, but the costs of travel through a deteriorated sea-ice environment also may be a factor. We used movement data from 52 adult female polar bears wearing Global Positioning System (GPS) collars, including some with dependent young, to document long-distance swimming (>50 km) by polar bears in the southern Beaufort and Chukchi seas. During 6 years (2004-2009), we identified 50 long-distance swims by 20 bears. Swim duration and distance ranged from 0.7 to 9.7 days (mean = 3.4 days) and 53.7 to 687.1 km (mean = 154.2 km), respectively. Frequency of swimming appeared to increase over the course of the study. We show that adult female polar bears and their cubs are capable of swimming long distances during periods when extensive areas of open water are present. However, long-distance swimming appears to have higher energetic demands than moving over sea ice. Our observations suggest long-distance swimming is a behavioral response to declining summer sea-ice conditions.
Publication type | Article |
---|---|
Publication Subtype | Journal Article |
Title | Long-distance swimming by polar bears (Ursus maritimus) of the southern Beaufort Sea during years of extensive open water |
Series title | Canadian Journal of Zoology |
DOI | 10.1139/Z2012-033 |
Volume | 90 |
Issue | 5 |
Year Published | 2012 |
Language | English |
Publisher | National Research Council of Canada |
Publisher location | Ottawa, Canada |
Contributing office(s) | Alaska Science Center Biology MFEB |
Description | 14 p. |
First page | 663 |
Last page | 676 |
Online Only (Y/N) | N |
Additional Online Files (Y/N) | N |
Google Analytic Metrics | Metrics page |