Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic
Polar bears are dependent on sea ice for survival. Climate warming in the Arctic has caused significant declines in coverage and thickness of sea ice in the polar basin and progressively earlier breakup in some areas. In four populations of polar bears in the eastern Canadian Arctic (including Weste...
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ftnasantrs:oai:casi.ntrs.nasa.gov:20060020227 2023-05-15T14:50:04+02:00 Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic Parkinson, Claire L. Stirling Ian Unclassified, Unlimited, Publicly available [2006] application/pdf http://hdl.handle.net/2060/20060020227 unknown Document ID: 20060020227 http://hdl.handle.net/2060/20060020227 Copyright, Distribution as joint owner in the copyright CASI Meteorology and Climatology 2006 ftnasantrs 2018-06-09T23:00:36Z Polar bears are dependent on sea ice for survival. Climate warming in the Arctic has caused significant declines in coverage and thickness of sea ice in the polar basin and progressively earlier breakup in some areas. In four populations of polar bears in the eastern Canadian Arctic (including Western Hudson Bay), Inuit hunters report more bears near settlements during the open water period in recent years. These observations have been interpreted as evidence of increasing population size, resulting in increases in hunting quotas. However, long-term data on the population size and condition of polar bears in Western Hudson Bay, and population and harvest data from Baffin Bay, make it clear that those two populations at least are declining, not increasing. While the details vary in different arctic regions, analysis of passive-microwave satellite imagery, beginning in the late 1970s, indicates that the sea ice is breaking up at progressively earlier dates, so that bears must fast for longer periods during the open water season. Thus, at least part of the explanation for the appearance of more bears in coastal communities is likely that they are searching for alternative food sources because their stored body fat depots are being exhausted. We hypothesize that, if the climate continues to warm as projected by the IPCC, then polar bears in all five populations discussed in this paper will be stressed and are likely to decline in numbers, probably significantly so. As these populations decline, there will likely also be continuing, possibly increasing, numbers of problem interactions between bears and humans as the bears seek alternate food sources. Taken together, the data reported in this paper suggest that a precautionary approach be taken to the harvesting of polar bears and that the potential effects of climate warming be incorporated into planning for the management and conservation of this species throughout the Arctic. Other/Unknown Material Arctic Baffin Bay Baffin Bay Baffin Hudson Bay inuit Sea ice Ursus maritimus NASA Technical Reports Server (NTRS) Arctic Baffin Bay Hudson Hudson Bay |
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NASA Technical Reports Server (NTRS) |
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Meteorology and Climatology |
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Meteorology and Climatology Parkinson, Claire L. Stirling Ian Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic |
topic_facet |
Meteorology and Climatology |
description |
Polar bears are dependent on sea ice for survival. Climate warming in the Arctic has caused significant declines in coverage and thickness of sea ice in the polar basin and progressively earlier breakup in some areas. In four populations of polar bears in the eastern Canadian Arctic (including Western Hudson Bay), Inuit hunters report more bears near settlements during the open water period in recent years. These observations have been interpreted as evidence of increasing population size, resulting in increases in hunting quotas. However, long-term data on the population size and condition of polar bears in Western Hudson Bay, and population and harvest data from Baffin Bay, make it clear that those two populations at least are declining, not increasing. While the details vary in different arctic regions, analysis of passive-microwave satellite imagery, beginning in the late 1970s, indicates that the sea ice is breaking up at progressively earlier dates, so that bears must fast for longer periods during the open water season. Thus, at least part of the explanation for the appearance of more bears in coastal communities is likely that they are searching for alternative food sources because their stored body fat depots are being exhausted. We hypothesize that, if the climate continues to warm as projected by the IPCC, then polar bears in all five populations discussed in this paper will be stressed and are likely to decline in numbers, probably significantly so. As these populations decline, there will likely also be continuing, possibly increasing, numbers of problem interactions between bears and humans as the bears seek alternate food sources. Taken together, the data reported in this paper suggest that a precautionary approach be taken to the harvesting of polar bears and that the potential effects of climate warming be incorporated into planning for the management and conservation of this species throughout the Arctic. |
author |
Parkinson, Claire L. Stirling Ian |
author_facet |
Parkinson, Claire L. Stirling Ian |
author_sort |
Parkinson, Claire L. |
title |
Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic |
title_short |
Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic |
title_full |
Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic |
title_fullStr |
Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic |
title_full_unstemmed |
Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic |
title_sort |
possible effects of climate warming on selected populations of polar bears (ursus maritimus) in the canadian arctic |
publishDate |
2006 |
url |
http://hdl.handle.net/2060/20060020227 |
op_coverage |
Unclassified, Unlimited, Publicly available |
geographic |
Arctic Baffin Bay Hudson Hudson Bay |
geographic_facet |
Arctic Baffin Bay Hudson Hudson Bay |
genre |
Arctic Baffin Bay Baffin Bay Baffin Hudson Bay inuit Sea ice Ursus maritimus |
genre_facet |
Arctic Baffin Bay Baffin Bay Baffin Hudson Bay inuit Sea ice Ursus maritimus |
op_source |
CASI |
op_relation |
Document ID: 20060020227 http://hdl.handle.net/2060/20060020227 |
op_rights |
Copyright, Distribution as joint owner in the copyright |
_version_ |
1766321150535663616 |