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Title: Polar bear's range dynamics and survival in the Holocene
Polar bear (Ursus maritimus) is the apex predator of the Arctic, largely dependent on sea-ice. The expected disappearance of the ice cover of the Arctic seas by the mid 21st century is predicted to cause a dramatic decrease in the global range and population size of the species. To place this scenario against the backdrop of past distribution changes and their causes, we use a fossil dataset to investigate the polar bear’s past distribution dynamics during the Late Glacial and the Holocene. Fossil results indicate that during the last deglaciation, polar bears were present at the southwestern margin of the Scandinavian Ice Sheet, surviving until the earliest Holocene. There are no Arctic polar bear findings from 8,000-6,000 years ago (8-6 ka), the Holocene’s warmest period. However, fossils that date from 8-9 ka and 5-6 ka suggest that the species likely survived this period in cold refugia located near the East Siberian Sea, northern Greenland and the Canadian Archipelago. Polar bear range expansion is documented by an increase in fossils during the last 4,000 years in tandem with cooling climate and expanding Arctic sea ice. The results document changes in polar bear’s distribution in response to Late Glacial and Holocene Arctic temperature and sea ice trends.  more » « less
Award ID(s):
2110923
PAR ID:
10538049
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Quaternary Science Reviews
Volume:
317
Issue:
C
ISSN:
0277-3791
Page Range / eLocation ID:
108277
Subject(s) / Keyword(s):
polar bear Holocene Arctic sea ice fossils distribution dynamics
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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