Observations of a wild polar bear (Ursus maritimus) successfully fishing Arctic charr (Salvelinus alpinus) and Fourhorn sculpin (Myoxocephalus quadricornis)
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Abstract
Polar bears, Ursus maritimus, throughout their range, are nutritionally dependent on ringed (Phoca hispida) and bearded seals (Erignathus barbatus), which are predominantly caught on the sea ice. Other marine prey species are caught and consumed, but less frequently. As the annual sea ice retreats, polar bears throughout their range are forced ashore, where they mostly live off their stored adipose tissue. However, while land-bound they have been observed catching birds and terrestrial mammals. Although polar bears evolved from brown bears (U. arctos), direct observations of polar bears diving for and catching fish have not been reported. Here, we document observations of a young male polar bear catching Arctic charr (Salvelinus alpinus) and Fourhorn sculpin (Myoxocephalus quadricornis) by diving in Creswell Bay, Nunavut. We recorded six search bouts, where six fish were caught during dives, which were preceded by a snorkel. The average dive and snorkel length was (mean ± SD) 13 ± 5 and 6 ± 2 s, respectively.
Keywords
Polar bear Ursus maritimus Fishing behaviour Arctic charr Fourhorn sculpin NunavutNotes
Acknowledgments
Many thanks to the residents of Resolute Bay and S. Akeeagok for sharing their knowledge about where polar bears catch fish in Nunavut. We also appreciate support contributed by Polar Continental Shelf Project (PCSP), Nunavut Arctic College, Northwinds, Leica Germany, and R. Romberg. Comments by K. Rhode and 3 anonymous reviewers were helpful to improve the quality of the manuscript. This is PCSP ÉPCP contribution publication # 019-07. This paper is dedicated to Atsuli, who was MGD’s loyal companion.
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