Effects of Earlier Sea Ice Breakup on Survival and Population Size of Polar Bears in Western Hudson Bay

@inproceedings{Regehr2007EffectsOE,
  title={Effects of Earlier Sea Ice Breakup on Survival and Population Size of Polar Bears in Western Hudson Bay},
  author={Eric V. Regehr and Nicholas J. Lunn and Steven C. Amstrup and Ian Stirling},
  year={2007}
}
Abstract Some of the most pronounced ecological responses to climatic warming are expected to occur in polar marine regions, where temperature increases have been the greatest and sea ice provides a sensitive mechanism by which climatic conditions affect sympagic (i.e., with ice) species. Population-level effects of climatic change, however, remain difficult to quantify. We used a flexible extension of Cormack–Jolly–Seber capture–recapture models to estimate population size and survival for… Expand
Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline.
TLDR
Investigation of the population dynamics of polar bears in the southern Beaufort Sea from 2001 to 2010 suggests that factors other than sea ice can influence survival, and refined understanding of the ecological mechanisms underlying polar bear population dynamics is necessary. Expand
Demography of an apex predator at the edge of its range: impacts of changing sea ice on polar bears in Hudson Bay.
TLDR
It is found that survival of female polar bears was related to the annual timing of sea ice break-up and formation, and this support previous evidence for a demographic linkage between sea ice conditions and polar bear population dynamics. Expand
Polar bear population status in the northern Beaufort Sea, Canada, 1971-2006.
TLDR
The NB polar bear population appears to have been stable or possibly increasing slightly during the period of this study, which suggests that ice conditions have remained suitable and similar for feeding in summer and fall during most years and that the traditional and legal Inuvialuit harvest has not exceeded sustainable levels. Expand
Survival and breeding of polar bears in the southern Beaufort Sea in relation to sea ice.
TLDR
The effects of sea ice loss on polar bears in the southern Beaufort Sea may apply to polar bear populations in other portions of the polar basin that have similar sea ice dynamics and have experienced similar, or more severe, sea ice declines. Expand
Effects of climate warming on polar bears: a review of the evidence.
TLDR
Evidence that documents how loss of sea ice negatively affects polar bears' long-term survival is summarized, with quantifiable negative effects being documented first in the more southerly subpopulations, such as those in Hudson Bay or the southern Beaufort Sea. Expand
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TLDR
Home range size was predicted by season, ice break-up date, and individual in a multiple regression, though R2 was low, and solitary females had smaller home ranges and were closer to land compared to females with offspring. Expand
Shifts in female polar bear (Ursus maritimus) habitat use in East Greenland
TLDR
Results indicate that multi-decadal loss of sea ice has resulted in shifts in polar bear habitat use in EG, and there was a statistically significant and stronger winter preference in the 2000s for adult females to select for higher sea ice concentrations. Expand
Future sea ice conditions in Western Hudson Bay and consequences for polar bears in the 21st century.
TLDR
This work predicts changes in the ice cycle and the sea ice concentration in spring with a high-resolution sea ice-ocean model and warming forced with 21st century IPCC greenhouse gas (GHG) emission scenarios: B1 (low), A1B (medium), and A2 (high). Expand
Population ecology of polar bears in Davis Strait, Canada and Greenland
Until recently, the sea ice habitat of polar bears was understood to be variable, but environ- mental variability was considered to be cyclic or random, rather than progressive. Harvested populationsExpand
Transient benefits of climate change for a high-Arctic polar bear (Ursus maritimus) subpopulation.
TLDR
Evidence is provided for range expansion, improved body condition, and stable reproductive performance in the KB polar bear subpopulation, together with a likely increasing subpopulation abundance, which may reflect the shift from thick, multiyear ice to thinner, seasonal ice with higher biological productivity. Expand
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