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Polar Biology

, Volume 31, Issue 4, pp 491–499 | Cite as

Population parameters and harvest risks for polar bears (Ursus maritimus) of Kane Basin, Canada and Greenland

  • Mitchell K. Taylor
  • Jeff Laake
  • Philip D. McLoughlin
  • H. Dean Cluff
  • Erik W. Born
  • Aqqalu Rosing-Asvid
  • François Messier
Original Paper

Abstract

We estimated demographic parameters and current harvest risks for a population of polar bears (Ursus maritimus Phipps) inhabiting northern Smith Sound and Kane Basin, Canada and Greenland. Our demographic analysis included a detailed assessment of age- and sex-specific survival and recruitment from 141 marked polar bears, using information contained within the standing age distribution of captures and mark-recapture analysis. Total survival rates \( (\ifmmode\expandafter\bar\else\expandafter\=\fi{x} \pm 1\;{\text{SE}}) \) for females were: 0.374 ± 0.180 (cubs), 0.686 ± 0.157 (ages 1–4), and 0.967 ± 0.043 (ages 5+). Mean litter size was 1.67 ± 0.08 cubs. Females did not reproduce until at least age 6, which is late compared to other populations of polar bears. The model-averaged, mark–recapture estimate of mean abundance (±1 SE) for years 1994–1997 was 164 ± 35 bears. We incorporated demographic parameters and their variances into a harvest risk analysis (i.e., a stochastic, harvested population viability analysis, PVA). Results suggest that polar bears in the region were severely over-harvested during the mark–recapture interval (1992–1997). The current status of the population is unknown.

Keywords

Demography Harvest Mark–recapture Polar bear Population viability analysis (PVA) Program MARK Program RISKMAN 

Notes

Acknowledgments

This work was funded by the Government of Nunavut, the Greenland Institute of Natural Resources, the Polar Continental Shelf Project, the University of Saskatchewan, and the U.S. National Marine Mammal Laboratory. Hunters and trappers of Grise Fiord contributed their knowledge of polar bears in the Kane Basin area. M. Kuc was the primary programmer for RISKMAN and contributed to the development of its algorithms.

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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Mitchell K. Taylor
    • 1
  • Jeff Laake
    • 2
  • Philip D. McLoughlin
    • 3
  • H. Dean Cluff
    • 4
  • Erik W. Born
    • 5
  • Aqqalu Rosing-Asvid
    • 5
  • François Messier
    • 3
  1. 1.Department of the EnvironmentGovernment of NunavutIgloolikCanada
  2. 2.National Marine Mammal LaboratoryAlaska Fisheries Science Center, National Marine Fisheries ServiceSeattleUSA
  3. 3.Department of BiologyUniversity of SaskatchewanSaskatoonCanada
  4. 4.Department of ResourcesWildlife, and Economic Development, Government of the Northwest TerritoriesYellowknifeCanada
  5. 5.Greenland Institute of Natural ResourcesNuukGreenland

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