Polar Biology

, Volume 32, Issue 10, pp 1529–1537 | Cite as

Spatial and temporal patterns of problem polar bears in Churchill, Manitoba

  • Lindsay TownsEmail author
  • A. E. Derocher
  • I. Stirling
  • N. J. Lunn
  • D. Hedman
Original Paper


Human–bear interactions near the town of Churchill, Manitoba occur annually because the Western Hudson Bay polar bear population spends 4–5 months on-land each year when the sea ice melts completely. Significant changes have occurred in the Hudson Bay ecosystem and in the bear population as a result of climate warming; however, how these changes may have influenced human–bear interactions near Churchill is unclear. This study examined the temporal and spatial patterns of 1,487 problem bears captured in the Churchill area from 1970 to 2004. We also examined the relationship between problem bears and environmental variables as well as the Nunavut harvest. The number of individual problem bears caught near Churchill varied from 10 to 90 individuals per year and increased over time. Subadult males comprised 39%, subadult females 23%, adult males 18%, females with young 14%, and solitary females 6% of captures. Bears that became problem individuals were in closer proximity to the Churchill area. Nutritional stress and a northward shift in the distribution of the bears that spend the summer on-land in northeastern Manitoba may account for the increase in problem bear numbers. The date of sea ice freeze-up, which is getting progressively later, was the best predictor explaining the annual variation in the occurrence of problem bears. These results provide an understanding of how a warming climate may directly impact polar bear behaviour. This information may allow wildlife managers to predict relative levels of human–bear interactions and thereby implement effective management strategies to improve human safety and the conservation of polar bears.


Ursus maritimus Polar bear Problem bear Churchill Human–bear interactions Harvest Sea ice Distribution Nutritional stress 



Support was provided by ArcticNet, Canadian Wildlife Federation, Churchill Northern Studies Centre, Environment Canada, Manitoba Conservation Sustainable Development Innovations Fund, Natural Sciences and Engineering Research Council, Northern Scientific Training Program of Indian and Northern Affairs Canada, Parks Canada, Nunavut Wildlife Management Board, Polar Continental Shelf Project, World Wildlife Fund Canada, and the University of Alberta. We are grateful for the years of dedicated work by numerous Resource Officers from Manitoba Conservation who contributed to the collection of data. We wish to thank S. Kearney of Manitoba Conservation for providing insights into the Polar Bear Alert Program. Harvest data from Nunavut was kindly provided by the Government of Nunavut, Department of Environment. A. Gagnon, Department of Geography, University of Liverpool kindly assisted with information on sea ice break-up and freeze-up. W. Calvert of Environment Canada provided assistance extracting archived data.


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Lindsay Towns
    • 1
    Email author
  • A. E. Derocher
    • 1
  • I. Stirling
    • 1
    • 2
  • N. J. Lunn
    • 2
  • D. Hedman
    • 3
  1. 1.Department of Biological SciencesUniversity of AlbertaEdmontonCanada
  2. 2.Wildlife Research Division, Science and Technology BranchEnvironment CanadaEdmontonCanada
  3. 3.Manitoba ConservationThompsonCanada

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