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Grizzly bear response to open-pit mining in western Alberta, Canada

  • Author / Creator
    Cristescu, Bogdan
  • Industrial development is transforming Alberta's landscapes, with largely unquantified effects on wildlife species. Open-pit mining is occurring on vast expanses, most notably for bitumen but also extensively for coal in a rich seam that traverses the province. Major concerns have developed over the status of the grizzly bear (Ursus arctos) in relation to this and other industrial developments, contributing to the species' listing as threatened. My objective was to assess how bears respond to mining by using Global Positioning System (GPS) data from radiocollared individuals. Using movement data in a Before-After-Control-Impact design, I found that bears used mined landscapes during and after mining, selecting undisturbed and reclaimed areas over active and inactive ones. Females with cubs had the greatest home range overlap with mines. Males moved shorter distances on/near mines following reclamation. Based on field visitation of GPS clusters I developed a multinomial model to predict bear behavioural state from GPS radiocollar data. The model had good predictive accuracy particularly for ungulate consumption. Predation is an important source of meat for grizzly bears on mined landscapes, with elk (Cervus elaphus) a major component in bear diet following reclamation. Although all ungulates except moose (Alces alces) were more likely to occur on reclaimed mines, bears consumed them primarily outside mined areas, or in undisturbed tree patches on mines. Caching of food was common, especially large-bodied prey. Dietary analysis from scat showed that bears switched their diet from predominantly ungulates in the foothills and Hedysarum spp. roots in the mountains to herbaceous vegetation sown on mines for reclamation. I propose that resting-site selection can be used as an indicator of perceived risk from human ‘predation’, and show that bears select high horizontal cover for resting, bedding more during the day in foothills with high human activity, and at night on reclaimed mines and in protected areas. Because the mines had restrictions on public access, these findings suggest that bears can persist despite landscape change because they are remarkably adaptable to disturbance and food availability. However, risk of mortality is high if bears are not protected from humans, e.g., by using access management.

  • Subjects / Keywords
  • Graduation date
    2013-06
  • Type of Item
    Thesis
  • Degree
    Doctor of Philosophy
  • DOI
    https://doi.org/10.7939/R3K305
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
  • Language
    English
  • Institution
    University of Alberta
  • Degree level
    Doctoral
  • Department
    • Department of Biological Sciences
  • Specialization
    • Ecology
  • Supervisor / co-supervisor and their department(s)
    • Boyce, Mark (Biological Sciences)
  • Examining committee members and their departments
    • Derocher, Andrew (Biological Sciences)
    • Miller, Sterling (National Wildlife Federation)
    • Foote, Lee (Renewable Resources)
    • Lewis, Mark (Biological Sciences)
    • Stenhouse, Gordon (Foothills Research Institute)