Managing wolves ( Canis lupus) to recover threatened woodland caribou ( Rangifer tarandus caribou) in Alberta

Across Canada, woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) populations are declining because of human-induced changes to food webs that are resulting in apparent competition-induced increases in predator-caused caribou mortality. We tested the hypothesis that wolf (Canis lupus L., 17...

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Bibliographic Details
Published in:Canadian Journal of Zoology
Main Authors: Hervieux, Dave, Hebblewhite, Mark, Stepnisky, Dave, Bacon, Michelle, Boutin, Stan
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 2014
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Online Access:http://dx.doi.org/10.1139/cjz-2014-0142
http://www.nrcresearchpress.com/doi/full-xml/10.1139/cjz-2014-0142
http://www.nrcresearchpress.com/doi/pdf/10.1139/cjz-2014-0142
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Summary:Across Canada, woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) populations are declining because of human-induced changes to food webs that are resulting in apparent competition-induced increases in predator-caused caribou mortality. We tested the hypothesis that wolf (Canis lupus L., 1758) population reduction could reverse declines in a woodland caribou population following a BACI (before-after-control-impact) design conducted over a 12-year period in west-central Alberta, Canada. We monitored annual survival for 172 adult female caribou and calf recruitment from 2000 through 2012 and conducted a provincial government delivered wolf population reduction program annually during the winters of 2005–2006 to 2012 (inclusive) in an area centered on the Little Smoky range. Wolf removal translated to a 4.6% increase in mean population growth rate of the Little Smoky population mostly through improvements in calf recruitment. In contrast, the Red Rock Prairie Creek control population exhibited a 4.7% decline. Although the wolf population reduction program appeared to stabilize the Little Smoky population, it did not lead to population increase, however, with λ remaining approximately equal to 1. Therefore, we recommend, if required, predation management be combined with effective habitat conservation and long-term planning to effect the recovery of species, such as woodland caribou, which are declining as a result of habitat-mediated apparent competition.