Where beavers (Castor canadensis) build: testing the influence of habitat quality, predation risk, and anthropogenic disturbance on colony occurrence

• Main Authors: Mumma, Matthew A, Gillingham, Michael P, Johnson, Chris J., Parker, Katherine L.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: NRC Research Press (a division of Canadian Science Publishing) 2018
• Subjects: British Columbia; Canada; Canis lupus; gray wolf
• Online Access: http://hdl.handle.net/1807/90071; http://www.nrcresearchpress.com/doi/abs/10.1139/cjz-2017-0327

Species distributions are shaped by numerous factors that vary in importance across spatiotemporal scale. Understanding drivers of the distribution of North American beaver (Castor canadensis Kuhl, 1820) is paramount given their profound influence on ecological communities. Our objectives were to evaluate the influence of habitat quality, risk of gray wolf (Canis lupus Linnaeus, 1758) predation, and anthropogenic disturbance on the occurrence of beaver colonies in northeast British Columbia (BC), Canada. We used mixed-effects multinomial logistic regression to model the occurrence of active and inactive colonies, and t-tests to compare landscape covariates associated with active versus inactive colonies. We determined that occurrence of beavers was driven by habitat quality. Occurrence increased in areas with higher vegetation-class richness and greater proportions of open water, nutrient-rich fen, and deciduous swamp. We also observed that active colonies were surrounded by greater amounts of deciduous swamps relative to inactive colonies. We found no evidence that predation risk or industrial activities decreased the occurrence of beavers in northeast BC; although, numerical changes in abundance might occur without changes in distribution. This research illuminated drivers of beaver distribution, while providing a means to predict the occurrence of a keystone species in the boreal ecosystem. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author.