UBC Theses and Dissertations
First year site fidelity and survival in reintroduced captive-bred Vancouver Island marmots (Marmota vancouverensis) Jackson, Cheyney L.
The Vancouver Island marmot is a critically endangered sciurid endemic to British Columbia, Canada. By 1997, the species had collapsed to fewer than 150 individuals in total. Between 2003 and 2010, 301 captive-bred marmots were implanted with radiotelemetry transmitters and released to new sites and extinct colonies to supplement the wild population. I evaluated reintroduction success based on three short-term measures: first season fidelity to release site, active season survival from release to hibernation, and overwinter survival through early spring. I used generalized linear mixed models to evaluate the influence of sex and age, release practices and procedures, and the local and landscape-level attributes of release habitats on site fidelity and survival. Results suggested that poor overwinter survival has been the limiting factor in first-year reintroduction success. In all years, overwinter survival was lower for newly released captive-bred marmots than for their wild or previously-released counterparts. Release date was the variable most predictive of success, but was positively associated to site fidelity and active season survival and negatively associated to overwinter survival. Release date was the only predictor for overwinter survival, whereas site fidelity was also negatively impacted by the presence of resident females at the release site. Active season survival was highest for females, 2-year olds, and marmots released to sites with talus. I discuss these results in the context of current release practices for Vancouver Island marmots, and make recommendations for future release candidates, site characteristics, and release procedures.
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Attribution-NonCommercial-NoDerivatives 4.0 International