| Summary: | Degree: Master of Science Abstract: There is evidence that prey can perceive the risk of predation, and may alter habitat selection, increase vigilance, alter social grouping, and reduce migratory behaviour in response. Previous approaches that quantify predation risk have focused on measuring the different phases of predation such as predator space use or predator kill sites; data which can be costly to accumulate and often results in low sample sizes. We used a non-invasive alternative using predator scats to assess summer predation risk to different migratory herds segments of the partially migratory elk (Cervus elaphus) herd in Ya Ha Tinda, Alberta, Canada. Elk predation risk was estimated by combining the summer distribution of bears, wolves, coyotes and cougars (Ursus arctos/U. americanus, Canis lupus, C. latrans and Puma concolor, n = 476) predicted from scat-based resource selection functions and presence of elk in the scat. Scat contents were analysed using macroscopic and DNA analysis methods to detect the presence of elk in scats. Multivariate analysis revealed high overlap in scat contents across predators with bear scats containing more vegetation and coyote scats containing more small mammals. Elk occurred more frequently in wolf and bear scats found where resident elk summered near the Ya Ha Tinda and elk occurrence was associated with areas with high herbaceous forage biomass and amount of open habitat. Elk occurred more frequently in cougar scats found on the range of the eastern migrants, where forest edge density was high. Overall, elk who migrated westward into Banff National Park were exposed to lower wolf, cougar and bear predation risk than resident elk and eastern migrants. Specialization: Ecology
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