| Summary: | Thesis (Master's)--University of Washington, 2019 Wildlife have varying responses to disturbances depending on the duration, severity, and type of disturbance event. Some disturbances modify wildlife habitat, and can impact community assembly and patterns of diversity, while others can modify wildlife behavior. Human disturbance often elicits two opposite behavioral response from wildlife, one in which they can exhibit “fear effects”, where they avoid humans, and the “human shield effect”, where wildlife are attracted to centers of human activity and use human presence as a buffer against predation. However the level of human disturbance that causes a detectable change in wildlife behavior remains unknown. Many disturbances that alter landscapes and modify wildlife habitat are expected to increase in frequency and severity with climate change, and post-disturbance successional patterns of wildlife communities remain poorly understood. In this thesis, I investigated the responses of wildlife to two types of disturbances: human activity (Chapter 1) and glacial recession (Chapter 2) in Glacier Bay National Park, Alaska (GLBA). GLBA is a remote park with relatively low but increasing levels of visitation, and it is centered around a marine fjord that is the product of the most rapid glacial recession in modern times. To understand the responses of brown bears (Ursus arctos), black bears (Ursus americanus), moose (Alces alces), and wolves (Canis lupis) to human activity, I used camera traps to document wildlife activity and a paired-plot, crossover experimental design to manipulate human visitation during summers 2017 and 2018 (n = 5 pairs of sites). Single-season occupancy models and activity overlap analyses indicated that brown bears were unaffected by human use in GLBA, black bears exhibited fear effects temporally but the human shield effect spatially, moose utilized human presence as a shield temporally, and wolves exhibited fear effects temporally. Traditional occupancy models assume logit-linear ...
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