Abstract
Human activities are transforming ecosystems worldwide, altering animal behavior, space use, and community composition. In this dissertation, I explore how human disturbances modify large mammal ecology in the southern interior of British Columbia, Canada, with an emphasis on the focal species, mule deer (Odocoileus hemionus). I focus on three core mechanisms of human disturbance effects: disruptions to daily activity and weekly habitat use of animals, and community composition filtering across disturbance gradients. In Chapter 1, I introduce the concept of ecological “time traps,” an extension of ecological trap theory, where human activities induce prey to shift activity into riskier time periods and increase predation risk. Using time-stamped camera trap data, I show that mule deer increased nocturnality in response to road density during summer and to high weekly human use during winter––in both cases increasing temporal overlap with their primary predator, cougars (Puma concolor). In Chapter 2, I evaluate the seasonal drivers of mule deer weekly habitat use by applying structural equation models to camera trap detection data. I disentangle top-down (predation risk) and bottom-up (resource availability, competition) processes, finding that bottom-up and environmental factors overwhelmingly dominate mule deer occurrence patterns—particularly during winter when spatial and nutritional constraints intensify. In Chapter 3, I test predictions of the disturbance–generalist and trophic defaunation hypotheses by modeling community composition responses across human disturbance gradients. I find that road density and human use alter community composition in predictable ways, favoring disturbance-adapted generalists such as coyotes (Canis latrans) and white-tailed deer (Odocoileus virginianus) over larger-bodied, higher trophic-level, or more specialized species like black bears (Ursus americanus), moose (Alces alces), and mule deer. Together, these studies advance understanding of the temporal, spatial, and community-level consequences of human disturbance, introduce the concept of time traps as a new form of ecological trap, and highlight the need to consider species interactions and community dimensions when assessing human impacts on wildlife.