| Summary: | Thesis (Ph.D.)--University of Washington, 2020 Apex predators can influence ecosystems by changing the density and behavior of herbivores and other predators. As an ecosystem superpredator, humans may also shape top-down effects in ecological communities by altering apex predator abundance and behavior. In many parts of the world, apex predators live in, or are returning to, landscapes that are human dominated. Thus, it is important to understand the ecological role of apex predators in anthropogenic, multi-use landscapes. I used motion-activated camera traps set in a multi-use landscape in northeastern Washington to compare the effects of: 1) wolves (Canis lupus) on spatiotemporal activity patterns of mesopredators and sympatric apex predators; and 2) the effects of hunting and apex predators on the spatiotemporal activity of herbivorous prey. In areas with wolves, other predators used temporal niche partitioning to avoid wolves. Cougars (Puma concolor) and coyotes (Canis latrans) became more active during the daytime, when wolves were least active, which significantly increased their activity overlap with humans. By contrast, bobcats (Lynx rufus) exposed to wolves changed their activity in patterns opposite to coyotes at nighttime and dusk. Although both mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus) increased nocturnality significantly during hunting seasons, the deer species showed species-specific spatiotemporal responses to hunting that, in the case of mule deer, deviated from their typical anti-predator behavior. This pushed mule deer, but not white-tailed deer, into greater spatiotemporal overlap with wolves during hunting seasons, and thus may lead to additive mortality on mule deer from increased wolf predation. In conclusion, the top-down effects of wolves on the behavior of their intraguild competitors appear to be resilient to human disturbance in this system. However, effects on their herbivore prey may be overwhelmed by humans during hunting seasons, leading to ...
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