Threading the needle: how humans influence predator-prey spatiotemporal interactions in a multiple-predator system

Perceived predation risk and the resulting antipredator behavior varies across space, time, and predator identity. Communities with multiple predators that interact and differ in their use of space, time of activity, and hunting mode create a complex landscape for prey to avoid predation. Anthropogenic presence and disturbance have the potential to shift interactions among predators and prey and the where and when encounters occur. We examined how spatiotemporal antipredator behavior of white-tailed deer fawns (Odocoileus virginianus) differed along an anthropogenic disturbance gradient that had black bears (Ursus americanus), coyotes (Canis latrans), bobcats (Lynx rufus), and humans present. We quantified 1) coarse-scale spatial co-occurrence in species distributions, 2) temporal overlap across the diel cycle, and 3) fine-scale spatiotemporal associations between humans, bears, coyotes, bobcats, adult male deer, and fawns. We also examined how deer vigilance behavior changed across the anthropogenic disturbance gradient and survey duration. Anthropogenic disturbance influenced spatiotemporal co-occurrence across multiple scales, often increasing spatiotemporal overlap among species. In general, species’ spatial co-occurrence was neutral or positive in anthropogenically disturbed environments. Bears and fawns, coyotes and adult male deer, and bobcats and fawns all had higher temporal overlap in the agriculture-development matrix sites. In addition, factors that influenced deer vigilance (e.g., distance to forest edge and predator relative abundance) in the agriculture-development matrix sites did not in the forest matrix site. By taking into account the different antipredator behaviors that can be detected and the different scales these behaviors might occur, we were able to gain a more comprehensive picture of how humans reduce available niche space for wildlife, creating the neutral and positive spatiotemporal associations between species that studies have been seeing in more disturbed areas.