Global Ecology and Conservation (Sep 2024)
Anthropogenic activities influence spatiotemporal patterns of predator-prey interactions
Abstract
The non-consumptive effects of predator-prey interactions are well-known for their ability to impact ecosystem structure and function. As anthropogenic pressures increase worldwide, it is essential to understand how they influence the non-consumptive effects of predator-prey interactions. Two anthropogenic activities that occur worldwide, hunting and livestock grazing, are known to impact the activity and space use of individual species. However, their effects on predator-prey interactions remain less understood. We evaluated how cattle and human hunting activities influenced the spatial and temporal overlap of five predator (black bear [Ursus americanus], bobcat [Lynx rufus], cougar [Puma concolor], coyote [Canis latrans], and gray wolf [C. lupus]) and four ungulate prey species (elk [Cervus canadensis], moose [Alces alces], mule deer [Odocoileus hemionus], and white-tailed deer [O. virginianus]) in Washington, USA, from 2018 – 2020. We used data from a large-scale camera trap study to test our hypotheses that anthropogenic activities influence spatiotemporal overlap of predators and prey depending on whether they avoid disturbance and risk or are attracted to potential food subsidies. We found cattle and hunter activity influenced species-specific occurrence and activity patterns but had more limited effects on predator-prey overlap. Namely, mesopredators and deer were generally more likely to use areas with cattle activity whereas cougars avoided cattle in the absence of wild prey. Predators and moose used areas with greater hunter activity, possibly creating a human shield for other ungulates where hunter activity was lower. Finally, most species moderately shifted their daily activity patterns in response to cattle and hunter activity. The resulting spatiotemporal patterns were only partially consistent with our expectations owing to the diverse and nuanced responses of predators and prey to cattle and hunter activity. Anthropogenic activities may help reduce predation risk under certain circumstances but do not necessarily create a human shield, underscoring the importance of considering anthropogenic effects on predator-prey interactions.
