A cross-site comparison reveals limited geographic variation in risk avoidance of snowshoe hares

Predation risk induces a myriad of behavioral antipredator responses of prey. However, different antipredator behaviors exhibit different degrees of flexibility within a single prey species. Moreover, how predator species composition and traits interact with the flexibility of particular antipredator behaviors to determine spatiotemporal activity patterns of prey remains unknown. We examined geographic variation in multiple behavioral axes of a single prey species, snowshoe hares Lepus americanus, across three different ecosystems in northern North America that differed in the predator guild (Wisconsin, USA, with multiple generalist predators; Isle Royale, Michigan, USA, with a single generalist predator; and Yukon, Canada, with a specialist ambush predator and a generalist predator). We hypothesized that predator species composition and traits would drive divergent behavioral patterns of hares across ecosystems. Using a biologging-based dataset of hare behaviors and a camera-based dataset of predator occurrence collected over multiple winters, we examined diel activity patterns, space use, and movement of hares while accounting for variable environmental conditions. Hares were only slightly less nocturnal (<10%) when faced with a single nocturnal generalist predator (Isle Royale), and they exhibited highly comparable diel activity patterns across all sites. Patterns of spatial risk avoidance of hares were moderately different between the multi-predator systems; hares potentially avoided more lethal predators in Wisconsin and exhibited the opposite patterns of habitat use between daytime and nighttime in Yukon, possibly to avoid the most active predator at each time of day. Additionally, hare movements were shorter and more tortuous where ambush specialist predators were present (Yukon). Our study demonstrates that spatiotemporal risk avoidance of prey can exhibit limited geographic variation, but certain behavioral responses, such as diel activity, may be more conserved across ecosystems.