From fear to feast: Rattlesnakes navigate the landscape of fear to optimize foraging

According to optimal foraging theory, mesopredators should forage in areas
where their prey is abundant while avoiding high predation risk. Here, we
investigate how environmental factors influence mesopredators’ abilities
to minimize spatiotemporal overlap with predators while increasing
spatiotemporal overlap with prey. We paired 30 western diamond-backed
rattlesnake (Crotalus atrox) 3D-printed replicas with game cameras in West
Texas for two years to quantify several spatiotemporal factors affecting
prey availability and predation risk. Concurrently, 25 Crotalus atrox were
radiotracked at the same site to gather activity and microhabitat
selection data regarding free-ranging individuals. Random forest
algorithms were trained using data obtained from the game camera and
applied to predict the probability of predation and the probability of
prey encounter for each radiotracking event. Time of day, month,
vegetation structure, and concealment percentage all had a significant
association with the probability of predation and the probability of prey
encounter. Our results suggest that rattlesnakes choose to be active when
and where the probability of prey encounter is significantly higher than
the probability of predator encounter, thus following optimal foraging
theory. Our results demonstrate that mesopredators increase the chances of
prey capture while reducing predator detection in natural settings.