FROM FEAR TO FEAST: RATTLESNAKES NAVIGATE THE LANDSCAPE OF FEAR TO OPTIMIZE FORAGING

Abstract

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 thirty 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 was significantly higher than the probability of detection by predators, thus following optimal foraging theory. Our results demonstrate that mesopredators increase chances of prey capture while reducing predator detection in natural setting.