Airborne Chemical Information and Context-Dependent Post-Strike Foraging Behavior in Pacific Rattlesnakes (Crotalus oreganus)

Abstract

Predators demonstrate context-dependent foraging behaviors to dynamically and successfully track prey and can use multiple cues in this process. In squamate reptiles (snakes and lizards), chemical signals from prey significantly influence predatory behavior, especially substrate and airborne cues. In this study, we examined behavioral variation in rattlesnakes (Crotalus oreganus) during strike-induced chemosensory searching (SICS), a sterotyped complex of behaviors seen in squamates. Rattlesnakes can use both substrate and airborne chemical cues during SICS, but we sought to determine the changes during SICS when either substrate, airborne, or air-deposited chemical cues were the only types available to snakes in a Y-maze. We hypothesize that these cues represent the spectrum of chemical information available in the natural environment. We also modified scoring of choice in the Y-maze by deriving a choice penalty score, a reflection of how extensively the snake explored the unscented arm of the maze. In t...