Size-based variation in antipredator behavior within a snake (Agkistrodon piscivorus) population

Variation in an animal's response to a predator likely reflectsthe complex interaction of factors that influence predationrisk. Due to their high degree of behavioral variation and simplifiedbauplan, snakes offer a unique model for investigating the influenceof sex and body size on antipredator behavior. We examined variationin antipredator behavior within a cottonmouth (Agkistrodon piscivorusleucostoma) population. Behavioral responses to human-inducedpredation risk were compared across a continuous scale of bodysize. Defensive responses significantly declined with increasingbody size. After controlling for body size, no differences betweenthe sexes were detected. Although this study suggests that variationin antipredator behavior is, in part, related to body size,some studies on snakes have not found this relationship. Likewise,some studies have demonstrated differences between sexes. Suchdisparate patterns of variation indicate a need for future comparativestudies examining the complex interaction of factors that mayinfluence predator–prey relationships.