Do Bufonids Employ Different Anti-Predator Behaviors Than Ranids? Comparison among Three European Anurans

Abstract

European anurans are prey for a variety of predators, against which they have evolved a range of defense behaviors. We investigated defensive behaviors of three European anurans: the Common Toad (Bufo bufo), the Common Frog (Rana temporaria), and the Edible Frog (Pelophylax esculentus) during interactions with a predator (hedgehog) and a control stimulus (rabbit). We hypothesized that (H1) due to small capacity to flee quickly from a predator, B. bufo has evolved a more diverse repertoire of behavioral defenses than the ranids, R. temporaria and P. esculentus. We also hypothesized that (H2) B. bufo can minimize the secretion of metabolically costly poison through behavioral control. According to our predictions, the repertoire of defensive behaviors was more complex in B. bufo than in the ranids. Also, the number of threatening behaviors was higher in toads than in both frog species. Fleeing was the most common response employed by all tested anurans. We report a new anti-predator behavior in the Common Toad: head hitting. As B. bufo released the poison only after squeezing of parotoid macroglands by the predator, we conclude that the Common Toad can minimize poison release through behavioral control. Our data suggest that length of hind-legs and, related to this, mode of locomotion (jumping vs. hopping) can affect anti-predator behavior in anurans.