Use of Predator Chemical Cues by Three Species of Lacertid Lizards (Lacerta bedriagae, Podarcis tiliguerta, and Podarcis sicula)

Abstract

Three species of lacertid lizards (Lacerta bedriagae, Podarcis tiliguerta, and Podarcis sicula) are able to detect the former presence of the saurophagous snake Coluber viridiflavus by tongue flicking. Lizards tongue flicked more in cages previously inhabited by the predatory snake than in clean cages or in cages treated with eau-de-cologne. They also exhibited behavioral acts typically associated with stressful situations (foot shakes, tail vibrations, starts) more frequently when predator chemicals are present Individ- uals from the two Podarcis species that came from populations syntopic with C. viridiflavus were also able to distinguish between chemical cues from this saurophagous predator and a nonsaurophagous snake (Natrix maura). In these lizards, the former presence of N. maura did not elicit higher tongue-flick rates or stress- indicating behaviors. In contrast, individuals of Lacerta bedriagae collected from a snake-free area increased tongue-flick rate and frequency of stress-related behavior in response to chemicals of both snakes, suggesting that prior contact is not required for chemosensory recognition of snakes in this species but may facilitate the distinction between different species of snakes. The presence of predator (C. viridiflavus) chemical cues induces a shift in the microhabitat use of the lizard species studied. In a large terrarium containing various substrates, lizards chose different types of microhabitats when chemical cues of C. viridiflavus were present than when absent and avoided the side of the terrarium labeled with the chemicals.