Interaction between calls and scents in lizard antipredator behavior

LABRA, A; RUIZ MONACHESI M.R.

Murnau, Bavary

Congreso; XXV INTERNATIONAL BIOACOUSTIC CONGRESS; 2015

INTERNATIONAL BIOACOUSTIC

Abstract: Distress calls are vocalizations produced by individuals when they are trapped by a predator. They may enhance the survival probabilities of the caught individual and/or of its conspecifics. The weeping lizard, Liolaemus chiliensis, emits distress calls that seem to benefit conspecifics as they react to these calls, specifically to simple down-modulated, with prolonged immobility, a behavior that would reduce their probabilities of being detected by the predator. This behavior has been recorded when lizards are confronted with distress calls. This lizard, however, emits a wide variety of distress calls, including complex calls with different types of non-linear phenomena. It has been proposed that these nonlinear sounds can honestly communicate fear, and if so, it is expected that alarmed lizards exhibit a stronger antipredator response when they are exposed to complex distress calls. We tested this hypothesis exposing individuals to simple and complex distress calls; the latter contained chaotic noise. In addition, and considering that evidence suggest that adults tend to live in pairs, we tested if the chemical environment, in this case, substrates with scents of the tested individual or from a conspecific of a different sex, may modulate the receiver response. There was an interplay between the type of calls and the chemical environment; individuals reacted with longer immobility after complex than simple calls, but when they were with their own scents (i.e. the own territory). When exposed to scents of a conspecific of a different sex, complex calls determined a shorter immobility than simple calls. These results suggest that the weeping lizard discriminates between simple and complex distress calls, but the triggered antipredator response is modulated by ?where? lizards perceived the risk; a fearful call in the own territory is riskier.