The Herpetological Journal

pp.27-32

Authors: José Martín, Pilar López And Andrés Barbosa

Abstract: Morphological adaptations ofamphisbaenians to fossorial life may affect their anti-predator behaviour and escape decisions. Amphisbaenians exposed on the soil surface by a predator may decide to escape either by burrowing immediately or by using alternative defensive behaviours. This decision may depend on the internal state (body temperature and associated burrowing performance) but, because anti-predator behaviours may be costly, an optimal response should also be sensitive to risk and vary according to the threat of predator attack. In a laboratory experiment we simulated predatory attack on individual amphisbaenians of the species Blanus cinereus, and specifically examined the effects of temperature (warm vs. cold) and predation threat (low vs. high) on escape decisions. Amphisbaenians showed significantly longer episodes of an alternative anti-predator behaviour on the soil surface (coiling) when the predation threat was high and when the temperature was low. The time to burrow until half of the body was buried was significantly longer when the temperature was low and was significantly shorter when the threat was high. The variations observed in anti-predator behaviours may reflect the choice of the optimal response under each circumstance, taking into account the estimated predation risk, which is dependent on the characteristics of the initial attack, and potential burrowing performance, which is dependent on body temperature.

Keywords: predation, escape behaviour, fossorial reptile, Blanus cinereus