Testing the predatory behaviour of Podarcis sicula (Reptilia: Lacertidae) towards aposematic and non-aposematic preys

AbstractFood preferences and the effects of prey chemical repellents in the dietary behaviour of Podarcis sicula were tested using four species of Carabid beetles as prey models. The goal of the study was to assess (i) the ability of P. sicula to recognize insect preys provided with chemical repellents and aposematic colorations under laboratory conditions, and (ii) the importance of chemical signals used by the prey model as antipredatory strategy. Preys used in this study were Brachinus sclopeta and Anchomenus dorsalis (aposematic species) and Amara anthobia and A. aenea (non-aposematic species). Aposematic species are characterized by warning color pattern and by production of chemical repellents, while non-aposematic ones do not. Amara anthobia and A. aenea were attacked with high frequency by P. sicula, Brachinus sclopeta and Anchomenus dorsalis with low frequency. Non-aposematic species were preyed more often than the aposematic ones. Brachinus sclopeta was preyed after low latency, while Amara anthobia and A. aenea after long latency. Non-aposematic species were captured and eaten without difficulty, while when B. sclopeta or A. dorsalis were captured, lizards always tossed their head and then rub the snout on the soil, probably because of the unpalatability of aposematic preys.