Trophic ecology of the Ocellated LizardLacerta lepidain an arid zone of southern Spain: relationships with availability and daily activity of prey

The diet of the Ocellated LizardLacerta lepidawas studied by means of faecal analysis, during two consecutive summers, in an arid zone of south-east Spain. The analysis of 181 faecal samples revealed 1929 prey items. Coleoptera was consistently the main group in the diet; two beetle species,Ditomus capitoandMorica hybrida, maintained a frequency of around 40% in the diet. Vertebrates and gastropods were scarce, whereas plant food, comprised of fleshy fruits of CaperCapparis spinosaand EphedraEphedra distachya, varied in importance throughout the study period. The lizard diet was also compared with prey availability, estimated by pitfall traps. Selectivity analysis showed strong selection of the lizard upon some groups and systematic rejection of others. Daily activity of the Ocellated Lizard, as well as its diet composition, was studied in relation to daily activity of prey. The lizard diet proved to be based on nocturnal prey, implying active searching for these groups during the day, or a partially crepuscular-nocturnal activity in the lizard, overlapping with prey activity. The lack of diurnal sightings of the lizard throughout the summer favours the second option. The ecological implications of this feeding strategy in arid systems are discussed.