Pressão de predação sobre a lagartixa-de-areia liolaemus lutzae MERTENS, 1938 (Liolaemidae), introduzida experimentalmente na Praia das Neves, Espírito Santo

Abstract

Lutzae Liolaemus is a small lizard from the family Liolaemidae endemic of restingas of Rio de Janeiro, distributing from the restinga of Marambaia to Cabo Frio. It occupies a restricted habitat, the sandy beach, which is very threatened by human pressures, and they drove the species to be inserted in the red list of endangered species. A project of translocation of the species began in 1986, retiring 51 individuals in the restinga of Barra de Marica - RJ and introducing them in Praia das Neves-ES. The project is currently funded by FNMA and one of his goals is to study the relationship between this introduced population and their predators, the main purpose of this work. Estimates were made regarding the predation pressure exerted on the lizard through a consensus model combining the two methods. The first was based on surveys for their potential predators in the study area and the second in the predation experiments using replicas of lizards covered with modeling clay. The work was carried out in three distinct campaingns (August 2008 and August/December 2009), in scrub and beach habitats. Predators of Praia das Neves were very similar to Barra de Marica, their place of origin. We identified 19 species potential predator of lizards, the birds being the most representative with 16 species, among these, the most abundant as well as frequent were Guira guira (cuckoo) and Athene cunicularia (burrowing owl). The major predator of the replicas was the crab O. quadrata, a specie very abundant in the locality, followed by, outnumbered by the birds, the most important in the scrubs. The intensity of attacks on replicas seems to be influenced by the abundance of predators in their habitats, as confirmed by analysis of correlation. Techniques to ordination data, separated the variable distance from the sea as the most important on the dynamics of the experiment. When we consider the birds as the main predators of the sand-dune lizard in Praia das Neves, the pressure seems more intense in the scrubs, over the beach, which may have influenced the establishment of new population in the area and prevented colonization adjacent habitat.