PATRONS OF DIVERSITY AND COMPOSITION OF REPTILES IN FRAGMENTS IN THE DRY TROPICAL FOREST IN CORDOBA, COLOMBIA

Tropical dry forest is the most threatened ecosystem around the World and reptiles, as a group, are the least studied of vertebrates. Along 120 transects in six tropical dry forest fragments (between 7 and 84 ha) surrounded by pastures, reptiles were sampled three times during three field seasons using equal day and night efforts. We recorded the highest reptile richness in larger forest fragments but species-area relationship was not apparent when richness estimators predicted more species number in the ensemble. Total abundance and composition in the reptile assemblage did not change along fragment area gradient but larger fragment presented higher number of fragment-exclusive species. The greatest amount of species exchange was between larger and smaller forest fragments. Fragment size clearly affected the lizard Anolis vittigerus but this species is not included in the IUCN threatened categories although habitat loss is the most important factor affecting reptiles' decline. More than 70% of reptiles are rare species (with < 4 individuals) within the ensemble and is important to increase studies of population ecology to identify the response of cryptic species responses to habitat loss and fragmentation.