Diversity and distribution of amphibians and reptiles in the Caramoan Island Group, Maqueda Channel, Southern Luzon, Philippines

Abstract

We report for the first time the herpetological biodiversity (amphibians and reptiles) of the Caramoan Island Group (CIG), Maqueda Channel, southern Luzon Island, the Philippines. Herpetofaunal biodiversity assessment, using the standard field-based methodology for survey work, was conducted at nine sites in the CIG, off the northeast coast of the Bicol Peninsula of southern Luzon. The overall species richness (s) in the CIG is 22 (three amphibians, 12 lizards, and seven snakes) represent new island records for a variety of the native species, ten of which are endemic to the Philippines. Beta diversity (β-diversity) of the CIG is 0.84 reflecting a relatively high degree of local area turnover of species when among-site comparisons were quantified; this finding most likely reflects habitat variability which is consistent with our observation emphasizing how a high proportion of faunal diversity is associated with, or confined, to very specific microhabitats (limestone areas, lower-montane forests, mangroves, beach coastal forests, etc.). The overall community similarity index of the archipelago was 0.545 implying that CIG has moderate overlap of amphibian and reptilian species composition. Our findings provide baseline information on the unique composition of herpetofauna in the CIG, which highlights a general paucity of knowledge about the Peninsula’s herpetofaunal diversity.