Assemblage and Diversity of Anurans in Two Forests of the Western Ghats

Abstract

The Western Ghats of India being a hotspot of biodiversity, amphibian population deserves precise and systematic exploration. In the present study, we evaluated the pattern of occurrence of anurans (during monsoon, post-monsoon and summer) in two forest ecosystems (evergreen and semi-evergreen) of the Western Ghats of Karnataka. Abiotic factors (air/water/soil temperature, humidity, illumination, canopy cover and litter thickness) in the forests chosen were assessed. The frequency of occurrence, diversity, evenness and expected number of species of anurans were calculated by standard methods. A total of 22 and 15 species of anurans was recorded in the evergreen and semi-evergreen forests, respectively. Species richness and diversity were higher in the evergreen forest than semi-evergreen forest. The diversity of anurans was higher during wet seasons (monsoon and post-monsoon) than dry season (summer). The rarefaction indices also revealed higher expected number of species during monsoon and or post-monsoon seasons than summer season. The anuran population composed of widespread, endemic and endangered species. The most frequent species of anurans recorded in this study include Clinotarsus curtipes, Duttaphrynus melanostictus, Euphlyctis cyanophlyctis, Fejervarya sahyadris, Hoplobatrachus tigerinus and Sylvirana temporalis. Among the anuran assemblage, Fejervarya sahyadris, Pseudophilautus wynaadensis, Raorchestes charius and Rhacophorus lateralis have been considered as the endangered species. The present study constitutes a baseline data on the anurans of Western Ghats of Karnataka.