Distribution of tadpoles of large wrinkled frog <i>Nyctibatrachus major</i> in central Western Ghats: influence of habitat variables

Abstract

The relationship between habitat variables and the distribution and abundance of adults and tadpoles of Nyctibatrachus major (large wrinkled frog) in 35 forest streams in central Western Ghats is detailed in this paper. Tadpoles were not equally distributed among these streams. Adult frogs and tadpoles were absent from 19 streams. In the remaining 16 streams, adults were found throughout the study period but the density of tadpoles varied considerably. Analysis of habitat variables at streams showed significant relationship with canopy cover over the streams, presence of leaf litter and high relative humidity on the occurrence of tadpoles. Reduction in canopy cover increases light level and air and water temperature of the streams discouraging the occurrence of adult frogs and tadpoles. However, canopy cover in the study area is frequently altered by agriculture related human activities including removal of trees for fuel and timber, pruning of green leaves and twigs for making manure and conversion of forest into commercial plantations. The results suggest that disturbances to forest canopy near streams could have deleterious effects on the occurrence and distribution of tadpoles.