Richness and distribution of amphibian species in relation to ecological variables in western aegean region of turkey

Abstract

Ecological factors, such as water chemistry variables, regional landscape variables, occurrence of predators, have considerable effects on amphibian distribution and richness. These variables in relation to amphibian species-richness and distribution were investigated by field work studies between February 2006 and August 2008 in freshwater ponds and lakes of Aegean Region, Turkey. Seven amphibian species were observed at the study sites, with mean species richness 4.29±0.34 species per habitat (range= 2 to 6). We used Pearson's correlation coefficients to examine correlations between the variables and to reduce the number of explanatory factors. The data were submitted to a multiple regression analysis at water chemistry and microhabitat scales in order to investigate the most important explanatory factors influencing amphibian species richness and their distribution. According to the results of statistical analysis six regional landscape and nine water chemistry variables were found to be important explanatory factors for amphibian species richness in this region. These results were evaluated and interpreted in term of amphibian conservation and habitat management programs.