Stable isotope characterization of community trophic structures in assemblages of aquatic and terrestrial herpetofauna

Abstract

Traditional methods of studying the trophic ecology of herpetofauna are problematic and are under increasing criticism because they may not accurately represent natural systems. The purpose of this study was to assess the utility of stable isotope analyses of carbon and nitrogen to quantify characteristics of trophic structures of natural aquatic and terrestrial assemblages of herpetofauna. Stable isotope analysis was performed on species in herpetofaunal communities in Nova Scotia, Canada. Recurrent patterns in the isotopic data provided quantified observations of potential predator-prey interactions among species, dietary overlap and partitioning, and was useful in estimating the relative trophic position of each species. The results of this study, in addition to providing quantified data of herpetofaunal trophic ecology, validated the application of stable isotope analysis in the study of natural communities. This study provides the basis for quantifying interactions and estimating trophic position of herpetofauna using stable isotope analysis.