Climate patterns as predictors of amphibian species richness and indicators of potential stress:

Abstract/Summary

Amphibians occupy a range of habitats throughout the world, but species richness is greatest in regions with moist, warm climates. The objectives of this research were to model the statistical relations of anuran and caudate species richness with mean annual climate for the conterminous U.S., and to compare the strength of these relations at national and regional levels. Model variables were calculated for county and subcounty mapping units, and included 40-year (1960-99) annual mean and mean annual climate statistics, mapping unit average elevation, mapping unit land area, and estimates of anuran and caudate species richness. Climate data were derived from more than 7,500 first-order and cooperative meteorological stations and were interpolated to the mapping units using multiple linear regression models. Anuran and caudate species richness were calculated from the U.S. Geological SurveyNULLs Amphibian Research and Monitoring Initiative (ARMI) National Atlas for Amphibian Distributions. The national multivariate linear regression (MLR) model of anuran species richness had an adjusted coefficient of determination (R2) value of https://0.64 and the national MLR model for caudate species richness had an R2 value of https://0.45. Stratifying the U.S. by coarse-resolution ecological regions provided models for anurans that ranged in R2 values from https://0.15 to https://0.78. Regional models for caudates had R2 values ranging from https://0.27 to https://0.74. In general, regional models for anurans were more strongly influenced by temperature variables, while precipitation variables had a larger influence on caudate models.