Local and Landscape Drivers of Amphibian Community Composition across Illinois

Amphibian community composition is influenced by local habitat conditions and landscape features, however, identifying what factors drive shifts in amphibian communities is often difficult. Accurate collection of community and habitat data is difficult and inherent correlation within and among community and habitat factorscomplicates analyses and the interpretation of results. To determine the major drivers of amphibian assemblages in Illinois, our study utilized an occupancy and detectability sampling scheme for larval and adult amphibian presence at 252 ponds throughout the state to identify local and landscape features driving amphibian communities across the state. For each pond, local habitat variables (e.g. presence of fish) were measured in situ and landscape scale variables (e.g. percent forest within a buffer) were determined using lidar derivatives and aerial photography (both from public sources). We used a multivariate approach to determine what factors shaped amphibian communities and which species were associated with shifts in community composition. After controlling for geographic location (latitude and longitude), the presence of forest and agriculture on the landscape, as well as the presence of fish were major drivers of amphibian community composition. Ultimately, our results provide quantitative evidence of the factors shaping amphibian communities across the landscape and identified the species most affected.