Landscape and hydrologic effects on anuran species in the Florida Everglades at multiple spatial scales

Background/Question/Methods: The Comprehensive Everglades Restoration Project (CERP) is underway across much of central and south Florida. The extensive projects associated with this restoration effort will affect the distribution and abundance of organisms across the landscape. Understanding how species are influenced by factors operating across spatial scales is an important step in monitoring the effects of ecosystem restoration on species, and assessing the success of CERP. We used generalized linear models to examine the occurrence and richness of anuran species in relation to hydroperiod and landscape variables across three spatial scales (200m, 500m, and 1000m) in Big Cypress National Preserve and Everglades National Park. 

Results/Conclusions: Species richness and presence was positively associated with edge density and habitat diversity on all scales. Edge density was an important variable in the model sets. Hydroperiod was not as important in most of the models, and was somewhat negatively associated with anuran species richness and presence on all scales. The largest scale, 1000m, was best for describing species richness and presence, aside from Eastern Narrowmouth Toad (Gastrophryne carolinensis). Presence of G. carolinensis was described best by variables at the 500m scale. Our results indicate that taking into account multiple scales, especially those at the intermediate and landscape scales is useful when looking at the effects of habitat and hydrologic changes on anurans.