Holbrook, Joshua D.

Purpose: To quantify Reptile and Amphibian community assemblages in freshwater
wetlands and determine biotic and abiotic factors e.g., wetland permanence and presence of large
fish that may influence assemblage structure. Methods: Wetland Reptile and Amphibians were
monitored via passive trapping at 20 wetland sites at Jonathan Dickinson State Park JDSP in
Hobe Sound, FL. Trapping at JDSP occurred over a single wet season June-November period
and community assemblages were analyzed statistically using multivariate techniques. Results:
Hierarchical clustering revealed two primary assemblages, which included 70 of wetlands. One
assemblage, typical in wetlands containing large-bodied fish, consisted of two or three snake
species and low abundances of anurans in the family Ranidae. The second assemblage, typical of
fishless wetlands, generally had abundant anurans in the families Hylidae and Ranidae.
Conclusion: Though distance from other wetlands as well as wetland permanence also influenced
assemblage structure, fish presence/absence was a larger determinant of herpetofaunal
communities.

Many herpetofaunal species are imperiled, and the causes of this are often a
synergy of multiple factors. In wetlands specifically, two of the possible determinants of
species occurrence and faunal community assemblage are fish presence and wetland
permanence, which are not always correlated. Twenty wetlands were sampled in
Jonathan Dickinson State Park, Florida, USA to observe how wetland herpetofaunal
communities vary with fish, wetland permanence and other environmental factors.
Herpetofaunal communities with and without fish were significantly different from one
another and differences between herpetofaunal communities were primarily due to the
contribution of four species of frogs, two generalist ranids and two specialist hylids.
Wetland permanence had no observable effect on community structure. Fishless wetlands were significantly more species-rich and possessed higher numbers of individuals even for species that occurred in both fishless and fish wetlands, regardless of their permanence. These findings have implications for wetlands restoration and herpetofaunal conservation.