Non-native species dominate herpetofaunal community patterns in both native and non-native habitat patches in urban Miami-Dade County

Abstract

Land use change and invasive species are two of the leading causes of native biodiversity loss, yet our understanding of how these interact in urban centers is limited. In South Florida (USA), urbanization and increased anthropogenic pressure has led to massive land conversion and species introductions. South Florida has the largest number of established non-native reptile and amphibian species in the world, while detection of many native species has decreased. Native species may be adapted to the unique and rare habitats of South Florida such as the pine rocklands, which have been reduced to 2% of their original extent. We conducted surveys for reptiles and amphibians in 15 pairs of native/non-native parks to examine the interaction between habitat modification and herpetofaunal invasion. Less than 10% of the individuals recorded were native, and we found no difference in the relative abundance or richness of native species between native and non-native parks. Community analyses indicate that only 9% of the total variance in herpetofaunal community composition is between native and non-native parks, and that even this difference is driven by non-native species. The brahminy blind snake (Ramphotyphlops braminus), the most widely introduced snake species in the world, is the best indicator of native habitat patches, and two invasive lizards from the Caribbean (Anolis sagrei and A. equestris) are the best indicators of non-native habitat. These results demonstrate that non-native reptiles and amphibians dominate both non-native and native habitat patches in Miami-Dade County.