Hurricanes are a source of major disturbance. They can create changes in community structure and habitat, and are predicted to become more frequent and severe as a result of changing climate. St. John, US Virgin Islands, lies within the Lesser Antillean island chain in the Caribbean. Virgin Islands National Park comprises 60% of the island with at least five habitat types. Prior studies predict eleven reptile and eight amphibian species on the island. The goal of this study was to assess community dynamics after a major disturbance (2017 catastrophic hurricanes Maria and Irma) to determine changes in herpetofaunal distribution patterns by comparing surveys in 2016 and 2018. Visual encounter surveys (VES), audio surveys, and incidental encounters were used. GPS units were used to collect locations of individuals, which were then used to generate species distribution maps using ArcMap.
Results/Conclusions
One notable change from 2016 to 2018 occurred with E. coquí and E. antilliensis. In 2016, E. antilliensis was common across the island, primarily detected through audio surveys in groups of 2-10+. However, in 2018, only three individuals were heard calling in total and only one was visually observed, suggesting a decrease in abundance of this species. E. coqui was not heard or seen during 2016; however, in 2018 individuals were opportunistically observed and heard calling in moist and dry forest, suggesting this species has expanded its range or abundance on the island. H. mabouia also appeared to have extended its range, expanding from only Lameshur Bay to Europa Bay, Brown Bay, and Ram’s Head trail. There were no significant overall differences between habitat use and distributions across the island between 2016 and 2018; however, there is a suggestion of modification of ranges and possibly changes in abundances. This suggests that the island is able to recover quickly from major disturbances and is highly resilient, though the potential exists for other effects that cannot be quantified by our survey techniques. Enhanced surveys could provide a better understanding of population trends of resident species and contribute to the conservation of herpetofauna.