Species Distribution and Habitat Suitability Modeling (SDM/HSM) to Investigate Ecology, Movement, and Distribution of Jefferson Salamander (Ambystoma jeffersonianum) for Potential Vernal Pool Creation

Jefferson Salamanders (Ambystoma jeffersonianum) represent a unique and ecologically significant species whose populations face mounting challenges due to habitat loss, climate change, and a lack of data on their distribution and abundance. This thesis research investigated how Jefferson Salamander distribution in Virginia has changed, identified the extent and location of suitable habitats, and determined potential areas within those habitats for future vernal pool creation. Species Distribution Models (SDMs) and Habitat Suitability Models (HSMs) were employed to predict and assess their distribution and to identify critical habitats, using occurrence data from sources such as the Global Biodiversity Information Facility (GBIF), iNaturalist and data from the Virginia Master Naturalist Program’s vernal pool monitoring program in relation to environmental variables key to both salamander biology and ecology. Analyses revealed that in Virginia, the Blue Ridge and Valley and Ridge regions offer the most suitable habitats for Jefferson Salamanders. However, historical data comparisons show that recent distribution records may represent a range contraction of 40–67%, likely due to habitat modification particularly in northern and western parts of this species’ range. Citizen science data from the Virginia Master Naturalist Program further supported the study, revealing localized habitat preferences within vernal pool ecosystems, phenology and co-occurrence with other vernal pool inhabitants. Findings underscored the necessity of conserving vernal pools and surrounding forest habitats to ensure the species' survival. This research provided actionable insights for habitat restoration and vernal pool creation, supporting the conservation of Jefferson Salamanders and broader amphibian biodiversity. Ultimately, this study helps bridge knowledge gaps and informs efforts to preserve these increasingly rare vernal pool inhabitants.