Impacts of Wildfire Burn Severity on Plethodontid Salamander Populations of Great Smoky Mountains National Park.

Wildfire is an increasingly common disturbance in forested landscapes that can drastically alter local habitats. Under current climate change predictions, wildfires are likely to become more frequent and severe. In regions and ecosystems that have historically infrequent fire return intervals, there is little known about how organisms will respond to the more severe and frequent wildfires predicted under climate change. In the southern Appalachian Mountains, USA, fire has been suppressed and severe burns are historically uncommon. This region boasts immense biodiversity and is considered a biological hot spot for diversity in the salamander family Plethodontidae. These species rely upon cool, moist microclimates that may be impacted more by severe fire than by low-intensity wild or prescribed fire. In 2016, the Chimney Tops Two wildfire burned >6000 ha of Great Smoky Mountains National Park, USA, and left a mosaic of burn severity across the landscape. This presented an opportunity to examine how five plethodontid salamander species respond to and recover from a range of burn severity. Even though the landscape had been recovering for 5 yr at the time of study, populations of Plethodon jordani, Plethodon glutinosus spp., Desmognathus wrighti, Desmognathus imitator, and Eurycea wilderae within the burn boundary had lower abundance than those in unburned habitat. In addition, there was a trend of even lower abundances in more severely burned habitat. Evidence of recovery, as indicated by a relationship between population abundance and distance from the burn boundary, was only present for D. imitator. Finally, body size distributions were different between burned and unburned sites for three of the five species and individuals were larger, on average, in burned sites. This work provides insights into how terrestrial salamander populations may respond to the more severe and frequent wildfires predicted under climate change for the southern Appalachian Mountains region. [ABSTRACT FROM AUTHOR]