Effects of riparian buffer width on stream salamander populations in the southern Appalachian Mountains

Amphibians are often considered indicators of biological health, but populations worldwide have been declining over the past two decades. These declines have raised concerns about land use and the condition of the environment. Direct anthropogenic changes to the landscape such as fragmentation, conversion, and resource extraction have led to extensive habitat losses, which have been cited as the major cause of observed declines. Amphibians are particularly sensitive to habitat alterations as many species depend upon both aquatic and terrestrial habitats for completion of complex life cycles. In order to address the imperative of amphibian declines and to conserve amphibian populations, it is essential that we first define and protect essential habitat.;Salamanders are integral to the ecology of the headwater ecosystems they inhabit, where they are the most abundant vertebrates with biomasses exceeding that of small mammals and breeding birds. It has been speculated that the southern Blue Ridge physiographic province is the center of North American salamander diversity, the majority of these salamanders are found in close association with headwater stream habitats, and have biphasic life cycles consisting of an aquatic larval stage and a terrestrial adult stage. The success and prolificity of salamanders in the Appalachians is highly dependent upon riparian forests and the microclimate therein.;One the most pervasive threats to riparian habitat is timber harvesting. Current regulations require a minimal riparian buffer to be retained along headwater and low order streams to mitigate the effects of logging. These measures are likely inadequate based upon the known biology of salamanders and the environmental changes that ensue riparian forest removal. Salamanders in the Appalachian region have been extensively studied, but the majority of research assessing the impacts of logging has focused on terrestrial species that are not dependent on stream habitats for egg deposition or larval development. I have collected data on both larval and adult salamanders in headwater streams in western North Carolina to determine the impacts of even-aged timber harvest on salamander populations and to assess the efficacy of riparian buffers in ameliorating these effects.;My data show that larval two-lined salamanders are negatively impacted by increased stream sedimentation following riparian logging and that increasing the riparian buffer around the stream reduces sedimentation effects while larval black-bellied salamanders were not significantly affected by riparian treatments. Adult and juvenile salamanders dependent on terrestrial habitat were also affected; seal salamander densities were significantly higher in streams with little to no riparian buffer while Ocoee salamanders were significantly less abundant. I also showed that it is unlikely that salamanders will persist or thrive for more than a season or two in logged forests due to a significant deterioration in body condition of Ocoee salamanders in logged riparian areas. My results indicate that current riparian forest conservation measures are inadequate to preserve either larval or adult salamander populations.