Ecological Genetics of the Salamander Desmognathus guadramaculatus from Disturbed Watersheds in the Southern Appalachian Biosphere Reserve Cluster

Abstract: Ecological and genetic properties of the largely aquatic salamander, D. quadramaculatus, were assessed in paired control and logged watersheds in two forests of the Southern Appalachian Biosphere Reserve Cluster. Salamanders were larger but relatively less abundant in watersheds of the more extensive and more recently cut forest. Genetic diversity derived from electrophoretic analyses of 14 loci was lower in the forest where the time available for population recovery was least. Populations in relatively undisturbed watersheds in both forests, however, tended to exhibit lower heterozygosity levels than those in previously logged watersheds, but the differences were not as striking. Confounding effects from elevation differences among watersheds were also detected. An analysis of the six subpopulations using Wright's F statistics showed moderate levels of genetic differentiation among the subpopulations. The genetic and ecological differences among populations between the two reserves are interpreted in relation to recent ideas of bottleneck theory and genetic diversion, the history of disturbance and patch dynamics, and population viability and reserve structure.