Salamanders

The interior forests of the Southern Appalachians, including the area around the headwaters of the Chattooga, have been described as the salamander capital of the world. Richard Bruce, a recognized expert and lead investigator of a five-year salamander survey in the Chattooga, says our salamander fauna "may be the richest in the world for watersheds of comparable area" (Bruce et al., 1995). The area's interior forests are the evolutionary fountainhead for a widespread group, the plethodon family of salamanders.

These animals are interesting, for although they are amphibians, the moist forest soils they inhabit permit them to skip the typical aquatic phase of an amphibian's life entirely. This evolutionary novelty allowed them to colonize terrestrial areas not usually accessible to most amphibians which must lay their eggs in water. Plethodon salamanders now serve an important function as insect-eaters on the forest floor. With their vast numbers of up to five or more individual salamanders in a single square yard of soil, they consume tons of insects in a forest stand every season. However, because they breathe through their skin, they must remain in moist areas all the time, and emerge from their underground burrows only at night or in the rain.

Their specialization makes plethodon salamanders quite sensitive to disturbances to their forest interior environment. It also makes them potential indicators of ecosystem health in the mature forest. Dr. James Petranka, a biologist at the University of North Carolina at Asheville, has studied the effects of clear cutting on salamanders (Petranka, 1994). He found that salamanders are completely eliminated or reduced to very low numbers when mature forests are clear cut. Furthermore, comparisons between different-aged stands suggests that salamanders come back very slowly after an intensive timber operation. Their numbers return only over many decades as the stand grows back and the shaded, moist forest conditions return.

Given the logging history of the Chattooga, these sensitive animals are probably just beginning to return to their pre-disturbance population levels, and their proper ecological role as major forest-floor insect predators. "There's no doubt these animals are best adapted to old growth conditions," Petranka says. "Designating subsets of the landscape as permanent, non-harvestable sites is a management tool that can increase both landscape heterogeneity and regional densities of Southern Appalachian salamanders." Petranka advocates management techniques such as leaving buffer zones along headwater streams, and reversing the current trend of industrial-style management that results in forest landscapes dominated by relatively young stands of trees. Such management has the added benefit of providing greater lengths of streams that are suitable for trout and other aquatic species.

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