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About Us < Features < Winter 2007 < Amphibians in the Blue Ridge and the Tropics
According to an ongoing Global Amphibian Assessment (GAA), about one-third of amphibian species worldwide are threatened. What are the implications of such dire statistics for amphibians in our area? The Southern Appalachians, in particular, support
the world's greatest diversity of salamander species. This diversity is evident in and around Beech Creek in the Upper Tallulah River watershed. At least 18 species of frogs and salamanders occupy the seeps, streams, and forest floor at this site. Some species, like seal salamanders (Desmognathus monticola), remain in or near water for much of their life cycle. Other species, like salamanders in the genus Plethodon, are fully terrestrial.
The GAA categorizes almost one-quarter (23%) of amphibian species as "data-deficient," meaning there is not enough information to assess their status. Not surprisingly, many of these under-studied species occur in the tropics. However, some of these species are residents of the Southern Appalachians, where biologists have been studying the life history, behavior, and genetics of salamander populations
for decades.
Salamanders tend to be nocturnal and fossorial (adapted for burrowing), making them difficult to study. In addition, the taxonomic status of many species is unclear. For example, the dwarf black-bellied salamander (Desmognathus folkertsi), a diminutive relative of the black-bellied salamander (D. quadramaculatus), was recognized as a distinct species only four years ago by Carlos Camp, a professor at Piedmont College. To date, this newly described species of stream salamander has been found only in the Tennessee and Chattahoochee River watersheds in North Georgia. However, during a recent hike along a section of Beech Creek in North Carolina, I found a curious-looking black-bellied salamander and showed it to Camp and other experts. The animal turned out to be a dwarf black-bellied salamander, which means there is at least one population in the headwaters of the Savannah River drainage. As this example shows, we still have a lot to learn about the species in our own backyard.
Scientists have been narrowing in on some of the causes of the enigmatic declines of amphibians highlighted in the GAA. One culprit is a pathogenic fungus that infects the skin of amphibians, causing the disease chytridiomycosis. First described in 1998, this fungus occurs in the Southeast but does not seem to be causing mass die-offs like those witnessed in Central America and other areas. Global warming and the pending decline of hemlocks may pose additional challenges to amphibians in the southern Blue Ridge.
With all these looming threats, we cannot assume that the seemingly healthy populations of amphibians in our area will remain so in the future. Long-term monitoring programs for amphibians are needed now more than ever. Luckily, thanks to organizations like GWF and its supporters, there are still places to conduct those studies… and even make surprising discoveries during a hike in the woods!
Betsie Rothermel (rothermelb@apsu.edu) is an Assistant Professor in Biology and a Researcher in the Center of Excellence for Field Biology at Austin Peay State University in Clarksville, Tennessee. For more information, visit Southeast Partners in Amphibian and Reptile Conservation (http://www.separc.org/) and Global Amphibian Assessment (http://www.globalamphibians.org/).
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