Amphibian declines

Nearly one third of amphibian populations are declining globally, including several species in North America. Two factors that complicate the conservation of amphibians are poor knowledge of the status of their populations and limited understanding of their responses to various threats. The southeastern and mid-Atlantic regions of North America are home to some of the greatest amphibian diversity in the world and they are imperiled by many of the same factors that threaten species across the world. Habitat loss is possibly the greatest threat to amphibians in these regions due to the rapid growth of human populations and subsequent land development.

More about Hellbenders

The Hellbender, Cryptobranchus alleganiensis, is one of North America’s most unique amphibians. It is a giant, totally aquatic salamander that, along with only two other extant species, comprises the amphibian family Cryptobranchidae. Hellbenders inhabit cool, swiftly-flowing streams in the foothills and mountains of the Appalachian and Ozark mountains. Adults and large juveniles feed almost exclusively on crayfish, although they will eat many other prey as well. Anecdotal reports suggest that many streams that Hellbenders historically occupied are now devoid of these amazing animals. Although many populations are doing well, collection pressure and factors that degrade stream quality, such as watershed development or the destruction of forested riparian areas, are presumably responsible for declines at many locations. Increased siltation and runoff into their streams can alter the stream bottom and fill in many of the rocky and rubble-strewn areas that Hellbenders rely on for reproduction, refuge, and foraging. The closely related Ozark Hellbender subspecies, C. a. bishopi, is now believed to be represented by fewer than 600 individuals in the wild and is a candidate for Endangered Species Listing.

Meet the Eastern Hellbender

*Hellbender research in the Hopkins Lab is the result of a partnership with the Virginia Department of Game and Inland Fisheries, funded through the State Wildlife Grants Program.

Our ongoing research

In the summer of 2007, the Hopkins lab began stream surveys in the Commonwealth of Virginia to re-evaluate Hellbender sites based on historic records to help the Virginia Department of Game and Inland Fisheries determine the status of the species in the state.*  In both 2007 and 2008, we surveyed multiple locations in two important Virginia streams that encompassed a range of watershed disturbance and habitat alteration. One of our primary goals was to determine the relative health of the populations and examine any possible correlations of Hellbender abundance with local and watershed land use. In the next few years, we plan to expand our work to examine possible consequences of land use on the health and stress physiology of Hellbenders in different stream catchments in relation to habitat quality and watershed land use.

*Hellbender research in the Hopkins Lab is the result of a partnership with the VA Dept of Game and Inland Fisheries, funded through the State Wildlife Grants Program.

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