Effects of Physicochemical Parameters and Land-Use Composition on the Abundance and Occurrence of Eastern Hellbenders (Cryptobranchus alleganiensis alleganiensis)

Altered landscapes have negative effects on stream habitats through altering hydrologic, sediment, and nutrient cycling regimes. These changes often reduce or displace populations of sensitive biota. The hellbender (Cryptobranchus alleganiensis) is an imperiled salamander endemic to eastern North American streams. Although once widespread, hellbender distributions have contracted and populations have declined in the past several decades. Many consider hellbenders indicators of stream health; however, few studies have empirically linked hellbender presence to habitat or water quality. I examined the utility of riparian and catchment-scale land-use and local physicochemical habitat parameters to predict hellbender occurrence in an Appalachian river drainage. Models suggest that both local habitat attributes and catchment-scale land-use/land-cover signficiantly predict hellbender occurrence and abundance. Because broad-scale land-use changes likely affect hellbender distributions, management and conservation efforts should focus on protecting stream catchments. Localized changes are also likely important but the high economic value of other cold-water resources in the area and existing streamside management guidelines may help buffer land-use impacts. Lastly, extinction debt associated with historical or recent land-use changes in parts of this quickly changing watershed possibly has yet to be realized.