Habitat Preferences of the Eastern Hellbender in West Virginia

The Eastern Hellbender, Cryptobranchus alleganiensis alleganiensis, is a species of concern in West Virginia and is in need of management. An important component of conservation efforts will involve identifying suitable habitat for protection. The goal of this research was to locate populations and examine hellbender habitat preferences to help managers identify habitat for protection. Populations were located using rock turning surveys from May through November, 2006. Hellbenders may be sensitive to water chemistry, so the dissolved oxygen, pH, turbidity, specific conductivity, and water temperature were measured. Substrate composition may influence populations, so substrate was characterized with Wolman pebble counts. Crayfish relative abundance was measured because they are an important prey item. Mean habitat characteristics of sites where hellbenders were present and absent were compared with t-tests. Habitat variables were ordinated in princip al component analysis and examined in 2-dimensional ordination space to determine if sites where hellbenders were present grouped. Populations were found at 12% of sites, indicating that populations have declined in many streams. Hellbenders preferred sites with a large amount of gravel and cobble, cool water temperatures, low specific conductivity, and lower pH values. Gravel and cobble substrates may provide habitat for larval hellbenders and invertebrate prey items. Cool streams allow for more efficient cutaneous gas exchange. Low specific conductivity may indicate undisturbed conditions, suggesting hellbender populations were concentrated in less disturbed streams. Acidic conditions can alter prey communities and affect amphibian survival, so it was surprising to find populations in more acidic streams, although levels were above those known to harm stream ecosystems. Streams with similar habitat characteristics should be protected to conserve this unique salamander

Response of streambreeding salamander larvae to sediment deposition in southern Appalachian (U.S.A.) headwater streams

SUMMARY 1. Increased fine sediment deposition is a prevalent threat to stream biodiversity and has been shown to impact stream-breeding salamanders negatively. However, their complex life histories make it difficult to determine which stage is affected. 2. We conducted field experiments from 26 August to 11 September 2010 and 11 October to 11 November 2010 in two southern Appalachian headwater streams (U.S.A.) to examine the response of larval salamanders to increased fine sediment deposition. Fine sediment was increased in artificial stream channels by 0, 33 and 67%. The number of larvae observed at the end of the experiments was used to determine whether larval microhabitat selection was influenced by fine sediment deposition. A concurrent survey of aquatic larvae in three nearby streams complemented this experiment. Stream substratum composition at survey sites was quantified to examine the effects of fine sediment on larval salamander abundance. 3. Increases in fine sediment deposition failed to explain the number of larval salamanders detected in stream channels. Similarly, a negligible effect of fine sediment was observed on abundance estimates. 4. These results suggest that fine sediment deposition has a minimal impact on aquatic salamander larvae. Therefore, the effects of increased fine sediment loads on stream-breeding salamanders may not be the result of deleterious effects on the aquatic larvae but instead may be the result of effects on other stages. Management efforts that consider these other stages are therefore needed to protect stream-breeding salamander communities