Dr. Pauley and Robert with Max Nickerson and Sumio Okada at the Hellbender Symposium, 2003
Robert Makowsky
Diet and Activity Patterns of the Eastern Hellbender, Cryptobranchus alleganiensis
The Eastern Hellbender, Cryptobranchus a. alleganiensis, is a large, aquatic salamander found in higher order, cold-water streams in the Ohio River drainage. Males commonly guard the eggs they fertilize, a practice uncommon for other species of salamanders. Males will also commonly fight for possession of the best breeding sites (usually under rocks). Past research has shown that when urodelan species practice male combat, the males normally reach a size as large if not larger than females. Based on these behaviors, it would be expected that males become larger than females. Contrary to this prediction, it is thought that females reach a larger overall length than males. Due to tremendous size overlap, determining gender based simply on total length (TL) can be nearly impossible. In the breeding season, males develop an enlarged cloaca that makes them easily identifiable. However, determining gender of specimens outside the breeding season can be difficult since swelling is reduced to female proportion. This research examined whether there are other sexual dimorphic characters present all year. My research focuses on determining if any measurable dimorphism exists year-around in any size class. I am also looking at different survey methods and trying to determine the status of current populations in West Virginia.