Ecology and population demography of the hellbender, Cryptobranchus alleganiensis, in West Virginia

Using mark-recapture, I studied the population demography and habitat use of the hellbender, Cryptobranchus alleganiensis, in the West Fork of the Greenbrier River, Pocahontas County, West Virginia. Eighteen nocturnal surveys were conducted between April and October, 1998, during which 29 hellbenders were implanted with permanent tags. Male to female sex ratio was 1.06:1. Hellbenders were sexually dimorphic, as females were significantly longer and heavier than males. Total lengths for all captured animals ranged from 29.5 - 56.5 cm and mass ranged from 150.0 - 905.8 g. Seasonal linear movements for 12 individuals ranged from 0.8 - 70.2 m (mean = 19.8 m). The density was 0.8 hellbenders per 100 m2. I did not find evidence of reproduction at the study site, however, the timing of cloacal swelling of males suggested that mating took place in late August and early September. Larvae or subadults were not observed during this study. A decrease in nocturnal activity of hellbenders was observed beginning in mid July, suggesting the importance of the implementation of surveys for the species early in the year. Aggressive interactions may have been common among hellbenders at this site, indicated by wound patterns on large, adult individuals. Color variation and change was examined and compared to other sites throughout the range of the hellbender. Finally, management recommendations were suggested for the hellbender and its habitat in West Virginia