Document Details

Document Type:   Thesis
Title:   Long-Term Growth and Monitoring of the Eastern Hellbender (Cryptobranchus a. alleganiensis) in Eastern West Virginia in Eastern West Virginia.
Author:   Douglas Charles Horchler
College:   Science
Degree Program:   Biological Sciences, M.S.
Degree:   Master of Science
Committee Director:   Thomas K. Pauley
Document Availability:   Document available for World-Wide access.
Date of Defense:   04/23/2010

Amphibian declines have been well documented, specifically in the last few decades. The Hellbender, Cryptobranchus alleganiensis, one of North America's largest salamander species, has suffered dramatic declines throughout much of its range, with estimated declines of up to 77 percent recently documented in some populations. With diurnal and nocturnal searches and mark-recapture techniques, I collected data on the status of Eastern Hellbender populations in Eastern West Virginia. We re-sampled a study site on the West Fork of the Greenbrier River that was first examined in 1998 by Jeff Humphries. Long-term growth and survivorship data were collected and compared to 1998 data. Of the 29 hellbenders tagged within the West Fork site in 1998, 11 were recaptured in 2009. Eleven year mean growth of recaptured hellbenders is 3.38 cm (range 0.6cm - 4.5 cm, n=11). A notable demography shift in both sex and size occurred from 1998 to 2009. In 1998 the population exhibited a 1.1:1 sex ratio, while the 2009 population exhibited a 2.1:1 ratio. A marked shift in size class was noted, with the 2009 population exhibiting shifts to larger size classes. However, evidence of reproduction was found in 2009 where it was lacking in 1998, potentially suggesting a viable population. The recapture data will allow for a better understanding of the growth and age of large size classes of hellbenders. 

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