Date of Graduation

2015

Document Type

Dissertation

Degree Type

PhD

College

Davis College of Agriculture, Natural Resources and Design

Department

Animal and Nutritional Sciences

Committee Chair

Eugene E Felton

Committee Co-Chair

Robert A Dailey

Committee Member

Margaret M Minch

Committee Member

Thomas K Pauley

Committee Member

J Todd Petty

Abstract

The Eastern hellbender (Cryptobranchus alleganiensis alleganiensis ) is the largest salamander in North America growing to 75 centimeters in length. This fully aquatic species is an indicator of good stream and river quality and has been considered to be in decline or rare throughout its range. This study focused on the current distribution of the Eastern hellbender at sites of historic occurrence in West Virginia in order to determine the species' current range and factors impacting its distribution in order to facilitate planned reintroductions and translocations of hellbenders reared in human care. The success of the reintroduction and translocation efforts were also a key focus of this study to determine if the release of individuals raised in human care could contribute to the conservation of this species in West Virginia.;Results of this study have indicated that hellbenders were only detected at 12 of 23 (52%) surveyed sites of historic occurrence, and the habitat variables most strongly associated with the presence of this species at historic sites was the presence of forested landscape within the watershed and increased dissolved oxygen concentration within streams and rivers.;Key data from diet intake studies showed that 84% of hellbenders collected in West Virginia during periods of feeding had consumed crayfish with fish species being the second most frequently observed item consumed. In addition, no (39 of 39) hellbenders captured from July 8th - August 29th in West Virginia had any food items present in their stomach during surveys. The greatest factor associated with the lack of prey consumption was water temperatures in excess of 23°C. These findings were confirmed with individuals in human care with individuals maintained at these temperatures not eating and losing an average of 15.33 grams during the 86 day trial period.;Finally, we created predictive models based on sites of hellbender presence during our surveys to identify high probability of occurrence sites for translocation of head-started hellbenders. We then released 14 individuals at a reintroduction site where head-started hellbender eggs were collected as well as 15 individuals at a translocation site that was previously occupied by hellbenders. Survival rates through 6 months of tracking during this study did not differ statistically between sites. Movement and home range were greater at the reintroduction site than at the translocation site, and stream bank shelters were used more frequently than stone shelters at the reintroduction site than at the translocation site. Increased movement and alternative shelter use are believed to be due to reduced shelter availability due to fewer boulders and the presence of adult hellbenders at the reintroduction site as opposed to conditions at the translocation site. Future hellbender conservation efforts in West Virginia should include preservation of forest habitat near current hellbender populations and surveillance of historic sites based upon predictive model results. Reintroductions and translocations of head-started juveniles or sub-adults should be conducted at sites of greatest predicted occurrence with long-term monitoring for detection of reproductively sustainable populations.

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