PART I: GROWTH, BODY CONDITION, AND SURVIVORSHIP
Herman, Michelle, Science, The Wetland Trust, Inc., 4729 State Route 414, Burdett, NY, 14818, mh@thewetlandtrust.org; Petokas, Peter, J, Biology, Lock Haven University, 401 N Fairview St, Lock Haven, PA, 17745, ppetokas@commonwealthu.edu.
The Eastern Hellbender (Cryptobranchus a. alleganiensis), a giant and long-lived aquatic salamander, had virtually disappeared from the upper Susquehanna River watershed by the early 1990’s. In an effort to restore a functionally extirpated hellbender population, we collected eggs and larvae from PA and NY and brought them to the WCS Bronx Zoo for rearing until 3-1/2 years of age. We released 99 juveniles in 2018 (J18 cohort) and 124 in 2021 (J21 cohort), into a historical hellbender stream in the southern tier of NY. We released 99 juveniles in 2018 (J18 cohort) and 124 in 2021 (J21 cohort). Prior to release individuals were tagged with a unique RFID microchip and subsequently relocated about twice per month from June through October each summer season using hand-held RFID tag readers. When possible, we recaptured juveniles at the site once a year for health assessment. Individuals that remained at the release site (and did not migrate away) have exhibited significant annual growth and maintained a healthy body condition (based on body-mass index) while feeding on invasive Rusty Crayfish (Faxonius rusticus). Juvenile survivorship also appears to stabilize and remain high after about one year in the wild. We hope these initial positive results will ultimately shift the trajectory toward a self-sustaining population, as the juveniles released in 2018 are now approaching sexual maturity and may engage in reproductive activities in the next few years.
hellbender , survivorship , headstarting