PART II: HABITAT SELECTION, MOVEMENTS, AND ACTIVITY PATTERNS
Petokas, Peter, Biology, Lock Haven University, 401 N. Fairview St., Lock Haven, PA, 17745, ppetokas@commonwealthu.edu; Herman, Michelle, R, , The Wetland Trust, Inc., 4729 State Route 414, Burdett, NY, 14818, mh@thewetlandtrust.org.
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. 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 and fixed RFID tracking systems secured to the stream pavement in late spring 2023. We added additional refugia to the release sites, including slab rock and artificial shelters. Habitat selection by the head-started salamanders included natural slab rock, rock clusters, placed rock, artificial shelters, and the complex streambank root systems of large, mature Willow trees (Salix sp.). Local movements were typically short with an average linear range of 51.71m for maximum upstream and downstream movements. Most individuals in the J18 cohort eventually moved downstream following initial release, while the J21 individuals remained in the vicinity of the initial release site. The fixed-antenna RFID tracking records revealed that most movements were nocturnal, taking place between sunset and sunrise. However, the J18 cohort showed significant diurnal movements between August 26 and September 3, the period during which most nesting occurs in the southern tier. While no evidence was found for reproduction by the J18 cohort, we are hopeful that some will engage in reproductive activities in the next few years, thus putting this reintroduction project on a trajectory toward a self-sustaining population.
Hellbender, RFID, Habitat, Activity