Ecology of the eastern long-tailed salamander (Eurycea longicauda longicauda) associated with springhouses
Date
2015
Authors
Nazdrowicz, Nathan H.
Journal Title
Journal ISSN
Volume Title
Publisher
University of Delaware
Abstract
I investigated the ecology of Eurycea longicauda longicauda (eastern long-tailed salamander) because biological information for developing conservation strategies on the species is lacking. On the piedmont of Delaware and Pennsylvania, populations of E. longicuada may be associated with springhouses. E. longicauda utilize the spring within springhouses for reproduction and to overwinter, and their activity cycle occurs as a regular migration between terrestrial and subterranean habitats. Adults begin movements into springhouses in August with males arriving before females, while immature individuals remain active in terrestrial habitats until November. Within springhouses, mating occurs prior to moving deeper within the spring to overwinter. Eggs are laid singly underwater usually in November and females do not exhibit parental care. Rather, females scatter eggs and choose oviposition sites to maximize survival. Sites are selected that maximize surface area of the egg exposed to water to allow for gas exchange. Adults emerge from overwintering in April and migrate to surface habitats. Eggs hatch after approximately 7-9 weeks and larvae migrate to surface streams in March. Larvae metamorphose from May to August, although on rare occasions overwintering of larvae occurs. Population estimates per springhouse ranged from 40-49 to 1,216-1,456 adults per year, with three study sites showing stable populations, one declining, and one increasing during the study. Sex ratio was even to male biased and juveniles comprised 11-35% of the total population per year on average. The majority of adult males and females were captured inside springhouses and during the breeding season. Recapture rate for adult males and females ranged from 0.19-0.48; however, recapture rate for unknown sex of adult size was ≤0.10, suggesting the dispersal cohort arises from this group. Occupancy of springhouses was related to landscape factors such as forest area and total stream length suggesting that habitat quantity and connectivity are important components influencing E. longicauda distributions. Species conservation might best be achieved by maintaining forest corridors between springheads. If springhouses are present, I suggest maintaining or restoring these structures in a manner that minimizes drafts and reduces or eliminates light. If eggs are observed, increasing available surface area may increase population abundance.