Versatility of Habitat Use in Three Sympatric Species of Plethodontid Salamanders

Abstract

Eurycea cirrigera, a relatively small species that occurs in the Allegheny Mountains, appears to fill in the gaps along the aquatic-terrestrial gradient that are left by two sympatric salamander species; the terrestrial Plethodon cinereus and semiaquatic Desmognathus fuscus. To better understand the local distribution of these three species we tested the hypothesis that E. cirrigera is better able to utilize a variety of microhabitats than P. cinereus or D. fuscus. In field enclosures change in mass in relation to initial mass, as a proxy of fitness, was compared for each species, in three different habitats (stream, stream bank, and forest) over time. Independent of species the stream habitat showed a significant negative effect on the fitness of all individuals. Additionally, E. cirrigera showed significantly higher fitness than P. cinereus over all three treatments. The mean fitness of D. fuscus was intermediate, but not significantly different than P. cinereus or E. cirrigera. These results suggest that, in the absence of predation and competition, E. cirrigera is not negatively affected by being a generalist.