Abstract
Climate change is expected to systematically alter the distribution and
poEurycea pulation dynamics of species around the world. The effects are
expected to be particularly strong at high latitudes and elevations, and
for ectothermic species with small ranges and limited movement
potential, such as salamanders in the southern Appalachian Mountains. In
this study, we sought to establish baseline abundance estimates for
plethodontid salamanders (family: Plethodontidae) over an elevational
gradient in Great Smoky Mountains National Park. In addition to
generating these baseline data for multiple species, we describe methods
for surveying salamanders that allow for meaningful comparisons over
time by separating observation and ecological processes generating the
data. We found that Plethodon jordani had a mid-elevation peak
(1500 m) in abundance and Desmognathus wrighti increased in
abundance with elevation up to the highest areas of the park (2025 m),
whereas Eurycea wilderae increased in abundance up to 1600 m and
then plateaued with increasing uncertainty. In addition to elevation,
litter depth, herbaceous ground cover, and proximity to stream were
important predictors of abundance (dependent upon species), whereas
daily temperature, precipitation, ground cover, and humidity influenced
detection rates. Our data provide some of the first minimally biased
information for future studies to assess changes in the abundance and
distribution of salamanders in this region. Understanding abundance
patterns along with detailed baseline distributions will be critical for
comparisons with future surveys to understand the population and
community-level effects of climate change on montane salamanders.