Site-level habitat models for the endemic, threatened Cheat Mountain salamander (Plethodon nettingi): the importance of geophysical and biotic attributes for predicting occurrence
The federally threatened Cheat Mountain salamander (Plethodon nettingi; hereafter CMS) is known to occur in approximately 70 small, scattered populations in the Allegheny Mountains of eastern West Virginia, USA. Current conservation and management efforts on federal, state, and private lands involving CMS largely rely on small scale, largely descriptive studies of habitat associations from a few sample sites. To address the critical need for quantitative data, we used an information-theoretic approach to elucidate site-level habitat relationships of CMS relative to a suite of biotic and abiotic habitat variables measured across the species’ range. We collected data on 18 explanatory habitat variables at CMS-occupied (n = 67) and random (n = 37) sites in the summer of 2006 and examined CMS habitat relationships using a priori, logistic regression models with information-theoretic model selection. Overall, results indicated that the probability of CMS occurrence at a fine spatial scale increased in areas with shallower depth to rock, areas proximal to rocky outcrops but distal to seeps, areas with higher densities of bryophytes, and areas with high densities of red spruce (Picea rubens) and eastern hemlock (Tsuga canadensis). Within the Allegheny Mountains, associations between CMS and abiotic habitat features appear to be important predictors of site-level occurrence, although vegetation associations interact to form more precise habitat relationships within forested landscapes. The information gained from our study should increase the capacity of managers to plan for the continued persistence and conservation of Cheat Mountain salamanders in this landscape.