Searching for the "hidden" salamander: The distribution and ecology of Desmognathus abditus

     The Cumberland Plateau in Tennessee is largely understudied in respect to stream salamander ecology and distribution. One species, the Cumberland Dusky Salamander Desmognathus abditus is the only endemic... [ view full abstract ]

     The Cumberland Plateau in Tennessee is largely understudied in respect to stream salamander ecology and distribution. One species, the Cumberland Dusky Salamander Desmognathus abditus is the only endemic surface-dwelling salamander to the region. Described in 2003 by Anderson and Tilley the salamander is still relatively understudied, though their ecology is often assumed to be similar to related species such as D. ochrophaeus and D. ocoee. To accurately describe the distribution and ecology of D. abditus, we conducted occupancy and capture-mark-recapture studies throughout their range. The distribution of D. abditus across the plateau is characterized by small populations found exclusively in perennial streams off the plateau in the sandstone layer. These sites are often characterized by bedrock cascades and waterfalls, though differences in habitat preferences may occur between northern and southern populations. Furthermore, an apparent gap in occupancy exists between Grassy Cove and Tracy City, Tennessee. Capture-mark-recapture analyses revealed that though survival was fairly similar between northern and southern populations (Southern ψ = 0.52, Northern ψ = 0.52), southern populations had much smaller temporary emigration rates (γ’’_S=0.14 relative to γ’’_N=0.85). Most populations were small with 0-65 individuals, but one locality had up to 285 individuals. Ecological and morphological differences between northern and southern populations require more extensive study to understand genetic and environmental drivers of these differences. A distribution derived from small, isolated populations coupled with specific habitat preferences suggest that attention is needed to ensure that environmental changes have minimal impacts on population persistence.