Abstract: Desmognathus salamanders are a model system for investigating how biotic and abiotic factors interact to allow for species coexistence. In streams located near the Mountain Lake Biological Station, four species ( D. quadramaculatus, D. monticola, D. fuscus and D. ochrophaeus ) are distributed across a horizontal moisture gradient from the stream into the forest floor. The differential physiological capacities to withstand drying based on habitat use and body size combined with size specific inter and intraspecific interactions largely explain this horizontal distributional pattern. Most research examining Desmognathus community structure has focused on their horizontal stream to forest distribution. However, recent data suggests that D. fuscus and D. monticola also segregate along vertical stream gradients, with distribution shifts from D. fuscus at the top of streams to D. monticola in more perennial areas. This study focuses on factors generating these vertical distribution patterns, and we hypothesized that tradeoffs between abiotic tolerances to desiccation and predation risk generate these vertical patterns. I addressed the following questions: 1) Is the shift from D. fuscus to D. monticola as one move downstream repeatable at other streams? 2) How is D. fuscus activity, growth and survivorship affected by desiccation and predation risks? In order to answer these questions, both field data and experimental manipulations were used. Strong and significant distributional shifts occurred at all streams sampled. Furthermore, D. fuscus performance was significantly affected by desiccation and predation risks demonstrating that opposing biotic and abiotic gradients potentially generate the observed field pattern.