(Hosted by Eric Sargis)
Anthropogenic activities are rapidly changing natural environments on local to global scales, calling into question the persistence of ecosystems as habitats shift and species ranges collapse or move across the landscape. Temporal comparisons at the decadal to centennial scale can help understand the ecological impacts of past environmental change in order to anticipate future changes. Here we examine small mammal community similarity using paired survey data spanning an 80 year interval in two mountain ranges in the Great Basin of western North America. Using a multi-species occupancy model we account for detection and use the detection-corrected occurrence data to compute measures of community similarity within and among time periods for each mountain. In both mountain ranges, greatest community stability over time is at high elevations. However, patterns of similarity within each time period show that these two mountain ranges have arrived at this common pattern through different trajectories, likely shaped by different land use histories against a backdrop of similar changes in climate. This work emphasizes the importance of interpreting temporal changes within the context of spatial variation along the elevational gradient within each time period.