American Pronghorn Population Assessment

The goal of this project is to identify relationships between pronghorn population trajectories and climatic shifts occurring at local and ecosystem scales to inform pronghorn management. Therefore, this agreement involves 4 parts: 1) Determining how widespread the decline in American pronghorn is. 2) Identifying causal, climatic factors which best explain such declines. 3) Forecast the trend and geographical extent of these causal, climatic factors over the next century. 4) Relate these forecasts to pronghorn population trends over future decades. Specifically, the goals of this project are to: 1) Collect pronghorn population estimate (abundance) data, for as many pronghorn populations as possible, for those populations inhabiting the Sonoran and Chihuahua desert ecosystems, plus the Colorado Plateau and semi-arid prairies. This would engage pronghorn populations within the states of AZ, NM, western TX, UT and CO, plus Sonora MX. 2) Model the population trajectories of each population in conjunction with climatic variables that represent precipitation, vapor pressure deficit and temperature, and perhaps variants thereof. 3) Identify commonalities and differences between pronghorn population trajectories and the explanatory factors between populations within and across these different desert ecosystems. 4) Project model results (relationship between population change and climatic variables) in concert with downscaled climatic predictions, to predict pronghorn trends (for a representative number of populations within each desert ecosystem) and forecast abundances over the next 20, 40 and 80 years. 5) Interpret project findings to provide overarching, informative and pointed recommendations for managing American pronghorn in the SW. This step places individual population management in context which abiotic changes occurring at ecosystem scales.