BLM Wyoming Grant: Pronghorn Population Response Study in Red Desert, Wyoming

Pronghorn (Antilocapra americana), inhabit expansive, relatively flat areas of grassland and sagebrush steppe. This ungulate species is endemic to North America, with â¿¥50% of the worldwide pronghorn population occurring in the state of Wyoming, making research of the pronghorn within this state crucial for our understanding of the entire species. Over the past two decades, Wyoming has experienced changes in environmental conditions, particularly in the form of severe droughts, which have the potential to negatively impact wildlife by limiting forage availability and degrading body condition, ultimately resulting in decreased productivity and survival. Wyoming has also seen some of the greatest increases in resource extraction nation-wide as growing importance is placed on domestic production. According to the United States Energy Information Administration, Wyoming is the second highest energy producer in the country after Texas, ranking as the nationâ¿¿s leading producer of coal and fifth in natural gas production. Impacts of such infrastructure have the potential to affect wildlife by altering movement patterns, habitat selection, behavior, and demography and have increasingly become the focus of management and conservation efforts.

This project involves the continuation of on-going research to evaluate productivity, resource selection, and response to anthropogenic disturbance and environmental change for adult pronghorn influenced by oil and gas development in the Red Desert of south-central Wyoming. This project was proposed in coordination between the University of Wyoming, Wyoming Game and Fish Department (WGFD), Industry and the BLM RFO to answer specific questions on potential impacts to pronghorn from development. The WGFD directly manages pronghorn, the BLM directly manages pronghorn habitats, and both agencies are concerned about and have questions pertaining to population health in specific areas containing public, private, and state lands. Pronghorn inhabiting the WGFD Baggs, Bitter Creek, and eastern Red Desert Herd Units are under increasing pressure from similar changing environmental conditions and growing energy infrastructure, where they have struggled to recover from population declines over the past 20 years. To evaluate the additive influences of such environmental change and expanding energy infrastructure on pronghorn in these three study areas, we will continue to compare resource selection and demographic responses of 133 female pronghorn (10 fitted with VHF collars, 123 fitted with store-on-board GPS collars) in these areas to those of 53 females (12 fitted with VHF collars, 41 fitted with store-on-board GPS collars) in the northern portion of the Red Desert, where energy development is minimal.

b. Objectives:

This project is located within the Continental Divide/Wamsutter II (CD/WII EIS), Atlantic Rim (AR EIS), Desolation Flats (DF EIS) and a Control Area west of Rawlins, Wyoming and north/south of Wamsutter, Wyoming. The objectives of this project are to: (1) To evaluate adult survival and recruitment of young pronghorn in the project area relative to exposure to anthropogenic and environmental change; (2) To assess multiple aspects of pronghorn movement ecology (including rate of movement, movement distance, daily net displacement, and tortuosity or path complexity) in relation to exposure to anthropogenic change; and (3) Generate a step selection function (SSF) to help explain fine-scale behavioral responses to anthropogenic change that are reflected in pronghorn movement patterns.