Authors:

Doyel, Jackson James, Maya Lee, Ashton Nagasuru, Fern Tatum, Richard G. Lathrop, and Jenny Isaacs. "Wildlife-vehicle risk assessment along Yellowstone's western boundary: Implications for ecological connectivity and road safety" in the Journal for Nature Conservation (June 2025). 10.1016/j.jnc.2025.126981

Abstract

(Published)

Highways impose threats to ecological connectivity and driver safety through wildlife-vehicle collisions and habitat fragmentation. United States Highway 191 cuts through the Greater Yellowstone Ecosystem, creating a barrier for wildlife that try to access public lands adjacent to Yellowstone National Park. However, there is limited knowledge on where wildlife activity and crossing events are most frequent along United States Highway 191, especially for bison which cross this road during their annual migration. We used two decades of third-party conservation organization data to highlight wildlife migratory corridors and key sites of activity in the Greater Yellowstone Ecosystem, identifying locations where proactive mitigation efforts can enhance wildlife permeability. Our study aimed to find where the implementation of wildlife crossing structures could be best placed, and what structures might be beneficial based on the species present. We conducted optimized hotspot, cluster and outlier, and linear directional mean tool analyses to locate primary highway crossing and activity hotspots for multiple species. We expected that most wildlife activity observed would coincide with local riparian corridors bridged by the highway. Our analyses revealed two primary wildlife activity hotspots near the Madison River and both Cougar and Duck Creeks, with substantially higher activity observed at the former. Due to the frequency of large ungulates and ursids present at these sites, we recommend a multi-crossing structure approach with accompanied fencing as the most effective mitigation measure to both improve ecological connectivity and reduce wildlife-vehicle collisions.