Pronghorn are North America's fastest land mammals and longest-distance migratory ungulates, but their ancient migration routes are increasingly blocked by fences that cause exhaustion, injury, and death.
Pronghorn welfare is acutely affected by fence barriers during migration and severe weather events. When fences block access to winter range during blizzards, pronghorn can die in large numbers pressed against fence lines — exhausted, hypothermic, and unable to reach food and shelter. This is not a statistical abstraction but a welfare event affecting individual animals experiencing profound stress and suffering. Fence modification to allow crawl-through is a low-cost, high-impact welfare and conservation intervention: restoring connectivity along key corridors allows behavioral expression of the migration imperative that is fundamental to pronghorn ecology. The effort required from individual ranchers to modify fences is modest, and the wildlife benefits are substantial. Programs providing cost-sharing for wildlife-friendly fencing modifications represent excellent welfare-per-dollar investments.