pronghorn antelope walking along the side of u.s. highway 287

287 america american animal animals antelope antilocapridae buck country county elements eventoed fast fawn getaway grand herd herding herds highway hole hoof hooves horn horns jackson mammal mammals mountains national nature park places prairie prey prong pronghorn rawlins run runner runners seasons sheep side species spring state states teton tetons travel trip united usa vacation walking white wild wildlife wyoming