Colorado doesn't currently have any animal bridges, or any animal-themed bridges that I know of. However,
Vail Pass bisects a heavily forested area where wildlife travel between the Eagles Nest Wilderness and the Holy Cross Wilderness and beyond. The Southern Rockies Ecosystem Project is proposing that a wildlife overpass be built across Interstate 70 on the west side of Vail Pass, similar to this wildlife overpass crosses the Trans Canada Highway near Banff National Park.

Here's the one in Canada.