North America's largest wildlife overpass is working better than expected. Since opening in December, the crossing system over Interstate 25 in Colorado has cut animal-vehicle collisions by 91 percent.

The 209-by-200-foot bridge sits near the Greenland exit between Larkspur and Monument. It was built along a stretch where, before construction, about one deer was hit each day during peak spring and fall migration.

The bridge is part of a wider system with five wildlife underpasses and fencing that guides animals to the crossings. Trail cameras show elk herds, pronghorn, black bears, deer and coyotes all using the route. Logs placed along the deck give smaller animals shelter from predators.

"Based on the video feed that we're collecting, huge success," said Chuck Attardo, an environmental manager with the Colorado Department of Transportation.

According to Colorado Parks and Wildlife, pronghorn are crossing to the west side of I-25 for the first time in decades. Officials are still planting vegetation to make the bridge more inviting for animals.