Wildlife Crossings: Engineering Solutions for Animal Movement

Roads fragment habitats and kill millions of animals annually. Wildlife crossings — underpasses, overpasses, and culverts — restore ecological connectivity and reduce wildlife-vehicle collisions.

Key Facts

Roads kill an estimated 1 million vertebrates per day in the US alone through vehicle collision
Wildlife crossings reduce roadkill by 80-95% at monitored sites when properly placed and fenced
The Banff wildlife overpass in Canada is used by bears, wolves, elk, coyotes, and dozens of other species
Underpasses can be cost-effectively retrofitted under existing roads; overpasses require more substantial investment
The Netherlands has over 600 wildlife crossings and has documented significant species recovery benefits

Welfare Considerations

Wildlife crossings address a welfare problem — road mortality — and an ecological problem — habitat fragmentation — simultaneously. The engineering solutions are proven: properly designed crossings with appropriate fencing to guide animals toward them achieve dramatic reductions in collision deaths. The barrier to wider adoption is political and financial rather than technical. Infrastructure investment decisions rarely account for wildlife mortality costs, and advocacy is needed to ensure crossing design is standard in new road projects and retrofitted on existing high-risk routes.

What You Can Do

Advocate for wildlife crossing requirements in road infrastructure planning in your area
Support organisations like the Road Ecology Center that research and promote crossing solutions
Drive at reduced speed in habitats where wildlife-vehicle collisions are common, especially at dawn and dusk
Report roadkill incidents to citizen science databases that help identify high-risk locations for intervention