Picture a grizzly bear pacing along a Montana highway, searching for a way across. His GPS collar tells the story: over 40 attempts to cross Interstate 90, each one a gamble with his life. The bear, nicknamed "Lingenpolter" by locals, eventually made it. But his struggle reveals a critical problem facing wildlife across North America.

Every day, motor vehicles kill more than 1 million vertebrates in the United States. These collisions claim hundreds of human lives annually, injure thousands more, and cause at least $8 billion in property damage. Yet there's a solution gaining momentum: wildlife crossing infrastructure that's proving remarkably effective at saving both animal and human lives.

Why Roads Are Deadly Barriers

Highways don't just pose collision risks. They slice through habitats, creating invisible walls that prevent animals from reaching food, mates, and shelter. This fragmentation ranks among the leading causes of wildlife population decline.

Consider the red wolf. Fewer than 20 survive in the wild in Eastern North Carolina. In a single year, vehicles killed five of them, including a two-year-old named "Muppet." For a species teetering on extinction's edge, each road death is catastrophic.

Animals must cross dangerous terrain to survive. They follow ancient migration routes, seek seasonal food sources, and search for mates to maintain genetic diversity. When roads block these movements, populations become isolated. Isolation leads to inbreeding, reduced adaptability, and eventual collapse.

How Wildlife Crossings Work

Wildlife crossings come in various forms: overpasses that bridge highways, underpasses that tunnel beneath them, and modified culverts that provide safe passage. The design depends on the species and landscape.

The most effective crossings share common features. They're placed where wildlife naturally moves, not just where construction is convenient. A California study found that poorly located underpasses went unused because they didn't align with animal travel patterns. Location matters more than almost anything else.

Crossings work best when paired with fencing. The fences funnel animals toward safe passage points rather than letting them wander onto highways. This combination can reduce collisions by up to 97% when properly implemented.

Over 1,000 wildlife corridors now operate across the United States. One Arizona overpass logged more than 6,000 crossings by bighorn sheep, bobcats, deer, coyotes, and other species as of 2020. These aren't occasional use structures—they're highways for wildlife.

Species Have Preferences

Not all animals use crossings the same way. Research shows distinct preferences among species.

Elk, wolves, grizzly bears, and deer favor wide, high, short crossings. They want open views and quick passage. Cougars and black bears, by contrast, prefer long, narrow underpasses. These solitary predators feel safer in enclosed spaces.

Some species need time to adjust. Grizzly bears and wolves may take up to five years before consistently using new crossing structures. They're cautious animals that thoroughly investigate unfamiliar features in their territory. Patience pays off—once they accept a crossing, they use it regularly.

Florida black bears demonstrate the long-term benefits. Wildlife crossings in their habitat increased gene flow between populations while preventing vehicle collisions. The structures addressed both immediate safety concerns and long-term genetic health.

Montana's Ambitious Plans

Montana is emerging as a leader in wildlife crossing infrastructure. The state's efforts center on Interstate 90, which cuts through critical habitat connecting Yellowstone to Yukon.

On December 30, 2025, the Vital Ground Foundation and Yellowstone to Yukon Conservation Initiative announced the purchase of two key parcels near Missoula. The 40-acre Nellie Creek property on I-90's south side cost approximately $250,000. The 50-acre Brock Creek parcel on the north side ran about $346,000.

These land acquisitions complement engineering work already underway. The Montana Department of Transportation is studying the Sixmile Creek area, where a 60-year-old culvert needs replacement. The proposed solution: two large open-span bridges between mile markers 79.3 and 86.6.

The Sixmile project targets grizzly bears, black bears, elk, deer, and native fish. But it goes beyond simple bridges. Plans include "jump outs"—earthen mounds that let animals escape if they accidentally enter the highway. Double cattle guards and electric mats at the Huson and Ninemile Exit interchanges will further discourage animals from entering dangerous zones.

Jamie Jonkel, a bear biologist with Montana Fish, Wildlife & Parks, notes the area's importance: "We've had grizzly activity there off-and-on for the last 8-10 years." The infrastructure will formalize what animals have been attempting naturally.

The Missoula Regional Connectivity Group proposed the Sixmile project through Montana's Wildlife and Transportation Partnership Program. Funding came from the Cinnabar Foundation, Atira Conservation, and the Heart of the Rockies Keep It Connected Program. This collaboration between government agencies, nonprofits, and private donors represents the modern approach to wildlife conservation.

Proven Success Stories

Banff National Park in Canada provides compelling evidence of crossing effectiveness. Studies there show reduced roadkill, increased access to food and shelter, and decreased stress levels in wildlife populations. The crossings don't just prevent deaths—they improve overall ecosystem health.

The benefits extend beyond individual animals. When populations reconnect, genetic diversity increases. Animals access larger territories, reducing competition and stress. Predator-prey dynamics normalize across broader landscapes.

Climate change makes connectivity even more critical. As temperatures shift and habitats change, species must move to survive. Wildlife crossings provide escape routes from deteriorating conditions and pathways to more suitable environments.

Growing Investment and Future Outlook

The Infrastructure Investment and Jobs Act of 2021 provided record funding for wildlife crossings. This federal commitment sparked a construction boom. At least 12 states now have dedicated wildlife corridor programs.

The investment makes economic sense. An $8 billion annual price tag for wildlife-vehicle collisions dwarfs the cost of building crossings. A single overpass might cost several million dollars, but it prevents countless collisions over decades of use.

Public support is strong. People understand the dual benefit: safer roads for drivers and survival corridors for wildlife. There's proven effectiveness in reducing both human and wildlife mortality while allowing animals to move across highways.

Montana's grizzly bear Lingenpolter eventually found his way across I-90 west of Drummond. His GPS collar showed the relief of finally connecting with habitat on the other side. Future bears won't need to make 40 attempts. They'll have safe passages designed specifically for their needs.

The transformation of America's highway system continues. Roads that once severed ecosystems are being retrofitted with bridges and tunnels that restore connections. It's infrastructure that serves both civilization and wilderness—a rare achievement in our increasingly crowded world.