Wildlife crossings are evolving and the details matter more than ever

Wildlife crossings are having a moment and for good reason.

Across North America, agencies, engineers and conservation groups are investing in innovative solutions that balance transportation needs with environmental stewardship. Projects like the Wallis Annenberg Wildlife Crossing and Willard Springs Wildlife Overpass demonstrate how thoughtful design can reconnect habitats, reduce wildlife-vehicle collisions and create safer travel corridors for both animals and people. According to the Federal Highway Administration (FHWA), wildlife crossings play an important role in improving habitat connectivity and reducing conflicts between wildlife and transportation networks.¹

What is a wildlife crossing?

A wildlife crossing is a structure designed to help animals safely cross human-made barriers such as highways, roads, railways and canals.

Common types of wildlife crossings include:

• Wildlife overpasses or land bridges
• Wildlife underpasses and tunnels
• Culverts designed for animal movement
• Rope bridges for arboreal species
• Aquatic crossings for fish and amphibians

These structures are often paired with wildlife fencing that guides animals toward designated crossing points, helping reduce wildlife-vehicle collisions and improve crossing effectiveness.²

Not every wildlife crossing looks the same

Wildlife crossings are not one-size-fits-all.

Different species prefer different crossing types based on their behavior, habitat and comfort level. According to the Wyoming Game and Fish Department, some animals are more likely to use open overpasses with natural vegetation and visibility, while others prefer underpasses, tunnels or culverts. Factors such as vegetation, noise levels, lighting and available cover can all influence whether animals use a crossing successfully.³

As a result, modern wildlife crossings are designed around target species, local habitats and migration patterns rather than a standard design approach.

Wallis Annenberg Wildlife Crossing: A global benchmark

The Wallis Annenberg Wildlife Crossing is one of the largest wildlife overpasses in the world.⁴

Spanning Highway 101 in Los Angeles County, California, the crossing reconnects habitat within the Santa Monica Mountains, creating safe passage for mountain lions, deer, bobcats and other wildlife.

Notable features include:

• Native vegetation designed to replicate surrounding habitat
• A crossing width of approximately 210 feet
• Public-private partnerships supporting project funding
• Collaboration among Caltrans, the National Park Service, the Santa Monica Mountains Conservancy, the Annenberg Foundation and conservation organizations

The project has become an international model for wildlife connectivity and habitat restoration in urbanized environments.⁴

Willard Springs Wildlife Overpass: Safety meets conservation

The Willard Springs Wildlife Overpass, located along Interstate 17 near Flagstaff, Arizona, addresses a corridor with a long history of wildlife-vehicle collisions.⁵

Led by the Arizona Department of Transportation (ADOT) in partnership with the Arizona Game and Fish Department (AZGFD), the project improves driver safety while restoring migration routes for elk, deer and other wildlife.

The crossing includes:

• A dedicated wildlife overpass
• Extensive wildlife fencing
• Habitat connectivity improvements
• Long-term wildlife monitoring

Projects like Willard Springs demonstrate how transportation safety and wildlife conservation can work together.

Other notable wildlife crossings across North America

Wildlife crossings are becoming increasingly common throughout North America as agencies recognize their environmental and safety benefits.

Banff National Park, Canada

Banff National Park is home to one of the most studied wildlife crossing systems in the world. Wildlife overpasses, underpasses and fencing have reduced wildlife-vehicle collisions by more than 80 percent, according to Parks Canada.⁶

I-90 Snoqualmie Pass, Washington

The I-90 Snoqualmie Pass East Project includes multiple wildlife crossings that support species ranging from elk and deer to amphibians and smaller mammals.⁷

Robert L.B. Tobin Land Bridge, Texas

Located in San Antonio, this innovative crossing combines habitat connectivity, recreational space and urban design.

Trapper’s Point Wildlife Crossing, Wyoming

One of the earliest large-scale wildlife crossing projects in the United States, Trapper’s Point helps maintain critical migration routes for pronghorn and mule deer.³

Who is involved in wildlife crossing projects?

Successful wildlife crossings require collaboration among multiple organizations and disciplines.

Typical stakeholders include:

• The Federal Highway Administration (FHWA)
• Departments of Transportation (DOTs)
• Federal agencies such as the U.S. Forest Service, Bureau of Land Management and National Park Service
• State wildlife agencies
• Conservation organizations and nonprofits
• Engineers and transportation planners
• Landscape architects and ecologists
• Local governments and communities

This collaboration helps ensure animal crossings meet transportation, environmental and community objectives.

Why wildlife crossings matter

Wildlife crossings provide measurable benefits for both wildlife and people.

Benefits include:

• Reduced wildlife-vehicle collisions
• Improved driver safety
• Restored habitat connectivity
• Protection of wildlife migration routes
• Improved biodiversity and ecosystem health
• Support for environmental and regulatory goals¹

They also help agencies and project teams address growing public expectations for environmentally responsible transportation projects.

Frequently asked questions about wildlife crossings

Do wildlife crossings actually work?

Yes. Research from Parks Canada and transportation agencies across North America shows that wildlife crossings combined with fencing can reduce wildlife-vehicle collisions by more than 80 percent in some locations.⁶

What animals use wildlife crossings?

Species vary by region but commonly include deer, elk, moose, mountain lions, bears, bobcats, pronghorn, reptiles, amphibians and smaller mammals.

Why is fencing important in wildlife crossings?

Wildlife fencing helps guide animals toward safe crossing locations. Wildlife fencing plays a critical role in directing animals to designated crossing points and maximizing the effectiveness of wildlife crossings.²

Why do some wildlife crossings go over roads while others go under them?

The design depends on the species being protected and the surrounding landscape. Larger animals such as elk, deer and pronghorn often prefer open overpasses, while some species are more comfortable using underpasses, tunnels or culverts. Wildlife biologists evaluate migration routes, habitat conditions and animal behavior to determine the most effective design.³

Where are wildlife crossings most needed?

Wildlife crossings are most effective in areas where roads, highways or transportation corridors intersect major migration routes, wildlife corridors or sensitive habitats.

Where Natina fits in

Wildlife crossings are not just about the overpass or underpass. They are about all the supporting elements that make these projects successful.

Wildlife fencing, guardrails, retaining walls, sound barriers, structural steel, rock stabilization and drainage features all contribute to a project’s performance, appearance and acceptance by the surrounding community.

As wildlife crossings become more sophisticated, project teams are paying closer attention to how these elements fit within the surrounding landscape.

Natina’s reactive color treatment helps steel, concrete and rock features blend into their environment with natural, earthy brown tones while maintaining the durability of the underlying material. Rather than drawing attention to fencing, steel or concrete, Natina helps these elements complement the surrounding landscape.

Where Natina can be used

• Wildlife fencing and animal guidance systems
• Chain-link and perimeter fencing
• Guardrails and roadside safety barriers
• Structural steel on overpasses and crossings
• Concrete retaining walls, abutments and sound barriers
• Rock, riprap and slope stabilization features
• Utility and maintenance access structures

Why it matters

Wildlife crossing projects are designed to reconnect habitats while minimizing impacts on the surrounding environment.

Natina helps project teams reduce visual impact, support environmental objectives and create a more natural appearance for the fencing, steel, concrete and rock features that make these projects possible. It is environmentally safe, low maintenance and suitable for use around sensitive ecosystems.

Connect with Natina

Planning a wildlife crossing, transportation corridor improvement or environmentally sensitive project?

Natina works with transportation agencies, engineers, landscape architects and contractors to help fencing, steel, concrete and rock features blend into their surroundings while maintaining long-term performance.

Contact Natina to discuss your project and learn how we can support your environmental and aesthetic goals.

866-797-6589
info@natina.com
www.natina.com

References

1. Federal Highway Administration (FHWA), Wildlife Crossings Program.
   https://highways.dot.gov/environment/wildlife-crossings
   
2. Western Transportation Institute, Wildlife Crossing Research.
   https://westerntransportationinstitute.org/research_projects/wildlife-crossings/
   
3. Wyoming Game and Fish Department, Over, Under, Around or Through?.
   https://wgfd.wyo.gov/wyoming-wildlife/wyoming-wildlife-magazine/over-under-around-or-through
   
4. National Wildlife Federation, Wallis Annenberg Wildlife Crossing.
   https://www.nwf.org/Our-Work/Wildlife-Conservation/Wildlife-Crossings/Wallis-Annenberg
   
5. Arizona Department of Transportation, Willard Springs Wildlife Overpass.
   https://azdot.gov/projects/northcentral-district-projects/interstate-17-wildlife-overpass
   
6. Parks Canada, Banff Wildlife Crossings.
   https://parks.canada.ca/pn-np/ab/banff/nature/conservation/eco/corridors
   
7. Washington State Department of Transportation, I-90 Snoqualmie Pass East Project.
   https://wsdot.wa.gov/construction-planning/major-projects/i-90-snoqualmie-pass-east
   
8. U.S. Forest Service, Wildlife Connectivity Resources.
   https://www.fs.usda.gov/managing-land/wildlife-crossings
   

Image credits

• Hero image: Aerial wildlife crossing over highway. Photo credit: bbsferrari/Getty Images.
• Turtle crossing warning sign along a roadway. Photo credit: Tom Fisk/Pexels.
• Square wildlife underpass crossing beneath a roadway: Photo credit: CreativeNature_nl/Getty Images
• Wildlife overpass spanning a highway corridor. Photo courtesy of Natina.
• Wildlife crossing overpass over the Trans-Canada Highway, designed to support wildlife migration and habitat connectivity. Photo credit: Steve Gadomski/Getty Images.
• Aerial view of a wildlife crossing structure spanning a highway. Photo credit: bbsferrari/Getty Images.