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Wildlife Crossings in Colorado: Saving Animals, Drivers, and Ecosystems

Wildlife crossings in Colorado reduce collisions, protect ecosystems, and transform transportation for both people and animals.

By Sneha Tete, Integrated MA, Certified Relationship Coach

Created on Sep 27, 2025

Wildlife crossings in Colorado reduce collisions, protect ecosystems, and transform transportation for both people and animals.

Introduction: The Urgent Need for Wildlife Crossings in Colorado

Every year, thousands of animals in Colorado are struck and killed on highways, resulting in devastating losses for wildlife populations and serious risks to human drivers. These incidents not only threaten the rich biodiversity of Colorado but also pose a significant safety hazard, frequently leading to injury, property damage, and, in some cases, fatalities.

Wildlife crossings—special bridges, underpasses, and other engineered structures—are transforming how the state addresses this long-standing problem. These solutions are creating a safer environment for all and are now being recognized nationally for their impact and effectiveness.

What Are Wildlife Crossings?

Wildlife crossings are purpose-built structures, such as overpasses, underpasses, and tunnels, designed to help animals safely traverse highways and roads. They range from large, vegetated bridges for elk and deer to smaller culverts for amphibians and small mammals. When combined with strategic fencing to guide animals toward these passages, the results are profound: dramatic reductions in wildlife-vehicle collisions, fewer animal deaths, and much greater road safety for motorists.

In the past, highway corridors fragmented important habitats and blocked natural migration routes, threatening the survival of many native species in Colorado. The implementation of wildlife crossings is helping to restore these routes, ensuring the continued movement and genetic diversity of wildlife populations across the landscape.

Colorado’s Leadership in Wildlife Crossing Infrastructure

Colorado is at the forefront of wildlife crossing design and implementation. Known for its spectacular landscapes and abundant wildlife, Colorado has invested heavily in making roads safer for both animals and people. The state’s proactive approach has set an example for others nationwide, with collaborations between state agencies, conservation organizations, and federal partners bringing these projects from concept to reality.

The Colorado Wildlife & Transportation Alliance identified eight high-risk collision hotspots, including corridors along Interstate 70, US 285, and Highway 93 between Golden and Boulder.
Multiple agencies—such as the Colorado Department of Transportation (CDOT), Colorado Parks & Wildlife, and local governments—work together on selecting sites, designing crossings, and monitoring effectiveness.
Data-driven planning, including years of crash statistics and wildlife tracking, enables precision in targeting hotspot locations where crossings will deliver the most impact.

Notable Wildlife Crossing Projects Across Colorado

State Highway 9: Seven structures led to a 90% reduction in wildlife-vehicle collisions. Over a five-year study period, cameras recorded more than 112,000 successful mule deer crossings, with 16 other species also documented using the passages.
I-25 South Gap Project: Vital for connectivity between wildlife populations separated by the busy interstate.
US Highway 160 (Durango to Pagosa Springs): A high-collision area where more than 60% of all crashes involved wildlife. Features overpasses and multiple underpasses to serve both large mammals and smaller species, projected to reduce wildlife-vehicle collisions by 85%.

Designing for Diversity: Customized Solutions for Species and Habitats

No single wildlife crossing works for every animal. Colorado’s holistic approach tailors each structure to the local species and terrain.

Underpasses are popular with deer, bears, mountain lions, and other species that prefer shelter on their journeys.
Overpasses, often broad and vegetated, appeal to elk, bighorn sheep, and pronghorn that favor open vistas and gentle slopes.
Small critter crossings—such as tunnels filled with brush or aquatic features—accommodate reptiles, amphibians, and small mammals. Fencing and natural cover encourage safe use by even the smallest wildlife.

Trail cameras positioned at crossings often reveal an impressive diversity of animals using the structures, from moose and bobcats to snakes and protected frogs, underscoring the effectiveness of species-specific design.

The Dramatic Impact: Successes and Quantifiable Benefits

The efficacy of wildlife crossings in Colorado is not anecdotal—it’s backed by robust data and surveillance:

Crash Reductions: Installation of crossings and fencing along key corridors has led to reductions in wildlife-vehicle collisions of up to 97% in some locations.
Economic Returns: Fewer collisions mean less property damage, lower emergency response costs, and lives saved for both animals and humans. The investment yields some of the highest returns found in transportation infrastructure.
Conservation: Reconnecting fragmented habitats fortifies wildlife populations against the threats of isolation and inbreeding, ensuring long-term species survival.
Environmental Health: By reducing roadkill and keeping migration corridors open, crossings support ecosystem health and function, benefiting everything from pollinators to top predators.

Statistical Highlights

Project	Reduction in Collisions	Time Period	Species Impacted
State Hwy 9	90%	5 years	Deer, elk, moose, bear, bobcat, others
I-70 (Floyd Hill, Eagle)	Up to 97%	Ongoing	Multiple large mammals
US Hwy 160 (Durango-Pagosa)	85% projected	Project start 2022	Elk, deer, bear

Integrating Climate Change and Future Planning

A growing body of research highlights that for crossings to be truly effective in the long-term, climate change must be integrated into their planning. Rising temperatures, altered precipitation patterns, and changing vegetation are already influencing wildlife movement patterns and migration routes.

Recent studies recommend using dynamic modeling—factoring in climate projections, land use changes, and anticipated shifts in migration corridors—to select locations that will remain critical as the environment evolves.
Colorado leads by example: In southwestern Colorado, empirical modeling has mapped how elk migration routes are expected to shift with climate change, ensuring that new crossings will remain relevant decades into the future.
By prioritizing climate-resilient sites, investments today will safeguard wildlife connectivity for generations to come, adapting proactively to ecological transformations.

Funding, Policy, and Collaboration: Making Wildlife Crossings Possible

Wildlife crossings require substantial investment, detailed planning, and coordination across government, non-profits, and communities.

The federal Infrastructure Investment and Jobs Act (2021) provided $350 million over five years specifically for terrestrial wildlife connectivity and mitigation, marking the first dedicated national funding for such projects.
Colorado received a $59 million grant to fund additional wildlife underpasses, with multi-year project plans and phased construction.
Legislation such as the Wildlife Movement Through Partnerships Act and the Habitat Connectivity on Working Lands Act aim to further expand and enable private and public land collaboration for connectivity projects.
Public-private partnerships are essential; ranchers, land trusts, local contractors, Indigenous communities, and non-profits are all stakeholders in creating successful crossings that reflect community priorities and environmental needs.

Cost Versus Benefit

The up-front costs for building crossings can seem high, but the financial savings from prevented accidents, reduced insurance claims, and preserved ecosystem services rapidly add up. Once evidence from implemented projects is considered, wildlife crossings are consistently among the most cost-effective infrastructure investments in highway management.

Technology and Monitoring: How Crossings Are Evaluated

To ensure wildlife crossings meet their goals, extensive monitoring programs are deployed:

Trail Cameras: These capture images and videos of crossings in use, documenting species diversity and behavioral responses.
GPS Tracking: Some projects tag animals with GPS collars to assess how migration patterns change post-construction.
Crash Data Analysis: Systematic studies of crash reports track before-and-after rates to measure safety improvements and cost savings.
Adaptive Management: If species aren’t using crossings as planned, structures can be modified (such as by adding cover, fencing, or habitat features) to improve use rates.

Education and Public Engagement

Another key to the success of Colorado’s wildlife crossings is the involvement and support of local communities. Education campaigns inform the public about the value of crossings, dispel myths, and encourage reporting of wildlife sightings or collisions. Volunteers often participate in local monitoring efforts, and outreach events cultivate a sense of stewardship for protecting the state’s wildlife legacy.

Looking Forward: Expanding Wildlife Connectivity Statewide

Colorado continues to identify additional hotspots ripe for new crossings, expanding its commitment to reduce collisions and restore natural migration routes. Major highways, secondary roads, and even city-adjacent corridors are all under review for mitigation opportunities. As climate change alters habitats, responsive planning and new construction methods ensure Colorado’s wildlife crossings remain vital components of a resilient landscape.

Local Impact: Safe passage for animals reduces driver stress, preserves agricultural land, and fosters eco-tourism by keeping wildlife abundant and visible.
Broader Example: As more states follow Colorado’s lead, the U.S. is developing a patchwork of connected conservation corridors spanning regional and national scales.

Frequently Asked Questions (FAQs)

Q: Which animals benefit most from wildlife crossings in Colorado?

A: Large mammals like mule deer, elk, moose, black bears, bighorn sheep, and mountain lions benefit significantly. Many crossings are also used by pronghorn, bobcats, foxes, and smaller wildlife, such as amphibians, snakes, and protected frog species.

Q: Do wildlife crossings really reduce road collisions?

A: Yes. Studies confirm reductions in wildlife-vehicle collisions of between 85% and 97% on some corridors after crossings and fencing were installed.

Q: Are wildlife crossings expensive to build?

A: The initial construction can be costly, but the economic and safety benefits—lower crash rates, fewer emergency responses, and reduced insurance claims—mean that crossings offer exceptional long-term value.

Q: How do planners decide where to build a crossing?

A: Experts analyze crash data, wildlife movement patterns, and species needs to identify ‘hotspot’ locations. Modeling future environmental changes, like climate shifts, is increasingly part of site selection.

Q: What is the future of wildlife crossings in Colorado?

A: With robust state and federal support, ongoing research, and expanding public awareness, Colorado will continue to lead in wildlife crossing innovations. The state aims to create a connected network that saves lives, supports biodiversity, and adapts to changing environmental conditions.

References

Author

Sneha TeteBeauty & Lifestyle Writer

Sneha is a relationships and lifestyle writer with a strong foundation in applied linguistics and certified training in relationship coaching. She brings over five years of writing experience to thebridalbox, crafting thoughtful, research-driven content that empowers readers to build healthier relationships, boost emotional well-being, and embrace holistic living.

Read full bio of Sneha Tete