The terrible cost of vehicle-wildlife collisions, and what we can do about it

Pronghorn crossing a road.

Pronghorn crossing a road: Studies show that wildlife overpasses and underpasses could reduce vehicle-wildlife collisions by 90 percent. (Tom Koerner/U.S. Fish and Wildlife Service)

Most people would be surprised to learn that the combined distance of paved highways in the United States could circle the Earth more than 160 times. While these roads and highways constitute critical infrastructure, there are significant downsides to all that asphalt and concrete, including vehicle collisions with wildlife. These accidents cause some 200 human deaths and 26,000 injuries each year, which causes over $8 billion in property damage, health care costs and lost work days, according to the US Department of Transportation.

Collisions are, of course, a losing scenario for wildlife too, and not just because of the immediate toll they take on animal lives. In Wyoming, for example, the mule deer population, which supports more than $300 million in annual hunting-related spending in the state has declined by 40 percent since 2000, due in large part to habitat fragmentation caused by roads and development. But there’s good news: Recent advances in science and policy have given us the tools to help solve this problem, starting with an understanding of how and where wildlife moves.

The phenomenon of terrestrial wildlife migration, between cooler, higher summer habitats and lower elevations with more accessible food in winter, is widespread among many species, particularly large game such as elk, pronghorn, and the deer. Many of these seasonal routes are thousands of years old and in some cases are taught from generation to generation. Migration, which can cover hundreds or even thousands of kilometres, is vital for the survival of these animals; it also benefits not only communities that depend on income from hunters and wildlife-viewing tourists, but also families that rely on big game for food.


Advances in investigative technology over the past decade have revolutionized experts’ understanding of how wildlife moves across landscapes and are now helping to resolve wildlife-vehicle conflicts that are increasing due to increased developing. An example is gps collars They target large game, as well as other mammals and birds, and transmit electronic signals via satellite from some of the most remote regions of the US to researchers across the country. This data captures exactly where and when animals move within large landscapes, allowing scientists and engineers to identify where the construction of wildlife crossings, mostly overpasses and underpasses that help animals cross roads. , can more effectively improve the safety of motorists and facilitate animal migrations. Studies show that a well-placed underpass or overpass can reduce wildlife vehicle accidents by more than 90 percent, providing a high rate of return on federal and state investments in such structures.

A wildlife overpass in Montana.
A wildlife overpass on the Flathead Indian Reservation in western Montana.

(Montana Department of Transportation)

In addition, by taking much of the guesswork out of annual species movements, advances in migration science allow elected officials, land managers, and transportation and wildlife agencies to shape policy. In fact, numerous states have taken bipartisan action related to wildlife habitat this year, with California, Colorado, New Mexico, Oregon, Utah, and Wyoming enacting laws designed to reduce animal-vehicle collisions by investing in transportation infrastructure such as overpasses and underpasses and other measures to improve habitat connectivity.

At the federal level, the Infrastructure Investment and Jobs Act of 2021 includes billions of dollars over five years for wildlife and aquatic connectivity programs, along with $350 million for a new wildlife crossing construction program. It is now up to agencies like the Federal Highway Administration to efficiently implement these programs so that tribes, states, and other stakeholders can apply for these critical grants.

These victories should mark only the beginning of lasting solutions to preserve the US migration corridors. Federal agencies, including the Departments of Agriculture and the Interior, are considering new ways to manage lands that maintain critical ecological links. In the face of climate change, maintaining these landscape connections is more important than ever, as it helps provide greater ecosystem resilience for species that migrate between habitats.

Opportunities are growing to integrate science and effective policies to better conserve migration corridors. It is important that leaders continue to work together to design more innovative technologies, bipartisan policies, and funding mechanisms that reconnect wildlife habitats and, in the process, benefit communities, local economies, and the health of life. wild.

matt skroch supervises the The Pew Charitable Trusts’ work on wildlife migration corridors and crossings.


RulerOpinion columns reflect the views of their authors and not necessarily those of Rulerthe editors or management of .

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