Y2Y is working to improve safety for people, and connectivity for wildlife , on Idaho’s highways and roadways.    

What is the threat?

Wildlife migration and movement corridors often intersect highway corridors, creating high collision risk areas, or “hotspots,” that are dangerous places for people and wildlife.   

Idaho is the fastest growing state in the U.S., and with that growth comes increased traffic. Wildlife populations are at risk when traffic prevents animal movement. Idaho Department of Fish and Game has identified some of these at-risk areas across the state:

U.S. 20 

In eastern Idaho, Highway 20 cuts through the northwest corner of Yellowstone National Park and runs north-south along its western border. Residents, tourists and commercial traffic make the roads around Yellowstone very busy. This transportation route is also an important wildlife corridor. Animals must often cross U.S. 20 to migrate in and out of the park and move across the region.  There have been many documented deaths of animals such as grizzlies, elk, bison, moose and wolves due to collisions with vehicles on this highway.   

U.S. 95 

In north Idaho, Highway 95 bisects the McArthur Lake Wildlife Management Area, in wildlife corridor used by deer, elk, moose and bears. The highway’s design also makes it dangerous for drivers, and is a spot has seen a number of fatal collisions. 

State Highway 21 

Highway 21 near Boise, Idaho, is crossed by about 50,000 deer and elk who migrate every year. In the past on an 11-mile (18-kilometer) stretch of Highway 21 close to Boise as many as 200 deer are hit and killed by vehicles each winter. In 2010, an underpass was built nearby, and the first year after its completion, there was only one reported wildlife vehicle collision in that section of road. Less than two miles (3 km) away, plans are in motion to build Idaho’s first wildlife overpass. 

Highway 30 

In southeast Idaho, near the town of Montpelier, thousands of deer cross Highway 30 at Rocky Point, and more than 100 are hit each year.  

Moose often cross Idaho highways, especially at dawn and dusk, when they are much harder to see. Photo: Shutterstock

What is the opportunity? 

Now is the perfect time for Idaho to make mitigation for wildlife a priority in the project’s initial planning, budgeting and engineering process. Idaho, and almost every other state with the Rocky Mountains, are building wildlife accommodations that save lives, money and wildlife populations. 

Wildlife crossings with fencing have reduced wildlife-vehicle collisions by up to 90 per cent and are the most effective way to address the issue.

In 2018, Idaho Department of Fish and Game released a migration corridors action plan pinpointing five priority migration corridors in Idaho. A primary threat to each of these corridors is busy highways and includes the four projects listed in the section above. The action plan spells out direction for Idaho to research and mitigate some of these areas. 

What are we doing? 

It’s important to Y2Y to protect both the people we love and Idaho’s wildlife, an integral piece of the state’s economy and cultural identity.   

In eastern Idaho, Y2Y is commenting on proposed highway expansions into Yellowstone National Park, recommending ways to address threats to wildlife movement along Highway 20.

In north Idaho, Y2Y raised public awareness about the McArthur Lake project and submitted comments about the design of a bridge replacement at McArthur Lake that will make the bridge safer and allow big game to pass underneath. Additionally, Y2Y provided engineering expertise and has committed to help the project meet standards that can turn a bridge replacement into an effective wildlife crossing, too.

Near Boise, Y2Y has partnered with the Idaho Transportation Department and many other sportsman and conservation partners to fund Idaho’s first wildlife overpass, which will be built in 2022.


“This is an opportunity to make Idaho’s roads safer not only for drivers but wildlife, too, all while preserving our state’s economic and cultural heritage. Let’s make our roads safer, together.”   

— Kim Trotter, U.S. Program Director   

We continue to work with local partners to identify: 

  • known crossing points for moose and migrating elk 
  • known hotspots for wildlife-vehicle collisions 

What you can do

Let the Idaho Transportation Department and Idaho Department of Fish and Game know that you value safe roads and abundant wildlife populations, and that safe roads are good for Idahoans and our economy. 

Join our email list to get action alerts that will help promote safe roads in Idaho. 

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Header photo: a bear runs across a busy road, Kent Nelson