Wildlife fencing proving to be a big success on US 97

By Mike Allende

While the I-90 wildlife overcrossing receives much of the attention when it comes to our wildlife-connectivity and safety efforts, it's not the only work we're doing to make things safer for everyone on and near our highways.

A bobcat stops for a close up while traveling under US 97 where new fencing has
helped give wildlife a safer way to cross the highway.

A big success in 2020 involved the 12-mile stretch of US 97 between Riverside and Tonasket, arguably the worst deer-vehicle collision area in the state. Running between the North Cascades and Okanogan Highlands ranges, we see all the usual wildlife you might expect and though we haven't seen them, we've heard there are rare appearances of Canada lynx, wolverine and endangered sharp-tailed and greater sage grouse as well. Oh, not to mention our state's largest herd of mule deer calling that area home. Many apple orchards in the area attract the deer and keep them close to the highway, which is never a good thing as that puts both passing motorists and the deer at risk

We knew something had to be done.

Led by Conservation Northwest, we were part of a team that also included Confederated Tribes of the Colville Reservation and the Mule Deer Foundation to install about 1-mile of wildlife barrier fencing south of an existing bridge that had all the characteristics necessary to retrofit to allow the diverse wildlife in the area to safely pass underneath. The fencing installation began in October 2019 and was completed in August 2020, and our cameras monitoring wildlife movement has shown it to be a big success!

Looks like other animals are giving this cougar a clear path to cross under US 97, as area which sees a lot of wildlife activity.

In just this first year, we saw almost 2,200 mule deer crossings – about an average of six crossings a day! That's the most deer crossings we've ever documented in a single year. But it's not just deer. Everything from cougar and bobcat to raccoons to turkey and pheasant are taking advantage of the safer environment.

During this same period, we've seen a 63 percent drop in deer-vehicle collisions reported within the area the fencing lies. Because the fence was completed only halfway through the first year of monitoring, we expect to see numbers get even better. Judging by other locations, we can expect to see an 80-to-90 percent drop in deer-vehicle collisions by the next monitoring period.

Left: The US 97 corridor is home to the state's largest herd of mule deer and finding safe ways for them to cross the highway is good for both the animals and drivers. Right: It's not just large animals finding their way across US 97,
as this clan of raccoons shows.

Of course, we recognize this is just a mile of a 12-mile stretch that needs more mitigation. This likely requires building several new wildlife underpasses and connecting them with fencing, which all requires funding. While simply putting up fencing to keep wildlife from the highway may reduce collisions in the short term, it goes against our long-term goal of increasing wildlife habitat connectivity and avoiding the creation of new barriers to wildlife movement. We want to provide a safe travel corridor for both animals and drivers, and create an environment for our animal friends to be able to thrive.