A camera trap stationed on the nearly finished wildlife bridge over Route 97 in Siskiyou County captured images of three mule deer crossing the structure within the last few days, officials said. The $20 million overpass, built by the California Department of Transportation, is the first wildlife crossing constructed over a major highway in the state.
The bridge itself is complete and ready for use, according to Fraser Shilling, director of the Road Ecology Center at the University of California, Davis. Only final touches on the adjacent fencing remain, which Shilling said is needed to funnel wildlife toward the crossing.
“Wildlife crossings by themselves do not stop roadkill,” Shilling said in an interview. “It’s the fencing associated with them that stops roadkill.”
Caltrans district two posted a message on Facebook noting that even with construction workers still on site, wildlife had begun using the crossing. “While the contractor is still completing final touches, it’s incredible to see wildlife already embracing the new structure,” the agency wrote. “In addition to deer, a bobcat and other wildlife have also been spotted using it.”
The 2024 report co-authored by Shilling and published by the Road Ecology Center characterized vehicle crashes involving wildlife as “a damaging and preventable natural disaster.” The report found that California drivers kill nearly 50,000 mule deer annually, a figure that accounts for roughly 10 percent of the state’s deer herd. Nearly 100 mountain lions die every year in car crashes, the report said, along with thousands of other animals across a wide array of species.
At the site of the new crossing, Caltrans recorded 50 deer and 16 elk killed from 2015 to 2020.
More crossings are in development. The largest — the Wallis Annenberg wildlife crossing in Southern California — is scheduled to open at the end of 2026 and will span the breadth of the 10-lane 101 freeway, making it the largest wildlife overpass in the world.
Shilling praised Caltrans for using its own funds to build the pioneer structure over Route 97, calling the agency’s staff “heroic.”
“Within agencies like that, doing anything different means you’ve got big ovaries,” he said.