$350 million of Biden’s INVEST in America Act isn’t for people. It’s for wildlife that needs help crossing the road. By Ben Goldfarb Nov 12, 2021, 10:00am EST
Fifty miles east of Seattle, a bridge crosses a steep stretch of Interstate 90 known as Snoqualmie Pass. This is no ordinary bridge, meant for automobiles or pedestrians. Covered in topsoil, boulders, and seedlings, it is intended to convey wild animals from one side of the highway to the other — and it’s working.
Since 2018, when the bridge opened and the first animal, a coyote, scampered over the six lanes below, the structure has carried creatures as large as elk and as small as toads. And it should attract even more users as the seedlings grow into trees and animals acclimate to its presence.
“As we get more shade, it’s going to be different,” Patty Garvey-Darda, a Forest Service wildlife biologist, told Vox during a recent visit to Snoqualmie Pass. “Hopefully someday we’ll see the exact same species up here as we see in the forest.”
The Snoqualmie Pass bridge is one example in a broader category of infrastructure, known as wildlife crossings, that help animals circumvent busy roads like I-90. Crossings come in an array of shapes and sizes, from sweeping overpasses for grizzly bears to inconspicuous tunnels for salamanders. A body of research demonstrates that crossings can reconnect fragmented wildlife populations while protecting human drivers and animals alike from dangerous vehicle crashes. “This structure is paying for itself because of the accidents we haven’t had,” said Garvey-Darda, as trucks roared by 35 feet below.
The construction of such crossings has never been more urgent. Roadkill rates have risen over the past half-century; today, around 12 percent of North American wild mammals die on roads. And new satellite tracking and genetic technologies have revealed subtler harms. Busy interstates prevent herds of elk and mule deer from migrating to low-elevation meadows in winter, occasionally causing them to starve. In California, freeways have thwarted mountain lions from mating, leaving the cats so inbred that they’ve fallen into an “extinction vortex.” Wildlife crossings allow animals to find food and each other across sundered landscapes and help them access new habitats as climate change scrambles their ranges.