What You Need to Know About the World’s Largest Wildlife Crossing

Driving north on Highway 101 from downtown Los Angeles, you can’t miss a massive overpass that goes up Agoura Hills. Construction on the bridge, spanning 10 busy lanes, began two years ago and won’t be finished for at least another year.

But unlike most road infrastructure projects, this one isn’t for cars or pedestrians. The crossing is a wildlife crossing, intended to provide safe passage through a Southern California landscape crisscrossed by major roadways, allowing mountain lions, coyotes, deer, snakes, rabbits and butterflies to move more freely and safely, said Beth Pratt, California regional director for the National Wildlife Federation.

“It’s more than just a bridge — it’s a climate resilience project that’s necessary if the ecosystem and all the life within it are to have a chance in the future,” Pratt, whose group led the campaign for the crossing, told me.

The Wallis Annenberg Wildlife Crossing, as it’s called, is expected to be completed in 2026 to connect the Santa Monica Mountains and the Simi Hills. It’s a $92 million project — with $58 million from the state and the rest from philanthropy — and would be the largest wildlife crossing in the world. The hope is that the crossing will reduce collisions between wildlife and vehicles and allow animals to roam more widely in search of food, shelter and mates, officials say.

“With projects like these, we connect and restore habitats so future generations can continue to enjoy California’s unparalleled natural beauty,” Gov. Gavin Newsom said in a statement earlier this year.

More than a million wildlife-vehicle collisions occur in the United States each year, resulting in tens of thousands of human injuries and hundreds of human deaths. As a result, wildlife crossings have become increasingly popular in the United States in recent years, with environmentalists and transportation officials agreeing on their benefits.

The new crossing in Agoura Hills will be huge — 200 feet long and 165 feet wide — and will be planted with native vegetation that blends in with the surrounding landscape, with tall trees and walls covered in thick vegetation to block out the noise of cars speeding by. People will not be allowed to use the crossing, and officials will be monitoring it to make sure, Pratt told me. (She said planting poison ivy would be a backup plan to deter people.)

The bridge will help all kinds of animals: a barn owl has already been spotted trying out the span — but the first target is mountain lions.

According to the Road Ecology Center at the University of California, Davis, more than 600 cougars were killed by vehicles in California between 2016 and 2023. Last month, a cougar was found dead on the 101, less than a half-mile from where the crossing is being built. Another was found over the holiday weekend dead on the 405.

The busy freeways of Los Angeles have cut through the territories of these big cats for decades, often forcing them to run across the lanes or confine themselves to a small patch of land with few potential mates. This leads to inbreeding and dangerously low genetic diversity, putting them at risk of extinction.

In particular, it was P-22, a cougar turned Los Angeles celebrity, who brought the species’ plight home to Los Angeles residents. P-22 braved the 101 to reach Griffith Park, but became isolated there and was unable to find a mate. He was euthanized in 2022 after being struck by a vehicle.

The wildlife crossing is an expression of a new vision of conservation: animals don’t need any refuge to survive, but should be able to move freely through their habitats, Pratt said.

“Almost everything in this ecosystem is affected by this impenetrable wall,” she told me. “We now know that nature needs movement. Nature needs to be connected.”

And before you go, some good news

Michelle Navarro and Christopher Zegunis met in 2016 at a magic class in Los Angeles. Learning and performing tricks together, “infatuations developed,” Navarro said.

At the end of the course, Zegunis invited her to dinner and the pair hit it off, bonding over their shared love of Disneyland and helping each other through times of grief and the coronavirus pandemic.

After three years of living together and a false start, Zegunis proposed at Disneyland, surprising Navarro during a planned photo shoot.

They married in June in Hawaii, a special place for Navarro.

Read the full story in The Times.