As a Santa Barbaran with family in Los Angeles, I am occasionally among the 300,000 cars per day zipping through Agoura Hills. Vehicles traveling US 101 now observe a “bridge to nowhere” emerging from an oak-filled canyon among greening hills.

The construction zone is the Wallis Annenberg Wildlife Crossing at Liberty Canyon Road. On completion, it will be the largest wildlife crossing in the world, as well as the first between two major ecosystems and the first over a major California freeway.
 
The crossing caps 40 years of effort since wildlife enthusiasts recognized the fragmentation of wildlife habitat between the Santa Susana Mountains, the Simi Hills, and the Santa Monica Mountains. The initial step, in 1990, was creating the Santa Monica Mountains Conservancy.
 
The conservancy designation allowed time to systematically acquire private land with voter-approved funds. Private and public and groups including Wallis Annenberg, Caltrans, the National Park Service, the National Wildlife Federation, and several Santa Monica Mountains groups permanently protected this critical habitat within one of 36 global biodiversity hotspots.
 
Since that insightful move decades ago, the surrounding area has become more urbanized. Cougars, which can leap 40 feet across and up to 17 feet high, are no match for US 101 traffic, now 10 lanes wide in many places.

These majestic and reclusive animals, which require a home range of 50-150 miles, already have suffered major genetic declines due to low populations and inbreeding. (The home range of cougars is 50 square miles for females, 100 square miles for males).
 
One cougar may be credited with bringing the project iconic status. P-22 was a celebrity in life, making cameo appearances on motion detector cameras at residences in Silver Lake and Los Felix.

These cities are adjacent to Griffith Park, where P-22 made his home for 10 years on the smallest home range ever recorded for an adult male mountain lion.

P-22 was euthanized Dec., 17, 2022, after suffering traumatic injuries consistent with being hit by a car.
 
The Wallis Annenberg Wildlife Crossing aims to reverse this habitat fragmentation for cougars, as well as mule deer, bobcats, coyotes, western toads, desert cottontails, gopher snakes, and countless critters that form the ecosystem.

A successful crossing will bolster the idea that humans can coexist with wildlife.
 
Decades of collaring cougars and other wildlife have established where animals approach the freeway to cross. Wildlife research also revealed how to plan a safe, sustainable wildlife crossing, allowing their movement and the exchange of genetic material.
 
Beth Pratt, the National Wildlife Federation’s regional director and the “driving force” behind the #SaveLACougars fundraising campaign, says, “It’s a difficult space. It’s angled; there’s a slope that is … tricky because if it’s too steep, animals won’t use it.”

The design mitigates these issues and includes strategic rock placement to abate freeway noise and light pollution.
 
The one-acre bridge will measure 174 feet wide and 210 feet long, spanning both the freeway and nearby Agoura Road.

The crossing is designed to be large enough that wildlife won’t notice they’re on a relatively narrow passage. An approach area of 10 acres on either side of the bridge will contain “a plant palette that is advantageous for individual species,” according to Robert Rock, Living Habitats CEO.

Locally native species have been collected for several years. Within two to five years, Rock says, the habitat will become self-sustaining.
 
Wildlife are expected to find the bridge within a couple weeks of its opening. Cougars will take longer to explore the new habitat.

In the meantime, we can all play a part in protecting cougar habitat. The most important for most of us is refraining from placing mouse or rat bait outside our homes, wherever we live. Rats and mice bring poison back to their nests, die, and poison other wildlife who eat their carcasses.
 
If you’re driving in the early morning or dusk, drive slowly enough to avoid wildlife attempting to cross roadways. Researchers believe 70-100 cougars are killed each year by car strikes in California. My husband nearly hit one recently one pre-sunrise morning just below Parma Park.
 
For a fascinating tour, check out the Wallis Annenberg Wildlife Crossing as it progresses, and visit 

In the meantime, we can all play a part in protecting cougar habitat. The most important for most of us is refraining from placing mouse or rat bait outside our homes, wherever we live. Rats and mice bring poison back to their nests, die, and poison other wildlife who eat their carcasses.
 
If you’re driving in the early morning or dusk, drive slowly enough to avoid wildlife attempting to cross roadways. Researchers believe 70-100 cougars are killed each year by car strikes in California. My husband nearly hit one recently one pre-sunrise morning just below Parma Park.
 
For a fascinating tour, check out the Wallis Annenberg Wildlife Crossing as it progresses, and visit SaveLaCougars.org and look for their section describing their tours.