Wildlife Crossing

The Wallis Annenberg Wildlife Crossing will officially open for business on December 2. It goes over a 10-lane segment of U.S. 101 in Los Angeles County, California. That’s one of the country’s busiest stretches of highway. Construction of the bridge began more than four years ago, on Earth Day in April 2022. The structure of the $114 million project is nearly complete.

DRONE SHOT This view captured on August 23 shows the bridge from above, covered in soil and vegetation.

Once finished, the new wildlife bridge will be the largest ever built. Bobcats, coyotes, foxes, mountain lions, and other animals will be able to safely make their way across.

UNDER CONSTRUCTION A work in progress for more than four years, the crossing nears its final stage.

A Freeway in the Way

Freeways are a big problem for wild animals. When a freeway splits a habitat, many animals can’t safely travel from one side to the other. “Without a safe and sustainable × sustainable able to be maintained (adjective) wildlife crossing, movement between these remaining areas of natural habitat is severely restricted,” reads a statement on the state of California’s official website. “Wildlife within the Santa Monica Mountains is essentially trapped.”

Jeff Sikich is a wildlife biologist × biologist a scientist who studies living things (noun) . He works for the Santa Monica Mountains National Recreation Area. Sikich leads a mountain lion study there. He told TIME for Kids that the 101 freeway “is a major barrier” for the lions. It separates those living there from those farther to the north.

EARTH DAY Reporters gather at the site of the crossing on April 22, 2026.

When animal groups remain apart for a long time, they encounter hardships. For example, Sikich says, “small populations can become less healthy because they have fewer opportunities to find mates from other areas.” Eventually, the entire population gets weaker. The new wildlife crossing will give them, and other species, a much-needed path forward.

PROWL ON Mountain lions will see separate parts of their habitat reconnected by the new bridge.

For All Animals

Seth Riley is another biologist for the Santa Monica Mountains National Recreation Area. He leads the wildlife team there. Riley says the crossing was created for all kinds of animals to use, not just the big ones. “Some of the smallest animals may do more than cross it,” he told TIME for Kids. “Lizards, insects, and small mammals might even make their homes on or near the crossing as the native plants grow.”

MORE CATS Other cat species, such as bobcats, will use the bridge too.

Freeways are busy and noisy, which scares animals away. But this crossing is covered with soil and plants. Small rock piles give animals places to hide. When the bridge is finished, it should look and feel like a natural, inviting part of the land.

LITTLE GUYS Small animals might make homes on the bridge.

Scientists will use remote cameras and GPS tracking collars to discover what animals show up. More than 50 cameras will keep watch on the crossing and the land around it. Riley remembers a small fence lizard that scrambled to the top of the crossing while it was being built. The bridge wasn’t connected to either side yet. But the lizard was already investigating. “Wildlife is often more curious and adaptable than we expect,” Riley says.

Beth Pratt of the National Wildlife Federation helped lead the campaign to build the crossing. As she told the Los Angeles Times in January, “Build it, and they really do come.”

Remembering P-22

P-22 was a famous mountain lion who lived in Griffith Park, in the middle of Los Angeles. For a decade, scientists tracked and studied him. After he died, people of all ages gathered in 2023 for a memorial (above) in his honor.

Jeff Sikich has called P-22 an “important ambassador for urban wildlife.” P-22 showed how a big cat might manage to live in a busy city, despite the many challenges. The new wildlife crossing is part of his legacy.