Speed Reads

real life animal crossing

The world's largest wildlife crossing is now being built in California

Spanning 10 lanes of Highway 101, the Wallis Annenberg Wildlife Crossing aims to change the fortunes of mountain lions and other animals living in the Santa Monica Mountains.

Last week, crews started breaking ground on the $87 million wildlife crossing in Agoura Hills, California, and once it's completed — the goal is by 2025 — it will be the largest such corridor in the world, CBS News reports. The 165-foot-wide crossing will connect the Santa Monica Mountains with the Simi Hills, about 10 feet above the freeway. To make sure animals use the crossing, it will be surrounded by trees, bushes, and sound barriers, so the cars and traffic below don't scare creatures away.

The National Park Service spent 20 years studying the animals in the Santa Monica Mountains, and found that urban development has genetically isolated mountain lions in the region; researchers estimate that the animals will become extinct within 50 years unless there is an influx of genetic diversity, CBS News reports. Freeways not only keep mountain lions from roaming, but are also extremely unsafe, as many mountain lions are hit by cars and killed while trying to cross them.

This is the first crossing of its kind in an urban area, Beth Pratt, regional executive director of the National Wildlife Federation, told CBS Los Angeles, and with its special design considerations and use of living trees and plants, the corridor is "an engineering marvel."