Wildlife-safety fence lines both sides of the 241 Toll Road south of The 91 Freeway in Anaheim, CA, on Tuesday, June 25, 2024. The fence is 10-12 feet high, with an 18-inch “outrigger” to prevent animals from climbing over, and is buried 2 feet deep to deter digging. While a massive wildlife bridge is being built across the busy 101 Freeway at a cost of $92 million, some scientists say there is a better — and cheaper — way to stop animal roadway carnage.
He pointed to a 6 1/2-mile fencing project on both sides of the 241 Toll Road in Orange County, stretching from the 261 Toll Road north to the 91 Freeway near Yorba Linda/Anaheim Hills as a model for fencing that saves the lives of mountain lions in the Santa Ana Mountains. The Wallis Annenberg Wildlife Crossing in Agoura Hills, under construction and set to open in early 2026, will span 10 lanes of the 101 Ventura Freeway at Liberty Canyon Road. “The bridge will allow for wildlife to cross freely over the 101 freeway without the threat of death or accidents, and will ensure the survival of many isolated species,” states the official website.
The crossing developers will build tree-and-shrub entryways leading to the bridge entrances. And the bridge itself will be covered in soil, grasses, trees and greenery to lure cats into thinking it is an extension of the rural hillsides on each side of the freeway. While Shilling supports more wildlife crossings and underpasses, he said the better solution for reducing roadkill is to erect fences near roadways. But in the case of the Santa Monica Mountains, that would keep the isolated mountain lions from reaching the other side, negating the purpose of enhancing healthy breeding.
He said wildlife crossings and fencing can work in tandem. Often fencing can lead mountain lions to the wildlife crossings, whether under or over a freeway. He’s advocating for more fencing along Ortega Highway and on other parts of the 241 toll road, where mountain lions cross and get killed. The state is far behind other states in supplying funding for fencing and for wildlife crossings to protect mountain lions and other wildlife habitat dying at alarming rates from vehicle strikes, Shilling said.