Road safety and habitat connections
Landscaped bridges give animals a route over busy roads without entering traffic. California already has dozens of completed wildlife crossings and dozens more being planned, according to a Wildlands Network database.
Colin Reynolds, senior adviser for the Northwest Field Conservation Program, told The Center Square that roads and development divide habitat, limiting animals' access to food, mates and suitable places to live. He said some crossings elsewhere in the country have been associated with reductions of 90% to 95% in wildlife-related traffic incidents. He also cited road safety and lower insurance costs as benefits.
The California Wildlife Board identifies deer, mountain lions, elk, bears, skunks, raccoons and opossums among the animals most frequently struck on the state's roads. Collisions with larger animals pose the greatest danger to people.
Rebecca Fris, deputy executive director of the California Wildlife Conservation Board, told The Center Square that the board has directed $130 million toward crossing planning and development over the past several years. Many projects remain planned but unbuilt, she said, and more public and private funding would help carry them out and develop new ones.
Reynolds described support for crossings as spanning party lines nationwide. Assemblymember Laurie Davies, R-Laguna Niguel, objected specifically to using gas tax revenue for them. The Assembly Transportation Committee vice chair said she has opposed every effort to shift that money from pothole repairs to animal crossings, arguing that doing so breaks promises to voters. She called it "a slap in the face to Californians."
Agoura Hills crossing nears December opening
Construction is nearly finished on the Wallis Annenberg Wildlife Crossing, which spans 10 lanes of Highway 101 in Agoura Hills in Los Angeles County. Its scheduled opening to wildlife is Dec. 2, 2026, according to the Los Angeles Times.
The project's website reports that taxpayers paid $77.7 million and private donors contributed another $37.2 million. Separately, the Times reports a current project estimate of $114 million, compared with an original estimate of about $92 million to $93 million.
The opening was originally targeted for late 2025. The Times attributes the delay partly to record rainfall during the winter of 2022-23, when the construction trench flooded.
On Feb. 2, 2026, Gov. Gavin Newsom announced an $18.8 million allocation from the California Transportation Commission through the Environmental Enhancement and Mitigation Program. His office characterized the money as the final funding push needed to finish construction.
The isolation of local mountain lions illustrates the habitat concerns behind the project. Seth Riley, wildlife branch chief for the Santa Monica Mountains National Recreation Area, told the Times that close relatives accounted for 41% of documented mountain lion matings in the study area since 2002. If inbreeding begins to impair reproduction, modeling indicates an "essentially a 100% chance of extinction" for the isolated Santa Monica Mountains population within 50 years, he said.
Desert grants advance two planned crossings
Near Yucca Valley, two proposed bridges over State Route 62 would link habitat in the San Bernardino and Little San Bernardino mountains, including Joshua Tree National Park. The Mojave Desert Land Trust says three grants will take the projects to 65% design completion: $5.5 million awarded by the Wildlife Conservation Board in February 2026, a $512,000 matching grant from the Coachella Valley Mountains Conservancy and an earlier $100,000 contribution from Caltrans District 8.
The conservancy and land trust announced the planning funding earlier this year. The $512,000 comes from Proposition 4, the $10 billion bond measure approved by California voters in 2024.
The land trust also reported that a vehicle killed an 18-month-old mountain lion on State Route 62 in April 2026 as it traveled from the San Bernardino Mountains toward Joshua Tree National Park. The animal belonged to the San Gabriel-San Bernardino Mountains population, which was listed under the California Endangered Species Act in February 2026.
The $5.5 million award was part of a broader grant package approved by the Wildlife Conservation Board on Feb. 27, 2026. According to California Department of Fish and Wildlife News, the board approved $59,642,096 for 27 projects in 18 counties. That package also provided $4 million to the Temecula-Elsinore-Anza-Murrieta Resource Conservation District, in cooperation with The Nature Conservancy, for further design work on an Interstate 15 crossing in western Riverside County.
Neither the Coachella Valley Mountains Conservancy nor the Mojave Desert Land Trust responded to The Center Square's requests for comment.
Bond funding and state requirements
Proposition 4 also supports a Bay Area project combining a wildlife undercrossing beneath Highway 17 with 2.1 miles of Bay Area Ridge Trail. The State Coastal Conservancy authorized a grant of up to $4 million to the Midpeninsula Regional Open Space District for the project in unincorporated Santa Clara County. Its estimated total cost is $35,969,000.
The bond covers more than wildlife projects. A 2025 Legislative Analyst's Office report lists its intended uses as safe drinking water, wildfire and forest resilience, clean energy, nature-based climate solutions, parks and outdoor access, extreme heat mitigation and agriculture.
Two state laws also guide wildlife connectivity efforts, according to the Mojave Desert Land Trust. The 2024 Room to Roam Act directs cities and counties to address wildlife connections in land-use plans and promote safe movement through fragmented habitat. The 2022 Safe Roads and Wildlife Protection Act requires state agencies to address barriers to animal movement and give crossings priority in transportation projects.
Democratic lawmakers serving on transportation and wildlife-related committees had not responded to The Center Square by its Friday publication deadline. The Department of Transportation, California State Transportation Agency and California Transportation Commission did not make anyone available for questions that day. The California Department of Fish and Wildlife also did not respond.
