By Rachel Becker, CalMatters

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Just weeks after a mountain lion wandered into San Francisco, state officials voted to permanently protect populations of the charismatic predators that prowl the coastal mountains between the Bay Area and the Mexican border. 

Mountain lions are one of the last big predators keeping ecosystems in balance. They feed on deer and other animals, leave scavengers, raptors and other wildlife the remains, and help maintain equilibrium among plants, prey and predator. 

But, caged by concrete, killed by cars and sickened by rat poison, the isolated mountain lions along California’s coast risk inbreeding themselves into extinction, scientists and state wildlife officials say. 

Members of the California Fish and Game Commission on Thursday voted unanimously to list six groups of Central Coast and Southern California mountain lions as threatened under the California Endangered Species Act. 

These mountain lions account for about one-third of the roughly 4,200 solitary, tawny cats thought to roam California. 

Dozens of people spoke before the board today, from ardent supporters of wildlife to fierce opponents of free roaming predators and residents of rural areas concerned for their livestock and livelihoods. 

Listing the mountain lions aligns with the state’s existing ban on hunting mountain lions for sport and prohibits harming, or “taking”, them except with a permit under certain conditions. It could also increase their priority for limited conservation grants and other funds. 

More importantly, advocates say, it will trigger habitat protections — including under the landmark California Environmental Quality Act. 

Builders push back 

State and local planning agencies must determine whether projects such as new roads, buildings or other developments could harm protected species and their habitats, and require developers to reduce that harm when possible.

For mountain lions, advocates and scientists hope that the listing will reduce further habitat loss and fragmentation in areas already carved into isolated pockets by roads and cities. 

“If we want to maintain mountain lion populations in these coastal regions, then we've got some work to do,” said Chris Wilmers, a professor of wildlife ecology at the University of California, Santa Cruz and lead investigator of the Santa Cruz Puma Project.

Builders have challenged some of the details of the listing, but did not oppose granting the mountain lions protected status. 

In a letter, the California Building Industry Association and the Building Industry Association of Southern California warned that the state’s current habitat maps could force developers in urban areas into studies and mitigation efforts that “would significantly increase project costs and schedules.” 

Protecting mountain lions is a card that one wealthy Bay Area enclave has already tried to play in a gambit to block denser housing — to the scorn of housing and wildlife advocates alike. 

Conflict over wildlife conflict

Ranchers and residents of hilly, remote Bay Area and Central Coast suburbs also argued that more protections could spur more mountain lion attacks on people and livestock, and harm ranchers’ livelihoods. Some sent the commission photographs of mauled cattle. 

“People have them on cameras all the time eating house cats off peoples' porches, dogs dragged off in broad daylight right in front of their owners, and children being mauled,” Greg Fontana, whose family has ranched the coastal reaches of San Mateo county for generations, wrote in a letter to the board. 

It’s rare for the reclusive cats to attack people — rarer still for the attacks to be fatal. Cougars are known to have killed six people in the last 136 years — most recently a young man in 2024 in El Dorado County, outside the area where mountain lions are now listed as threatened.

Attacks on livestock and pets, however, have trended upward in recent decades, according to a state report. But state wildlife officials also note that such attacks rise for every mountain lion killed or relocated in the prior year. One theory is that younger males move into the emptied territory, where the less proficient hunters go after slower pets and livestock. 

Listing mountain lions under the state’s endangered species act doesn’t prevent wildlife officials from intervening in conflicts, either, according to Stephen Gonzalez, a spokesperson for the California Department of Fish and Wildlife. The act still allows the department to “issue permits for take of a … listed species for ‘management’ purposes,” which could include managing mountain lions that kill pets and livestock. 

Mountain lions have had temporary protections under the state’s endangered species act while the state weighed whether to list them. Even in that time, Gonzalez said the department has issued such permits to scare off troublesome mountain lions. It “anticipates it will continue to do so … evaluating each situation on a case-by-case basis and continuing to prioritize non-lethal methods.” 

Inbreeding to extinction

Scientists and advocates say that mountain lions are running out of time: physical signs of inbreeding, including kinked tails, testicular defects and malformed sperm, have already cropped up in cougars corralled by freeways in the mountains of Southern California. 

Having a kinked tail, where the end is sharply bent like an ‘L’, doesn’t seem to harm a mountain lion, Wilmers said. But they’re an ominous sign that a population is reaching alarming levels of inbreeding. Without fresh gametes swimming in the gene pool, the iconic cougars of the Santa Ana and Santa Monica mountains risk dying out in the coming decades when inbreeding starts affecting reproduction and survival, scientists warn.  

Even populations further north are struggling to find mates that aren’t related to them.

Wilmers recalls the first time he saw a kinked tail on a trail cam in the Santa Cruz mountains. “It was definitely an ‘Oh shit’ moment,” Wilmers said. “This is really happening.” 

To combat the array of threats — from inbreeding and car accidents to rat poisons and wildfires — the Center for Biological Diversity and the Mountain Lion Foundation petitioned in 2019 to add Central Coast and Southern California Mountain Lions to the state’s endangered species list. 

“These populations are facing an extinction vortex,” said Tiffany Yap, urban wildlands science director at the Center for Biological Diversity. “We need these protections to get more connectivity on our roads, in our development, so that they can roam freely.” 

More than six years later, the California Department of Fish and Wildlife agreed. In December, a staff report recommended that, with some tweaks to the protected area, California list these mountain lions as threatened. 

Room to roam

California is already taking steps to connect cougars’ habitats — sinking millions of dollars into highway crossings to give wildlife safe passage over or under the cars and trucks that scientists report killed hundreds of mountain lions over a seven year stretch. 

Yap says it’s not enough — and San Francisco’s recent visit from a cougar is a prime example. Young males disperse to find new territory and mates away from their relatives and other more dominant males. 

But without paths to suitable habitat, they can find their way to Yap’s neighborhood in Pacific Heights, where the 80-pound cat ended up sandwiched in a narrow space between two apartment buildings.  

Yap was across the street watching California Fish and Wildlife biologists and veterinarians from the San Francisco Zoo trying to catch the cougar, which they eventually tranquilized and released into the Santa Cruz Mountains. 

To her, it drove home the importance of protecting — and connecting — the mountains the lions call home.  

Wilmers agreed. “There’s always going to be mountain lions bumping into San Francisco. But right now, that’s all they can do,” he said. “We’d like to get to the place where they can find ways through this maze of urban and suburban development, to the next mountain range over.” 

This article was originally published on CalMatters and was republished under the Creative Commons Attribution-NonCommercial-NoDerivatives license.