LOS ALTOS, Calif. (KGO) -- A family of mountain lions is forcing the temporary closure of the popular Rancho San Antonio Open Space Preserve on the Peninsula.
A visitor recently caught the cougars on-camera. Three were recorded walking along a trail.
"We believe there's a mother lion with three adolescent cubs who live in or near the preserve," Leigh Ann Gessner told ABC7 News.
Gessner is a Public Affairs Specialist with the Midpeninsula Regional Open Space District (Midpen).
The district initially shut down a few trails to establish a safe distance between the pumas and people. However, after additional encounters, Midpen expanded the closure to include the entire park.
"We have proactively closed the preserve so that we can proactively work with California Department of Fish and Wildlife to work with these lions to instill a little bit of fear in them," Gessner explained. "For the safety of the lions and preserve visitors."
"We're just trying to give the cats a break and the people a break for a while," a Park Ranger told drivers on Friday afternoon.
People who pulled in to the main entrance were met with rangers, redirecting them away from the closed preserve.
Mountain View resident Sungwoo Kim said he runs trails within the preserve at least five days a week.
"It's very busy. This place surprises me," he said. "Even on the weekends, I come here at 7 am and the parking lot is full."
"Always people here," Kim continued. "From trail runners, to just hikers, to families. It's interesting, you see different types of people in the mornings and the afternoon."
Midpen said Rancho San Antonio is the busiest of the 26 open space preserves it manages.
Visitors said area wildlife adds to the activity.
"I've seen bobcats with their teeny-tiny tails. I've seen deer, rabbits, snakes, tarantulas, all kinds of fun stuff," Matt Ringer told ABC7 News. "But never a mountain lion, and frankly, I'd be good if I never saw one."
Ringer is now a Colorado resident, but spent decades down the block from the preserve.
"I grew up running here, for years," he said. "And I've never seen this before."
"I think it's all really cool that they're doing this, and God knows I don't want to be around with anything that has to do with mountain lions," Ringer added. "So, let them have their time."
Midpen is working on it. The district hopes to restore what they call "balance" within the busy preserve.
"Fish and Wildlife has put a few deer carcasses out in the preserve, hoping that the mother and cubs will come to that," Gessner told ABC7 News. "To draw them deeper into the preserve."
She explained, "Once that occurs, Fish and Wildlife will implement some humane measures to try and basically instill some fear of people in the mountain lions."
Gessner assured the effort would not include anything that might harm the family of mountain lions.
She explained lions need very large habitats, and added, "Their habitats are getting hemmed in by development and by roads. So, this mother and her cubs have been pushed to the edge of open space."
The temporary closure is intended for long-term safety.
It's unclear when the preserve will reopen to the public. Meantime, Midpen is encouraging people to visit other open spaces.