The last one was in 2015, but before then, one hadn't been spotted in the area for more than 100 years.
Over the last week, Salesforce CEO Marc Benioff posted two surveillance videos of a mountain lion strolling by.
Despite the camera sightings, the Presidio Trust said their motion activated wildlife cameras haven't captured a picture of the mountain lion but noted there have been two reported sightings in the last few days.
The first was Monday in Pacific Heights, near the Presidio, and the other on Wednesday in the parking lot of China Beach near the southern end of the park.
There are already coyote warning signs.
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"Now they need the mountain lion warning signs," said neighbor Pam Feldman.
The California Department of Fish and Wildlife tells ABC7 News it's unusual to have a mountain lion in the city limits of San Francisco, it's not as surprising to see one near the rugged, natural, open areas in the Presidio. A mountain lion's home range can stretch up to 400 square miles.
Officials say it's possible the lion wandered to the city from the South Bay or the Peninsula.
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Nancy Foster, who lives in the neighborhood, said she thinks she heard the mountain lion attacking a coyote the other night.
She says she heard "whimpering and crying (that) went on for a very long time."
"My instinct was it had been attacked," said Foster.
Fish and Wildlife officials say a mountain lion's favorite food is deer, of which there is a high population in the Bay Area.
Feldman, who walks the Presidio every day, says she hopes she doesn't run into the neighborhood's newest visitor.
"It would be scary," she said.
Officials suggest talking or singing while on the trail to make your presence known. If you do come face to face with a mountain lion, wave your arms, make loud noises and never run away.
They also say mountain lion attacks on people are extremely rare.
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