SAN MATEO — A slinking feline photographed Sunday evening in San Mateo was not a fearsome mountain lion but, in the words of Tweety Bird, just a little old “puddy tat,” according to wildlife officials.

A concerned resident spotted the animal around 8 p.m. on 20th Avenue, in a mostly residential area just east of Alameda de las Pulgas, and called the police. Officers told neighbors to go indoors and “shelter in place” while they set up a perimeter. They looked for about an hour but did not find the elusive cat.

Police called in the California Department of Fish and Wildlife, which sent wildlife officers to the scene Sunday night. The officers analyzed the resident’s photo of the cat walking beneath a sign on a wall outside The Gardens, a condominium complex.

The wildlife experts determined the sign was just 2 feet wide. The size of the cat relative to the sign ruled out a mountain lion and pointed to a regular domestic cat, said Fish and Wildlife spokesman Steve Gonzalez.

“It kind of gives you perspective on the size of that cat,” said Gonzalez, adding, “It’s better to be safe than sorry. So for the San Mateo Police Department to be cautious is always good.”

The area where the cat was seen, at the intersection of 20th Avenue and La Salle Drive, is just east of the Peninsula Golf & Country Club and a block from Serra High School.

It would not be extraordinary for a mountain lion to stray into the heart of San Mateo. Last May, Fish and Wildlife officials tranquilized and relocated a cougar that was found at the intersection of El Camino Real and Ninth Avenue.

San Mateo police Sgt. Richard Decker said mountain lion sightings have been fairly common in the summer during the drought. Cougars leave the sanctuary of the Santa Cruz Mountains as they follow deer that are searching for water sources, he said.

“Anytime we see a shortage of water or a drought they tend to come down from the highlands,” he said.

Residents should be vigilant and let authorities know if they see anything consistent with the presence of a mountain lion, such as a deer carcass. Experts say to avoid hiking or jogging in wooded areas at dawn, dusk or night, and to keep a close watch on children when visiting mountain lion habitat.

If you encounter a mountain lion, do not run. Instead, experts say, you should face the animal, make noise and try to look bigger by waving your arms. You may throw rocks or other objects to scare it off. Make sure to pick up small children.

Contact Aaron Kinney at 650-348-4357. Follow him at Twitter.com/kinneytimes.

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