In fall of 2011, biologists Dan Cooper and Miguel Ordeñana installed 13 remote cameras in a 4,000-acre patch of wild hills known as Griffith Park, above Los Angeles, Calif. Each month, they combed through predictable images of a near-urban ecosystem: Coyotes marking, bobcats stalking, deer browsing the chaparral. One evening last March, however, they got a shock: A photo captured at 9:15 p.m. on Feb. 12 showed a large cat-like creature  ambling along a trail above the iconic Hollywood sign. There could be no doubt: It was a mountain lion. Until that moment, the only surprising sight had been the occasional homeless person. "It was like finding Bigfoot," Cooper says. "The difference being that Bigfoot doesn't exist, so you couldn't really hope for it." Griffith Park is, technically, part of the Santa Monica Mountains, which begin in slide-prone bluffs along the Southern California coast, rise to 3,000 feet and