. >> reporter: nancy vandermay and eric barkolo moved here to be close to wildlife and got their wish in the form of a mountain lion named p-41, who seems to love their back yard deck. he's right out here where we are? >> >> reporter: he has come to visit at least ten times. triggering security cameras taking both video and still pictures. the area is called cougar canyon. what else? >> here he is just literally made a loop around our house for some reason. >> yeah. >> reporter: like proud parents with baby pictures they show off their video scrapbook. >> and let me point out how his paws are on the wood and not on the gravel so he can make as times. >> reporter: camera technology has revolutionized the way mountain lions and other wild animals are studied. joanna turner is a sound effects editor for universal studios. on her own time she's one of several citizen scientists, as they're called, who put remote cameras up in the wild hoping to get that perfect shot. >> t h >> how do you know where to look? >> we look for tracks and we look for signs of them and we look for deer because t