COUGARS have long been the bane of ranchers whose livestock may be at risk, but mountain lion-human interactions may be on the rise on the front range of the Rockies, according to James Halfpenny of the Institute of Arctic and Alpine Research here, especially in Boulder County.The risk of attack is small and confrontations need not be dangerous, experts say, if humans behave appropriately when a mountain lion is in the neighborhood. "In 1967 cougars became game animals and so were protected," Dr. Halfpenny says. "They could not be shot as varmints. " The population of cougars (also called mountain lions, pumas, or panthers) has grown dramatically across the front range, principally because deer are plentiful and cougars are protected, Halfpenny says. Various municipalities and private landowners have banned deer hunting, and the ungulates roam freely into suburban neighborhoods in Boulder County, feeding on lawns and ornamental shrubs. Where deer go, lions follow. At the same time, the human population in the area skyrocketed, threatening lion territory. Pets and pet food as well as barbecue grills attract lions. "There are more deer in places where they didn't used to be, and more people in those same places," says Colorado State Division of Wildlife biologist Kathi Green. "Subdivisions built in prime deer range are an invitation to problems. As more people spend more time outdoors and in the foothills where so much recreation activity happens the possibility of coming across a lion is greater." Eyewitness accounts of lion behavior around humans may suggest lions are habituating to people, but there is no scientific research evidence yet to confirm that suspicion, she says. Sightings of lions have increased over the last 10 years all across the Western United States. There have been 50 attacks (10 of which were fatalities) in the last 100 years - but more than half that number happened in the last 20 years, says Ms. Green. Halfpenny points out that early in the century the deer had been market-hunted out and so there was no prey base for the lions. Any lion seen was killed, too. The fatal attack on a jogger last January in Idaho Springs, Colo., focused public attention again on the mountain lions. Over 200 experts from 13 Western states gathered in Denver for a Mountain Lion-Human Interaction Symposium in April. Halfpenny pointed out that lion-human contact was inevitable under present conditions, and other researchers stressed the need for educating mountain residents and visitors to the lion's ways. "If a lion is running down a subdivision road every week, we try to do an education outreach to tell the people what to do and not to do and see where they keep their pets and what they can do to reduce whatever attraction there is for the lions," she says. Still, people like to feel in control of their environment. So, public attitudes range from "No lion should be killed for any reason" to "lions should be hunted out wherever lion-human conflict could arise." Between 1,500 and 3,000 cougars roam the state of Colorado, according to Green, though no thorough studies have ever been made. The hunter harvest is about 180 lions a year in Colorado, and pumas are in no danger of extinction in this part of the country. Only the Florida panther is on the endangered species list. Not much is known about panther behavior in relation to humans because attacks are rare. But wildlife experts agree that anyone who meets a lion should not run. "Remember that every lion is different," Green says. "It's a good idea to carry a big walking stick, make noise, and make sure your children stay close to you in lion country. Teach them what to do if they should encounter a lion. We tell people never to approach a lion - especially one that is feeding or has kittens. Give them a way to escape, because most of the time a lion will try to avoid confrontation. If the lion won't leave, move or back away slowly. Be calm, do all you can to appear larger, sta nd upright. Pick the children up. "If the lion behaves aggressively, throw sticks or stones - whatever you can get your hands on without crouching or turning your back. Wave your arms slowly and speak firmly, with authority. What you want to do is convince the animal you are not prey and may in fact be a danger to it. Don't yell, be calm."