These large cats roam throughout the west, and lately have been causing problems in urban areas. Increased attacks on humans and pets most likely are because of civilization's encroachment into habitat normally occupied by lions. In the Yellowstone area, mountain lions, also known as cougars, are residents of the backcountry and are rarely seen. These predators may weigh up to 170 pounds and reach lengths of eight feet from nose to tail. Males are larger than females.
Lions are meat-eaters and prefer their menu fresh.
Deer are among their favorite prey species, but they'll also catch other animals such as beavers, rabbits, porcupines and various rodents. Contrary to popular belief, lions do not ambush their prey from a tree limb as the hapless quarry walks underneath. Instead, the cat makes an incredibly stealthy stalk, using vegetation as screening cover. When it's just a short distance away, the lion makes a quick charge and either catches the prey in the first few bounds or misses it. During long chases, deer can usually outrun a lion, but the Initial surprise attack is a most successful strategy.