Mountain lion, cougar, puma, panther, catamount — same cat, different region. Puma concolor has more common names in English than any other mammal in the Americas, a side effect of having the widest north-south range of any land mammal in the Western Hemisphere. Adult toms run 120 to 180 pounds in most of the Lower 48; females are smaller, typically 80 to 120. Tawny coat, long heavy tail roughly a third of total length, black-tipped ears, and white muzzle markings. Kittens are spotted for the first few months and lose the markings as they grow.
They are obligate carnivores and ambush predators. Mule deer and elk make up the bulk of the diet in the West; bighorn sheep, feral hogs, and smaller mammals fill in where available. A lion typically kills every seven to ten days and caches the carcass under leaves, dirt, or snow between feedings. Home ranges are huge — a resident tom may defend 100 to 250 square miles. Densities are low even in prime habitat, which is why sign tells you more than sightings.
Lion hunting is legal in some western states and banned in others. California outlawed all sport hunting of mountain lions in 1990 by ballot initiative and they are a specially protected mammal there. Where hunting is permitted, methods, quotas, and pursuit rules vary widely — check your state's hunting page for what applies. The cats are recolonizing parts of their historic range east of the Rockies, with confirmed dispersers reaching the Midwest and rare records as far east as Connecticut.