Rather, a cougar moves efficiently through its territory until a slight sound or movement betrays the presence of prey. Then in slow motion, the cougar creeps as close as it can. When it gets so close that the next step might alert the prey, the cat charges. In two or three fluid, lightning-quick bounds it catches its prey, using an arsenal of teeth, claws, and strength to kill the victim. Frequently the stalk and kill are so efficient that a deer dies in the spot where it rested.
Cougars have an eclectic diet, generally eating what they encounter, when they encounter it.
When deer bunch together in the winter, cougars find and eat more deer. In summer, when deer scatter more widely, the cougar adds rabbits, birds, porcupines, squirrels, raccoons, rats, and even grasshoppers to the menu. The cougar's hunting prowess is best put into perspective by comparing body weights of predator and prey. When deer are not available, a cougar can kill an elk or moose six or seven times as large as itself. Predation is an iffy business, and every successful stalk can be preceded by several failures.