A Peregrine is built for speed and power. Its head is smaller than its hawk relatives, and hard, compacted plumage covers its body. Its long, pointed wings and broad, streamlined body enable it to fly so fast that it has been called the cheetah of the sky. When a Peregrine falcon dives, it becomes the fastest animal in the world, a feathered bullet aimed at its prey. The Peregrine's stunning speed is a performance in two acts. First, it pumps its wings until it is flying about 50 miles per hour. Then, folding its wings tightly against its body, it drops into a dive that falconers call a "stoop." When its plunge is enhanced by the pull of gravity, the Peregrine reaches a speed of more than 200 miles per hour.

A Peregrine Falcon prefers to catch its prey on the wing, usually killing a bird by slamming it with its fisted talons. If the bird is merely stunned, the falcon swoops down to grab it. Falcons use their notched beak to sever the spine of their prey at the neck. Peregrines, though only about the size of a crow, can kill larger birds, such as pigeons and ducks. There have even been reports of Peregrines killing birds as large as a Great Blue Heron. When prey birds are scarce Peregrines may hunt rabbits and other small ground-dwelling rodents. Though uncommon, stranger prey like frogs have also been recorded.