The Peregrine Falcon ( Falco peregrinus ) is a cosmopolitan bird of prey in the family Falconidae . It can also be known just as the Peregrine , and was once called the `` Duck Hawk '' in North America . The Peregrine Falcon ( Falco peregrinus ) , also known as the Peregrine , and historically as the `` Duck Hawk '' in North America , is a cosmopolitan bird of prey in the family Falconidae .