Five falcon species inhabit Montana: Gyrfalcon( Falco rusticolus); Peregrine Falcon (Falco peregrinus) Prairie Falcon (Falco mexicanus); Merlin (Falco columbarius); and the American Kestrel (Falco sparverius).
The Gyrfalcon, our largest species, is only a winter resident of Montana. We have no known nesting Gyrfalcons. Gyrfalcons are about the size of a Red-tailed Hawk. The Gyrfalcon migrates down from Canada in the winter and feeds on birds and rodents.
The Peregrine Falcon may be the fastest animal in the world with diving flight speeds estimated from 100mph to 275mph. The peregrine nests primarily in the south-central and western portion of the state on cliffs over waterways. Diet consists almost entirely on birds. Dark facial mask, light breast, and lack of dark feathers in the wing pit are key field marks used to separate the Peregrine Falcon from the Prairie Falcon.
The Prairie Falcon is similar to the Peregrine Falcon in size and plumage. Prairie falcons are commonly mistaken for the Peregrine Falcon. Key field marks that distinquish this falcon from the Peregrine are the dark wing pits, narrower facial mustache, and paler brown plumage. The Prairie Falcon nests on cliffs along waterways as well as cliffs in the dryer habitats. Their diet includes both birds and rodents.
The Merlin Falcon is an uncommon inhabitant usually frequenting the open plains and forest edges. Two sub-species occur: the Prairie Merlin (Richardson’s) and Pacific Merlin (Black). This falcon is about ½ the size of the Peregrine and Prairie Falcon and can be identified by its small size and banded tail. The Merlin nests in old stick nests of other birds. Merlins feed primary on small birds, rodents, and insects.
The American Kestrel is the smallest and most common falcon found in Montana. The brightly colored falcon is commonly seen on fence posts and Telephone poles along all Montana roadways. This falcon can be identified by its small size, rusty back, and two whiskers on the side of its face.
Size difference between the largest falcon (Gyr Falcon) and the smallest falcon found in North American (American Kestrel).