Falcon Identification: The 6 North American Falcons

A falcon is identified first by shape. The Hawk Migration Association of North America (HMANA) guide gives the three silhouettes side by side:

• Falcons: streamlined, with long pointed wings, a long tapered tail and strong rowing wingbeats. HMANA adds that the wings look less pointed and the tail less tapered when the bird is not in direct flight, for example while soaring.
• Accipiters (Cooper's and Sharp-shinned Hawks): short, wide, rounded wings, a long tail and a flap-flap-flap-glide flight.
• Buteos (Red-tailed and relatives): broad wings and a broad rounded tail, often soaring in wide circles high up.

Audubon uses the same test to separate the Merlin from the similar-sized Sharp-shinned Hawk: pointed wingtips on the falcon, rounded on the hawk. Bird Collective adds a behavioral clue: falcons are open-country hunters built for speed, not perch-and-wait or forest hunters. For hawk shapes in detail, see hawk identification in flight.

• [American Kestrel](/lookup/ducks-and-raptors/american-kestrel): the smallest and most common (Bird Collective). HMANA gives 8-11 in, jay-sized, pale below with buoyant flight; the male has a rufous tail and blue wings, the female a reddish tail barred with brown and brown-barred wings. It perches on fences and poles.
• [Merlin](/lookup/ducks-and-raptors/merlin): 10-14 in (Audubon), relatively short-tailed, dark and heavily streaked below with a banded tail and fast direct flight (HMANA). Audubon describes three forms: the widespread Taiga form, the pale Prairie form, whose females look like small Prairie Falcons, and a scarce blackish Pacific form on the Northwest coast.
• [Peregrine Falcon](/lookup/ducks-and-raptors/peregrine-falcon): 14-19 in, wingspan 2 ft 7 in to 3 ft 9 in, with a dark hooded head (Audubon). HMANA describes a light breast and throat, crow size and quick, powerful wingbeats. Young birds are browner and streaked below.
• Prairie Falcon: 14-19 in, wingspan 2 ft 11 in to 3 ft 7 in; brown, paler than a Peregrine, with a narrow dark whisker mark and a heavy black mark under the base of the wing (Audubon). Western, in open hills, plains and deserts.
• Gyrfalcon: the largest falcon in the world. Females are 22.8 in to 2 ft 1 in with a wingspan up to 4 ft 11 in. Most North American birds are gray, with dark and white morphs; Audubon says only a few come as far south as the Canadian border in winter.
• Aplomado Falcon: smaller than a Peregrine, with a bold black-and-white face pattern and a reddish belly; in the United States it occurs in South Texas (Bird Collective).

• Prairie Falcon: the same size. Audubon separates it by the lack of a dark hooded look, the paler plumage, especially on the tail and underparts, and the black 'armpits'; HMANA calls them dark armpits and partial wing linings.
• Gyrfalcon: larger and broader-winged. Audubon says all but the darkest Gyrfalcons lack the Peregrine's hooded effect, and none has the Prairie Falcon's black wingpits.
• Female Prairie-form Merlin: pale enough to be confused with a Prairie Falcon, Audubon notes, but much smaller.

In flight, the underwing is the quickest check: a dark patch where the wing meets the body means Prairie Falcon.

HMANA's lengths put the falcons in order, and the places each one turns up follow from Audubon and Bird Collective:

• American Kestrel, 8-11 in: fences and poles; Bird Collective calls it common throughout America.
• Merlin, 9-12 in: hunts small birds such as House Sparrows and Horned Larks, taking them in the air from a perch (Audubon). The International Hummingbird Society lists it among the birds that take hummingbirds.
• Peregrine Falcon, 14-18 in: found on every continent except Antarctica (Bird Collective); in cities, Audubon says, it nests on building ledges and feeds on pigeons.
• Prairie Falcon, 14-18 in: open country in the West; Audubon notes it increasingly winters in southwestern cities.
• Gyrfalcon, 19-24 in: Arctic tundra and coasts; a rare winter visitor to the northern states.

Audubon's own measurements run a little larger for some species (Merlin 10-14 in, Peregrine and Prairie 14-19 in), and females are larger than males in several of them, so use the ladder to compare birds, not to measure one.

The Peregrine's hunting dive, the stoop, is the famous part. Audubon says it hunts by flying very high and diving to strike prey out of the air, reaching well over 100 mph; Bird Collective cites more than 240 mph for the stoop. Either way, a falcon folding its wings and dropping on pigeons is almost certainly a Peregrine.

Audubon's population estimates: Peregrine Falcon about 340,000, stable or increasing after its collapse from DDT between the 1940s and 1970s and later reintroductions; Prairie Falcon about 110,000 and stable.

Research and drafting for this page were assisted by AI and checked line by line against the sources listed below. If you find an error, tell us and we will correct it.