Gyrfalcon Falco rusticolus

Identification Tips:

• Length: 20 inches Wingspan: 48 inches
• Very large falcon
• Long, broad-based, pointed wings
• Short, dark, hooked beak

Adult-gray morph:

• Gray upperparts
• Underparts white with dark streaks
• Flight feathers distinctly paler than wing linings
• Thin moustache mark
• Pale supercilium
• Tail gray with thin white bands
• Immature similar to adult but plumage is browner

Adult-white morph:

• White plumage
• Black barring on back and wings
• White tail
• Immature similar to adult but plumage is variably darker

Adult-dark morph:

• Dark brown upperparts
• Underparts heavily streaked
• Flight feathers distinctly paler than wing linings
• Dark tail
• Immature similar to adult

Similar species:

The long, pointed wings and long tail mark this bird as being a falcon. It is most likely to be confused with other large falcons. The white morph Gyrfalcon is distinctive. The darker morphs of the Gyrfalcon are somewhat similar to Prairie and Peregrine Falcons. The Gyrfalcon is larger, has broader wings and tail, and pale flight feathers contrasting with darker wing linings. The Prairie Falcon has a black underwing patch while the Peregrine has evenly dark underwings. At rest, the wingtips of the Gyrfalcon do not reach as far down the tail as the other falcons.

Length and wingspan from: Robbins, C.S., Bruun, B., Zim, H.S., (1966). Birds of North America. New York: Western Publishing Company, Inc.