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Common Name: Gyrfalcon
Scientific Name: Falco rusticolus

Size: 20-25 inches (50-63 cm); Wingspan: 48-52 inches (120-130 cm)

Habitat: Northern Hemisphere (North America, Europe and Asia). The gyrfalcon is dispersed throughout much of the Northern Hemisphere, with populations in Northern America, Greenland, and Northern Europe. The gyrfalcon breeds on Arctic coasts and the islands of North America, Europe, and Asia. It is mainly a resident there also, but some gyrfalcons disperse more widely after the breeding season, or in winter. Individual vagrancy can take birds for long distances.

It is found in the tundra, often near rivers or coasts. During winters, it is found at lower latitudes, open country and especially near water.

Status: Least Concern. Global population: 110,000 individuals. While there is no evidence of long-term population changes in North America, commercial markets in falconry may pose a threat in Scandinavia and Russia. Falcons are known to be very susceptible to avian influenza.

Diet: Large birds including ptarmigan and waterfowl. They also eat rabbits, voles, small birds, and other mammals. They locate prey while perched or in flight and then pursue their prey in flight until overtaking them. The female Gyrfalcon regularly stores prey during the breeding season, generally within 100 meters (328 feet) of the nest. Little is known of food-caching outside the breeding season; in one case, a Gyrfalcon was seen retrieving a frozen ptarmigan and chipping off pieces of meat to eat, in mid-winter in the Aleutian Islands.

Nesting: Females are noticeably larger with males being only about 65% the size of females. The plumage of the Gyrfalcon can take three main forms, white, gray, and dark, with many intermediate plumages. White adults have almost pure white breasts and bellies. The rest of their bodies are white mottled with brown. They have dark wingtips. Gray adults have gray upperparts with subtle darker mottling, and white underparts mottled with gray. Dark adults are dark-brownish overall above and brown streaked with white below.

Monogamous pairs nest on the ground or on cliff ledges, sometimes in old nests of other birds. They do not build a nest of their own. Both adults incubate the 3-4 eggs for about 35 days, although the female incubates more than the male. The female broods the young for the first few weeks after hatching, while the male brings food. After the brooding period is over, the female also hunts. The young begin to fly at 45-50 days and become independent shortly thereafter.

Cool Facts: The Gyrfalcon is the largest true falcon in the world. Gyrfalcon is pronounced as "JER-falcon." The name probably evolved from Old Norse, but linguists do not completely agree on the specific origin of the word.

Gyrfalcons have been highly regarded by falconers throughout falconry’s history. The male gyrfalcon is called a “gyrkin” in falconry. In Viking culture, the gyrfalcon was a highly valued hunting bird and during the Middle Ages in many countries, only a king could hunt with a Gyrfalcon. The white falcon in the crest of the Icelandic Republic's coat of arms is a variety of Gyrfalcon.

There is some correlation between locality and color morph. Greenland gyrfalcons are lightest, with white plumage flecked with grey on the back and wings being most common. Other subpopulations have varying amounts of the darker morphs: the Icelandic birds tend towards pale, whereas the Eurasian populations are considerably darker and typically incorporate no white birds. Natural separation into regional subspecies is prevented by gyrfalcons' habit of flying long distances whilst exchanging alleles between subpopulations; thus, the allele distributions for the color polymorphism form clines and in darker birds of unknown origin, theoretically any allele combination might be present.

Male performs spectacular aerial displays with dives and 180° rolls. Uses four methods to pursue prey: 1) flying low and surprising prey on ground; 2) pursuing prey over long distances, forcing it low or high and exhausting it; 3) hovering and making short stoops to force prey out of cover; 4) flying straight up to strike at birds overhead. Strikes prey or drives it to the ground, rather than grasping it in the air. Dead prey typically have broken breast bone.

This 3D model is found in Songbird Remix Birds of Prey Volume I: Kestrels, Hobbies and Falcons

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