The gyrfalcon is a bird of prey (raptor) in the family Falconidae.
The abbreviation gyr is also used.
The gyrfalcon is the largest of the falcon species.
Gyrfalcons are found in the Arctic regions of Europe, Asia, North America, Greenland and Iceland. Some Gyrfalcons migrate southward in the depths of winter, but they seldom go further south than the northern United States or central Russia.
The gyrfalcon may reach 60 cm (2 feet) in length, and females, which average 1,400 to 2,100 grams (3.1 to 4.6 pounds), weigh nearly twice as much as males.
The gyrfalcon varies in color from white with dark brown speckling to white with black speckling to dark gray with barring. The legs are fully feathered.
Gyrfalcons, like other falcons, eat mainly other birds. They prefer to hunt ground birds such as ptarmigan and grouse but also hunt seabirds and waterfowl, as well as land mammals such as ground squirrels, lemmings, voles, hares, rabbits, and marmots.
The gyrfalcon is a solitary species except during the breeding season when it will interact with its mate.
Gyrfalcons are known to form monogamous pairs. Scientists think that these pairings often last until one of the birds dies.
Gyrfalcons nest on cliffs or similar sites, usually under an overhang that helps protect the nest from the weather. Nest sites will be used year after year. From this repeated use, the ground around the nest is blanketed by white guano and it accumulates piles of uneaten prey-parts.
Near the end of April, female gyrfalcons lay a clutch of up to five eggs, which are incubated by both parents. All eggs hatch approximately 35 days after they are laid, and young falcons leave the nest to hunt and forage on their own some six to eight weeks later.
Gyrfalcons that survive into adulthood can live up to 20 years of age.
The only natural predators of gyrfalcons are golden eagles, and even they rarely engage with these formidable falcons.
The gyrfalcon was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under its current binomial name Falco rusticolus.
The genus name “Falco“ is the Late Latin term for a falcon, Falco, from falx, falcis, a sickle, referencing the claws of the bird.
The species name “rusticolus“ is from the Latin rusticolus, a countryside-dweller, from rus, ruris, “country” and colere, “to dwell”.
The bird’s common name “gyrfalcon” comes from French gerfaucon – in Medieval Latin, it is gyrofalco. The first part of the word may come from Old High German gîr for “vulture”, referring to its size compared to other falcons or from the Latin gȳrus for “circle” or “curved path,” in turn from the Ancient Greek γῦρος, gûros, meaning “circle” – from the species’ circling as it searches for prey, distinct from the hunting of other falcons in its range.
The gyrfalcon has long associated with humans, primarily for hunting and in the art of falconry.
The male gyrfalcon is called a gyrkin in falconry.
In the medieval era, the gyrfalcon was considered a royal bird.
The geographer and historian Ibn Sa’id al-Maghribi (1213–1286) described certain northern Atlantic islands west of Ireland where these falcons would be brought from, and how the Egyptian Sultan paid 1,000 dinars for each gyrfalcon (or, if it arrived dead, 500 dinars). Due to its rarity and the difficulties involved in obtaining it, in European falconry the gyrfalcon was reserved for kings and nobles; very rarely was a man of lesser rank seen with a gyrfalcon on his fist.
In the 12th century AD China, swan-hunting with gyrfalcons obtained from the Jurchen tribes became fashionable among the Khitan nobility.
Inuit occasionally hunt gyrfalcon for food and feathers, which are used in clothing and in religious rituals.
Ecologists and wildlife officials note that some birds are illegally captured and sold on the black market to falconers.
It is the official bird of Canada‘s Northwest Territories.