yrfalcon
This bird is native to North America and Europe and has traditionally been the most prized and sought after birds for falconry.
Plumage
The immature plumage of the Gyrfalcon ranges from gray-black to almost pure white. The further north the bird's habitat, the more likely it is to be white.
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Three different Gyrfalcons. |
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An immature Gyrfalcon pumping its wings. |
Typical quarry caught with the Gyrfalcon are large birds including grouse, pheasant, waterfowl, and ptarmigan and even rabbits or snowshoe hares. In the wild this bird most typically hunts ptarmigan with the addition of geese and ducks and even rabbits.
The Gyrfalcon's typical hunting style is to pursue, sometimes over many miles. Telemetry is almost required to fly this bird. It attacks in a style of shallow stoops and zig-zags and will pursue quarry for miles. The Saker falcon has a very similar attack style and it is thought that these two are closely related.
Trivia
The Gyrfalcon is also called the Gyr, jer-falcon, gerfalcon, Greenland falcon, and Iceland Falcon. These powerful birds are common hybrids with Peregrines, Merlins, and other falcons.
The Gyrfalcon was the most prized bird used in falconry, even today. The Icelandic Gyrfalcons were the property of the King of Denmark and Iceland. These birds were given as gifts to heads of state and used as pay or ransom. Valued for their power as much as their appearance, they are an effective hunter.
The males are called "jerkins".
Immature Gyrfalcons tend to have bluish ceres and feet while adult Gyrfalcons have yellow to orange colored skin.
Links
http://www.mbr-pwrc.usgs.gov/id/framlst/i3540id.html