Gyrfalcon, Falco rusticolus
Scientific: Falco rusticolus
Spanish: Halcón Gerifalte
French: Faucon gerfaut
Taxonomy and Subspecies
Forms a superspecies with the Saker Falcon, Lanner Falcon, Lagger Falcon Falco jugger and maybe the Black Falcon F. subniger. [GRIN 2010].
The “Altai-Falcon” is probably a hybrid between Gyrfalcon and Saker Falcon.
Several subspecies have been described but not considered monotypic [GRIN 2010].
Length: 50-60 cm
Wingspan: 110-128 cm
Weight: Male 960-1,300 g, Female 1,400 – 2,000g
Largest falcon in the world.
13 years in the wild, 19 years in captivity. [Mebs & Schmidt 2006]
The Gyrfalcon is a raptor of open landscapes in the artic tundra. Also found in mountain crags above tree line [GRIN 2010]. Nests are often found along rivers and at costal cliffs, often near seabird colonies [Mebs & Schmidt 2006].
Circumpolar. The Gyrfalcon is found around the Artic in Alaska, northern Canada, northern Russia, Scandinavia, Greenland and Iceland.
Adult Gyrfalcons prefer to stay in the breeding areas all year but this depends on the availability of available prey, particularly Willow Grouse and Ptarmigan. Also, birds from the high Artic move south to avoid the long hours of darkness there [Potapov & Sale 2005]. Juvenile birds move further around [Mebs & Schmidt 2006]. Sometimes they can be seen as far south as Germany but this are mostly single birds.
Gyrfalcons are also rare winter to the British Isles [Newton 2010].
Breeding and Reproduction
Gyrfalcons nests on cliffs and also in tree nests. They do not built their own nests but use nests built by other large birds like Ravens or Rough-legged Buzzards. Gyrfalcons first breed at the age of two years [Potapov & Sale 2005]. Clutch size is normally 3 or 4 eggs, but only 1 or two eggs also occurs. In rare cases, 5 eggs are laid.
Incubation time is 34-36 days. As with most raptors, the female incubates more than the male which is responsible for bringing food to the nest.
After hatching, the young stay in the nest for another 46-53 days.
After leaving the nest, the young are dependent on their parents. They develop their hunting skills only slowly and for the first 6 weeks, they rely mostly on food brought to them by their parents [Potapov & Sale 2005].
Food and hunting
In many areas, Ptarmigan Lagopus muta and Willow Grouse Lagopus lagopus are the most important food source, especially during the breeding season. Those species can make up more than 90% of the diet of Gyrfalcons [Mebs & Schmidt 2006, Potapov & Sale 2005].
Other birds are also taken from the size of pipits up to Black-throated Divers and Capercaillie. Falcons at the coast also take more seabirds like Kittiwakes. Waders and Ducks are also taken.
Mammals are less important than birds but voles and especially lemmings can be an important food source when abundant.
During winter, Gyrfalcons also take carrion, for example Reindeer [Potapov & Sale 2005].
The Gyrfalcon is a very skilled hunter. The large falcon is capable of killing it’s prey both on the ground and in flight.
Population in Europa (without Greenland) about between 805 and 1,251 pairs [Mebs & Schmidt 2006]. In Iceland there are between 300 – 400 pairs, in Norway 300 – 481. Schweden has about 80 – 135 pairs, Finnland 25 – 35 and Russia 100 – 200 pairs [Mebs & Schmidt 2006].
Population in Greenland 500 – 1,000 pairs [BirdLife International 2004].
Gyrfalcons are threatened by illegal shooting, capture and stealing of eggs and young. Disturbance can also have a negative effect. The hunting of grouse can negatively affect the available prey for the falcons, especially during winter [Mebs & Schmidt 2006]. In the long term, Climate Change may have a negative effect on the Gyrfalcon, for example when forests move further north.
Illegal shooting, egg collection and taking of young, for example for falconry must be stopped and should be better controlled and persecuted. Of course this is not always easy in the remote breeding areas of the species. Better education might also be helpful.
Hunting of grouse should be reduced so that Gyrfalcons are not negatively affected.
Climate Change must be reduced to minimum.
The installation of artifical nests can be helpful [Mebs & Schmidt 2006].
Least Concern (LC)
Status Global Raptor Information Network
[BirdLife International 2004] BirdLife International. 2004. Birds in Europe: population estimates, trends and conservation status. BirdLife Interntional. Cambridge, UK. (Gyrfalcon species account available at: http://www.birdlife.org/datazone/species/BirdsInEuropeII/BiE2004Sp3620.pdf)[GRIN 2010] Global Raptor Information Network. 2010. Species account: Gyrfalcon Falco rusticolus. Downloaded from http://www.globalraptors.org on 13 Aug. 2010
[Mebs & Schmidt 2006] Mebs, Theodor & Schmidt, Daniel (2006). Die Greifvögel Europas, Nordafrikas und Vorderasiens. Kosmos Verlag.
[Newton 2010] Newton, Ian (2010). Bird Migration. The New Naturalist Library. Collins.
[Potapov & Sale 2005] Potapov Eugene, Sale Richard, (2005). The Gyrfalcon. Poyser
Forsman, Dick (1999). The Raptors of Europe and the Middle East A Handbook of Field Identification. PoyserMebs, Theodor & Schmidt, Daniel (2006). Die Greifvögel Europas, Nordafrikas und Vorderasiens. Kosmos Verlag.
Potapov Eugene, Sale Richard, (2005). The Gyrfalcon. Poyser