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For other uses, see Gyrfalcon (disambiguation).
Gyrfalcon or gerfalcon
Falco rusticolus white cropped.jpg
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Falconiformes
Family: Falconidae
Genus: Falco
Subgenus: Hierofalco
Species: F. rusticolus
Binomial name
Falco rusticolus
Linnaeus, 1758

The gyrfalcon (Falco rusticolus) (/ˈɜrfɔːlkən/ or /ˈɜrfælkən/), also spelled gerfalcon, is the largest of the falcon species. 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. The gyrfalcon is dispersed throughout much of the Northern Hemisphere, with populations in Northern America, Greenland, and Northern Europe. Its plumage varies with location, with birds being coloured from all-white to dark brown. For centuries, gyrfalcon has been a precious hunting bird, highly valued among the Vikings. It is the national symbol of Iceland.

The bird's common name comes from French gerfaucon; in medieval Latin it is gyrofalco. The first part of the word may come from Old High German gîr (cf. modern German Geier) for "vulture", referring to its size compared to other falcons; or from the Latin gȳrus for "circle" or "curved path"—from the species' circling as it searches for prey, distinct from the hunting of other falcons in its range.[nb 1] The male gyrfalcon is called a gyrkin in falconry. The scientific name is composed of the Latin term for a falcon, Falco, and for a countryside-dweller, rusticolus.


The gyrfalcon is a very large falcon, being about the same size as the largest buteos (buzzard hawks). Males are 48 to 61 cm (19 to 24 in) long, weigh 805 to 1350 g (1.8 to 3 lbs) and have a wingspan from 110 to 130 cm (43 to 51 in). Females are bulkier and larger, at 51 to 65 cm (20 to 26 in) long, 124 to 160 cm (49 to 64 in) wingspan, and of 1180 to 2100 g (2.6 to 4.6 lbs) weight. Among standard measurements, the wing chord is 34.5 to 41 cm (13.6 to 16.1 in), the tail is 19.5 to 29 cm (7.7 to 11.4 in), the culmen is 2 to 2.8 cm (0.79 to 1.10 in) and the tarsus is 4.9 to 7.5 cm (1.9 to 3.0 in).[2] The gyrfalcon is larger than the peregrine falcon, which it is known to hunt, and differs from the buzzard in general structure, being unmistakably a falcon with pointed wings, and broader-winged and longer-tailed than the Peregrine.

The gyrfalcon is a very polymorphic species, so its plumage varies greatly. The archetypal morphs are called "white", "silver", "brown", and "black", though they can be coloured on a spectrum that begins with all-white and ends with very dark. The brown form of the gyrfalcon is distinguished from the Peregrine by the cream streaking on the nape and crown and by the absence of a well-defined malar stripe and cap. The black morph has its underside strongly spotted black, rather than finely barred as in the Peregrine. White form gyrfalcons are unmistakable, as they are the only predominantly white falcons. Silver gyrfalcons resemble a light grey lanner falcon of larger size. There is no difference in colouring between males and females; and juveniles are darker and browner than the corresponding adults.


Systematics and evolution[edit]

A hybrid white gyrfalcon × saker



Adult F. r. islandus at Dimmuborgir near Lake Myvatn (Iceland)




Swarth's gyrfalcon was on the upper end of the present gyrfalcon's size range, strong females even surpassing it.[14] It seems to have had some adaptations to the temperate semiarid climate that predominated in its range during the last ice age. Ecologically more similar to the Siberian populations of today (which are generally composed of smaller birds) or to the prairie falcon, this population of temperate steppe habitat must have preyed on landbirds and mammals rather than the water—and on the seabirds which make up much of the American gyrfalcon's diet today.


The gyrfalcon was originally thought to be a bird of tundra and mountains only; however, in June 2011 it was revealed that it spends considerable periods during the winter on sea ice far from land.[17] It feeds only on birds and mammals, the latter of which it takes more regularly than many other Falco species. Like other hierofalcons, it usually hunts in a horizontal pursuit, rather than with the peregrine's speedy stoop from a height. Most prey is killed on the ground, whether they are captured there or, if the victim is a flying bird, forced to the ground. The diet is to some extent opportunistic, but a majority of breeding birds mostly rely on Lagopus grouse and avian marine species on coastal habitats. Avian prey can range in size from redpolls to geese and can include gulls, corvids, smaller passerines, waders, and other raptors (up to the size of Buteos). Mammalian prey can range in size from shrews to marmots (sometimes thrice the weight of the assaulting falcon), and often includes lemmings, voles, ground squirrels, and hares. They are rarely observed eating carrion.



The only natural predator of gyrfalcons are golden eagles and even they rarely engage with these formidable falcons. Gyrfalcons have been recorded as aggressively harassing animals that come near their nests, although common ravens are the only predators known to successfully pick off Gyrfalcon eggs and hatchlings. Even brown bears have been reportedly dive-bombed. Humans, whether accidentally (automobile collisions or poisoning of carrion to kill mammalian scavengers) or intentionally (through hunting), are the leading cause of death for gyrfalcons. Gyrfalcons that survive into adulthood can live up to 20 years of age.


Interaction with humans[edit]

Tame gerfalcon striking grey heron (1920), Louis Agassiz Fuertes.

The gyrfalcon has long associated with humans, who have found them useful primarily for hunting and the art of falconry. It is today the official bird of Canada's Northwest Territories. The white falcon in the crest of the Icelandic Republic's coat of arms is a variety of Gyrfalcon. The white phase gyrfalcon is the official mascot of the United States Air Force Academy.[18]

In the medieval era, the gyrfalcon was considered a royal bird. The geographer and historian Ibn Said al-Maghribi (d. 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).[19] 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.[20]


Most historians agree that Coat of Arms of Ukraine, the medieval symbol, was not intended as depicting a trident, but most likely a stylized falcon. Depictions of a flying falcon with a cross above its head have been found in Old Ladoga, the first seat of Kievan Rurik dynasty,[22] of Scandinavian lineage.[23] Such a falcon, along with a cross are also featured on the coins of Olaf Guthfrithsson, Viking konung.[22] Falconry for centuries has been a royal sport in Europe. The gyrfalcon (known also as the Norwegian falcon) was considered a royal bird and is mentioned (ukr.: кречет) in one of the earliest epics of Ruthenia, the 12th century poem The Tale of Igor's Campaign.




  1. ^ In Scandinavian languages, it is generally named after its use in falconry, whereas the modern Dutch name giervalk is peculiarly ambiguous: Gier means "vulture", whereas gieren means changing the yaw angle to circle in the air.


  2. ^ Gyrfalcon — Birds of North America Online. (2008-10-27). Retrieved on 2013-03-09.
  3. ^ Black Gyrs. Retrieved on 2011-12-18.
  5. ^ Wink, Michael; Seibold, I.; Lotfikhah, F. & Bednarek, W. (1998) Molecular systematics of holarctic raptors (Order Falconiformes). In: Chancellor, R.D., Meyburg, B.-U. & Ferrero, J.J. (eds.): Holarctic Birds of Prey: 29–48. Adenex & WWGBP.
  6. ^ Wink, Michael; Sauer-Gürth, Hedi; Ellis, David & Kenward, Robert (2004) Phylogenetic relationships in the Hierofalco complex (Saker-, Gyr-, Lanner-, Laggar Falcon). In: Chancellor, R.D. & Meyburg, B.-U. (eds.): Raptors Worldwide: 499–504. WWGBP, Berlin.
  7. ^ Nittinger, F.; Haring, E.; Pinsker, W.; Wink, Michael & Gamauf, A. (2005). "Out of Africa? Phylogenetic relationships between Falco biarmicus and other hierofalcons (Aves Falconidae)". Journal of Zoological Systematics and Evolutionary Research 43 (4): 321–331. doi:10.1111/j.1439-0469.2005.00326.x. 
  8. ^ Johnson, Jeff A.; Ambers, Angie D.; Burnham, Kurt K. (2012). "Genetics of plumage color in the Gyrfalcon (Falco rusticolus): analysis of the melanocortin-1 receptor gene". Journal of Heredity 103 (3): 315–321. doi:10.1093/jhered/ess023. PMID 22504110. 
  9. ^ a b Snow, David W.; Perrins, Christopher M.; Doherty, Paul & Cramp, Stanley (1998): The complete birds of the western Palaearctic on CD-ROM. Oxford University Press. ISBN 0-19-268579-1
  11. ^ White, Clayton M. (1994): 58. Gyrfalcon. In: del Hoyo, Josep; Elliott, Andrew & Sargatal, Jordi (editors): Handbook of the Birds of the World, Volume 2 (New World Vultures to Guineafowl): 274, plate 28. Lynx Edicions, Barcelona. ISBN 84-87334-15-6
  12. ^ Johnson, Jeff A.; Burnham, Kurt K. (2013). "Timing of breeding and offspring number covary with plumage colour among Gyrfalcons Falco rusticolus". Ibis 155 (1): 177–188. doi:10.1111/j.1474-919X.2012.01276.x. 
  13. ^ Miller, Loye H. (1927). "The Falcons of the McKittrick Pleistocene". Condor 29 (3): 150–152. doi:10.2307/1363081. 
  14. ^ a b Miller, Loye H. (1935). "A Second Avifauna from the McKittrick Pleistocene". Condor 37 (2): 72–79. doi:10.2307/1363879. 
  15. ^ Howard, Hildegarde (1971). "Quaternary Avian Remains from Dark Canyon Cave, New Mexico". Condor 73 (2): 237–240. doi:10.2307/1365844. 
  16. ^ Emslie, Steven D. (1985). "The late Pleistocene (Rancholabrean) avifauna of Little Box Elder Cave, Wyoming". Rocky Mountain Geology 23 (2): 63–82. 
  17. ^ Burnham, Kurt K.; Newton, Ian (2011). "Seasonal movements of Gyrfalcons Falco rusticolus include extensive periods at sea". Ibis 153 (3): 468. doi:10.1111/j.1474-919X.2011.01141.x. 
  18. ^ [1]. Gyrfalcon. Retrieved 2014-10-01.
  19. ^ Ibn Said al-Maghribi: Geographia (Arabic). Retrieved on 2011-12-18.
  20. ^ Berners, Juliana (1486) The Boke of St. Albans. St. Albans Press, London.
  21. ^ Beijing Municipal Administration of Cultural Heritage (2006) Contest for the Southern Capital between the Liao, Song and Jin Dynasties. Version of 2006-07-19. Retrieved 2007-08-13.
  22. ^ a b Coat of arms of Rurik found in Ladoga. (Russian)
  23. ^ Rurik (Norse leader) Britannica Online Encyclopedia
  24. ^ Gyr Genetics. Retrieved on 2011-12-18.
  25. ^ Lierz, Michael; Hafez M. Hafez, Robert Klopfleisch, Dörte Lüschow, Christine Prusas, Jens P. Teifke, Miriam Rudolf, Christian Grund, Donata Kalthoff, Thomas Mettenleiter, Martin Beer, and Timm Harder (November 2007). "Protection and Virus Shedding of Falcons Vaccinated against Highly Pathogenic Avian Influenza A Virus (H5N1)". Emerging Infectious Diseases (Centers for Disease Control) 13 (11): 1667–74. doi:10.3201/eid1311.070705. PMC 3375792. PMID 18217549. 

External links[edit]

Historical material[edit]

  • "Gyrfalcon", Thomas Nuttall, A manual of the ornithology of the United States and of Canada; volume 1, The Land Birds (1832).