Snowy Owl

Snowy Owl
Snowy Owl
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Strigiformes
Family: Strigidae
Genus: Bubo
Species: B. scandiacus
Binomial name
Bubo scandiacus
(Linnaeus, 1758)

     Summer      Winter
Synonyms

Strix scandiaca Linnaeus, 1758
Nyictea Scandiaca Stephens, 1826

The Snowy Owl (Bubo scandiacus) is a large owl of the typical owl family Strigidae. The Snowy Owl was first classified in 1758 by Carolus Linnaeus, the Swedish naturalist who developed binomial nomenclature to classify and organize plants and animals. The bird is also known in North America as the Arctic Owl, Great White Owl or Harfang. Until recently, it was regarded as the sole member of a distinct genus, as Nyctea scandiaca, but mtDNA cytochrome b sequence data (Olsen et al. 2002) shows that it is very closely related to the horned owls in the genus Bubo. The Snowy Owl is the official bird of Quebec.

Contents

Description

Like the related eagle-owls, the Snowy Owl has ear-tufts; they are small and usually tucked away however

This yellow-eyed, black billed white bird is easily recognizable. It is 52–71 centimetres (20–28 in) long with a 125–150 centimetres (49–59 in) wingspan. Also, these birds can weigh anywhere from 1.6–3 kilograms (3.5–6.6 lb).[2] It is one of the largest species of owl and in North America is on average the heaviest owl species. The adult male is virtually pure white, but females and young birds have some dark scalloping; the young are heavily barred, and dark spotting may even predominate. Its thick plumage, heavily-feathered taloned feet, and coloration render the Snowy Owl well-adapted for life north of the Arctic Circle.

Snowy Owl calls are varied, but the alarm call is a barking, almost quacking krek-krek; the female also has a softer mewling pyee-pyee or prek-prek. The song is a deep repeated gawh. They may also clap their beak in response to threats or annoyances. While called clapping, it is believed this sound may actually be a clicking of the tongue, not the beak.

Ecology

Young owl on the tundra at Barrow Alaska. Snowy Owls will lose their black feathers with age, though particularly females retain some.

The Snowy Owl is typically found in the northern circumpolar region, where it makes its summer home north of latitude 60 degrees north. However, it is a particularly nomadic bird, and because population fluctuations in its prey species can force it to relocate, it has been known to breed at more southerly latitudes. During the last glacial, there was a Central Europe Bubo scandiacus gallicus, but no modern subspecies are recognized.

This species of owl nests on the ground, building a scrape on top of a mound or boulder. A site with good visibility, ready access to hunting areas, and a lack of snow is chosen. Gravel bars and abandoned eagle nests may be used. Breeding occurs in May, and depending on the amount of prey available, clutch sizes range from 5 to 14 eggs, which are laid singly, approximately every other day over the course of several days. Hatching takes place approximately five weeks after laying, and the pure white young are cared for by both parents. Both the male and the female defend the nest and their young from predators. Some individuals stay on the breeding grounds while others migrate.

Range

Snowy Owls nest in the Arctic tundra of the northermost stretches of Alaska, Canada and Eurasia. They winter south through Canada and northern Eurasia, with irruptions occurring further south in some years. Snowy Owls are attracted to open areas like coastal dunes and prairies that appear somewhat similar to tundra. They have been reported as far south as Texas, Georgia, the American Gulf states, southern Russia, northern China and even the Caribbean. Between 1967 and 1975, Snowy Owls bred on the remote island of Fetlar in the Shetland Isles north of Scotland, UK. Females summered as recently as 1993, but their status in the British Isles is now that of a rare winter visitor to Shetland, the Outer Hebrides and the Cairngorms.[3] In January 2009, a Snowy Owl appeared in Spring Hill, Tennessee, the first reported sighting in the state since 1987.[4]

Hunting and diet

A Snowy Owl eating a rat at Diergaarde Blijdorp (Rotterdam Zoo), Netherlands

This powerful bird relies primarily on lemmings and other small rodents for food during the breeding season, but at times of low prey density, or during the ptarmigan nesting period, they may switch to juvenile ptarmigan. They are opportunistic hunters and prey species may vary considerably, especially in winter. They feed on a wide variety of small mammals such as meadow voles and deer mice, but will take advantage of larger prey, frequently following traplines to find food. Some of the larger mammal prey includes hares, muskrats, marmots, squirrels, rabbits, raccoons, prairie dogs, rats, moles, and entrapped furbearers. Birds preyed upon include ptarmigan, ducks, geese, shorebirds, ring-necked pheasants, grouse, American coots, grebes, gulls, songbirds, and even other raptors, including other owl species. Snowy Owls are also known to eat fish and carrion. Most of the owls' hunting is done in the "sit and wait" style; prey may be captured on the ground, in the air or fish may be snatched off the surface of bodies of water using their sharp talons. Each bird must capture roughly 7 to 12 mice per day to meet its food requirement and can eat more than 1,600 lemmings per year.

Snowy Owls, like many other birds, swallow their small prey whole. Strong stomach juices digest the flesh, while the indigestible bones, teeth, fur, and feathers are compacted into oval pellets that the bird regurgitates 18 to 24 hours after feeding. Regurgitation often takes place at regular perches, where dozens of pellets may be found. Biologists frequently examine these pellets to determine the quantity and types of prey the birds have eaten. When large prey are eaten in small pieces, pellets will not be produced.[5]

Natural Threats

Though Snowy Owls have few predators, the adults are very watchful and are equipped to defend against any kind of threat towards them or their offspring. During the nesting season, the owls regularly defend their nests against arctic foxes, corvids and swift-flying jaegers; as well as dogs, gray wolves and other avian predators. Males defend the nest by standing guard nearby while the female incubates the eggs and broods the young. Both sexes attack approaching predators, dive-bombing them and engaging in distraction displays to draw the predator away from a nest. They also compete directly for lemmings and other prey with several predators, including rough-legged hawks, golden eagles, peregrine falcons, gyrfalcons, jaegers, glaucous gulls, short-eared owls, great horned owls, common ravens, wolves, arctic foxes, and ermine. Some species nesting near snowy owl nests, such as the snow goose, seem to benefit from the protection of snowy owls that drive competing predators out of the area.[6]

In popular culture

Further reading

  • Hough, Julian (1992). Snowy Owl plumages, Birding World, 5(3):97–98.

References

  1. ^ "Nyctea scandiaca". IUCN Red List of Threatened Species. Version 2009.1. International Union for Conservation of Nature. 2009. http://www.iucnredlist.org/apps/redlist/details/143241. Retrieved 2009-01-27.  Database entry includes a brief justification of why this species is of least concern.
  2. ^ Snowy Owl, Snowy Owl Profile, Facts, Information, Photos, Pictures, Sounds, Habitats, Reports, News - National Geographic
  3. ^ Hope of first owl chicks in years, BBC News. Accessed 18 May 2008.
  4. ^ The Tennessean, "Snowy Owl appears in Middle Tenn." Accessed January 22, 2009. There was also a sighting in Jessopville, Ontario on Highway 89 and has been seen 22 and 26 May 2009 by the same person.
  5. ^ Snowy Owl — Bubo scandiacus
  6. ^ ADW: Nyctea scandiaca: Information. Animaldiversity.ummz.umich.edu. Retrieved on 2010-10-19.
  7. ^ a b Owls in Lore and Culture. The Owl Pages (2000-06-15). Retrieved on 2010-10-19.
  8. ^ Bank of Canada 1986 Series, Birds of Canada
  9. ^ Gafûru no densetsu 3D (2010), IMDB

External links


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Look at other dictionaries:

  • Snowy owl — Snowy Snow y, a. 1. White like snow. So shows a snowy dove trooping with crows. Shak. [1913 Webster] 2. Abounding with snow; covered with snow. The snowy top of cold Olympus. Milton. [1913 Webster] 3. Fig.: Pure; unblemished; unstained; spotless …   The Collaborative International Dictionary of English

  • snowy owl — ► NOUN ▪ a large northern owl that breeds mainly in the Arctic tundra, the male being entirely white …   English terms dictionary

  • snowy owl — n. a large, white owl (Nyctea scandiaca) of northern tundras that usually feeds on small mammals, esp. lemmings …   English World dictionary

  • snowy owl — a diurnal, arctic and subarctic owl, Nyctea scandiaca, having white plumage with dark brown markings. [1775 85] * * * White or barred brown and white typical owl (Nyctea scandiaca, family Strigidae) of the Arctic tundra, sometimes found in Europe …   Universalium

  • Snowy Owl — baltoji pelėda statusas T sritis zoologija | vardynas atitikmenys: lot. Nyctea scandiaca angl. Snowy Owl vok. Schnee Eule …   Paukščių anatomijos terminai

  • snowy owl — baltosios pelėdos statusas T sritis zoologija | vardynas atitikmenys: lot. Nyctea angl. snowy owl vok. Schnee Eule, f rus. белая сова, f; полярная сова, f pranc. harfang des neiges, m ryšiai: platesnis terminas – didieji apuokai siauresnis… …   Paukščių pavadinimų žodynas

  • snowy owl — baltoji pelėda statusas T sritis zoologija | vardynas atitikmenys: lot. Nyctea scandiaca angl. snowy owl vok. Schnee Eule, f rus. белая сова, f; полярная сова, f pranc. harfang des neiges, m ryšiai: platesnis terminas – baltosios pelėdos …   Paukščių pavadinimų žodynas

  • Snowy Owl Inn and Resort — (Waterville Valley,США) Категория отеля: 4 звездочный отель Адрес: 41 Village …   Каталог отелей

  • snowy owl — snow′y owl′ n. orn a diurnal arctic and subarctic owl, Nyctea scandiaca, having white plumage with dark brown markings …   From formal English to slang

  • snowy owl — /snoʊi ˈaʊl/ (say snohee owl) noun a large owl, Nyctea scandiaca, of northern Europe, Asia, and North America …  

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