Steller's jay

Steller's jay
Steller's Jay in Flagstaff, Arizona, with white head-markings typical of eastern-variety birds (C.S. macrolopha)
Scientific classification
Kingdom:Animalia
Phylum:Chordata
Class:Aves
Order:Passeriformes
Family:Corvidae
Genus:Cyanocitta
Species: C. stelleri
Binomial name
Cyanocitta stelleri
(Gmelin, 1788)

The Steller's jay (Cyanocitta stelleri) is a jay native to western North America, closely related to the blue jay found in the rest of the continent, but with a black head and upper body. It is also known as the long-crested jay, mountain jay, and pine jay. It is the only crested jay west of the Rocky Mountains.

Western-variety Steller’s jay, with all-dark head, in Alaska Maritime National Wildlife Refuge.

Steller's jay shows a great deal of regional variation throughout its range.[2] Blackish-brown-headed birds from the north gradually become bluer-headed farther south. The Steller's jay has a more slender bill and longer legs than the blue jay and has a much more pronounced crest. It is also somewhat larger.

The head is blackish-brown with light blue streaks on the forehead. This dark coloring gives way from the shoulders and lower breast to silvery blue. The primaries and tail are a rich blue with darker barring. Birds in the eastern part of its range along the Great Divide have some white markings on the head, especially over the eyes; birds in the far west along the Pacific Coast have small, very faint, or no white or light markings at all.

Name

This bird is named after the German naturalist Georg Wilhelm Steller, the first European to record them in 1741.[2][3]

Phylogeny

Steller's jay (Cyanocitta stelleri)[4] is one of two species in the genus Cyanocitta, the other species being the blue jay(Cyanocitta cristata); because the two species sometimes interbreed naturally where their ranges overlap, their status as distinct species has been contested. There are 17 subspecies of Steller's jays ranging from Alaska to Nicaragua, with 8 found north of Mexico. At least some of the variation in the species is due to different degrees of hybridization between Steller's jays (C. stelleri) and blue jays (C. cristata). To name a few:[5]

  • C. s. macrolopha (central and southern Rockies)
  • C. s. stelleri (Pacific coast from Alaska to southwestern British Columbia)
  • C. s. carlottae, the largest subspecies (Queen Charlotte Islands).

The genus Cyanocitta is part of the family Corvidae, which consists of the crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs, and nutcrackers.

Habitat

The Steller's jay occurs in coniferous forest over much of the western half of North America from Alaska in the north to northern Nicaragua[5] completely replacing the blue jay in most of those areas. Some hybridization with the blue jay in Colorado has been reported.

Although the Steller's jay primarily lives in coniferous forests it can be found in many other forested areas. They can be found from low to moderate elevations, and on rare occasions to as high as the tree line. Steller's jays are common in residential and agricultural areas with nearby forests.[6]

Diet

Steller's jays are omnivorous and can be social with humans.

Steller's jays are omnivores; their diet is about two-thirds plant matter and one third animal matter. They gather food both from the ground and from trees. The Steller's jay's diet includes a wide range of seeds, nuts, berries and other fruit. They also eat many types of invertebrates, small rodents, eggs, and nestlings such as those of the marbled murrelet. There are some accounts of them eating small reptiles, both snakes and lizards.[6]

Acorns and conifer seeds are staples during the non-breeding season; these are often cached in the ground or in trees for later consumption. They exploit human-provided food sources, frequently scavenging picnics and camp sites, where it competes with the Grey jay.

Steller's jays will visit feeders and prefer black-oil sunflower seeds, white striped sunflower seeds, cracked corn, shelled raw peanuts, and are especially attracted to whole raw peanuts. Suet is also consumed but mostly in the winter season.

Breeding

The nest is usually in a conifer but is sometimes built in a hollow in a tree. Similar in construction to the blue jay's nest, it tends to be a bit larger (25 to 43 cm (9.8 to 16.9 in)), using a number of natural materials or scavenged trash, often mixed with mud. Between two and six eggs are laid during breeding season. The eggs are oval in shape with a somewhat glossy surface. The background colour of the egg shell tends to be pale variations of greenish-blue with brown- or olive-coloured speckles.

The clutch is usually incubated entirely by the female for about 16 days.[7] The male feeds the female during this time. Though they are known to be loud, during nesting they are quiet in order to not attract attention.[8]

Vocalizations

Like other jays, the Steller's jay has numerous and variable vocalizations. One common call is a harsh SHACK-Sheck-sheck-sheck-sheck-sheck series; another skreeka! skreeka! call sounds almost exactly like an old-fashioned pump handle; yet another is a soft, breathy hoodle hoodle whistle. Its alarm call is a harsh, nasal wah. Some calls are sex-specific: females produce a rattling sound, while males make a high-pitched gleep gleep.

The Steller's jay also is a noted mimic: It can imitate the vocalizations of many species of birds, other animals, and sounds of non-animal origin. It often will imitate the calls from birds of prey such as the red-tailed hawk, red-shouldered hawk, and osprey, causing other birds to seek cover and flee feeding areas.[5][6]

Provincial bird

The Steller's jay is the provincial bird of British Columbia.

Notes

    References

    1. ↑ BirdLife International (2012). "Cyanocitta stelleri". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
    2. 1 2 "Steller's Jay". Cornell Laboratory of Ornithology. The Birds of North America Online. Cornell University. 2013. Retrieved 6 June 2013.
    3. ↑ Evans, Howard Ensign (1986). Halpern, Daniel, ed. Antæus on Nature. London, UK: Collins Harvill. p. 24.
    4. ↑ "Cyanocitta stelleri". Integrated Taxonomic Information System. Retrieved 6 June 2013.
    5. 1 2 3 "Steller's Jay Cyanocitta stelleri". National Geographic. Retrieved 6 June 2013.
    6. 1 2 3 "Steller's Jay". Seattle Audubon Society. Retrieved 6 June 2013.
    7. ↑ "Steller's Jay". Texas Breeding Bird Atlas. Retrieved 6 June 2013.
    8. ↑ "Steller's Jay". Audubon Society. Retrieved 2016-04-03.
    • Goodwin, D. (1976). Crows of the World. Seattle, WA: University of Washington Press.
    • Greene, E.; Davison, W.; Davison, W.; Muehter, V.R. (1998). "Steller's jay - Cyanocitta stelleri". The Birds of North America. No. 343.
    • Madge, S.; Burn, H. (1994). Crows and Jays: A Guide to the Crows, Jays and Magpies of the World. Boston, MA: Houghton Mifflin.
    • "Steller's jay". Cornell Laboratory of Ornithology. Species Account. Cornell University.
    • "Steller's jay media". Internet Bird Collection.
    • Steller's jay photo gallery at VIREO (Drexel University)
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