Steller's jay

Steller's jay
In Arizona, United States
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. While it does not have as prominent a crest as the Blue Jay (Cyanocitta cristata) it can be found west of the Rockies especially in south east British Columbia.

The 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.

It occurs in coniferous forest over much of the western half of North America from Alaska in the north to northern Nicaragua[3] completely replacing the blue jay in most of those areas. Some hybridization with the blue jay in Colorado has been reported. The Steller's jay lives in coniferous and mixed woodland, but not in completely dense forest, and requires open space. It typically lives in flocks of greater than 10 individuals. In autumn, flocks often visit oak woods when acorns are ripe.

Habitat

The Steller's jay primarily lives in coniferous forests but can be found in many forested areas. They can be found in low to moderate elevations as high as the tree line, but rarely go that high. Steller's jays are common in residential and agricultural areas with nearby forests.[4]

Diet

Steller's jays are omnivores; their diet is about two-thirds plant matter and one third animal matter. Food is gathered from both the ground and from trees. The Steller's jay's diet consists of a wide range of seeds, nuts, berries and other fruit. Many types of invertebrates, small rodents, eggs and nestlings such as those of the marbled murrelet are also eaten. There are some accounts of them eating small reptiles, both snakes and lizards.[4] 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. 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.[5] 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.[6]

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 vocal mimic. It can mimic 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.[3][4]

Name

This bird is named after the German naturalist Georg Wilhelm Steller, the first European to record them in 1741.[2][7]

Provincial bird

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

Phylogeny

Steller's jay (Cyanocitta stelleri)[8] is one of two species in the genus Cyanocitta, the other species being the blue jay (Cyanocitta cristata). The Cyanocitta genus in turn belongs to the family Corvidae, which consists of the crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs, and nutcrackers, for a total of over 120 species. The closest relatives of the Corvidae are the shrikes (Laniidae), and birds-of-paradise (Paradisaeidae).

There are 17 subspecies from Alaska to Nicaragua, 8 found north of Mexico. To name a few: C. s. macrolopha of the central and southern Rockies, C. s. stelleri (Pacific coast from Alaska to southwestern British Columbia), and the largest subspecies, C. s. carlottae, from the Queen Charlotte Islands.[3]

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". The Birds of North America Online. CORNELL LAB OF ORNITHOLOGY. 2013. Retrieved 6 June 2013.
  3. 1 2 3 "Steller's Jay Cyanocitta stelleri". National Geographic. Retrieved 6 June 2013.
  4. 1 2 3 "Steller's Jay". Seattle Audubon Society. Retrieved 6 June 2013.
  5. ↑ "STELLER'S JAY". Texas Breeding Bird Atlas. Retrieved 6 June 2013.
  6. ↑ "Steller's Jay". Audubon. Retrieved 2016-04-03.
  7. ↑ Evans, Howard Ensign, (1986). Daniel Halpern, ed. Antæus on Nature. London: Collins Harvill. p. 24.
  8. ↑ "Cyanocitta stelleri". Integrated Taxonomic Information System. Retrieved 6 June 2013.
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