Scrub jay
From Free net encyclopedia
{{Taxobox
| color = pink
| name = Scrub jays
| image = Floridascrubjay92lg.web.jpg
| image_width = 275px
| image_caption = Florida Scrub Jay
| regnum = Animalia
| phylum = Chordata
| classis = Aves
| ordo = Passeriformes
| familia = Corvidae
| genus = Aphelocoma
| genus_authority = Cabanis, 1851
| subdivision_ranks = Species
| subdivision =
Aphelocoma californica
Aphelocoma coerulescens
Aphelocoma insularis
Aphelocoma ultramarina
Aphelocoma unicolor
}}
The scrub jays are passerine birds of the genus Aphelocoma. They are New World jays found in Mexico, western Central America and the western United States, with an outlying population in Florida. Like all jays, they are closely allied to the magpies and treepies. The names 'jay', 'treepie' and 'magpie' are to a certain extent interchangeable, not reflecting any genuine genetic difference between the groups.
Contents |
Species
Five species of scrub jay are now recognised, since two taxa formerly treated as races of A. coerulescens were recently split off as separate species (A. californica, A. insularis). The species differ in colour and bill size. They live in open pine-oak forests and chaparral scrub habitats.
- Western Scrub Jay A. californica – western United States from Oregon to west Texas and south to Baja California and central Mexico
- Florida Scrub Jay A. coerulescens – Florida
- Island Scrub Jay A. insularis – Santa Cruz Island off southern California
- Mexican Jay or Gray-breasted Jay Aphelocoma ultramarina – Sierra Madre Oriental and Sierra Madre Occidental mountains of Mexico, north to southeast Arizona, southwest New Mexico and westernmost Texas, US.
- Unicolored Jay Aphelocoma unicolor – southern Mexico east to Honduras
Appearance
The scrub jays are slightly larger than the Blue Jay, and differ in having a longer tail, slightly shorter, more rounded wings and no crest on the head. The top of the head, nape and sides of the head are a rich deep blue, in some species with a white stripe above the eye and dark ear coverts. The breast is also white or grey-white and the back is a grey-brown contrasting with the bright blue tail and wings in most species. One species, Unicolored Jay, is blue all over, similar to the Pinyon Jay from much further north. The bill, legs and feet are black.
Behavior
Food is taken both on the ground and in trees. Acorns and pine nuts are the most important foods, making up the great bulk of the diet, with grain, berries and other fruits making up the rest of the vegetable diet. Many insects and other invertebrates are also taken, and eggs and nestlings, small frogs, mice and reptiles.
Wild scrub jays are frequent visitors at campsites and picnics and have frequently learned to eat from the hands of people where they have become accustomed to being fed.
The nest is in a tree or a bush, sometimes quite low down. The nests are compact and lined with hair and fine roots with an outer diameter of about 30cm to 60cm. Usually 2 to 4 eggs are laid and incubated over 14 to 16 days. There are two main variations of egg shell color: green with olive markings or a paler background of grayish-white to green with red-brown markings. The Florida Scrub Jay and the Mexican Jay both have cooperative breeding systems involving several 'helpers' at each nest, usually siblings of the main pair.
Like all jays, the scrub jays are quite vocal and have a huge range of sounds and calls; common calls include a cheek, cheek, cheek and a guttural churring krr'r'r'r'r. Scrub jays are also, like all other jays, often times quite aggressive at feeding areas, and sometimes regarded as a nuisance.