Cockatiel - biology.

Cockatiel - biology. Cockatiel, common name for a small, crested parrot native to Australia that is a popular pet. It is also known as a quarrion, weero, cockatoo parrot, or crested parrot. Cockatiels are gentle and affectionate birds that make good companions, especially when kept as solitary pets. Their soft call consists of a long, rolling kweel-kweel, but they can be taught to whistle basic melodies or speak simple words. Cockatiels in the wild live throughout Australia, but they are found mainly in the interior regions. They prefer open fields with groups of trees or bushes and a nearby water source. Australia bans the commercial export of this bird species. Cockatiels purchased as pets in other countries are the offspring of captive birds. From beak to tip of tail an adult cockatiel is a small bird, ranging in length from 29 to 34 cm (11 to 13 in) and weighing 75 to 125 g (3 to 4 oz). Male cockatiels (cocks) are larger than females (hens). In the wild, cockatiels display mostly slate-gray coloring. Cocks have a bright, lemon-yellow face and throat with prominent orange cheek patches and dark brown to black eyes. The pointed crest of cocks is predominantly yellow, with a grayish-yellow tint at the tip. Their white shoulder and wing patches contrast with a gray body; the beak and feet are also gray. The underside of the tail is black. Hens display similar but more subdued coloring, but the back and rump are a light gray with narrow white stripes. The underside of the tail is also striped with yellow and white markings. Genetic mutations and selective breeding have produced eight color varieties in captive cockatiels, described as pied, pearl, cinnamon, fallow, silver, lutino, whiteface, and albino. The pied cockatiel may be predominantly white or gray, with an irregular pattern of yellow, white, or gray feathers. The pearl cockatiel is primarily yellow with a checkered or scalloped pattern on the back and wings created by feathers with a yellow or white center and darker edges. Cinnamon and fallow cockatiels are both brown in color, with fallow a lighter brown than cinnamon. The silver cockatiel has metallic gray coloring and red eyes. The lutino cockatiel is mostly white or yellow, with dark red eyes, while the whiteface cockatiel is mostly gray and white with no yellow or orange. Albinos result from the combination of whiteface and lutino coloring. Combinations of these eight color variations are also common. In the wild, cockatiels band together in flocks of 12 to 100, but they may also occasionally travel in pairs. They are nomadic or migratory birds that follow the availability of food and water. Their diet consists of grains, fruits and berries, seedling grasses, and seeds. Cockatiels forage on the ground but are quick to fly up into trees to avoid birds of prey, their most common predators. Because large cockatiel flocks may devour fields of crops, some farmers consider cockatiels as pests. In northern Australia, the cockatiel mating season occurs from April to June; in southern Australia, cockatiels breed from August to December. During courtship, the cock displays his white shoulder patches to the hen, and he may drum his feet on the ground or a tree branch. If the hen flies away, the cock follows and repeats his display. Nests are built in hollow trees, usually eucalyptus trees, near fresh water. Both cock and hen take turns incubating the four to seven eggs, which hatch in about three weeks. Cockatiels are one of the few species of parrots in which both sexes share brooding responsibilities. Cockatiels do not display adult coloring until after their first molting (seasonal shedding of feathers) at six to nine months. They reach sexual maturity between 6 and 12 months. Cockatiels have an average life span of 12 to 15 years. Scientific classification: Cockatiels belong to the family Cacatuidae of the order Psittaciformes and are classified as Nymphicus hollandicus. Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.