PSITTACIFORM

Sulfur-crested cockatoo (Cacatua galerita) Rainbow lorikeet (Trichoglossus haematodus) Budgerigar (Melopsittacus undulatus) Lovebirds (Agapornis personata) (order Psittaciformes), any member of the group of more than 300 species of generally brightly coloured, noisy, tropical birds, to which the general name parrot may be applied. Various species are known as keas, cockatoos (see photograph), cockatiels, lories, lorikeets (see photograph), parrotlets (or parrolets), parakeets, budgerigars (see photograph), rosellas, conures, lovebirds (see photograph), amazons, and macaws. Although the first accurate written reference to a parrot is frequently credited to the Greek historian Ctesias, of the 5th century BC, who described clearly what is now called the blossom-headed parakeet (Psittacula cyanocephala) of India, there is no doubt that parrots were associated with man much earlier, for aborigines on all continents had parrots as pets when first visited by explorers. Parrots of many kinds have been long transported to Europe for zoos and private collections. Affluent citizens of early Rome often kept parrots in their homes and even esteemed them as delicacies of the dinner table. Scarlet macaw (Ara macao). (order Psittaciformes), group of birds consisting of a single family, Psittacidae, that includes lories, lovebirds, macaws, parakeets, parrots, keas, cockatoos, cockatiels, lorikeets, parrotlets, budgerigars, rosellas, conures, and amazons. The geographic range of the order is quite large, with species inhabiting most of the tropical and south temperate regions of the world. Twenty-eight genera are found in South and Central America, six in Africa and Madagascar, and nine in the Orient. The Australasian region, including Australia, New Guinea, New Zealand, and many South Pacific islands, supports the most species, with a total of 44 genera. Until the early 1900s, eastern North America had a native parrot, the Carolina parakeet (Conuropsis carolinensis), but this species was exterminated by humans through overhunting. The last captive specimen died in the same year (1914) and in the same zoo (Cincinnati) where the last passenger pigeon died, but the species may have survived in the wild until 1938. Ranging in size from 8 to 100 cm (3 to 40 inches), these short-necked, plump-bodied birds are easily recognized by their large, hooked bills and zygodactylous feet (two toes pointing forward and two backward). Their strong bills can chisel open the toughest of nuts, and their thick fleshy tongues aid in manipulating foodstuffs during this process. When climbing and handling food, parrots use the powerful bill as a gripping appendage. Most parrots have pointed wings and short tails that are either rounded or squared off. Though they are quick in the air, they tire easily and generally only fly from tree to tree. The macaws (Ara) can be recognized by their pointed wings and long tails. A few species, notably the cockatoos (family Cacatuinae) have crested heads. Parrots are generally brightly coloured, most often green marked with red, orange, blue, and other bright hues. Some are solid green or brown, and there are blue, gray, and bright red parrots, among others. In most species, both sexes have identical plumage. Parrots generally inhabit forested tropical areas, although some, such as the grass parakeets (Neophema) and the budgerigar (Melopsittacus undulatus), live in grasslands with scattered trees. The kea (Nestor notabilis) of New Zealand nests at high elevations but flies to the forest lowlands to feed. Psittaciforms subsist mostly on plant matter. Depending on their size, they eat grass seeds, berries, fruits, or nuts. The larger forms will also dig up roots and tubers and eat any insects that they uncover in the process. Some dietary specializations are found in the group; for example, the black cockatoos (Calyptorhynchus) eat wood-boring beetles that they gather by gnawing through the bark of trees. Unlike most nectar-feeding birds, which suck up the juices through tubular tongues, brush-tongued parrots lick the nectar from crushed flowers. The kea is more omnivorous than most parrots. It has earned the enmity of sheep farmers from its passion for sheep fat. Although it rarely attacks healthy sheep, it will kill injured sheep to obtain their fat. Most species of parrots are gregarious and some highly so; nomadic grassland species may move in groups of up to hundreds of thousands. The agricultural development of central Australia, especially the concomitant availability of water, has allowed the population increase of several species, including budgerigars and corellas (Cacatua sanguinea). Some parrots are solitary nesters, and other species are colonial; but all are monogamous. Behaviour during courtship and for pair-bond maintenance includes mutual preening, mutual feeding, vocalizations, and bill caressing. Nesting in tree hollows, sometimes lined with leaves or bark, is the norm for the order, but various exceptions occur. The orange-fronted parakeet (Aratinga canicularis) makes a hollow in a termite mound, while the kea and the flightless owl parrot (Strigops habroptilus) are examples of parrot species that nest in rock crevices. The ground parrot (Pezoporus wallicus) simply deposits its eggs in a slight depression in the ground. The white, spherical eggs laid by psittaciformes hatch after 16 to 30 days of incubation, those of the larger species requiring the most time. Small parrots may lay up to nine eggs and breed two or three times a year, but the larger species usually lay two eggs once during the year. The helpless and nearly naked young remain in the nest for some time, and both parents feed them by regurgitation. Parrots have been associated with humans throughout history. The first written reference to a parrot is credited to Ctesius, a Greek historian of the 5th century BC. Over the centuries, parrots have been popular both for public zoos and private collections. The larger parrots are quite long-lived, and life spans of more than 50 years have been verified. In the wild, most parrots are given to loud, screeching vocalizations, although some of the smaller ones also emit rather pleasant, twittering sounds. But the most renowned feature of these birds is their ability as mimics. Certain species, especially the African gray parrot (Psittacus erithacus) and some amazon parrots (Amazona), may develop extensive vocabularies, although there is no evidence that they understand themselves. The smaller forms, such as budgerigars and lovebirds (Agapornis), are less-talented mimics. Budgerigars (also called budgies, or shell parakeets) are popular household pets. Additional reading Popular works on parrots and related birds include Rosemary Low, The Complete Book of Parrots (1989); Joseph M. Forshaw, Parrots of the World (1973), and Australian Parrots, 2nd rev. ed. (1981); and William R. Eastman, Jr., and Alexander C. Hunt, The Parrots of Australia (1966), all lavishly illustrated books. Henry J. Bates and Robert L. Busenbark, Parrots and Related Birds, 3rd ed. edited and expanded by Matthew M. Vriends (1978); and the Duke of Bedford (H.W.S. Russell, 12th Duke of Bedford), Parrots and Parrot-like Birds (1954), treat all the parrots, with particular reference to aviculture. Herbert S. Zim, Parrakeets (1953), is devoted to the aviculture of the budgerigar. William C. Dilger, The Behavior of Lovebirds, Scientific American, 206(1):8898 (January 1962), is an excellent summary of the author's research into the behaviour and evolution of Agapornis. Among the more technical works are Hans von Boetticher, Papageien (1959), containing a short introduction followed by a new classification based on external morphology, especially of the cere, with all species described briefly; and Anton Reichenow, Vogelbilder aus fernen ZonenPapageien, 2nd ed. rev. and expanded by Hans von Boetticher and Joachim Steinbacher (1955), including colour paintings and brief descriptions of almost all parrots. Glen E. Woolfenden The Editors of the Encyclopdia Britannica