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Bustards - Species of bustards, Bustards and humans

birds habitat africa kori

Bustards are 22 species of tall birds that make up the family Otidae. Bustards occur in relatively open habitats in Africa, central and southern Europe and Asia, Southeast Asia, and Australia. Most species, however, are African.

Bustards are large birds, with species ranging in body length from 14.5-52 in (37-132 cm), and in weight from 1-48 lbs (0.6-22 kg). Bustards have a stocky body, a long neck, and stout legs and feet, with three toes pointing forward, and no hind toe. The wings are broad, and the tail is short. The bill is stout, flattened, and blunt.

Bustards are colored in various subdued hues and patterns of brown, buff, gray, black, and white. Bustards are sexually dimorphic, with males being larger and more brightly colored than females.

Some species of bustards occur during the nonbreeding season in flocks of various size. Bustards walk while feeding, and although they can fly, they tend to run to escape from predators. Bustards have keen vision, and are wary and difficult to approach closely on foot. Bustards are omnivores, eating a wide range of plant and animal foods. Bustards predate on large insects such as grasshoppers and beetles, as well as on small reptiles and nestling birds.

Bustards nest on the ground, and lay one to five eggs. The female incubates the eggs and cares for the young birds, which are precocious and can leave their nest soon after hatching.


The great bustard (Otis tarda) occurs in scattered populations in Eurasia. Its present distribution is greatly reduced compared with several centuries ago because of overhunting and conversions of its natural habitat to agriculture. However, this species is still abundant in some places where its seasonal flocks can contain as many as 500 birds. The male great bustard has a spectacular courtship display in which internal air sacs are expanded to greatly puff out the chest while white plumes are erected on the wings, tail, breast, and head. This strutting display is generally performed on slightly raised ground, in front of a hopefully appreciative audience of as many as six female birds.

The little bustard (Otis tetrax) is another Eurasian species with a similarly wide distribution as the great bustard. This and the preceding species undertake seasonal A Kori bustard (Ardeotis kori) in courtship display. Photograph by Nigel J. Dennis. Photo Researchers, Inc. Reproduced by permission. migrations, flying south from the northern parts of their range. The Houbara or MacQueen's bustard (Chlamydotis undulata) occurs from the Canary Islands off western Africa, through North Africa, as far as southwestern Asia.

The Australian bustard (Ardeotis australis) is the only species to occur on that continent. This species utilizes rather dense, shrubby habitat, in contrast to the open spaces preferred by other species of bustards.

The smallest bustards are the lesser florican (Sypheotides indica) and the Bengal florican (Houbaropsis bengalensis) of India. The world's heaviest flying bird is the great bustard, which can achieve a weight of 48 lb (22 kg). Other large species include those in the genus Ardeotis, such as the Kori bustard (A. kori) of Southern Africa.


Bustards are large, palatable birds, and they are hunted for sport or as food in most parts of their range. Some species of bustards have become endangered through the combined effects of overhunting and conversions of their habitat to agricultural land uses. Other species, while not endangered, have had their breeding ranges significantly reduced. The great bustard, for example, was extirpated in England in 1832.


Resources

Books

Bird Families of the World. Oxford: Oxford University Press, 1998.

Brooke, M., and T. Birkhead. The Cambridge Encyclopedia of Ornithology. Cambridge, UK: Cambridge University Press, 1991.

Johnsgard, P.A. Bustards, Hemipodes, and Sandgrouse. Oxford: Oxford University Press, 1991.


Bill Freedman

KEY TERMS

. . . . . . . . . . . .

Conversion

—In the ecological context, this usually refers to a managed change of a natural ecosystem to one dominated by a human purpose, such as agriculture or an urbanized land-use. Losses of habitat associated with these sorts of conversion are among the most important causes of extinction and endangerment.

Dimorphic

—This refers to the occurrence of two different shapes or color forms within the species, usually occurring as sexual dimorphism between the males and females.

Extirpated

—The condition in which a species is eliminated from a specific geographic area of its habitat.

Over-hunting

—Harvesting of wild animals at a rate that exceeds their capacity for regeneration, causing their population to collapse.

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about 5 years ago

Very useful, thank you (: