Outarde d'Australie

Identification

The only Australian species of Ardeotis, a genus occurring in the African, Indian and Australasian regions, this bustard is a large terrestrial bird that resembles an American turkey in its form and behaviour. It is readily distinguished by its large size, long legs and habits while slowly striding across open plains. The general coloration of A. australis is black at the crown and nape, the long neck is pale grey at the front, and brown plumage cover the wings and upper body. The sexes are similar in appearance, females are smaller in stature, wingspan and weight than the males.The abdomen is white and separated from the light grey of the neck by a black band of feathers. The wing coverts are patchily coloured with black and white patterning, which is visible while at rest or especially in flight. The iris is white, and their beak is variously whitish to brown in colour.The legs are long and yellow to cream coloured.<p>Males are up to 1.2 m (47 in) tall with a 2.3 m (7.5 ft) wingspan. The average weight for males is 6.3 kg (14 lb), with a range of 4.3 to 12.76 kg (9.5 to 28.1 lb). The female is quite a bit smaller at 80 cm (31 in) tall, with a 1.8 m (5.9 ft) wingspan and an average body mass of 3.2 kg (7.1 lb) in a range of 2.4 to 6.35 kg (5.3 to 14.0 lb) but is similarly coloured.<p>The largest male recorded was 14.5 kg (32 lb), a specimen obtained in Victoria. Reports of large birds, presumably males, were given by Tom Carter in the west (16 lb), a recorded range of 16–18 lb by E. F. Boehm in South Australia was exceeded in some specimens (28 lb).The smaller specimens in records are of an unwell adult weighing 9 lb, shot by Carter at Broomehill, and a healthy but small specimen of 7½ lb captured and weighed by Dominic Serventy and Hubert Whittell at Bridgetown in 1949. Although it is the largest extant flying land bird in Australia, this long-legged bird is the smallest species in the genus Ardeotis.

Taxonomie

The species was first described by John Edward Gray in 1829, who assigned it the name Otis australis. Gray's specimen was obtained in New South Wales and was held in the General T. Davies collection. The whereabouts of that type is now unknown, after being sold to a private buyer. John Gould also provided a description in 1841, and named the bird Otis australasianus, using a skin obtained in Western Australia. That specimen was later nominated as the syntype and is held at the Academy of Natural Sciences of Philadelphia.<p>Placement within the family Otididae has been variously assigned. Gray recognised the species in the genus Otis in the first description, Gregory Mathews later proposed the names Choriotis and Austrotis, along with subspecific descriptions, and it was placed as a species of Eupodotis in the mid-twentieth century.<p>Common names for Ardeotis australis include bustard, Australian bustard, plains turkey, wild turkey and native turkey. The Arrernte name for the bird is kere artewe, and the Luritja name is kipara. The Larrakia name is danimila. The species is also presumed to be important to the Noongar peoples, whose names for the bird included the word bebilya, recorded by John Gilbert and published in Birds of Australia (Gould, 1848).

Nom scientifique

Ardeotis australis

Autorité

(Gray, JE, 1829)

Ordre

Otidiformes

Famille

Otididae

Genre

Ardeotis

Répartition et habitat

The distribution range of the species includes a wide area of the Australian continent and occasionally extends to southern parts of Papua New Guinea and Indonesia. The occurrence in the southeast of Australia has contracted and it no longer occurs in areas where it once recorded.<p>Individual range has been studied by tracking of the birds, via satellite and tagging or community derived surveys, indicating that local populations in wetter regions are more permanent and localised than the greater range of those inhabiting more arid regions.The birds may become locally abundant after land clearing or during outbreaks of grasshoppers. The greatest fidelity to a local region is reported in areas of high rainfall in the north and northwest of Australia.<p>The habitat favoured by the species is open grasslands, perhaps with some trees, spinifex plains and low shrublands. This bustard will enter denser areas of vegetation after fire, and is observed on artificial cleared areas such as golf courses and farmland.<p>The historical range in Southwest Australia included the dunes and alluvial flats of the Swan Coastal Plain, as far south as Busselton, and at the interior in what became the Wheatbelt. Vagrants were seen in other areas associated with the higher rainfall forest of the southwest region, although the species avoided forest and densely vegetated areas. Anecdotal reports from residents of the region stated that the species avoided human habitation and pastoral activities, and that over-hunting or land clearing rather than foxes were responsible for their local disappearance. The incidence of historical occurrence in southwest Australia was year round, and sometimes in large flocks.

Migration

Espèce sédentaire

Comportement

Mode de migration: Espèce sédentaire.

Conservation

Tendance de la population: en déclin.

Tendance de la population

en déclin