[order] ACCIPITRIFORMES | [family] Accipitridae | [latin] Hamirostra melanosternon | [authority] Gould, 1841 | [UK] Black-breasted Buzzard | [FR] Milan a plastron | [DE] Schwarzbrust-Milan | [ES] Milano de Pecho Negro | [NL] Buizerdwouw
Members of the genus Hamirostra are large, heavy-bodied kites. Their wings are like those of the Buteo genus, broad and moderately long. The tail is short and broad. They have a large, coarse beak, and are larger and heavier in the legs, feet and talons than are most other kites. Plumage streaked and mottled with rufous, brown and black. This genus seems to be an aberrant and, in some regards, primitive kite, despite its more or less buteo-like proportions. The genus contains only one species in Australia.
Above, crown and nape are pale rufous, broadly streaked with black. The back and scapulars have dark centres and rufous edges, paler towards the rump, giving a mottled rufous and black appearance. The tail is a dull sepia brown. Upper-wing coverts are rufous with dark central streaks. Primaries are black at the tips, then with a grey/brown wash forming a pale patch on upper side of the flight quills. The secondaries are a plain dull sepia, paler towards base of wing, with some rufous edging. Below, the whole underside from chin to tail coverts is a pale rufous, streaked on the breast with black, sometimes coalescing into a black patch. The tail below is grey. Under-wing coverts are pale rufous with black and white mottlings, the greater primary coverts white with dark grey centres. The underside of the wing primaries is dark grey/brown at the tips with a noticeable white patch at the base. The rest of wing quills are a uniform grey brown. The eyes are light brown to yellow, the cere dirty white, and the legs white to pinkish white, even yellow. In adult plumage the blackish head and back contrast with a rufous collar and rufous feathers on the shoulders and mantle. The under-surface is generally ruddy, with a black breast in strong contrast. A conspicuous round white patch at the carpal joint of the wing is distinctive in flight. It varies a great deal, however, and can in some plumages be confused with the Little Eagle (Hieraaetus morphnoides). Atypically, the males are usually less richly coloured than are the females.
Listen to the sound of Black-breasted Buzzard
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Australasia : Australia. The Black-breasted Buzzard Kite can be found only in the northern and interior parts of Australia, away from densely forested country. It is rather rare throughout this range; and is commonest in north Queensland and Northern Territory.
Native to Australia, the Black-Breasted Buzzard is found mainly in the northern and central parts of the continent, living in the deserts, dry grasslands, shrublands, sparse tropical woodlands and tree-lined watercourses. It does not occur in Tasmania.
The pair spend much time around the nesting area for about two months before egg-laying. The nest is built in trees, generally in a main fork, 20 70 feet from the ground and high up where tall trees are available. It is a large structure of sticks used year after year if the birds are undisturbed, four to five feet across and two to three feet deep, with a shallow cavity lined with plentiful green leaves, added from about one month before egg-laying.
Two eggs are laid between July and November, with September commonest. The whole breeding cycle covers from July to December in various parts of the range, and there is a tendency to earlier breeding in the north.
Only the female incubates, and usually only one young bird is reared in any nest. The incubation period is about 40 days, with chicks fledging about 60 days after hatching.
The diet consists principally of rabbits. It also eats reptiles, including snakes, and some birds, but rarely consumes carrion and does not molest sheep. All its food is taken on the ground.
Video Black-breasted Buzzard
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be small, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
The most remarkable habit attributed to it is that of dropping stones on Emus’ and Bustards’ eggs to break them and so obtain the contents. According to reports from aborigines, the Buzzard Kite is first said to advance on the sitting Emu and drive it off its nest by threat display with open wings. It then flies up and drops a stone or hard clod of earth into the nest, descending to eat the egg contents. There is some support for these statements by aborigines – there are records of the Buzzard Kites feeding on broken Emu eggs, and it is not unusual to find fragments of shells of Emus’ and Bustards’ eggs in the Buzzard Kites’ nests.
Poorly understood; apparently some resident and some migratory populations. Breeding birds sedentary in C Australia unless forced to move by drought; dry season (austral winter and spring) breeding migrant to N Australia, withdrawing from tropical coasts in wet season; avoids CW Australia in summer. Occasional minor irruptions to S and E parts of range during inland drought.