Black-breasted buzzard | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Accipitriformes |
Family: | Accipitridae |
Genus: | Hamirostra Brown, 1846 |
Species: | H. melanosternon |
Binomial name | |
Hamirostra melanosternon (Gould, 1841) | |
Synonyms | |
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The black-breasted buzzard (Hamirostra melanosternon) is a large raptor endemic to mainland Australia. First described by John Gould in 1841, it forms part of the family Accipitridae (hawks and eagles) and is most closely related to the square-tailed kite (Lophoictinia isura). It is a versatile hunter known for its special skill in cracking eggs. The species is common throughout most of its range.
Intermediate in body size between the well-known larger wedge-tailed eagle (Aquila audax) and the smaller little eagle (Hieraaetus morphnoides), the black-breasted buzzard is one of Australia's largest birds of prey and one of the world's largest kites alongside the red kite, which is slightly less heavy but has a longer total length. [3] [4] An adult black-breasted buzzard measures 51 to 61 cm (20 to 24 in) in height including its short square tail. [3] [5] The buzzard's outstretched wingspan measures 141 to 156 cm (4 ft 8 in to 5 ft 1 in), [3] rendering the bird distinctive in flight as its wings are conspicuously long relative to its stout body and tail. [6] Buzzards appear sexually monomorphic (identical in physical appearance), although the adult female is slightly larger, weighing approximately 1,330 g (2.93 lb) compared to the 1,196 g (2.637 lb) of the adult male. [3] The weight range for the species is from 1,150 to 1,600 g (2.54 to 3.53 lb). [7] [8] It is most closely related to the Square-tailed kite (Lophoictinia isura). [5]
The black-breasted buzzard is striking in appearance due to the distinctive markings of the adult plumage. From the underside, the mainly black colouring of the body and wings is contrasted by thick white panels near the end of the wings. From above, the black plumage is broken by a rich mottled red across the back and shoulders. Birds in the immature and juvenile phases of growth display pale brown colouring, with dark to black streaks increasing with age. Chicks have white coloured down, described as ‘hair-like’ on their heads. [3] Adult birds may be individually identified during flight by broken or missing flight feathers, or when perched closely together by subtle differences in the red of the back and shoulders. [5]
The common call of the black-breasted buzzard is described as a repeated hoarse yelping [3] or short sharp yap or yelp. [5] Adult females also make a soft drawn-out wheezing call to solicit their mate to copulate, undertake nest-building, forage for food and defend the nest. Young buzzards also use a wheezing call to solicit food from their parents. [5]
The black-breasted buzzard is widely but sparsely distributed throughout northern and inland Australia [3] in areas with less than 500 mm annual rainfall. [6] The buzzard's range stretches from north-eastern South Australia, north-western New South Wales, northern Queensland, the Northern Territory and the north-western exterior of Western Australia. The buzzard does not occur in Victoria, the Australian Capital Territory or Tasmania, due to their wetter temperate climates. [6]
Found to occur in wooded and open habitats, the black-breasted buzzard is most commonly observed in riparian forests and tall-open woodlands surrounded by mid-dense shrublands. [3] [9] In a study of raptor habitat association in central Australia, it was most commonly observed in River Red Gum (Eucalyptus camaldulensis) open woodland, demonstrating a significant preference for this habitat type. [9]
The black-breasted buzzard hunts a variety of reptiles, small mammals and birds, and raids bird nests to steal eggs and nestlings, including those of other raptor species. [9] Not regarded as a specialist or highly proficient hunter, the buzzard's diet often includes carrion of large mammals that may be sourced along roads, tracks and creek lines. [6] [9]
It uses a variety of methods to search for food, including soaring in transects over low vegetation, undertaking cooperative hunting with conspecifics and observing from high up on unconcealed perches. [9] The buzzard may drop, pounce, dive or glide to attack its prey. [9]
Skilled in terrestrial hunting, [9] the black-breasted buzzard is famous for its use of stones to crack the eggs of large ground-nesting birds such as the Emu (Dromaius novaehollandiae), Brolga (Grus rubicundus) and Australian Bustard (Ardeotis australis). Stones are either dropped onto or thrown at the eggs to break them open, allowing the buzzard to access the contents for food. The buzzard may also use its beak to crack eggs directly. [10]
The black-breasted buzzard is usually monogamous, forming lifelong pair-bonds. [11] The buzzard nests in trees of notable height and girth, larger and more independent from others generally available. [12] The trees may be dead with bare exposed limbs, or live and foliated, with nests positioned in prominent forks high up in the canopies. [5] [12] Both parents contribute equally to nest-building and often work together in unison on the nest structure. Nests are constructed from dead sticks and leafy branches, with materials gathered from the ground or broken off trees and carried to the nest site in feet or beak. Nest dimensions have been measured at 1.2m long x 0.8m wide x 0.4m deep. [5] Nest dimensions are larger than that of any other raptor species, including the larger-bodied wedge-tailed eagle. [12]
The black-breasted buzzard lays its eggs from August to October, with breeding believed to be stimulated by increased day length, as well as by increased food availability often linked to rainfall events. [6] [12] A usual clutch comprises two eggs laid at an interval of approximately 8–13 days and incubated for a period of 32–38 days. [5] Nestlings remain in the nest for between 68–73 days before fledging around December. [5] [12] The female tends the nest for the majority of time while the male hunts and returns food. [5] Usually only one chick per nest survives to fledge each season. [12]
Fresh leafy branches, separate from the basic nest structure, are added periodically during the breeding cycle. [5] This greenery is thought to serve medicinal purposes, such as to aid in parasite and pathogen control, and or to reduce bacteria. [5] [13] [14] Other hypotheses suggest the greenery may play a role in courtship, and or assist in nestling development. Although known to occur in a variety of avian species from a range of climates and habitats around the world, this behaviour is not yet fully understood. [14]
The current IUCN Red List ranks the black-breasted buzzard of Least Concern. [1] [11] [15] While it is not listed as a conservation concern by the Australian Commonwealth, [6] it is listed as Vulnerable in New South Wales and Rare in South Australia. [6] [15] Recent studies have assessed the black-breasted buzzard as one of many avian species of particular conservation concern in the Western Division of New South Wales. [16] The global population estimate for the black-breasted buzzard is uncertain, varying between 1000–10,000 individuals. [15]
There has been a significant decline amongst Australian raptor species including the black-breasted buzzard since European settlement in the late 1700s. [17] Historic records indicate the black-breasted buzzard became extinct in some areas of its former range by as early as the 1930s. [17] Causes of population declines in raptor species of the arid and semi-arid regions of Australia include broad-scale landscape changes due to extensive pastoralism and clearing of native vegetation; overgrazing by stock, feral animals and increased kangaroo populations; altered fire regimes; the introduction of destructive feral predators such as the house cat (Felis catus) and red fox (Vulpes vulpes); and the cessation of traditional Aboriginal hunting and land management practices. [16] [17] Intense periods of drought through the 1900s and 2000s are known to have compounded the impacts on already stressed raptor communities. [9] [17]
Inadvertent poisoning of raptors through ingestion of prey killed by toxins is a well-known threat to raptor species worldwide [18] [19] [20] and a likely contributor to their decline in Australia. [6] [21] Such toxins are frequently introduced to the environment by humans to combat pest animals and plague insects. [6] [18] [19] [20] [21] Other potential causes of decline include direct persecution by humans in the form of illegal egg collection and shooting [6] which has been recorded in a number of Australian raptor species, for example the osprey (Pandion haliaetus) in South Australia. [22] and Europe [21] and the Tasmanian wedge-tailed eagle (Aquila audax fleayi). [23]
Climate change leading to increased periods of drought in the arid and semi-arid areas of Australia [24] [25] is a concern for the survival of many raptors species, particularly those with specialist diets dependent on a limited array of prey species. [9] The black-breasted buzzard has a varied diet including carrion that may afford it some resilience in the face of intense drought when carcasses of perished large mammals become abundant. [9] However, it also has a year-round preference for living and nesting in the riparian zones of creek lines and drainage channels. [9] [12] As these tend to dry up under drought conditions, [24] [25] resultant habitat loss is likely to threaten the buzzard's reproductive viability and survival. [6] More frequent and intense wildfire events will also increasingly contribute to the decline of large trees and potential black-breasted buzzard habitat. [12] [16]
A program of landscape conservation that engages all land managers and stakeholders and includes the protection of existing habitat and revegetation of lost habitat, is considered the first step in protecting the black-breasted buzzard, its relatives and the overall biodiversity of arid and semi-arid Australia. [6] [16] [24] [25]
The common buzzard is a medium-to-large bird of prey which has a large range. It is a member of the genus Buteo in the family Accipitridae. The species lives in most of Europe and extends its breeding range across much of the Palearctic as far as northwestern China, far western Siberia and northwestern Mongolia. Over much of its range, it is a year-round resident. However, buzzards from the colder parts of the Northern Hemisphere as well as those that breed in the eastern part of their range typically migrate south for the northern winter, many journeying as far as South Africa.
The Accipitridae is one of the three families within the order Accipitriformes, and is a family of small to large birds of prey with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium-sized mammals, with a number feeding on carrion and a few feeding on fruit. The Accipitridae have a cosmopolitan distribution, being found on all the world's continents and a number of oceanic island groups. Some species are migratory. The family contains 255 species which are divided into 70 genera.
The wedge-tailed eagle is the largest bird of prey in the continent of Australia. It is also found in southern New Guinea to the north and is distributed as far south as the state of Tasmania. Adults of the species have long, broad wings, fully feathered legs, an unmistakable wedge-shaped tail, an elongated upper mandible, a strong beak and powerful feet. The wedge-tailed eagle is one of 12 species of large, predominantly dark-coloured booted eagles in the genus Aquila found worldwide. Genetic research has clearly indicated that the wedge-tailed eagle is fairly closely related to other, generally large members of the Aquila genus. A large brown-to-black bird of prey, it has a maximum reported wingspan of 2.84 m and a length of up to 1.06 m.
The white-bellied sea eagle, also known as the white-breasted sea eagle, is a large diurnal bird of prey in the family Accipitridae. Originally described by Johann Friedrich Gmelin in 1788, it is closely related to Sanford's sea eagle of the Solomon Islands, and the two are considered a superspecies. A distinctive bird, the adult white-bellied sea eagle has a white head, breast, under-wing coverts and tail. The upper parts are grey and the black under-wing flight feathers contrast with the white coverts. The tail is short and wedge-shaped as in all Haliaeetinae species. Like many raptors, the female is larger than the male, and can measure up to 90 cm (35 in) long with a wingspan of up to 2.2 m (7.2 ft), and weigh 4.5 kg (9.9 lb). Immature birds have brown plumage, which is gradually replaced by white until the age of five or six years. The call is a loud goose-like honking.
The black-shouldered kite, also known as the Australian black-shouldered kite, is a small raptor found in open habitats throughout Australia. It resembles similar species found in Africa, Eurasia and North America, including the black-winged kite, a species that has in the past also been called "black-shouldered kite". Measuring around 35 cm (14 in) in length, with a wingspan of 80–100 cm (31–39 in), the adult black-shouldered kite has predominantly grey-white plumage and prominent black markings above its red eyes. It gains its name from the black patches on its wings. The primary call is a clear whistle, uttered in flight and while hovering. It can be confused with the related letter-winged kite in Australia, which is distinguished by the striking black markings under its wings.
The rough-legged buzzard (Europe) or rough-legged hawk (Buteo lagopus) is a medium-large bird of prey. It is found in Arctic and Subarctic regions of North America, Europe, and Russia during the breeding season and migrates south for the winter. It was traditionally also known as the rough-legged falcon in such works as John James Audubon's The Birds of America.
The crested honey buzzard is a bird of prey in the family Accipitridae, which also includes many other diurnal raptors such as kites, eagles, and harriers. Pernis ptilorhynchus has six subspecies. As a medium-sized raptor, their size ranges between 57–60 cm (22–24 in). They are also known as the Oriental, Asiatic, or Eastern honey buzzard. The name is derived from its diet, which consists mainly of the larvae of bees and wasps extracted from honey combs.
The red goshawk is probably the rarest Australian bird of prey. It is found mainly in the savanna woodlands of northern Australia, particularly near watercourses. It takes a broad range of live prey, mostly birds.
The lizard buzzard or lizard hawk, is a bird of prey in the family Accipitridae. It is native to Sub-Saharan Africa. Despite its name, it may be more closely related to the Accipiter hawks than the Buteo buzzards.
The long-legged buzzard is a bird of prey found widely in several parts of Eurasia and in North Africa. This species ranges from Southeastern Europe down to East Africa to the northern part of the Indian subcontinent. The long-legged buzzard is a member of the genus Buteo, being one of the larger species therein. Despite being relatively powerful, it is considered a rather sluggish raptor overall. Like most buzzards, it prefers small mammals such as rodents, including gerbils, ground squirrels, voles and rats, also taking reptiles, birds and insects as well as carrion. Adaptable to a variety of habitats, long-legged buzzards may nest on a variety of surfaces, including rocks, cliffs and trees. it is a typical buzzard in its reproductive biology. The long-legged buzzard is widely distributed and appears to be quite stable in population. Therefore, it is considered as Least Concern by the IUCN.
The square-tailed kite is a medium-sized bird of prey in the family Accipitridae, which also includes many other diurnal raptors such as kites, eagles and harriers.
The black falcon is a medium-large falcon that is endemic to Australia. It can be found in all mainland states and territories and yet is regarded as Australia's most under-studied falcon.
The little eagle is a very small eagle endemic to Australia.
The Papuan eagle is a large bird of prey. It is also known by several other names, including Papuan harpy eagle, New Guinea eagle, New Guinea harpy eagle, or kapul eagle, the latter name from the local name for a usually arboreal, marsupial that the eagle is known to regularly hunt. This is an endemic species to New Guinea, and it can occasionally be found throughout the island. This is a forest-dwelling species, usually occurring in mature rainforest. The Papuan eagle is a fairly little-known species for a large eagle; however, it is known to prey on a wide range of prey, probably by and large mammals and birds from small to quite large sizes. What little study has been conducted about their breeding habits suggests they nest in a large forest tree, perhaps every other year. The Papuan eagle is probably naturally scarce, but it is under the threat of habitat destruction by deforestation, as well as hunting. Due to its small and declining population, the species has been classified as vulnerable by the IUCN.
The letter-winged kite is a small, rare and irruptive bird of prey that is found only in Australia. Measuring around 35 cm (14 in) in length with a wingspan of 84–100 cm (33–39 in), the adult letter-winged kite has predominantly pale grey and white plumage and prominent black rings around its red eyes. Its name derives from its highly distinctive black underwing pattern of a shallow 'M' or 'W' shape, visible when in flight. This distinguishes it from the otherwise similar black-shouldered kite. This species is also the only nocturnal species within the order Accipitriformes despite few differences found in its visual anatomy to other closely related kites.
The jackal buzzard is a fairly large African bird of prey. The taxonomy of this species has caused some confusion in the past and it almost certainly belongs in a species complex with other African Buteo species. Some taxonomists have considered this species, the Archer's buzzard, and the augur buzzard to be the same superspecies. Many taxonomists consider them all to be distinct, having different calls, different home ranges and variations in plumage. This is a species that lives among mountains, and on adjacent savanna and grassland. It is resident and non-migratory throughout its range.
The black honey-buzzard, also commonly known as the New Britain Honey-Buzzard, is a large raptor of the family Accipitridae. Standing at around 50 cm (20 in) tall, the adult black honey-buzzard has a dark head and body, with striking white bands on its tail and flight feathers. When in flight, the buzzard can be recognized by its long wings and noticeably large secondary feathers. It is thought to be sedentary, with a range limited to the island of New Britain in Papua New Guinea, where it is endemic. Due to its remote habitat and tendency to remain in densely forested areas, there is currently much to learn about this striking species.
Henicopernis is a genus of bird of prey in the family Accipitridae.
The black-and-chestnut eagle is a large South American species of bird of prey in the family Accipitridae. It is sometimes called Isidor's eagle. It is often placed in the monotypic genus Oroaetus. However, recent genetic testing indicates that this species is fairly closely related to Spizaetus species and thus the species should be included in that genus. The black-and-chestnut eagle is a typical forest raptor, hunting primarily small to medium-sized mammals and birds and constructing a large nest in a tall tree. Unfortunately, the twin causes of habitat destruction and persecution, justified or not as an occasional poultry killer, have caused strong population declines and the black-and-chestnut eagle is considered to be an Endangered species by the IUCN.
The eastern osprey is a diurnal, fish-eating bird of prey. They live in Oceania at coastal regions of the Australian continent, the Indonesian islands, New Guinea, and the Philippines. It is usually sedentary and pairs breed at the same nest site, building up a substantial structure on dead trees or limbs. The subspecies resides in a habitat close to coasts and estuaries that provide opportunities for fishing. In 2022, it was considered a defunct species by the IOC, due to its low genetic divergences and absence in morphological differences. The eastern osprey's diet consists mostly of vertebrate fish species. It possesses specialised physical characteristics and exhibits unique behaviour to assist in hunting and catching prey.