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The Australian raven (''Corvus coronoides'') is a passerine bird in the genus ''Corvus'' native to much of southern and northeastern Australia. Measuring in length, it has all-black plumage, beak and mouth, as well as strong grey-black legs and feet. The upperparts are glossy, with a purple, blue or green sheen, and its black feathers have grey bases. The Australian raven is distinguished from the Australian crow species by its throat hackles, which are prominent in adult birds. Older adult individuals have white irises, younger adults have a white irises with an inner blue rim, while younger birds have dark brown irises until fifteen months of age, and hazel irises with an inner blue rim around each pupil until age two years and ten months. Nicholas Aylward Vigors and Thomas Horsfield described the Australian raven in 1827, its species name highlighting its similarity with the carrion crow (''C. corone''). Two subspecies are recognised, which differ slightly in calls and are quite divergent genetically. The preferred habitat is open woodland and transitional zones. It has adapted well to urban environments and is a common city bird in Sydney, Canberra and Perth. An omnivorous and opportunistic feeder, it eats a wide variety of plant and animal material, as well as food waste from urban areas. In eastern Australia its range is strongly correlated with the presence of sheep, and it has been blamed for killing lambs. However, this is very rare, and the raven most often scavenges for afterbirth and stillborn animals as well as newborn lamb faeces. The Australian raven is territorial, with pairs generally bonding for life. Breeding takes place between July and September, with almost no variation across its range. The nest is a bowl-shaped structure of sticks sited high in a tree, or occasionally in a man-made structure such as a windmill or building. ==Taxonomy and naming== The Australian raven was first described by Nicholas Aylward Vigors and Thomas Horsfield in 1827, when they reported George Caley's early notes on the species from the Sydney district. Its specific epithet ''coronoides'' "crow-shaped" is derived from the Greek ''corone''/κορόνη "crow" and ''eidos''/είδος "shape" or "form". The two naturalists regarded the Australian raven as very similar in appearance to the carrion crow (''C. corone'') of Europe, though they noted it was larger with a longer bill. They did not give it a common name.〔 The location where the type specimen was collected is not recorded, but thought to be in the Parramatta district.〔 Christian Ludwig Brehm described ''Corvus affinis'' in 1845, later determined to be this species. In his 1865 ''Handbook to the Birds of Australia'', John Gould recognised only one species of corvid in Australia, ''Corvus australis'', which he called the white-eyed crow. He used Johann Friedrich Gmelin's 1788 name, which predated Vigors and Horsfield's description. In 1877 Richard Bowdler Sharpe recognised two species, but recorded that the feather bases of the type specimen of ''C. coronoides'' were white. He named ''C. coronoides'' as the "crow" and ''C. australis'' (as ''Corone australis'') the "raven".〔 Scottish naturalist William Robert Ogilvie-Grant corrected this in 1912 after re-examining the type specimen, clarifying the species as ''C. coronoides'' (raven, and incorporating little and forest ravens) and ''C. cecilae'' (Torresian crow). Gregory Mathews described the western subspecies ''perplexus'' in 1912, naming it the southwestern crow and noting that it was smaller than the nominate subspecies. He called ''C. coronoides coronoides'' the eastern crow, listing its range as New South Wales, and described what is now the Australian crow as another subspecies, ''C. coronoides cecilae'', calling it the north-western crow and recording its range as northwestern Australia. In the same work he listed the raven as ''Corvus marianae'', with a type specimen from Gosford and listing its range as New South Wales. He listed the little raven and forest raven as subspecies. Mathews had erected ''C. marianae'' in 1911 as the name after declaring ''Corvus australis'' Gould to be preoccupied; French-American ornithologist Charles Vaurie acted as First Revisor under Article 24 of the International Code of Zoological Nomenclature (ICZN) Code and discarded ''C. australis'' as a junior homonym—in 1788, Gmelin had used the same binomial name to describe the black nunbird—to preserve the stability of the name. This has been followed by later authors. German ornithologist Erwin Stresemann lumped all Australian corvids plus other species as far as India into a single species, ''C. coronoides'', as he believed there was intergradation between all characteristics such as iris colour, colour of feather bases and plumage. This was hotly disputed by Mathews. The official RAOU checklist listed three species (Australian raven, Torresian crow and little crow), with the little raven recognised as a fourth species in 1967 and forest raven in 1970. Streseman described ''C. difficilis'' in 1943 from a single specimen, now thought to have been an unusual Australian raven or an Australian raven/Torresian crow hybrid.〔 Alternative names sometimes seen include southern raven, southern crow and Kelly, the last thought to have alluded to the Kelly Gang, though did not appear until the 1920s. Southern crow was considered by the RAOU before Australian raven was adopted as the official name for the species in 1926. The term "crow" is colloquially applied to any or all species of Australian corvid.〔 The Australian raven was called ''wugan'' by the local Eora and Darug inhabitants of the Sydney Basin. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Australian raven」の詳細全文を読む スポンサード リンク
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