White-winged chough | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Passeriformes |
Family: | Corcoracidae |
Genus: | Corcorax Lesson, 1831 |
Species: | C. melanorhamphos |
Binomial name | |
Corcorax melanorhamphos (Vieillot, 1817) | |
The white-winged chough (Corcorax melanorhamphos) is one of only two surviving members of the Australian mud-nest builders family, Corcoracidae, and is the only member of the genus Corcorax. It is native to southern and eastern Australia and is an example of convergent evolution as it is only distantly related to the European choughs that it closely resembles in shape, and for which it was named.
The white-winged chough was first described by French naturalist Louis Pierre Vieillot in 1817 as Coracia melanorhamphos, [2] other names given include Pyrrhocorax leucopterus by Dutch zoologist Coenraad Jacob Temminck in 1820, [3] and Corcorax australis by French naturalist René Lesson in 1830. [4] before the current name was settled by Gregory Mathews in 1912. [5] The specific epithet is derived from the Ancient Greek words melano- 'black' and rhamphos 'beak'. [6]
It is placed in the family known as the mud-nest builders or Corcoracidae, written as Grallinidae in older books before the removal of the genus Grallina to the family Monarchidae. [7] It is one of two remaining species, with the apostlebird (Struthidea cinerea), which differs in appearance but exhibits many behavioural similarities. [7] The mudnest builder family Corcoracidae itself is now placed in a narrower 'Core corvine' group, which contains the crows and ravens, shrikes, birds of paradise, fantails, monarch flycatchers, and drongos. [8]
It is only distantly related to the red-billed chough (Pyrrhocorax pyrrhocorax) and Alpine chough (P. graculus), which are members of the crow family Corvidae. The similarities in appearance of dark plumage and downturned bill are the result of convergent evolution.
White-winged choughs are easily recognised but often mistaken for "crows" (such as the Australian raven). The white-winged chough is a large, black bird—at about 45 cm (18 in) only a little smaller than a raven or a little larger than an Australian magpie —but has red eyes and a finer, slightly down-curved beak, similar to a European chough. These red eyes become swollen and brighter in colour when the bird is excited. In flight the large white patches in the wings are immediately obvious, and explain the descriptive part of their common name. [9]
Their calls consist primarily of a grating alarm call and a descending piping call. The latter call is diagnostic for the bird in the wild, being significantly different in timbre and melody to that of other birds sharing their habitat.
Flight is a mixture of a slow, deep flapping and short glides: unlike their European namesakes, white-winged choughs are not particularly strong or agile fliers and spend the great majority of their time on the ground, foraging methodically through leaf litter for worms, insects, grain, and snails in a loose group, walking with a distinctive swagger, and calling softly to one another every few seconds. A rich find is the cause of general excitement and all come running in to share in it. The family group walks several kilometres each day through its large territory, foraging as it goes, taking to the air only if disturbed.
Choughs are territorial and highly social, living in flocks of from about 4 up to about 20 birds, usually all the offspring of a single pair. Because raising of young is a group effort bands of chough may kidnap fledglings from other family groups so that they will be able to help them to raise their chicks next year. [10] [11]
The white-winged chough will forage in litter and rotten wood for termites and beetles. Although birds have eaten pieces of apple placed out for them on feeding tables, they have not been recorded eating fruit on trees. [12] This species has been observed eating cherry tomatoes, whole, in eastern Australian, Newcastle region.[ citation needed ]
The diet is varied, the white-winged chough eats seeds of various grasses (Poaceae), Gahnia grandis , Atriplex , Epacris , Hibbertia , Solanum , Acacia and Exocarpos species, as well as introduced species such as the cursed thistle ( Cirsium arvense ), roadside thistle ( C. vulgare ), winter honeysuckle ( Lonicera fragrantissima ), Convolvulus and Oxalis species. Berries of the introduced Cotoneaster and Crataegus are also consumed. It eats a wide variety of arthropods, including centipedes, millipedes and many types of insect—beetles, cockroaches, termites, grasshoppers and crickets, flies, butterflies and moths, and ants, bees and wasps. [13] In some areas, it will readily approach tourist sites to find supplementary food. [14]
Nesting and breeding is communal, all members of the family helping to raise the young - a process that takes several years, as young birds must learn the art of finding food in the dry Australian bush. Larger families have a better chance of breeding success: so much so that given the opportunity choughs will kidnap the youngsters of neighboring families in order to recruit them to the team.
Breeding season is from August to December. The nest is a deep cup-shaped structure made of grasses held together with mud or sometimes manure in a tree fork up to 10 metres above the ground. Three to five cream-coloured eggs sparsely splotched with dark brown and lavender shades are laid measuring 30 mm x 40 mm. [15]
There is one report of white-winged choughs occupying and using a nest which was likely to have been built by the Australian magpie. However, this was unable to be confirmed as the nest was not witnessed being built. [16]
All members of a family take turns to incubate, preen, and feed youngsters, and all cooperate in defending the nest against predators. However, the juveniles, who are highly inefficient foragers, have been observed to engage in deception; they bring food back to the nest and make to feed nestlings, but instead wait until unobserved, and then eat it themselves. This behaviour disappeared when food sources were artificially supplemented. [17] There are three main threats to young choughs: starvation; predation by nest-robbing birds, particularly currawongs; and sabotage by neighbouring chough families anxious to protect their food supply by restricting competition. Larger family groups are better able to deal with all three threats.
Nesting in communal groups is essential: pairs, or even trios, of birds are almost never successful in raising young. Young take six to seven months to reach independence – a significant time-span for birds – but they repay the long investment by returning to the nest the next year and helping raise the next generation. [18]
Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, ravens, rooks, magpies, jackdaws, jays, treepies, choughs, and nutcrackers. In colloquial English, they are known as the crow family or corvids. Currently, 135 species are included in this family. The genus Corvus containing 47 species makes up over a third of the entire family. Corvids (ravens) are the largest passerines.
The red-billed chough, Cornish chough or simply chough, is a bird in the crow family, one of only two species in the genus Pyrrhocorax. Its eight subspecies breed on mountains and coastal cliffs from the western coasts of Ireland and Britain east through southern Europe and North Africa to Central Asia, India and China.
The Alpine chough or yellow-billed chough is a bird in the crow family, one of only two species in the genus Pyrrhocorax. Its two subspecies breed in high mountains from Spain eastwards through southern Europe and North Africa to Central Asia and Nepal, and it may nest at a higher altitude than any other bird. The eggs have adaptations to the thin atmosphere that improve oxygen take-up and reduce water loss.
The Australian raven is a passerine corvid bird native to Australia. Measuring 46–53 centimetres (18–21 in) in length, it has an all-black plumage, beak and mouth, as well as strong, greyish-black legs and feet. The upperparts of its body are glossy, with a purple-blue, greenish sheen; its black feathers have grey bases. The Australian raven is distinguished from the Australian crow, and other related corvids, by its long chest feathers, or throat hackles, which are prominent in mature birds. Older individuals and subadults have white irises, while the younger birds' eyes display blue inner rims; hatchlings and young birds have brown, dark irises until about fifteen months of age, at which point their irises become hazel-coloured, with an inner blue rim around each pupil, this lasting until they are roughly 2.5 to 3 years of age. Nicholas Aylward Vigors and Thomas Horsfield described the Australian raven in 1827, its species name coronoides highlighting its similarity with the carrion crow. Two subspecies are recognised, which differ slightly in their vocalisations, and are quite divergent, genetically.
The forest raven, also commonly known as the Tasmanian raven, is a passerine bird in the family Corvidae native to Tasmania and parts of southern Victoria, such as Wilsons Promontory and Portland. Populations are also found in parts of New South Wales, including Dorrigo and Armidale. Measuring 50–53 cm (20–21 in) in length, it has all-black plumage, beak and legs. As with the other two species of raven in Australia, its black feathers have grey bases. Adults have white irises; younger birds have dark brown and then hazel irises with an inner blue rim. New South Wales populations are recognised as a separate subspecies C. tasmanicus boreus, but appear to be nested within the Tasmanian subspecies genetically.
The willie wagtail, scientific name Rhipidura leucophrys, is a passerine bird native to Australia, New Guinea, the Solomon Islands, the Bismarck Archipelago, and Eastern Indonesia. It is a common and familiar bird throughout much of its range, living in most habitats apart from thick forest. Measuring 19–21.5 cm in length, the willie wagtail is contrastingly coloured with almost entirely black upperparts and white underparts; the male and female have similar plumage.
There are two species of passerine birds commonly called chough that constitute the genus Pyrrhocorax of the Corvidae (crow) family of birds. These are the red-billed chough, and the Alpine chough. The white-winged chough of Australia, despite its name, is not a true chough but rather a member of the family Corcoracidae and only distantly related.
The black currawong, also known locally as the black jay, is a large passerine bird endemic to Tasmania and the nearby islands within the Bass Strait. One of three currawong species in the genus Strepera, it is closely related to the butcherbirds and Australian magpie within the family Artamidae. It is a large crow-like bird, around 50 cm (20 in) long on average, with yellow irises, a heavy bill, and black plumage with white wing patches. The male and female are similar in appearance. Three subspecies are recognised, one of which, Strepera fuliginosa colei of King Island, is vulnerable to extinction.
The pied currawong is a black passerine bird native to eastern Australia and Lord Howe Island. One of three currawong species in the genus Strepera, it is closely related to the butcherbirds and Australian magpie of the family Artamidae. Six subspecies are recognised. It is a robust crowlike bird averaging around 48 cm (19 in) in length, black or sooty grey-black in plumage with white undertail and wing patches, yellow irises, and a heavy bill. The male and female are similar in appearance. Known for its melodious calls, the species' name currawong is believed to be of indigenous origin.
Corcoracidae is a family of passerine birds known as the Australian mudnesters. The family has sometimes been called Struthideidae in the past; however, despite Struthideidae being an older name than Corcoracidae, the latter name takes precedence. It contains just two species in two genera, the white-winged chough and the apostlebird. Both are endemic to Australia.
Temminck's stint is a small wader. This bird's common name and Latin binomial commemorate the Dutch naturalist Coenraad Jacob Temminck. The genus name is from Ancient Greek kalidris or skalidris, a term used by Aristotle for some grey-coloured waterside birds.
The Eurasian crag martin or just crag martin is a small passerine bird in the swallow family. It is about 14 cm (5.5 in) long with ash-brown upperparts and paler underparts, and a short, square tail that has distinctive white patches on most of its feathers. It breeds in the mountains of southern Europe, northwestern Africa and across the Palearctic. It can be confused with the three other species in its genus, but is larger with brighter tail spots and different plumage tone. Many European birds are resident, but some northern populations and most Asian breeders are migratory, wintering in northern Africa, the Middle East or India.
The striated pardalote is the least colourful and most common of the four pardalote species. Other common names include pickwick, wittachew and chip-chip. It is a very small, short-tailed bird that is more often heard than seen, foraging noisily for lerps and other small creatures in the treetops.
The little cormorant is a member of the cormorant family of seabirds. Slightly smaller than the Indian cormorant it lacks a peaked head and has a shorter beak. It is widely distributed across the Indian Subcontinent and extends east to Java, where it is sometimes called the Javanese cormorant. It forages singly or sometimes in loose groups in lowland freshwater bodies, including small ponds, large lakes, streams and sometimes coastal estuaries. Like other cormorants, it is often found perched on a waterside rock with its wings spread out after coming out of the water. The entire body is black in the breeding season but the plumage is brownish, and the throat has a small whitish patch in the non-breeding season. These birds breed gregariously in trees, often joining other waterbirds at heronries.
The monarchs comprise a family of over 100 passerine birds which includes shrikebills, paradise flycatchers, and magpie-larks.
The apostlebird, also known as the grey jumper, lousy jack or happy family, is a quick-moving, gray or black bird about 33 cm (13 in) long. It is a native to Australia where it roams woodlands, eating insects and seeds at, or near, ground level. Apostlebirds often travel in groups of about 12; for this reason, they were named after the 12 Biblical apostles.
The white-winged fairywren is a species of passerine bird in the Australasian wren family, Maluridae. It lives in the drier parts of Central Australia; from central Queensland and South Australia across to Western Australia. Like other fairywrens, this species displays marked sexual dimorphism and one or more males of a social group grow brightly coloured plumage during the breeding season. The female is sandy-brown with light-blue tail feathers; it is smaller than the male, which, in breeding plumage, has a bright-blue body, black bill, and white wings. Younger sexually mature males are almost indistinguishable from females and are often the breeding males. In spring and summer, a troop of white-winged fairywrens has a brightly coloured older male accompanied by small, inconspicuous brown birds, many of which are also male. Three subspecies are recognised. Apart from the mainland subspecies, one is found on Dirk Hartog Island, and another on Barrow Island off the coast of Western Australia. Males from these islands have black rather than blue breeding plumage.
Communal roosting is an animal behavior where a group of individuals, typically of the same species, congregate in an area for a few hours based on an external signal and will return to the same site with the reappearance of the signal. Environmental signals are often responsible for this grouping, including nightfall, high tide, or rainfall. The distinction between communal roosting and cooperative breeding is the absence of chicks in communal roosts. While communal roosting is generally observed in birds, the behavior has also been seen in bats, primates, and insects. The size of these roosts can measure in the thousands to millions of individuals, especially among avian species.
The Pacific robin, is a red-breasted Australasian robin in the passerine bird genus Petroica found in Melanesia and Polynesia. It is similar in plumage to the scarlet robin of Australia, and until recently the two were considered conspecific until split in 1999 by Schodde and Mason. Thirteen subspecies of Pacific robin are currently recognised, and these subspecies display considerable variation in plumage, foraging preferences, and habitat. The Norfolk robin was previously considered a subspecies of the Pacific robin, but is now considered a distinct species.
There are usually White-winged Choughs stealing scraps from the tables.
David Attenborough, The Life of Birds, Episode 9, 35 mins ff.