nomes no trilho de navegação
Les especies d'aves con nome común en llingua asturiana márquense como NOA. En casu contrariu, conséñase'l nome científicu o de la SEO.
'''Corvus coronoides ye'l más grande representante n'Australia del xéneru Corvus y una de les especies de cuervos más conocíes n'Australia.
El cuervu australianu grande describióse per primer vegada por Nicholas Aylward Vigors y Thomas Horsfield en 1827;[1] el so nome "crononoides", "its specific epithet coronoides "forma de cuervu" deriva del griegu corone/κορονη, cuervu y eidos/ειδος, forma.[2]
Los sos parientes más cercanos son otres cuatro especies de cuervu d'Australia, que son el Cuervu Torresiano y el Cuervu pequeñu, asina mesmu como'l cuervu del monte y el Corvus mellori.
Con 52 centímetros, un cuervu australianu grande adultu ye un ave negra con un iris blancu. Les plumes que tán nel llombu son más grandes que les de cualesquier otra especie de cuervu. Los mozos paecer a los adultos, sacante en que tienen güeyos escuros.[3]
Esta páxina forma parte del wikiproyeutu Aves, un esfuerciu collaborativu col fin d'ameyorar y organizar tolos conteníos rellacionaos con esti tema. Visita la páxina d'alderique del proyeutu pa collaborar y facer entrugues o suxerencies. Les especies d'aves con nome común en llingua asturiana márquense como NOA. En casu contrariu, conséñase'l nome científicu o de la SEO. '''Corvus coronoides ye'l más grande representante n'Australia del xéneru Corvus y una de les especies de cuervos más conocíes n'Australia.
Corvus coronoides[1] a zo ur spesad golvaneged eus ar c'herentiad Corvidae.
Anvet e voe Corvus Coronoides (kentanv) da gentañ-penn (e 1827) gant an daou skiantour stadunanat Thomas Horsfield (1773-1859) hag iwerzhonat Nicholas Aylward Vigors (1785-1840).
Hollzebrer eo ar spesad.
Ar spesad a gaver an daou isspesad anezhañ en Aostralia[2] :
a vo kavet e Wikimedia Commons.
Corvus coronoides a zo ur spesad golvaneged eus ar c'herentiad Corvidae.
Anvet e voe Corvus Coronoides (kentanv) da gentañ-penn (e 1827) gant an daou skiantour stadunanat Thomas Horsfield (1773-1859) hag iwerzhonat Nicholas Aylward Vigors (1785-1840).
Aderyn a rhywogaeth o adar yw Cigfran Awstralia (sy'n enw benywaidd; enw lluosog: cigfrain Awstralia) a adnabyddir hefyd gyda'i enw gwyddonol Corvus coronoides; yr enw Saesneg arno yw Australian raven. Mae'n perthyn i deulu'r Brain (Lladin: Corvidae) sydd yn urdd y Passeriformes.[1]
Talfyrir yr enw Lladin yn aml yn C. coronoides, sef enw'r rhywogaeth.[2] Mae'r rhywogaeth hon i'w chanfod yn Awstralia.
Mae'r cigfran Awstralia yn perthyn i deulu'r Brain (Lladin: Corvidae). Dyma rai o aelodau eraill y teulu:
Rhestr Wicidata:
rhywogaeth enw tacson delwedd Aderyn rhisgl Falcunculus frontatus Aradrbig Eulacestoma nigropectus
.JPG)
Aderyn a rhywogaeth o adar yw Cigfran Awstralia (sy'n enw benywaidd; enw lluosog: cigfrain Awstralia) a adnabyddir hefyd gyda'i enw gwyddonol Corvus coronoides; yr enw Saesneg arno yw Australian raven. Mae'n perthyn i deulu'r Brain (Lladin: Corvidae) sydd yn urdd y Passeriformes.
Talfyrir yr enw Lladin yn aml yn C. coronoides, sef enw'r rhywogaeth. Mae'r rhywogaeth hon i'w chanfod yn Awstralia.
Australsk krage (latin: Corvus coronoides) er en spurvefugl, der lever i Australien.
Taksonomi fra Wikispecies Australsk krage (latin: Corvus coronoides) er en spurvefugl, der lever i Australien.
Die Neuhollandkrähe (Corvus coronoides) ist ein Vogel aus der Gattung der Raben und Krähen (Corvus). Sie kommt ausschließlich in Australien und einigen der Küste vorgelagerten Inseln vor. Sie ist die in Australien am weitesten verbreitete und bekannteste Art der Rabenvögel.[1] Neuhollandkrähen verwerten eine große Bandbreite Nahrungsquellen und sind sehr anpassungsfähig. Die IUCN stuft ihre Bestandssituation als ungefährdet (least concern) ein.[2]
Zwischen den Geschlechtern der Neuhollandkrähe besteht weder in der Gefiederfärbung noch im Körperbau ein Dimorphismus, gleiches gilt für Jung- und Altvögel. Sie erreicht eine Körperlänge von rund 50 cm. Der Schnabel ist 59,2–63,8 mm lang. Die Neuhollandkrähe hat eine Flügellänge von 336–373 mm, ihr Schwanz misst 200–229 mm. Das Gewicht liegt zwischen 506 und 670 g.[3] Das vordere Halsgefieder ist bei ihnen leicht verlängert.
Das Gefieder der Neuhollandkrähe ist einheitlich schwarz. Das Gefieder an Kopf, Hals, Körperoberseite, Brust, Flanken sowie das Gefieder der Oberschwanzdecken glänzt schwarz. Der Schimmer reicht von einem metallischen Grün auf den Ohrendecken bis zu einem blauvioletten Schimmer auf den übrigen Körperteilen. Die Intensität des Schimmers hängt dabei stark vom Lichteinfall ab. Die Körperunterseite inklusive der Unterschwanzdecken ist mattschwarz.
Die Federn haben eine blassgraue bis mittelgraue Federbasis, schwarz sind die Federn lediglich ab der Mitte. Bei lebenden Vögeln ist die hellere Federbasis jedoch auch bei Starkwind nicht sichtbar.[4]
Der Schnabel schwarz, beim Oberschnabel ist das hintere Drittel inklusive der Nasenlöcher von langen Borstenfedern bedeckt. Unterhalb des Schnabels befindet sich ein nackter, unbefiederter Fleck, der V-förmig zum Kinn und an den Halsseiten verläuft. Bei adulten Vögeln ist die Iris weißlich mit einem hellblauen inneren Ring. Die Beine und die Füße sind schwarz.
Jungvögel sind geringfügig kleiner als die adulten Vögel. Der Schnabel ist bei ihnen noch kürzer. Das Gefieder glänzt noch nicht so stark wie bei den adulten. Der Schnabel ist bei ihnen noch dunkelgrau.
Der Ruf der Neuhollandkrähe besteht aus einem langgezogenen hohen, auf den Menschen klagend wirkenden Laut. Rufende Vögel sitzen gewöhnlich auf einem hohen Baum oder einem Strommasten.
In Australien kommen die Corvus-Arten Gesellschaftskrähe, Tasmankrähe, Salvadorikrähe und die Bennettkrähe vor, die bei Feldbeobachtungen schwierig voneinander zu unterscheiden sind. Verlängerte Halsfedern, wie sie für die Neuhollandkrähe typisch sind, kommen allerdings nur noch bei der Gesellschaftskrähe und der Tasmankrähe vor. Als sicherstes Unterscheidungsmerkmal gilt der Ruf.[4]
Die Neuhollandkrähe kommt in der östlichen Hälfte des australischen Kontinents sowie im Südwesten Australiens vor. Sie ist auf der Kap-York-Halbinsel sehr selten, nördlich des 16° südlicher Breite wurde sie bislang nur sehr selten beobachtet. In den Atherton Tablelands, die noch zu den Tropen zählen, ist sie nur in Küstennähe zu sehen. In den weiter nördlich liegenden australischen Bundesstaaten New South Wales und Victoria ist sie dagegen ein häufiger und weit verbreiteter Brutvogel. In South Australia fehlt sie im Westen und Nordwesten, besiedelt aber die Känguru-Insel, die nach Tasmanien und der Melville-Insel drittgrößte Insel Australiens, die 112 Kilometer südwestlich von Adelaide im Gulf Saint Vincent liegt. In West Australia kommt sie südlich der Nullarbor Plain vor und besiedelt vor allem den Süden und den Südwesten dieses Bundesstaates.[5] Im Northern Territory wird sie dagegen nur sehr selten beobachtet. Die meisten Beobachtungen stammen aus dem Osten und dem Süden dieses Bundesstaates. Auf Tasmanien dagegen fehlt die Neuhollandkrähe.[6]
Als Irrgast ist die Neuhollandkrähe gelegentlich auf Lord Howe Island zu beobachten. Beobachtungen von einem einzelnen Vogel dieser Art in Neuseeland gelten als zweifelhaft.[6]
Grundsätzlich gelten Neuhollandkrähen als sehr standorttreu. Ausgewachsene Brutpaare besetzen ganzjährig ein Revier, das etwa eine Größe von 120 Hektar hat. Außerhalb dieses Reviers sind sie nur sehr selten zu beobachten. Jungvögel bleiben im Revier der Elternvögel bis etwa zu einem Lebensalter von mindestens vier Monaten, typischerweise jedoch von fünf Monaten. Es wurde bislang nicht beobachtet, dass Jungvögel von den Elternvögel aus dem Revier vertrieben wurden. Es scheint dagegen eine starke Neigung von Jungvögeln zu geben, sich Trupps von Artgenossen anzuschließen.[7] Verlassen sie das Revier ihrer Elternvögel sind sie zunächst vor allem der Aggression von benachbarten Revierbesitzer ausgesetzt.
Die Trupps der Jungvögel, die bis zu 300 Vögel umfassen können. Diese durchstreifen sehr große Gebiete, die sie auf der Suche nach Nahrung über hunderte von Kilometer führen kann. Die Wanderbewegungen der Trupps sind vor allem vom Nahrungsangebot bestimmt. Sie können sich daher auch in einzelnen Regionen längere Zeit aufhalten. Dies kommt vor allem im australischen Herbst und Winter häufiger vor. Kleinere Trupps tendieren dagegen dazu, in einem Gebiet von circa 260 Quadratkilometer zu verbleiben.[7]
Neuhollandkrähen sind sehr anpassungsfähig und können eine große Bandbreite unterschiedlicher offener Lebensräume besetzen. In dichten Wäldern sind sie gewöhnlich nicht anzutreffen. Geeignete Lebensräume bieten ihnen ausreichend Wasser sowie entweder Bäume oder künstliche, menschengemachte Strukturen, die sie als Nist- und Ruheplatz nutzen können. Auf Grund dieser vergleichsweise geringen Anforderungen sind sie auch in Stadtgebieten häufiger zu beobachten.
Zu den typischen natürlichen Lebensräumen gehören vor allem Waldränder, Heiden, Buschland und Mangroven sowie Küstendünen.
Adulte Neuhollandkrähen sind überwiegend paarweise zu beobachten, gelegentlich auch in kleinen Familiengruppen, wenn die Jungvögel noch nicht das elterliche Revier verlassen haben. Sie sind vor allem an Aas gelegentlich auch in der Nähe von anderen Greifvogelarten wie Schwarzmilane, Keilschwanzadlern und Habichtfalken zu sehen. Der Flug kräftig und gradlinig, der Flügelschlag variiert jedoch abhängig von der vorherrschenden Windstärke. Auf dem Boden laufen sie leicht schwankend, der Körper schwingt mit jedem Schritt etwas zur Seite. Neuhollandkrähen, die sich auf dem Boden schneller fortbewegen, hüpfen sie auch.
Kleine Gruppen von Neuhollandkrähen hassen auf mittelgroße bis große Greifvogelarten wie beispielsweise den Keilschwanzadler, größere Milane oder Weihen, aber auch auf Reiher und Brillenpelikane. Sie fallen durch ihre Rufe und ihr auffälliges Verhalten schnell auf und sind vor allem in Agrarland gegenüber Menschen scheu. Im urbanen Lebensraum dagegen können sie sehr zutraulich werden.[4]
Neuhollandkrähen sind Allesfresser. Sie fressen überwiegend Insekten und andere Wirbellose. Sie decken ihren Nahrungsbedarf aber auch mit kleinen Wirbeltieren, dazu gehören kleine Singvögel, deren Eier und Nestlinge sowie Reptilien. Sie fressen regelmäßig Aas und sind deswegen häufig entlang von Straßenrändern zu beobachten, wo sie Tiere fressen, die im Straßenverkehr getötet wurden. Sie sind außerdem häufiger auf Müllhalden anzutreffen.[7] Ihre Nahrung finden sie überwiegend auf dem Boden.
Neuhollandkrähen horten gelegentlich Nahrung. Eine typische Situation, in der dieses vorkommt, ist beispielsweise an Aas, wenn das Tier größer ist als Neuhollandkrähen auf einmal fressen. Sie tragen dazu Teile etwa 100 Meter von dem Fundort weg und vergraben diese in der Erde. Bei einer beobachteten Neuhollandkrähe, die in einer Picknickzone mehr Futter fand, als sie auf einmal fressen konnte, wurde die Nahrungsbestandteile an verschiedenen Stellen vergraben und jede Stelle zunächst mit Erde, und dann mit Steinchen und Ästchen bedeckt.[8]
Neuhollandkrähen sind an keine spezifische Brutzeit gebunden, Nester und Gelege finden sich in jedem Kalendermonat. Sie schreiten jedoch vor allem im Zeitraum von August bis November zur Brut.[9] Das Nest wird gewöhnlich in hohen Baumkronen errichtet. Sie brüten aber auch auf Telefonmasten und ähnlichen menschengemachten Konstruktionen. Das Nest ist vergleichsweise groß und wird aus Ästen, Zweigen und Wurzeln gebaut. Die eigentliche Nistmulde wird mit Rinde, Gras und Fellresten oder Haaren ausgelegt. Beide Elternvögel sind am Bau des Nestes beteiligt. Der Nestbau dauert gewöhnlich zwei bis drei Wochen.[10] Sie benutzen ältere Nester auch für das nächste Gelege, in dem Fall ist das Nest gewöhnlich innerhalb von fünf Tagen repariert. Gelege können zwischen einem und sechs Eier umfassen. Typisch ist jedoch eine Gelegegröße von vier oder fünf Eiern.[10] Der Legeabstand beträgt ein bis zwei Tage. Es brütet alleine das Weibchen, das Männchen bringt in der Zeit Futter ans Nest. Das Brutzeit beträgt knapp 20 Tage. Das Weibchen hudert die Nestlinge während ihrer ersten zwei Lebenswochen. Auch während dieser Zeit bringt das Männchen Futter ans Nest. Ältere Nestlinge werden nur bei schlechtem Wetter vom Weibchen gehudert. Die Nestlingszeit beträgt knapp 44 Tage. Ältere Nestlinge, die bereits ausgeflogen sind, während jüngere Geschwister noch im Nest sitzen, kehren häufig zum Nest zurück, wenn diese gefüttert werden. Sie werden auch nach dem Verlassen des Nestes jedoch noch über Wochen von den Elternvögeln gefüttert. Etwa drei Monate, nachdem sie das Nest verlassen haben, sind sie selbständig.[11]
Die Mortalitätsrate ist am höchsten bei noch nicht geschlechtsreifen Vögeln. Von Neuhollandkrähen, die im Nest beringt wurden, überlebten knapp 65 Prozent nicht ihr erstes Lebensjahr. Sie sterben vor allem im australischen Winter, wenn sie ein Alter von fünf bis sechs Monaten erreicht haben. Sie haben sich zu dem Zeitpunkt von den Elternvögel gelöst und müssen selbständig ihren Nahrungsbedarf decken.[12] Die Sterblichkeit älterer Neuhollandkrähen liegt per annum bei etwas über 50 Prozent, d. h. jede zweite ausgewachsene Neuhollandkrähe erlebt auch noch ihr nächstes Lebensjahr. Der bisher älteste Vogel, dessen Alter anhand von Beringungsdaten ermittelt werden konnte, erreichte ein Alter von 12 Jahren und fünf Monaten.[7]
Die Neuhollandkrähe stand lange unter dem Verdacht, dass sie junge Lämmer tötet. Dieser Verdacht, der auch darauf beruhte, dass sie sich gelegentlich in größerer Zahl in der Nähe von Koppeln einfinden, in denen Schafe lammen, konnte jedoch weitgehend zerstreut werden: Sie fressen tote Lämmer, Fehlgeburten, töten allerdings gelegentlich kranke oder stark geschwächte Lämmer. Sie sind aber auf Grund dieses Verdachts früher von Schaffarmern sehr stark bejagt worden. Es wird mittlerweile verstärkt der Nutzen der Neuhollandkrähen in der Beseitigung der Kadaver gesehen.[13] Sie richten jedoch immer noch Schaden auf Farmen an, weil sie unter anderem Getreide fressen, das für die Schafe bereitgestellt wird. Sie brechen auch in die Laufställe mit Hühnern ein, um dort Eier zu fressen. Sie können außerdem in Obstplantagen Schäden anrichten.[12]
Der zu den Laubenvögeln gehörenden Tropfenlaubenvogel und Fleckenlaubenvogel ahmen die Rufe mehrerer Vogelarten nach, die sie als Fressfeinde kennen. Dazu zählen auch der Ruf der Neuhollandkrähe.[14][15]
Die Neuhollandkrähe (Corvus coronoides) ist ein Vogel aus der Gattung der Raben und Krähen (Corvus). Sie kommt ausschließlich in Australien und einigen der Küste vorgelagerten Inseln vor. Sie ist die in Australien am weitesten verbreitete und bekannteste Art der Rabenvögel. Neuhollandkrähen verwerten eine große Bandbreite Nahrungsquellen und sind sehr anpassungsfähig. Die IUCN stuft ihre Bestandssituation als ungefährdet (least concern) ein.
The Australian raven (Corvus coronoides) is a passerine bird in the genus Corvus native to much of southern and northeastern Australia. Measuring 46–53 centimetres (18–21 in) 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 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 (coronoides) highlighting its similarity with the carrion crow (C. corone). Two subspecies are recognized, 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, Perth and Brisbane. 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 other building.
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.[2] Its specific epithet coronoides "crow-shaped" is derived from the Greek corone/κορόνη "crow" and eidos/είδος "shape" or "form".[3] The two naturalists regarded the Australian raven as very similar in appearance to the carrion crow (C. corone) of Europe,[4] though they noted it was larger with a longer bill. They did not give it a common name.[2] The location where the type specimen was collected is not recorded, but thought to be in the Parramatta district.[5] Christian Ludwig Brehm described Corvus affinis in 1845,[6] later determined to be this species.[7] 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,[a] which predated Vigors and Horsfield's description.[10] 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".[5] 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).[11]
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.[12] Mathews had erected C. marianae in 1911 as the name after declaring Corvus australis Gould to be preoccupied;[13] French-American ornithologist Charles Vaurie acted as first reviser 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.[14] This has been followed by later authors.[15]
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. Stresemann 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.[5]
"Australian raven" has been designated the official name by the International Ornithologists' Union (IOC).[16] Alternative names sometimes seen include southern raven, southern crow and Kelly,[4] 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.[17] The term "crow" is colloquially applied to any or all species of Australian corvid.[5] The Australian raven was called wugan by the local Eora and Darug inhabitants of the Sydney Basin.[18]
Australian raven (eastern subspecies)
Australian raven (western subspecies)
Phylogenetic tree based on Jønsson et al. 2012[19]The Australian raven's closest relatives are the other two species of raven occurring in Australia: the little raven and forest raven. The Australian raven is also somewhat closely related to the Torresian and little crow, although not as closely related as it is to the other raven species. Initial single gene genetic analysis of the genus using mitochondrial DNA showed the three raven species to belong to one lineage and the two crows to another. The genetic separation between species is small and there was a suggestion the little raven may be nested within the Australian raven, though the authors conceded more genetic work was needed.[20] Subsequent multigene analysis using nuclear DNA by Jønsson and colleagues in 2012 showed the eastern and western subspecies of the Australian raven to form two clades, almost as genetically distinct as the forest and little raven are to each other. This led the authors to propose that the subspecies be recognised as separate species.[19]
Ian Rowley proposed that the common ancestor of the five species diverged into a tropical crow and temperate raven sometime after entering Australia from the north,[21] which molecular evidence indicates occurred in the early Pliocene epoch around 4 million years ago.[19] The raven diverged into the ancestor of the forest and little ravens in the east and Australian raven in the west,[21] this split occurring around 2 million years ago in the early Pleistocene.[19] As the climate became cooler and drier, the aridity of central Australia split them entirely. Furthermore, the eastern birds diverged into nomadic little ravens and, in forested refuges, forest ravens. As the climate eventually became warmer, the western birds spread eastwards and almost outcompeted forest ravens on mainland Australia. Rowley noted that the western subspecies of the Australian raven had features intermediate between the eastern subspecies of Australian and little ravens.[21]
Two subspecies are recognised:
Measuring 46–53 cm (18–21 in) in length with a 100 cm (39 in) wingspan and weighing around the 650 g (1.43 lb), the Australian raven is Australia's largest species of corvid.[4] The adult Australian raven is an all black-bird with a black beak, mouth and tongue and sturdy black or grey-black legs and feet.[24] The tibia is fully feathered and the tarsus is long, and the feet large and strong.[25] It has white irises.[24] The plumage is glossy with a blue-purple to a blue-green sheen, greenish over the ear coverts, depending on the light. The underparts are not glossy.[26] The Australian raven has throat feathers (hackles) that are lanceolate with rounded tips, while the other four species of Australian corvids have bifurcate tips, though this can be difficult to see in the field.[22] The hackles are also longer than those of the other four species; when they are raised (such as when the bird is calling), they give the bird an unusual bearded appearance. The upper third of the upper mandible, including the nares and nasal groove, is covered with bristles,[26] which can be up to 3 cm (1.2 in) long.[27] The heavy-set beak is tipped with a slight hook,[26] and is longer than the bird's head. The wings are long and broad, with the longest of its ten primary feathers (usually the seventh but occasionally the eighth) almost reaching the end of the tail when the bird is at rest. The tail is rounded or wedge-shaped.[25]
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The Australian raven can be distinguished from the two species of crow occurring in Australia by the grey base of the feathers, which is white in the latter species. The demarcation between pale and black regions on the feather is gradual in the ravens and sharply delineated in the crows. Feather bases are not normally visible when observing birds in the field, but can sometimes be seen on a windy day if the feathers are ruffled.[22] Unlike the other four species, the Australian raven has a bare patch of skin under and extending to beside, the bill. This can be hard to discern in the field. The three species of raven are more heavily set with a broader chest than the two crow species, with the forest raven the stockiest of all.[28] Relative size of species is only useful when two species can be seen side by side, as the overlap in size is large and the difference in size small.[29]
Juveniles resemble adults, but lack throat hackles,[27] and sometimes have a pink fleshy gape.[30] The bill is shorter and shallower;[26] its base can be pinkish and the tip can be light grey.[24] The plumage is more ruffled and softer in appearance, lacks the glossy highlights and often having a brown tinge.[26] The bare skin on the throat is pink in birds that have recently left the nest.[24] Eye colour varies with age, gradually lightening from juvenile to adult.[26] Nestlings up to four months old have blue-grey irises, juveniles aged from four to fifteen months have dark brown irises, and immature birds have hazel irises with an inner blue rim around each pupil until age two years and ten months.[5][b] Immature birds older than one year develop hackles,[25] while some pink remains in the gape until the bird is two or three years of age.[24]
The territorial call of the Australian raven is a slow, high ah-ah-aaaah (similar to the near-open front unrounded vowel (IPA:/æ/)) with the last note drawn out. It uses this call to communicate with other Australian ravens in the area.[31] When giving this call, the species has a horizontal posture, holding its head forward and body parallel to the ground, while perched on a prominent position. It ruffles its hackles and lowers its tail, and sometimes holds its beak open between calls. In contrast, the little raven and forest raven hold their bodies in an upright posture.[29] This call becomes louder if trespassers encroach upon the Australian raven's territory.[32] The five Australian species are very difficult to tell apart, with the call being the easiest way to do so,[4] although the drawing-out of the final note—long held to be solely recorded for the Australian raven—has been recorded for the other species and is hence not diagnostic.[29]
The volume, pitch, tempo and order of notes can be changed depending on the message the Australian raven intends to convey. There is a variety of contact calls: a pair often makes a low murmuring sound when preening each other while roosting, and members of a flock carry on with a quiet chattering while at rest. Birds make a call and answer sequence if temporarily out of sight of one another while foraging. Birds in flocks make a single high-pitched caa while flying over another territory as a transit call to signify they are just passing through. An Australian raven will give a longer caa with a downward inflection to signify its return to the nest to its mate.[32]
The Australian raven is common throughout eastern Australia,[30] and southern Western Australia (the populations being connected by a narrow strip across the Nullarbor Plain), but it is rarer and more scattered in the north, with isolated sightings in Cape York at Coen, Windmill Creek and the Mitchell River,[33] and becoming more common south of Rockhampton in central Queensland. It is found throughout New South Wales, though is uncommon in the northeast of the state. It is rare in the Australian Alps, being replaced there by the little raven. It occurs across Victoria and eastern South Australia, through the Eyre Peninsula and Nullarbor Plain into Western Australia, across the state north to the Wooramel River.[34] It is found on some offshore islands such as Rottnest Island[35] and Kangaroo Island.[34] It is a rare vagrant to Lord Howe Island.[34]
The Australian raven can be found in a wide range of natural and modified habitats. It requires available water and trees (or buildings) to roost in or perch on. Preferred habitats include eucalypt-dominated sclerophyll forest, and farmland adjacent to trees. It is also found in heath and mangroves. In areas where it occurs with the little raven, namely over much of central New South Wales, Victoria and into South Australia,[22] the Australian raven is restricted to more forested areas while the latter species prefers more open areas.[36] Similarly, in inland Australia it can share a range with the little crow, as the two do not appear to compete. However, the ranges of similar-sized forest raven and Torresian crow only narrowly overlap with the Australian raven as all three compete with each other. In central and western regions, Australian ravens and Torresian crows vie for the scattered uncommon trees and outcrops, and only one or the other are found there.[5] It co-occurs with the forest raven in northeastern New South Wales from Port Stephens northwards.[22] The Australian raven has adapted very well to human habitation in some cities and is the most common corvid in Canberra, Sydney and Perth; in Melbourne and Adelaide it is replaced by the little raven,[22] and by the Torresian crow in Brisbane.[37] Its large range, abundance and increasing population mean it is classified as Least Concern on the IUCN Red List.[1]
Difficulties in distinguishing Australian corvids has hampered understanding of seasonal movements. The Australian raven is thought to be largely sedentary, with most movement of over 16 km (9.9 mi) due to flocks of non-breeding subadult birds.[38] Juvenile birds leave their parents and join flocks when they are four or five months old. Smaller flocks of 8–30 birds stay within an area of around 260 square kilometres, while larger flocks of up to 300 birds may travel hundreds of kilometres seeking food.[39]
A single breeding pair and their brood can occupy a territory of up to around 120 hectares (300 acres) and remains there year-round, though groups of ravens may enter this area to forage.[38] Australian ravens will defend their territory by chasing, dive-bombing and occasionally striking the backs of birds of prey, foxes or even people.[40] They generally mate for life, though occasionally one male has been found to be mated with two females in adjacent territories.[32] If the female dies, the male Australian raven maintains the territory and finds another mate, while if the male bird is lost, the female abandons the territory.[41] No courtship behaviour has been observed, and species that mate for life often lack elaborate courting displays.[32] Once they begin breeding at three years of age, they live another four to five years on average. During this time they produce two surviving young each year on average.[41] The longest-lived Australian raven recorded is an adult (of at least 3 years of age) that was banded and recaptured alive 12 years and 5 months later.[39]
Australian ravens generally walk when moving around on the ground, though do hop when hurrying. They preen themselves frequently, particularly when roosting in the middle of the day. They also engage in allopreening, where birds will preen each other's head and neck. This takes place particularly in autumn, winter and spring, and is important in pair bonding.[32] Either member may initiate it, generally by landing near the other bird, shuffling next to its mate, then bending its head forward and presenting its nape.[42]
Australian ravens begin breeding once they are three years old.[41] Breeding season is from July to September,[43] with no substantial difference in timing across its range around the country despite it inhabiting a range of diverse climates and habitats across 19 degrees of latitude. Rowley has pointed out this is unusual for a bird species with a wide range and has postulated that breeding is initiated by day length. Rarely, breeding can take place in May, June or October.[44] Australian ravens generally nest in tall trees, never near to the ground as some species do.[33] The nest also functions as a lookout post and so tall or emergent trees are selected.[45] The ravens occasionally nest on buildings, telegraph poles,[33] or tall windmills which allow the species to occupy areas lacking in tall trees. Windmills may have assisted the spread of the species in North Queensland and the Northern Territory. The highest recorded corvid nest in Australia was found atop the AWA Tower in Sydney.[45]
Nests are generally large and untidy, consisting of a bowl or platform of sticks lined with grasses, barks, and feathers that can be up to 5 cm (2.0 in) thick.[46] As they are relatively heavy, they are built on larger forks in trees rather than out in the canopy. Building the nest is often time-consuming initially as the birds try (and often fail) to wedge sticks, which are 30–60 cm (12–24 in) long and 0.6–1.2 cm (1⁄4–1⁄2 in) thick, into the tree fork to make a platform. Thinner sticks and rootlets are used to make the bowl before the bowl is lined with feathers. Both birds build the nest, with the female taking over the lining of the nest while the male brings her material. New nests are built each year generally, as the re-use of old ones might spread disease or parasites—nests become caked with faeces as the nestlings grow and the parents cannot keep up with its removal. Furthermore, old nests often disintegrate within twelve months due to their exposed locations.[45] The female develops a brood patch—a patch of bare skin on the bird's underparts that reddens and becomes much more extensive from around three weeks before the first egg is laid. The skin itself is oedematous and wrinkled, and does not get re-feathered until December after the breeding season has finished.[44]
Their lofty locations makes monitoring of Australian raven nests difficult.[45] A clutch can comprise up to six eggs, though usually four or five are laid, with five being the most common number.[45] Measuring 45 by 30 mm (1+3⁄4 by 1+1⁄4 in), eggs are pale green or bluish-green and splotched with darker olive, brown and blackish markings.[43] Eggs are quite variable, and thus which Australian corvid laid them cannot be reliably identified.[45] Incubation of the eggs is done solely by the female over roughly 20 days. Incubation is intermittent initially, becoming constant by the time the third or fourth egg is laid.[46] Only one brood is raised per year, though a second clutch may be laid if the first clutch is lost early in the season. Late clutches have poor survival rates, possibly due to chicks getting dehydrated on hot days as the year progresses or being eaten by wedge-tailed eagles.[44] The chicks are altricial and nidicolous; that is, they are born helpless, naked and blind, and remain in the nest for an extended period.[46] They have pink skin until 5 days of age, when feathers under the skin turn it grey. They lose their egg tooth at the same time.[45] Their eyes begin opening at 5 to 6 days of age and are fully open by 11 to 12 days, by which time their feathers begin emerging. At 14 days, their primary feathers begin emerging, and they are fully feathered by 35–36 days old.[46] They leave the nest at 40–45 days of age, and stay with the parents for three to four months after that. They follow their parents and beg for food for the first month outside the nest but are feeding themselves by the third month. Young birds are often attacked when they enter neighbouring territories, and melees ensue as their parents try to defend them and herd them back.[45]
The Australian raven is omnivorous, though eats more meat than smaller corvids. Its diet in summer contains a high proportion of insects, while more plant items are eaten in autumn. Flesh makes up over half its diet in winter. Invertebrates commonly eaten include spiders, millipedes, centipedes (which ravens behead before eating), grasshoppers, cicadas and caterpillars (especially of the family Noctuidae), which are important in feeding nestlings. Australian ravens sometimes eat yabbies (Cherax destructor) from the edges of dams. Unusually for a ground-feeding omnivore, earthworms are rarely eaten. Australian ravens have been reported killing birds of such size as young galahs (Eolophus roseicapillus) and starlings (Sturnus vulgaris). Most mammals are eaten as carrion, as many species are too large for the raven to kill, though young rabbits are a frequent prey item.[47] Australian ravens drink water frequently, up to ten times a day in hot weather. Birds have been observed dunking pieces of meat in water before eating them,[32] as well as doing the same with hard biscuits to make them soggy and soft.[48]
Australian ravens are intelligent birds, and like many other corvids have innovative methods of seeking out food.[19] Foraging takes place in the early morning or late afternoon; birds rest in the hotter part of the day. Food is taken mainly from the ground, birds either finding objects while flying overhead or by walking along and looking.[32] However, they occasionally feed in trees—Australian ravens forage eucalypt foliage for Christmas beetles (Anoplognathus), and devote a substantial amount of time to look for nests and eggs to eat. They have also been known to take golf balls from fairways, possibly mistaking them for eggs.[47] Ravens use their bill rather than their feet to explore or turn items on the ground (rocks or sticks) over or hold or snatch food while flying. They have also been recorded using fence posts as anvils to bash snails against before eating them. Australian ravens most often eat food where they find it unless taking food back for nestlings. Occasionally they have been observed caching carrion or a killed animal in a hole nearby to store it. They can pack shredded meat in their mouth under their tongue.[32] Australian ravens have adapted well to eating food scraps in urban areas, such as school playgrounds, rubbish tips, bins outside supermarkets or restaurants, abattoirs, piggeries and farmyards.[33] In one isolated study, they were observed feeding on nectar from eucalypt flowers.[49] Australian ravens sometimes forage in mixed-species flocks with any of the other four species of Australian corvids. Sometimes they are aggressive with little ravens if both are at a food source and drive them off, though not if the smaller species greatly outnumber the larger.[50]
A circovirus—given the name raven circovirus or RaCV—was isolated from an Australian raven suffering from feather lesions in 2006. It has affinities with canary circovirus (CaCV) and pigeon circovirus (PiCV). Its clinical significance is unknown.[51] A species of Isospora—given the name of I. coronoideae was isolated from this species, its only known host.[52] Tick infestation is rare in the Australian raven, with Ixodes holocyclus and Amblyomma triguttatum recorded. Lice and hippoboscid flies have been recorded yet little-researched, and an infestation by the fly Passeromyia longicornis was recorded in one nest.[45]
The wedge-tailed eagle (Aquila audax) preys on adult, nestling, and fledgling Australian ravens, while the little eagle (Hieraaetus morphnoides) also takes nestlings, and powerful owl (Ninox strenua) has been recorded killing adults;[27] other birds of prey are seen as threats, yet there is no evidence they have successfully preyed on the ravens. The introduced red fox (Vulpes vulpes) competes with the Australian raven for carrion and can drive it off. It may also kill young birds that it catches on the ground.[45] The channel-billed cuckoo (Scythrops novaehollandiae) has been recorded as a brood parasite.[27]
Australian ravens sometimes die by being shot or poisoned—generally by farmers. Despite their fondness for roadkill, fewer ravens are hit by vehicles than Australian magpies. Research in the 1950s and 60s showed that 64% of Australian ravens perished in their first year of life. Immature birds are most at risk of dying.[39] The Australian raven is a peaceful bird, showing no aggression toward humans or other birds without reason. However, the Australian raven is frequently blamed for the loss of young lambs.[53] Scientific observation in the country's southeast showed that the killing of healthy lambs was rare, but that sick animals were predisposed to being attacked.[54] Australian ravens mostly eat faeces (often from the lamb's anus), afterbirth or stillborn lambs.[48][c] Newborn lamb faeces is nutritious, containing around 21–44% protein, 9–37% fat and 10–30% carbohydrate. It has the consistency of treacle and often sticks to the lamb's hindquarters or tail. The raven bites a sleeping lamb's tail, holding on and walking behind it when it wakes up. A healthy lamb would respond by running away or butting the bird, but a sick one might not respond and be attacked further as it alerts the bird that it is vulnerable. Wounded lambs can also succumb to Clostridium infection as these bacteria are present on raven bills.[54] Ravens bring some benefits to agricultural areas as they clean away carrion and eat insects that are potentially damaging to crops.[55] In areas of Western Australia, the species is classified as a Declared Pest of Agriculture under the provisions of the Agriculture and Related Resources Protection Act 1976, meaning that shooting on private land in rural areas is legal, although should be considered only after other options have been exhausted.[56]
In Australian Aboriginal mythology, Crow is a trickster, culture hero and ancestral being. In the Kulin nation in central Victoria he was known as Waa (also Wahn or Waang) and was regarded as one of two moiety ancestors, the other being the more sombre eaglehawk Bunjil. Legends relating to Crow have been observed in various Aboriginal language groups and cultures across Australia.[57]
To the Noongar people of southwestern Australia, the Australian raven was Waardar, "the Watcher" and was wily and unpredictable. Noongar people were socially divided into two moieties or kinships: waardarng-maat and marrnetj-maat, or members of the Australian raven and long-billed corella (Cacatua tenuirostris) respectively.[58]
The Australian raven (Corvus coronoides) is a passerine bird in the genus Corvus native to much of southern and northeastern Australia. Measuring 46–53 centimetres (18–21 in) 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 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 (coronoides) highlighting its similarity with the carrion crow (C. corone). Two subspecies are recognized, 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, Perth and Brisbane. 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 other building.
La Aŭstralia korako (Corvus coronoides) estas birdospecio membro de la familio de Korvedoj aŭ korvoj. Ĝi estas indiĝena de Aŭstralio kaj la plej granda membro tie de la genro Corvus kaj unu el la tri aŭstraliaj specioj komune konataj kiel korakoj. Ĝi estas iom pli svelta birdo ol la Komuna korako de la Norda Hemisfero, sed tamen ĝi estas ege simila. Ĝi havas tutnigran plumaron, bekon kaj krurojn kun blanka iriso, kiel la aliaj membroj de la genro Corvus en Aŭstralio kaj kelkaj specioj el la pli nordaj insuloj. Ĝi distingiĝas pro la elstaraj gorĝoplumoj kaj grizaj bazoj de siaj nigraj plumoj.
Ĝi estas ĉiomanĝanta, adaptiĝis bone al urba medio kaj estas komuna urbobirdo en Sidnejo.
La Aŭstralia korako estis unuafoje priskribita de Nicholas Aylward Vigors kaj Thomas Horsfield en 1827;[1] ties specia epiteto coronoides "kronforma" devenas el la greka corone/κορονη "krono" kaj eidos/ειδος "formo".[2] La du naturalistoj konsideris la Aŭstralian korakon kiel tre simila laŭ aspekto al la Nigra korniko (C. corone) de Eŭropo.[3]
Kvankam ĝi estas nomita korako, ties plej proksimaj parencoj estas la aliaj kvar specioj de aŭstraliaj korvedoj, kiuj inkludas la Toresan korakon, la Malgrandan korvon, la Tasmanian korakon kaj la Malgrandan korakon.[4]
Oni agnoskas du subspeciojn -C. c. coronoides, la nomiga subspecio, troviĝas tra plej parto de Orienta Aŭstralio, dum C. c. perplexus loĝas el la pinto de la Granda Aŭstralia Golfo en Suda Aŭstralio orienten al Okcidenta Aŭstralio kie ties nordaj limoj estas Shark Bay kaj la limo inter mulga kaj eŭkalipto. Intermezaj birdoj troveblas en la Duoninsulo Eyre, Gawler Ranges kaj proksimeco de la Lago Eyre en Suda Aŭstralio.[3]
Birdo 52 cm longa, la plenkreskulo de Aŭstralia korako estas tutnigra birdo kun ankaŭ nigraj piedoj kaj beko kaj blanka iriso ege kontrasta kun la resto de la korpo. La plumaro estas brila kun blupurpura al bluverda nuanco, verdeca ĉe orelkovriloj, depende de la lumo. La subaj partoj ne estas brilaj. La gorĝoplumoj estas pli longaj ol tiuj de aliaj samgenraj specioj.[5] Ĝi povas distingiĝi el la du specioj de korvo loĝantaj en Aŭstralio pro la griza bazo de la plumoj, kiuj estas blankaj en la aliaj specioj. Junuloj similas al plenkreskuloj, sed havas malhelajn okulojn, pli mallongajn gorĝoplumojn, kaj foje havas rozkoloran karnecan buŝon.[6]
La teritoria alvoko de la Aŭstralia korako estas malrapida, alttona ah-ah-ah-aaaah kun la lasta noto plilongigita.[4]
Tiu aŭstralazia korako estas komuna tra orienta, suda Aŭstralio kaj suda Okcidenta Aŭstralio (la populacioj estas konektitaj de mallarĝa zono tra Nularba Ebenaĵo) sed ili ne troviĝas en pli malproksima nordo. Ĝi adaptiĝis ege bone al homaj setlejoj en kelkaj urboj kaj estas komuna birdo en urba Sidnejo, kaj Insulo Rottnest.
En ruraj areoj sola reprodukta paro kaj ties idaro okupas teritorion de ĉirkaŭ 1 km², dum en urbaj areoj estas dekoble da birdoj ĉar multaj korakoj povas serĉi manĝon en la sama km².
Manĝo konsistas el kadavraĵoj, insektoj, semoj, fruktoj, etaj reptilioj, birdidojn kaj ovojn. La prefera proporcio estas 34% kadavraĵo, 42% senvertebruloj kaj 24% vegetala materialo. Manĝaĵojn oni prenas ĉefe de surgrunde sed ofte en arboj. Korakoj adaptiĝis bone manĝi rubaĵojn kaj aliajn maĝerojn en urbaj areoj, kiel en lernejaj kortoj. En unu izolita studo oni trovis ilin manĝantaj nektaron el floroj de eŭkalipto.[7]
Reprodukta sezono estas el julio al septembro.[8] Korakoj ĉiam nestumas en altaj arboj, neniam ĉegrunde kiel kelkaj specioj. Nestoj estas ĝenerale grandaj kaj malpuraj, konsiste el bulo aŭ platformo de bastonetoj kovritaj el herberoj, arboŝelo kaj plumoj.[9] Ovodemetado povas enhavi 3-6 ovojn, kvankam plej kutime 4 aŭ 5. Kaj ili estas 45x30 mm, palverdecaj aŭ bluverdecaj makulitaj el malhele olivverdaj, brunaj kaj nigrecaj markoj.[8] Kovado de la ovoj estas farita sole de la ino dum ĉirkaŭ 20 tagoj. Oni faras ununuran ovodemetadon ĉiujare. Elnestiĝo okazas post 45 tagoj kaj la idoj restas kun la gepatroj dum ĉirkaŭ kvar pliaj monatoj.
La Aŭstralia korako estas ofte kulpata je perdo de ŝafidoj.[10] Scienca observado en kamparo sudorienta montris, ke mortigo de sanaj ŝafoj estas rara, sed malsanaj animaloj foje estis atakitaj.[11]
La Aŭstralia korako (Corvus coronoides) estas birdospecio membro de la familio de Korvedoj aŭ korvoj. Ĝi estas indiĝena de Aŭstralio kaj la plej granda membro tie de la genro Corvus kaj unu el la tri aŭstraliaj specioj komune konataj kiel korakoj. Ĝi estas iom pli svelta birdo ol la Komuna korako de la Norda Hemisfero, sed tamen ĝi estas ege simila. Ĝi havas tutnigran plumaron, bekon kaj krurojn kun blanka iriso, kiel la aliaj membroj de la genro Corvus en Aŭstralio kaj kelkaj specioj el la pli nordaj insuloj. Ĝi distingiĝas pro la elstaraj gorĝoplumoj kaj grizaj bazoj de siaj nigraj plumoj.
Ĝi estas ĉiomanĝanta, adaptiĝis bone al urba medio kaj estas komuna urbobirdo en Sidnejo.
El cuervo australiano (Corvus coronoides)[1] es una especie de ave paseriforme de la familia Corvidae nativa de Australia. Es el más grande representante del género Corvus en Australia y una de las especies de córvidos más conocidas en Australia.
El cuervo australiano grande fue descrito por primera vez por Nicholas Aylward Vigors y Thomas Horsfield en 1827;[2] su nombre "crononoides", "its specific epithet coronoides "forma de cuervo" deriva del griego corone/κορονη, cuervo y eidos/ειδος, forma.[3]
Sus parientes más cercanos son otras cuatro especies de cuervo de Australia, las cuales son el Cuervo Torresiano y el Cuervo pequeño, así mismo como el cuervo del bosque y el Corvus mellori.
Con 52 centímetros, un cuervo australiano grande adulto es un ave negra con un iris blanco. Las plumas que están en el lomo son más grandes que las de cualquier otra especie de cuervo. Los jóvenes se parecen a los adultos, excepto en que tienen ojos oscuros.[4]
El cuervo australiano (Corvus coronoides) es una especie de ave paseriforme de la familia Corvidae nativa de Australia. Es el más grande representante del género Corvus en Australia y una de las especies de córvidos más conocidas en Australia.
Corvus coronoides Corvus generoko animalia da. Hegaztien barruko Corvidae familian sailkatua dago.
Australiankorppi (Corvus coronoides) on varisten heimoon kuuluva Australian kotoperäinen varpuslintu. Nimialalaji coronoides elää mantereen kaakkois- ja eteläosissa, ja alalaji perplexus Lounais-Australiassa. Nicholas Aylward Vigors ja Thomas Horsfield kuvailivat lajin holotyypin Uuden Etelä-Walesin Parramattasta vuonna 1827.[2]
Australiankorppi (Corvus coronoides) on varisten heimoon kuuluva Australian kotoperäinen varpuslintu. Nimialalaji coronoides elää mantereen kaakkois- ja eteläosissa, ja alalaji perplexus Lounais-Australiassa. Nicholas Aylward Vigors ja Thomas Horsfield kuvailivat lajin holotyypin Uuden Etelä-Walesin Parramattasta vuonna 1827.
Corvus coronoides
Le Corbeau d'Australie ou Corneille à gros bec (Corvus coronoides) (en anglais : Australian Raven) est une espèce australienne de passereaux de la famille des Corvidae. Il est un peu plus fin que le Grand Corbeau de l'hémisphère nord dont il est très proche.
Comme les autres corvidés australiens son iris est blanc mais il a en plus un anneau bleuté autour de la pupille. La totalité de son plumage est noir avec des reflets bleutés. Il a généralement, sous le bec, près du cou, une zone déplumée caractéristique de l'espèce. Son vol est puissant. Il a la même intelligence que tous les corvidés.
Avec ses 48 à 56 cm de long, il est un peu plus grand que le corbeau du désert dont il se distingue surtout par le cri plus aigu [1] et le dessin du bout des ailes.
Le corbeau d'Australie est très commun dans tout l'Est de l'Australie et le Sud de l'Australie-Occidentale, les deux parties étant reliées par une bande côtière : la Nullabor plain (voir carte). On ne le trouve pas dans le nord de l'Australie. Il s'est très bien adapté au voisinage de l'homme et c'est un oiseau très courant à Sydney et l'île Rottnest.
Il se nourrit de charognes, d'insectes, de graines, de fruits, de petits reptiles, d'oisillons et d'œufs. Il se nourrit surtout sur le sol accessoirement dans les arbres. En ville, il se nourrit des déchets et détritus.
Il niche au sommet des grands arbres. La femelle couve 5 à 7 œufs pendant 20 jours. Les petits peuvent voler au bout de 45 jours et restent avec leurs parents pendant les quatre mois suivants.
Corvus coronoides
Le Corbeau d'Australie ou Corneille à gros bec (Corvus coronoides) (en anglais : Australian Raven) est une espèce australienne de passereaux de la famille des Corvidae. Il est un peu plus fin que le Grand Corbeau de l'hémisphère nord dont il est très proche.
Il corvo imperiale australiano o semplicemente corvo australiano (Corvus coronoides Vigors & Horsfield, 1827) è un uccello passeriforme della famiglia Corvidae[2].
Il nome scientifico della specie, coronoides, deriva dal greco κορωνη (korōnē, col significato di "cornacchia"), con l'aggiunta del suffisso -οἶδες (-oìdes, "simile a"), anch'esso di origine greca, e col significato di "simile a una cornacchia", in riferimento all'aspetto di questi uccelli.
Misura 48–54 cm di lunghezza, per 500–820 g di peso[3]. I maschi sono leggermente più grossi e pesanti rispetto alle femmine.
Si tratta di uccelli dall'aspetto robusto e slanciato, muniti di testa squadrata con fronte sfuggente munita di becco conico e appuntito, robusto e lievemente arcuato verso il basso, collo robusto, lunghe ali digitate, lunghe zampe e coda piuttosto lunga e dall'estremità vagamente cuneiforme.
Nel complesso, il corvo imperiale australiano ricorda molto la cornacchia nera o il corvo imperiale vero e proprio, dai quali si distingue facilmente per gli occhi chiari: altre specie simpatriche con cui è possibile confonderlo vi sono il corvo imperiale minore (fino a tempi recenti classificato come sottospecie del corvo imperiale australiano, rispetto al quale è più piccolo e slanciato e dalle barbe golari bifide) ed il corvo di foresta (dalle dimensioni medie leggermente maggiori e dal becco più massiccio), ma da entrambi la specie si differenzia per la presenza di aree golari glabre.
Il piumaggio si presenta interamente di colore nero, dall'aspetto lucido e dalla consistenza vellutata: le penne presentano base grigia, visibile in condizioni di clima ventoso oppure quando l'animale arruffa le penne. Su testa, ali e coda sono presenti sfumature metalliche di colore blu-verdastro, visibili in particolar modo quando l'animale è esposto alla luce diretta.
La colorazione è identica nei due sessi.
Il becco e le zampe sono di colore nero: nera è anche l'area glabra al di sotto del becco, mentre gli occhi sono di colore bianco-azzurrino.
Il crvo imperiale australiano è un uccello dalle abitudini di vita essenzialmente diurne, che una volta adulto tende a vivere in coppie sedentarie che oppuna territori di circa 120 ettari[3], all'interno del quale possono essere tollerati all'infuori del periodo degli amori esemplari isolati o piccoli stormi di passaggio, costituiti dai giovani o da individui ancora non riproduttivi. Il territorio viene difeso dai due partner mediante richiami aggressivi o con attacchi, consistenti in picchiate, rincorse aeree e financo l'arpionamento del dorso con le zampe: a farne le spese sono principalmente i rapaci, ma in generale vengono aggrediti tutti gli animali considerati un pericolo, come volpi o anche esseri umani.
L'attività di questi uccelli è concentrata nelle prime ore del mattino e nel pomeriggio: essi passano la maggior parte della giornata alla ricerca di cibo al suolo, fermandosi generalmente per riposare durante le ore centrali della giornata, più calde, e ritirandosi nel tardo pomeriggio verso posatoi elevati per passare la notte. Durante le ore di riposo, non di rado i due partner passano molto tempo ad effettuare il grooming, pulendosi a vicenda il piumaggio di testa e dorso col becco.
I corvi imperiali australiani sono uccelli molto vocali: il richiamo di questi uccelli consiste in un gracchio miagolante e acuto, piuttosto lento e generalmente ripetuto tre volte, con tendenza ad abbassarsi nell'ultima sillaba. Durante le vocalizzazioni, questi corvi tengono il corpo in orizzontale (mentre le altre specie di corvo australiano tengono invece il corpo ben eretto in verticale), la coda abbassata e le barbe golari ben erette: a seconda della tonalità del richiamo è possibile intendere lo stato d'animo dell'animale che lo lancia, poiché esso diviene più forte ed acuto man mano che l'animale è più eccitato.
Oltre al richiamo classico, che serve per comunicare con tutti gli esemplari presenti nell'area circostante, le coppie o gli esemplari di uno stesso stormo interagiscono fra loro mediante bassi suoni chioccolanti, mentre questi ultimi comunicano alle prime l'intenzione di essere solamente di passaggio sul loro territorio mediante lunghi gracchi monosillabici.
Pur essendo un uccello virtualmente onnivoro e molto opportunista, che si ciba di qualsiasi corsa riesca a reperire durante la giornata, il corvo imperiale australiano presenta una componente carnivoro/insettivora della dieta nettamente predominante sulle altre.
Fra gli alimenti di origine animale consumati da questi uccelli vi sono insetti (cicale, cavallette, coleotteri come gli Anoplognathus, noctuidi) ed altri invertebrati (ragni, millepiedi, centopiedi, questi ultimi decapitati prima di essere consumati, lumache, ed anche gamberi di fiume australiani prelevati dalle acque basse, mentre i vermi vengono poco considerati per l'alimentazione), le loro larve, nonché piccoli vertebrati come uova e nidiacei ottenuti razziando i nidi, piccoli uccelli (fino alla taglia di un introdotto storno o di un cacatua rosa adulto) e mammiferi (topolini, coniglietti, piccoli marsupiali), nonché rettili di piccola taglia. Il corvo imperiale australiano è inoltre un grande consumatore di carogne, dalle quali ottiene cibo sia sotto forma di carne che di insetti saprofagi e delle loro larve. Fra i cibi di origine vegetale, consumati soprattutto durante l'autunno, vi sono frutta, bacche e granaglie, nonché, stando ad una singola osservazione, il nettare d'eucalipto[4].
I corvi imperiali australiani hanno imparato a sfruttare la crescente antropizzazione del loro areale a loro vantaggio, ottenendo grandi quantità di cibo sotto forma di scarti e rifiuti.
Il cibo viene cercato principalmente al suolo o (nel caso dei nidi) fra i rami degli alberi, e consumato al momento, a meno che la coppia non sia in riproduzione ed intenda portarlo alla prole, caso in cui esso viene conservato sotto la lingua durante il trasporto: sebbene raramente, anche i corvi imperiali australiani sono stati osservati nascondere il cibo in eccesso in buchi scavati nel terreno col becco. Per cercare fra i detriti ed il fogliame, nonché per trasportare il cibo, viene utilizzato sempre il becco, piuttosto che le zampe: il cibo particolarmente coriaceo, come ad esempio la frutta a guscio o le lumache, viene poggiato su un supporto duro (una roccia appiattita o un paletto di una staccionata) e frantumato a colpi di becco. Talvolta, i corvi imperiali australiani rubano le palline da golf dai campi, verosimilmente scambiandole per uova incustodite.
Questi corvi sono dei grandi bevitori: durante i periodi caldi, essi possono recarsi a bere anche dieci volte al giorno. L'acqua viene utilizzata anche per lavare il cibo, così come per tenere in ammollo i biscotti prima di consumarli.
La stagione riproduttiva va dalla fine di luglio alla fine di ottobre[3], con una media di due covate l'anno portate avanti: si tratta di uccelli monogami, sebbene in un caso sia stato osservato un maschio bigamo con due compagne in due territori adiacenti. Le coppie durano per la vita: se la femmina muore, il maschio rimane nello stesso territorio cercando di trovare una nuova compagna, mentre viceversa la femmina comincia a vagare fra i territori circostanti alla ricerca di un partner[5].
La specie nidifica in posti sopraelevati, come alberi isolati o più alti rispetto a quelli circostanti, lampioni o edifici (fra cui i mulini a vento, che verosimilmente hanno permesso a questi uccelli nel corso del XIX secolo di espandere il proprio areale in direttrice nord-ovest[6]).
Il nido, voluminoso e grossolano, ha la forma di una coppa con piattaforma circostante e viene edificato da ambedue i sessi (col maschio che fornisce il materiale e la femmina che lo intreccia) sulla biforcazione del tronco appena sotto la canopia, intrecciando rametti e fibre vegetali e foderando l'interno con pezzetti di corteccia, pelame e piumino.
All'interno del nido, la femmina depone 3-6 uova di colore verde-azzurrino con screziature di color bruno-olivastro, che provvede a covare da sola (imbeccata e protetta dal maschio, che rimane di guardia nei pressi del nido durante tutto il processo d'incubazione) per circa 20 giorni, al termine dei quali schiudon pulli ciechi ed implumi.
I nidiacei, rosa alla nascita, divengono grigi verso il quinto giorno d'età, a causa della formazione delle penne sotto la pelle: a quest'età, essi cominciano generalmente ad aprire gli occhi, processo che si ultima tuttavia a 11-12 giorni di vita, quando anche le penne divengono visibili. I piccoli sono del tutto piumati a 35-36 giorni dalla schiusa: essi cominciano a tentare l'involo a 40-45 giorni di vita, continuando tuttavia a rimanere coi genitori ancora per 3-4 mesi prima di rendersene indipendenti. I giovani sono piuttosto goffi e non in grado di reperire tutto il cibo del quale hanno bisogno prima dei tre mesi di vita: non di rado, essi sconfinano nei territori circostanti, venendo aggrediti dalle altre coppie in nidificazione e generando combattimenti fra queste ed i propri genitori, frattanto accorsi per recuperare la prole.
I giovani presentano occhi di colore blu-grigiastro, che diviene in seguito bruno fino ai quindici mesi, quando comincia a svilupparsi attorno alla pupilla la colorazione bianco-azzurrina che sostituisce il bruno entro i 2-3 anni di vita dell'animale. Una volta allontanatisi dai genitori, i giovani si riuniscono in piccoli stormi di 8-30 individui, che occupano piccoli territori di 260 km2: a loro volta, questi gruppi si fondono fra loro a formare stormi di maggiore consistenza, nei quali confluiscono anche gli esemplari adulti non accoppiati, i quali mostrano nomadismo e percorrono centinaia di chilometri alla ricerca di cibo[5].
La maturità sessuale viene raggiunta attorno al secondo anno d'età, sebbene raramente un corvo imperiale australiano riesca a trovare un partner prima dei tre anni: la speranza di vita in natura è di circa 8 anni, col record appartenente ad un individuo inanellato da adulto (quindi ad oltre tre anni d'età) e ricatturato vivo 12 anni e 5 mesi dopo.
La specie subisce parassitismo di cova da parte del cuculo becco scanalato.
Il corvo imperiale australiano, come intuibile dal nome comune, è endemico dell'Australia, della quale popola l'intero settore centro-orientale, la fascia costiera meridionale e quella occidentale, a nord grossomodo fino alla Shark Bay. La specie manca dal Top End e dalla costa settentrionale e nord-occidentale dell'isola, nonché dalla vasta area desertica centro-occidentale e dalla Tasmania: essa è inoltre rara sulle Alpi australiane, a Melbourne e Adelaide (dove viene sostituita dall'affine e fino a non molto tempo fa conspecifico corvo imperiale minore), a Brisbane (dove viene rimpiazzato dal corvo di Torres), nel Gippsland e in alcune aree del Nuovo Galles del Sud nord-orientale (dove viene sostituita dal corvo di foresta), nella penisola di Capo York e sulla costa del golfo di Carpentaria, risultando comune solo a partire grossomodo a sud di Rockhampton)[7]. Popolazioni sono presenti anche a Rottnest Island e Kangaroo Island[8].
Il corvo imperiale australiano è una specie generalmente residente, allontanandosi raramente di più di 5 km dal proprio territorio di appartenenza: tuttavia, specialmente i giovani e gli esemplari non riproduttivi presentano un certo potenziale di dispersione, con esemplari accidentali segnalati sull'isola di Lord Howe[5].
Si tratta di uccelli molto versatili, che colonizzano un po' tutti gli habitat presenti nel loro areale, dai pascoli alpini fino a 2000 m di quota[3] alle aree sabbiose costiere attraverso la macchia mediterranea a sclerofillo, i mangrovieti e le aree coltivate, evitando però quelle troppo densamente alberate: in generale, qualsiasi posto dove siano presenti aree aperte per reperire il cibo ed uno o più punti sopraelevati dove passare la notte e nidificare è sufficiente ad ospitare una popolazione stabile di corvi imperiali australiani.
Se ne riconoscono due sottospecie[2]:
Le due sottospecie appaiono piuttosto distanti fra loro, e potrebbero rappresentare due specie a sé stanti[3]: la presunta sottospecie difficilis viene considerata il risultato dell'analisi di giovani soggetti aberranti, e pertanto non ritenuta valida[3], mentre in passato veniva considerata una sottospecie di questi uccelli anche il corvo imperiale minore.
Verosimilmente, l'ultimo antenato comune dei corvi australiani, giunto da nord-ovest, cominciò a divergere, prima col distacco dei piccoli corvo minore e cornacchia delle Bismarck ed in seguito, con l'abbassamento della temperatura e la desertificazione del centro dell'isola-continente, in quelli che poi diverranno il corvo imperiale australiano nella porzione occidentale, il corvo imperiale minore nelle aree secche della porzione orientale ed il corvo di foresta nelle porzioni boschive, con la prima che ha poi esteso il proprio areale verso est a spese dell'ultima (che infatti in Australia continentale occupa unicamente le aree di foresta fitta che il corvo imperiale australiano evita, mentre in Tasmania è presente un po' in tutti gli ambienti)[9].
Il corvo imperiale australiano o semplicemente corvo australiano (Corvus coronoides Vigors & Horsfield, 1827) è un uccello passeriforme della famiglia Corvidae.
De Australische raaf (Corvus coronoides) behoort tot de familie van de kraaiachtigen.
Deze soort is endemisch in Australië en telt 2 ondersoorten:
De Australische raaf (Corvus coronoides) behoort tot de familie van de kraaiachtigen.
Multimedia w Wikimedia Commons Kruk australijski (Corvus coronoides) – gatunek dużego ptaka z rodziny krukowatych (Corvidae).
To największy przedstawiciel rodzaju Corvus w Australii i zarazem jeden z 3 gatunków, który nazywany jest powszechnie na tamtym kontynencie krukiem. Jest bardziej smukły niż kruk Corvus corax żyjący na północnej półkuli, choć oba są bardzo podobne. Ma w całości czarne upierzenie, dziób i nogi z białą tęczówką, podobnie jak inne australijskie ptaki z rodzaju Corvus (i niektóre inne zasiedlające wyspy leżąca bardziej na północ). Jest wszystkożerny i dobrze przystosował się do życia w mieście – w Sydney i Canberze to popularny ptak.
Kruk australijski został po raz pierwszy opisany przez Nicholasa Aylwarda Vigorsa i Thomasa Horsfielda w 1827 roku[3]. Nazwa naukowa coronoides oznacza "krukokształtny", z języka greckiego corone/κορονη "kruk" i eidos/ειδος "kształt" lub "forma"[4]. Dwóch badaczy historii naturalnej dostrzegło duże podobieństwo kruka australijskiego do europejskiego czarnowrona C. corone)[5].
Chociaż jest to kruk, najbliższe pokrewieństwo dzieli z innymi czterema gatunkami australijskich krukowatych. Są to: wrona papuaska, wrona mała, kruk tasmański i kruk mały.
Czasem używa się innych nazw, np. "kruk południowy", "wrona południowa" lub "Kelly". Przez rdzenną aborygeńską ludność Eora i Darug, żyjącą w okolicy Sydney, zwany jest "wuganem"[6].
Wyróżnia się dwa podgatunki[7][8]:
Mierzy 46-53 cm długości i ma 100 cm rozpiętości skrzydeł. Waży około 650 g. Dorosły kruk australijski jest w całości czarny, takiej barwy są też nogi i dziób. Tęczówka jest biała. Ubarwienie ma niebiesko-fioletowy lub niebiesko-zielony połysk, pióra na pokrywach usznych mienią się na zielono (kolor zależy od intensywności światła). Spodnia część ciała nie ma połyskliwych piór. Upierzenie na gardle jest dłuższe niż u innych gatunków[9]. Kruka australijskiego można rozróżnić od innych podobnych australijskich gatunków po szarej podstawie piór (u innych ptaków jest biała). Osobniki młodociane przypominają z wyglądu dorosłe, ale mają ciemne oczy, krótsze pióra na gardle, a czasem widać u nich różowe, połyskujące tłusto wnętrze dzioba[10].
Terytorialny okrzyk kruka australijskiego to przeciągliwe, wysokie ah-ah-aaaah z ostatnim wydłużonym tonem. Wykorzystuje ten odgłos do komunikacji z innymi osobnikami, które znajdują się w pobliżu[11] Identyfikacja kruka po głosie jest najprostszym sposobem rozróżnienia go od pięciu innych podobnych do siebie z wyglądu gatunków.
Kruk australijski jest szeroko rozpowszechniony w południowo-wschodniej Australii[12] i południowej części Zachodniej Australii (populacje są połączone wąskim pasem przebiegającym przez nizinny Nullarbor Plain), ale nie spotyka się go w północnej części kontynentu.
Ptak bardzo dobrze zaadaptował się do ludzkich siedlisk w niektórych miastach – powszechnie występuje w Melbourne, Sydney i na Wyspie Rottnest.
Na obszarach wiejskich pojedyncze pary i ich lęgi zajmują około 1 km² terytorium, podczas gdy na terenach zurbanizowanych występują 10 razy liczniej (wynika to z łatwiej dostępnego tam pokarmu).
W diecie znajduje się padlina, owady, nasiona, owoce, małe gady, pisklęta i jaja. Udział poszczególnych elementów pokarmu to 34% padliny, 42% bezkręgowców i 24% składników roślinnych. Jedzenie znajduje głównie na ziemi, ale czasami karmi się też na drzewach. Kruki australijskie dobrze przystosowały się do jedzenia wyrzuconych resztek i odpadków w miejskich warunkach, np. na szkolnych placach zabaw. Doniesiono o przypadku, gdzie kruk wyjada nektar z kwiatów eukaliptusa[13]
Okres reprodukcji przypada na lipiec – sierpień. Kruki zawsze gnieżdżą się na wysokich drzewach, nigdy nie blisko gruntu, co zdarza się u innych gatunków. Gniazda są przeważnie duże i chaotycznie zbudowane. Gałęzie, które je budują, są ułożone w kształcie miski lub stanowią platformę wypełnioną trawą, korą i piórami[14]. W lęgu znajduje się 3-6 jaj, choć samica składa zwykle 4-5. Mierzą 45 na 30 mm. Jaja są bladozielono lub niebieskawo-zielono plamkowane z ciemniejszymi oliwkowymi, brązowymi i czarnymi kropkami[15]. Samica sama wysiaduje jaja przez około 20 dni. W ciągu roku jest wyprowadzony jedynie jeden lęg. Pisklęta pierzą się w ciągu 45 dni i pozostają z rodzicami przez kolejne 4 miesiące.
Kruki australijskie są często obwiniane o straty czynione w hodowlach młodych jagniąt[16]. Obserwacje ornitologiczne poczynione na obszarach wiejskich na południowym wschodzie wykazały, że kruki rzadko zabijają zdrowe jagnięta, a celem ich ataków są głównie zwierzęta chore[17].
Kruk australijski (Corvus coronoides) – gatunek dużego ptaka z rodziny krukowatych (Corvidae).
To największy przedstawiciel rodzaju Corvus w Australii i zarazem jeden z 3 gatunków, który nazywany jest powszechnie na tamtym kontynencie krukiem. Jest bardziej smukły niż kruk Corvus corax żyjący na północnej półkuli, choć oba są bardzo podobne. Ma w całości czarne upierzenie, dziób i nogi z białą tęczówką, podobnie jak inne australijskie ptaki z rodzaju Corvus (i niektóre inne zasiedlające wyspy leżąca bardziej na północ). Jest wszystkożerny i dobrze przystosował się do życia w mieście – w Sydney i Canberze to popularny ptak.
O corvo-australiano (Corvus coronoides) é uma ave da família Corvidae (corvos).[1]
Com a sua zona de distribuição limitada à Austrália, pode ser encontrada no sudoeste e em toda a parte oriental deste país.
Normalmente habitam em zonas abertas, pouco arborizadas, como são as vastas zonas de pastagens australianas. Podem ainda ser encontrado em florestas pouco densas de eucaliptos.
Estas aves vivem em acasalamento permanente, necessitando de um território bastante grande para se reproduzirem. A sua época de reproducção vai de Julho a Setembro. O ninho, normalmente situa-se em árvores bastante altas, com mais de 10 metros de altura e é construído pelos dois membros do casal. Trata-se de um ninho bastante grande em forma de cesto, construído cuidadosamente com ramos, ervas, casca de árvores e revestido por dentro de penas.
A postura é de 5 a 7 ovos sendo a incubação assegurada exclusivamente pela fêmea durante os 20 dias que dura o período de choco.
Os filhotes são alimentados por ambos os pais e abandonam o ninho com aproximadamente 45 dias de idade, mantendo-se junto da família durante os 4 meses seguintes. Depois de se separarem dos progenitores vagueiam, até que atingem a maturidade reprodutiva, por volta dos 3 anos de idade, altura em que acasalam e se fixam num território para toda a vida.
Com uma actividade necrófaga bastante importante, tem como componente principal da sua alimentação a carne proveniente de cadáveres de outros animais, especialmente ovelhas e cangurus. Fazem ainda parte da sua alimentação insectos, pequenos répteis, vermes e outros invertebrados, frutas, cereais, bagas e resto de comida humana, em zonas urbanas. Pode ainda atacar ninhos para comer os ovos ou as crias.
Procuram o alimento geralmente no chão, sendo quase sempre as primeiras aves a chegar junto dos cadáveres.
O corvo-australiano (Corvus coronoides) é uma ave da família Corvidae (corvos).
Australisk korp[2] (Corvus coronoides) är en fågel i familjen kråkfåglar inom ordningen tättingar.[3] IUCN kategoriserar arten som livskraftig.[1]
Australisk korp delas in i två underarter:[3]
Wikimedia Commons har media som rör australisk korp.
Wikispecies har information om Corvus coronoides.
Australisk korp (Corvus coronoides) är en fågel i familjen kråkfåglar inom ordningen tättingar. IUCN kategoriserar arten som livskraftig.
Australisk korp delas in i två underarter:
Corvus coronoides coronoides – förekommer i östra Australien (Carpentariaviken till centrala Australien och södra Victoria) Corvus coronoides perplexus – förekommer i sydvästra Western Australia till långt i sydväst i South AustraliaЦе великий, блискуче-чорний птах. Важить близько 555 гр, і, як правило, розміром близько 52 см. Молодші птахи мають темніші очі, ніж старі птахи[1].
Quạ Úc, tên khoa học Corvus coronoides, là một loài chim trong họ Corvidae.[2] Đây là loài bản địa từ phần lớn miền nam và đông bắc Australia. Với chiều dài 46-53 cm, loài này có bộ lông, mỏ và miệng toàn màu đen, cũng như chân và bàn chân màu đen xám mạnh mẽ.
Nicholas Aylward Vigors và Thomas Horsfield đã mô tả quạ Úc vào năm 1827, tên loài của nó (coronoides) nêu bật sự tương đồng của loài này với loài quạ đen (C. corone). Hai phân loài được công nhận, khác nhau đôi chút về các cuộc gọi và khá khác nhau về mặt di truyền. Môi trường sống ưa thích là rừng cây mở và các khu vực chuyển tiếp. Loài quạ này thích nghi tốt với môi trường đô thị và là một loài chim thành phố phổ biến ở Sydney, Canberra và Perth. Một nguồn cung cấp ăn tạp và cơ hội, chúng ăn nhiều loại thực vật và động vật, cũng như chất thải thực phẩm từ các khu vực đô thị. Ở miền đông Australia, phạm vi của nó có mối tương quan mạnh mẽ với sự hiện diện của cừu và nó đã bị đổ lỗi cho việc giết cừu. Tuy nhiên, điều này rất hiếm, và loài quạ này thường nhặt rác để sinh con và động vật chết non cũng như phân cừu mới sinh. Quạ Úc có tính lãnh thổ, với các cặp thường gắn kết suốt đời. Mùa sinh sản diễn ra giữa tháng Bảy và tháng 9. Chiều dài thân 46 chiều dài 53 cm với sải cánh 100 cm và nặng khoảng 650 g,[3] quạ Úc trưởng thành có mỏ màu đen, miệng và lưỡi và chân và bàn chân đen hoặc xám đen cứng cáp.[4] đùi có lông hoàn toàn và bàn chân dài, và bàn chân to và khỏe. [5] Chúng có móng mắt. [4] Bộ lông có độ bóng với màu xanh lam tím đến xanh lam, xanh lục trên các miếng che tai, tùy thuộc vào ánh sáng. Mặt dưới không bóng.
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rowley 1970
Quạ Úc, tên khoa học Corvus coronoides, là một loài chim trong họ Corvidae. Đây là loài bản địa từ phần lớn miền nam và đông bắc Australia. Với chiều dài 46-53 cm, loài này có bộ lông, mỏ và miệng toàn màu đen, cũng như chân và bàn chân màu đen xám mạnh mẽ.
Nicholas Aylward Vigors và Thomas Horsfield đã mô tả quạ Úc vào năm 1827, tên loài của nó (coronoides) nêu bật sự tương đồng của loài này với loài quạ đen (C. corone). Hai phân loài được công nhận, khác nhau đôi chút về các cuộc gọi và khá khác nhau về mặt di truyền. Môi trường sống ưa thích là rừng cây mở và các khu vực chuyển tiếp. Loài quạ này thích nghi tốt với môi trường đô thị và là một loài chim thành phố phổ biến ở Sydney, Canberra và Perth. Một nguồn cung cấp ăn tạp và cơ hội, chúng ăn nhiều loại thực vật và động vật, cũng như chất thải thực phẩm từ các khu vực đô thị. Ở miền đông Australia, phạm vi của nó có mối tương quan mạnh mẽ với sự hiện diện của cừu và nó đã bị đổ lỗi cho việc giết cừu. Tuy nhiên, điều này rất hiếm, và loài quạ này thường nhặt rác để sinh con và động vật chết non cũng như phân cừu mới sinh. Quạ Úc có tính lãnh thổ, với các cặp thường gắn kết suốt đời. Mùa sinh sản diễn ra giữa tháng Bảy và tháng 9. Chiều dài thân 46 chiều dài 53 cm với sải cánh 100 cm và nặng khoảng 650 g, quạ Úc trưởng thành có mỏ màu đen, miệng và lưỡi và chân và bàn chân đen hoặc xám đen cứng cáp. đùi có lông hoàn toàn và bàn chân dài, và bàn chân to và khỏe. Chúng có móng mắt. Bộ lông có độ bóng với màu xanh lam tím đến xanh lam, xanh lục trên các miếng che tai, tùy thuộc vào ánh sáng. Mặt dưới không bóng.
澳洲渡鸦（学名：Corvus coronoides）是鸦科鸦属的一种，为澳大利亚的特有种。该物种的保护状况被评为无危。[1]
澳洲渡鸦的平均体重约为635.0克。栖息地包括多岩石的海岸、牧草地、潮池、城市、沙滩、沙洲、沙嘴、耕地、海崖和多岩石的离岸岛屿、干燥的稀树草原、乡村花园和多卵石或砾石的海岸。
澳洲渡鸦（学名：Corvus coronoides）是鸦科鸦属的一种，为澳大利亚的特有种。该物种的保护状况被评为无危。
澳洲渡鸦的平均体重约为635.0克。栖息地包括多岩石的海岸、牧草地、潮池、城市、沙滩、沙洲、沙嘴、耕地、海崖和多岩石的离岸岛屿、干燥的稀树草原、乡村花园和多卵石或砾石的海岸。
