Forest Raven
| Forest Raven | |
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| Conservation status | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Passeriformes |
| Family: | Corvidae |
| Genus: | Corvus |
| Species: | C. tasmanicus |
| Binomial name | |
| Corvus tasmanicus Mathews, 1912 |
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| Distribution map | |
The Forest Raven (Corvus tasmanicus) is the largest species of the crow genus in Australia. It is native to south-eastern Australia and Tasmania.
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Description [edit]
The Forest Raven is the largest of the Australian corvid species and is the sole representative of the genus Corvus in Tasmania. It is 50–53 cm in length with a wingspan of around 102 cm and weight of approximately 650g.[2] The plumage is a glossy black, with a blue or green sheen visible on upper plumage, there is no seasonal variation in plumage. The iris is white. It has a proportionately larger bill and shorter tail than the other mainland corvid species. Sexes have identical plumage, however the male is generally larger, although there is considerable overlap in size between individuals.
Juveniles are smaller than adults, with a shorter slightly and greyer bill, and softer plumage that has less sheen. Adult plumage is attained at three years of age, with younger immature birds lacking adult hackles, and retaining the brown coloured irises of juvenile birds.[2]
Vocalization [edit]
The call is considered the most reliable means of identification in areas where its range overlaps with other corvid species, and is a deep "korr-korr-korr-korr" with a similarly drawn out last note to the Australian Raven.
Subspecies [edit]
An outlying population exists in a small area in the tablelands of north-eastern New South Wales. The suggestion that this form be given specific rank and be known as the Relict Raven (Corvus boreus) appears not to have gathered favour, and the Relict Raven remains classified as a subspecies, C. tasmanicus boreus.
A scientific study of the Forest Raven (C. tasmanicus) and the Little Raven (C. mellori) is being undertaken by the Victorian Ornithological Research Group in Victoria.
Distribution and habitat [edit]
The Forest Raven inhabits a wide range of habitat within Tasmania such as woods, open interrupted forest, mountains, coastal areas, farmland and town and city fringes. It is also found in southern Victoria from Gippsland west through Wilson's Promontory and the Otway Ranges. Further west, it occurs patchily in south-east South Australia.
In its present stronghold — the state of Tasmania — the Forest Raven is one of only three native birds that have no legal protection outside national parks and other reserves. The other two unprotected species are the Great Cormorant and the Little Pied Cormorant. All other native Tasmanian birds are listed as protected under the state's Nature Conservation Act 2002.
Behaviour [edit]
Diet [edit]
A typical omnivore taking a very wide range of foods such as insects, carrion, fruit, grain and earthworms. It has been known to kill and eat birds as large as the Silver Gull (Larus novaehollandiae) using some degree of cunning by pretending to forage near enough to get close for the kill.
Nesting [edit]
The nest is constructed from sticks and twigs, and lined with available materials such as leaves, wool, grass, bark or feathers. Nests are generally constructed in a similar manner to the Australian Raven, high in a tall tree, however nests have been constructed on the ground in locations such as Tasmania's offshore islands where trees are not available.[2]
Photo Image Links [edit]
References [edit]
- ^ BirdLife International (2012). "Corvus tasmanicus". IUCN Red List of Threatened Species. Version 2012.1. International Union for Conservation of Nature. Retrieved 16 July 2012.
- ^ a b c Higgins, P.J., J.M. Peter & S.J. Cowling (eds) 2006. Handbook of Australian, New Zealand and Antarctic Birds. Volume 7: Boatbill to Starlings. Oxford University Press, Melbourne. ISBN 0-19-553996-6 (volume 7 set)
The Field Guide to the Birds of Australia. Pizzey G and Knight F.
