Slender-billed Vulture
Gyps tenuirostris
Gaunt scavenger with long, broad squarish-tipped wings and a long hairless neck. Dark overall with pale underparts. Very similar to Indian Vulture; note darker neck without white down covering, overall darker body coloration, and less white on the bill. Lacks white rump and contrasting underwing of White-rumped Vulture. Inhabits plains, grasslands, and open forests from lowlands up into the foothills. Congregates in large flocks at carcasses, where it hisses and cackles loudly. Once common; now fairly rare.
识别特征
At 80 to 95 cm (31 to 37 in), in length, this mid-sized vulture is about the same size as its sister species, the Indian vulture. This vulture is mostly grey with a pale rump and grey undertail coverts. The thighs have whitish down. The neck is long, bare, skinny and black. The black head is angular and narrow with the dark bill appearing narrow midway. The ear opening is prominent and exposed.
分类信息
- 学名
- Gyps tenuirostris
- 命名信息
- Gray, GR, 1844
- 目
- Accipitriformes
- 科
- Accipitridae
- 属
- Gyps
分布与栖息地
The slender-billed vulture is found in India from the Gangetic plain north, west to Himachal Pradesh, south potentially as far as northern Odisha, and east through Assam. It is also found in north and central Bangladesh, southern Nepal, Burma and Cambodia.
- 迁徙
- Resident species
保护状况
This species has suffered a marked decline in its numbers in recent years. The population of this species and the Indian vulture declined by 97% overall and in India annual decline rates for both species averaged over 16% between 2000–2007. Wild populations remain from northern and eastern India through southern Nepal and Bangladesh, with a small population in Burma. The only breeding colony in Southeast Asia is in the Steung Treng province of Cambodia. This colony is thought to number about 50–100 birds. The survival of the vultures in Cambodia may have been partly because diclofenac, which is poisonous to vultures, is not available there. The Royal Society for the Protection of Birds (RSPB) has placed the approximate number of slender-billed vultures living beyond confines at about 1,000 in 2009 and predictions estimate total extinction within the next decade amongst the wild population.<p>The slender-billed vulture is a protected species listed on the appendix II list of CITES, because its numbers have declined rapidly. Its decline is largely due to the use of the non-steroidal anti-inflammatory drug (NSAID) diclofenac in working farm animals. Diclofenac is poisonous to vultures, causing kidney failure, and is being replaced by meloxicam (another NSAID), which is not toxic to vultures. The retail sale of Diclofenac is banned by law in India; however, Diclofenac is still acquired illegally and applied to livestock.<p>Captive-breeding programs in India are aiming to conserve the species, and it is hoped that vultures can be released back in the wild when the environment is free of diclofenac. Joint efforts between the RSPB and the Zoological Society of London resulted in the first successful captive breeding in 2009. Two slender-billed vultures hatched and are being independently cared for in Haryana and West Bengal.
- 种群趋势
- declining
照片
分布
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