The
White-rumped Vulture (
Gyps bengalensis) is an
Old World vultureOld World vultures belong to the family Accipitridae, which also includes eagles, buzzards, kites, and hawks.Old World vultures are not closely related to the superficially similar New World vultures and condors, and do not share that group's good sense of smell. The similarities between the two...
closely related to the European
Griffon VultureThe Griffon Vulture is a large Old World vulture in the bird of prey family Accipitridae.The Griffon Vulture is long with a wingspan. In the nominate race the males weigh and females typically weigh , while in the Indian subspecies the vultures average...
(
Gyps fulvus). At one time it was believed to be closer to the
White-backed VultureThe White-backed Vulture is an Old World vulture in the family Accipitridae, which also includes eagles, kites, buzzards and hawks. It is closely related to the European Griffon Vulture, G. fulvus...
of Africa and was known as the
Oriental White-backed Vulture. The species was present in large numbers, in Southern and Southeastern Asia until the 1990s and declined rapidly in numbers since. In 1985 the species was described as "possibly the most abundant large bird of prey in the world" and often considered a nuisance but is now rare.
Description
The White-rumped Vulture is a typical vulture, with an unfeathered head and neck, very broad wings, and short tail feathers. It is much smaller than European Griffon. It has a white neck ruff. The adult's whitish back, rump, and underwing coverts contrast with the otherwise dark plumage. The body is black and the secondaries are silvery grey. The head is tinged in pink and bill is silvery with dark ceres. The nostril openings are slit-like. Juveniles are largely dark and take about four or five years to acquire the adult plumage. In flight, the adults show a dark leading edge of the wing and has a white wing-lining on the underside. The undertail coverts are black.
This is the smallest of the
GypsThe Gyps vultures are a genus of Old World vultures in the bird family Accipitridae, which also includes eagles, kites, buzzards and hawks....
vultures, but is still a very large bird. It weighs 3.5-7.5 kg (7.7-16.5 lbs), measures 75 – in length, and has a wingspan of 1.92–2.6 m (6.3–8.5 ft).
This vulture builds its nest on tall trees often near human habitations in northern and central
IndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
,
PakistanPakistan , officially the Islamic Republic of Pakistan is a sovereign state in South Asia. It has a coastline along the Arabian Sea and the Gulf of Oman in the south and is bordered by Afghanistan and Iran in the west, India in the east and China in the far northeast. In the north, Tajikistan...
,
NepalNepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India...
, and
southeast AsiaSoutheast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
, laying one egg. Birds form roost colonies. The population is mostly resident.
Like other
vultureVulture is the name given to two groups of convergently evolved scavenging birds, the New World Vultures including the well-known Californian and Andean Condors, and the Old World Vultures including the birds which are seen scavenging on carcasses of dead animals on African plains...
s it is a
scavengerScavenging is both a carnivorous and herbivorous feeding behavior in which individual scavengers search out dead animal and dead plant biomass on which to feed. The eating of carrion from the same species is referred to as cannibalism. Scavengers play an important role in the ecosystem by...
, feeding mostly from carcasses of dead
animalAnimals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...
s which it finds by soaring high in thermals and spotting other scavengers. It often moves in flocks. At one time, it was the most numerous of the vultures in India.
Within the well-supported clade of the genus
Gyps which includes Asian, African, and European populations, it has been determined that this species is basal with the other species being more recent in their species divergence.
Behaviour and ecology
These birds are usually inactive until the morning sun has warmed up the air with sufficient thermals to support their soaring. They circle and rise in altitude and join move off in a glide to change thermals. Large numbers were once visible in the late morning skies above Indian cities.
When a kill is found they quickly descend and feed voraciously, and will perch on trees nearby and are known to sometimes descend even after dark to feed on a carcass. When feeding at carcasses they are dominated over by
Red-headed VultureThe Red-headed Vulture , also known as the Asian King Vulture, Indian Black Vulture or Pondicherry Vulture,-Description:...
s
Sarcogyps calvus. A whole bullock has been said to have been cleaned up by a pack of vultures in about 20 minutes. In forests, the sight of their soaring was often the indication of a tiger kill. They may also swallow pieces of bone. Where water is available these birds bathe regularly and also drink water.
Allan Octavian HumeAllan Octavian Hume was a civil servant, political reformer and amateur ornithologist in British India. He was one of the founders of the Indian National Congress, a political party that was later to lead the Indian independence movement...
noted based on the observation of "hundreds of nests" that they always nested on large trees near habitations even when there were convenient cliffs in the vicinity. The preferred nesting trees were
BanyanFicus benghalensis, the banyan, is a large and extensive growing tree of the Indian subcontinent. Ficus benghalensis produces propagating roots which grow downwards as aerial roots. Once these roots reach the ground, they grow into woody trunks that can become indistinguishable from the main...
,
PeepulThe Sacred Fig, Ficus religiosa, or Bo-Tree , Peepal is a species of banyan fig native to India, Bangladesh, Nepal, Pakistan, Sri Lanka, southwest China and Indochina...
,
ArjunTerminalia arjuna is a tree of the genus Terminalia.-Description:...
, and
NeemAzadirachta indica is a tree in the mahogany family Meliaceae. It is one of two species in the genus Azadirachta, and is native to India growing in tropical and semi-tropical regions. Its fruits and seeds are the source of neem oil...
. The main nesting period was November to March with eggs being laid mainly in January. Nests are usually in clusters and isolated nests tend to be those of younger birds. Solitary nests are never used regularly and are sometimes taken over by the
Red-headed VultureThe Red-headed Vulture , also known as the Asian King Vulture, Indian Black Vulture or Pondicherry Vulture,-Description:...
and large owls such as
Bubo coromandus. Nests are nearly 3 feet in diameter and half a foot in thickness. Prior to laying an egg, the nest is lined with green leaves. A single egg is laid which is white with a tinge of bluish-green. Female birds are reported to destroy the nest on loss of an egg. They are usually silent but make hissing and roaring sounds at the nest or when jostling for food.
Trees on which they regularly roost are often painted white with their excreta and this acidity often kills the trees. This made them less welcome in orchards and plantations.
A freak case of a bird getting caught in the mouth of dying calf and dying trapped within has been noted.
MycoplasmaMycoplasma refers to a genus of bacteria that lack a cell wall. Without a cell wall, they are unaffected by many common antibiotics such as penicillin or other beta-lactam antibiotics that target cell wall synthesis. They can be parasitic or saprotrophic. Several species are pathogenic in humans,...
s have been isolated from tissues of the bird. Mallophagan parasites such as
Falcolipeurus and
Colpocephalum turbinatum have been collected from the species. Ticks,
Argas (Persicargas) abdussalami, have been collected in numbers from the roost trees of these vultures in Pakistan. A specimen in captivity lived for at least 12 years.
Jungle Crows have been seen to steal food brought by adults and regurgitated to young. They may sometimes feed on dead vultures of their own species while
Egyptian VultureThe Egyptian Vulture is a small Old World vulture, found widely distributed from southwestern Europe and northern Africa to southern Asia. It is the only living member of the genus Neophron. It has sometimes also been known as the White Scavenger Vulture or Pharaoh's Chicken...
s have also been noted to feed on dead vulture fledgelings.
In the Indian subcontinent
This species was very common, especially in the Gangetic plains of India and often seen nesting on the avenue trees within large cities in the region.
Hugh WhistlerHugh Whistler , F.Z.S., M.B.O.U. was an English ornithologist who worked in India. He wrote one of the first field guides to Indian birds and documented the distributions of in numerous notes in several journals apart from describing several new subspecies.-Life and career:Whistler was born in...
noted for instance in his guide to the birds of India that it "is the commonest of all the Vultures of India, and must be familiar to those who have visited the Towers of Silence in Bombay."
T. C. JerdonThomas Caverhill Jerdon was a British physician, zoologist and botanist. He is best remembered for his pioneering works on the ornithology of India...
noted that "[T]his is the most common Vulture of India, and is found in immense numbers all over the country, ... At Calcutta one may frequently be seen seated on the bloated corpse of some Hindoo floating up or down with the tide, its wing spread, to assist in steadying it..." Prior to the 1990s they were even seen as a nuisance, particularly to aircraft as they were often involved in
bird strikeA bird strike—sometimes called birdstrike, avian ingestion , bird hit, or BASH —is a collision between an airborne animal and a man-made vehicle, especially aircraft...
s. In 1990, the species had already become rare in Andhra Pradesh in the districts of Guntur and Prakasham. The hunting of the birds for meat by the Bandola (Banda) people there was attributed as a reason. A cyclone in the region during 1990 resulted in numerous livestock deaths and no vultures were found at the carcasses.
This species, as well as the Indian and
Slender-billed VultureThe Slender-billed Vulture is a recently recognized species of Old World vulture. For some time, it was categorized with its relative, the Indian Vulture, under the name of "Long-billed Vulture". However, these two species have non-overlapping distribution ranges and can be immediately told apart...
s have suffered a 99 percent population decrease in
IndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
and nearby countries since the early 1990s. The decline has been widely attributed to poisoning by
diclofenacDiclofenac is a non-steroidal anti-inflammatory drug taken to reduce inflammation and as an analgesic reducing pain in certain conditions....
, which is used as veterinary
non-steroidal anti-inflammatory drugNonsteroidal anti-inflammatory drugs, usually abbreviated to NSAIDs or NAIDs, but also referred to as nonsteroidal anti-inflammatory agents/analgesics or nonsteroidal Anti-inflammatory medicines , are drugs with analgesic and antipyretic effects and which have, in higher doses, anti-inflammatory...
(NSAID), leaving traces in cattle carcasses which when fed on leads to kidney failure in birds. Diclofenac was also found to be lethal at low dosages to other species in the genus
Gyps. Other NSAIDs were also found to be toxic, to
Gyps as well as other birds such as storks. Organochlorine pesticide was found from egg and tissue samples from around India varying in concentrations from 0.002 μg/g of DDE in muscles of vulture from Mudumalai to 7.30 μg/g in liver samples from vultures of Delhi. Dieldrin varied from 0.003 and 0.015 μg/g. These pesticide levels have not however been implicated in the decline. Another hypothesis is that they have been affected by
avian malariaAvian malaria is a parasitic disease of birds.-Etiology:Avian malaria is most notably caused by Plasmodium relictum, a protist that infects birds in tropical regions...
, as implicated in the extinctions of birds in the Hawaiian islands.
Birds were reported to adopt a drooped neck posture and this was considered a symptom of pesticide poisoning, but some studies suggest that this may be a thermoregulatory response since this posture is seen mainly during hot weather.
It has been suggested that rabies cases have increased in India due to the decline.
In Southeast Asia
In Southeast Asia, the near-total disappearance of the species predated the present diclofenac crisis, and probably resulted from the collapse of large wild ungulate populations and improved management of deceased livestock resulting in a lack of available carcasses for vultures.
Conservation
Currently, only the
CambodiaCambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...
and Burma populations are thought to be viable. It has been suggested that
MeloxicamMeloxicam is a nonsteroidal anti-inflammatory drug with analgesic and fever reducer effects. It is a derivative of oxicam, closely related to piroxicam, and falls in the enolic acid group of NSAIDs...
(another NSAID) as a veterinary substitute that is harmless to vultures would help in the recovery. Campaigns to ban the use of diclofenac in veterinary practice have been underway in several South Asian countries.
Conservation measures have included
reintroductionReintroduction is the deliberate release of a species into the wild in zones formerly inhabited by said species but where it has disappeared from for a number of reasons, from captivity or relocated from other areas where the species still survives in...
, captive-breeding programs and artificial feeding or "vulture restaurants". Two chicks, which were apparently the first captive-bred White-rumped Vultures ever, hatched in January 2007, at a facility at
PinjorePinjore is a town in Panchkula district in the Indian state of Haryana.-Demographics: India census, Pinjore had a population of 25,498. Males constitute 54% of the population and females 46%. Pinjore has an average literacy rate of 76%, higher than the national average of 59.5%: male literacy is...
. However, they died after a few weeks, apparently because their parents were an inexperienced couple breeding for the first time in their lives – a fairly common occurrence in birds of prey.
Other sources
- Ahmad, S. 2004. Time activity budget of Oriental White-backed Vulture (Gyps bengalensis) in Punjab, Pakistan. M. Phil. thesis, Bahauddin Zakariya University, Multan, Pakistan.
- Grubh, R. B. 1974. The ecology and behaviour of vultures in Gir Forest. Ph.D. dissertation, University of Bombay, Bombay, India.
- Grubh, R. B. 1988. A comparative study of the ecology and distribution of the Indian White-backed Vulture (Gyps bengalensis) and the Long-billed Vulture (G. indicus) in the Indian region. Pages 2763-2767 in Acta 19 Congressus Internationalis Ornithologici. Volume 2. Ottawa, Canada 22–29 June 1986 (H. Ouellet, Ed.). University of Ottawa Press, Ottawa, Ontario.
- Eck, S. 1981. [Thanatose beim Bengalgeier (Gyps bengalensis)]. Ornithologische Jahresberichte des Museums Heineanum 5-6:71-73.
- Naidoo, Vinasan 2008. Diclofenac in Gyps vultures : a molecular mechanism of toxicity. Ph.D. Thesis, University of Pretoria. Fulltext (Includes old photos showing their numbers)
External links