White-headed vulture

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White-headed vulture
Trigonoceps occipitalis -Las Aguilas Jungle Park, Tenerife, Spain-8a (4).jpg
At Las Águilas Jungle Park, Tenerife, Spain
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Trigonoceps
Lesson, 1842
Species:
T. occipitalis
Binomial name
Trigonoceps occipitalis
(Burchell, 1824)
TrigonocepsOccipitalisIUCN.svg
Range of T. occipitalis
  Resident
  Possibly Extant (resident)
  Non-breeding
  Probably extinct
  Extinct

The white-headed vulture (Trigonoceps occipitalis) is an Old World vulture endemic to Africa. Populations have been declining steeply in recent years due to habitat degradation and poisoning of vultures at carcasses. An extinct relative was also present in the Indonesian island of Flores during the Late Pleistocene, indicating that the genus was more widespread in the past. [2]

Contents

Description

The white-headed vulture is a medium-sized vulture, 72–85 centimetres (28–33 in) in length and with a wingspan of 207–230 centimetres (81–91 in). Females have an average weight of 4.7 kilograms (10 lb), while males are generally lighter at 4 kilograms (8.8 lb) or less. This species is unique among African vultures as it shows a degree of reversed sexual dimorphism, where females are somewhat larger than males. [3]

It has a pink beak and a white crest, and the featherless areas on its head are pale. It has dark brown upper parts and black tail feathers. The feathers on its lower parts and legs are white, giving it its diagnostic image from below. [4] [5] These vultures are easily distinguishable from all other vulture species as the plumage exhibits a strong contrast between black and white. Individual white-headed vultures can also be reliably identified based on a unique pattern in their median wing coverts. [3]

Distribution and habitat

The white-headed vulture is widely spread throughout sub-Saharan Africa, occurring from Senegal and Gambia east to Somalia and south to South Africa and Eswatini. It is locally uncommon to common. A total population of 10,500-18,750 individuals has been estimated, but newer estimates following recent declines suggest a population of just 5,500 individuals. It is estimated that 400 protected areas contain 1893 White-headed vulture nests, with 721 nests occurring in East Africa, 548 in Central Africa, 468 in Southern Africa and 156 in West Africa. [6] The species prefers mixed, dry woodland at low altitudes. It occurs at elevations of up to 4,000 m (13,000 ft) in Ethiopia, perhaps 3,000 m (9,800 ft) in Kenya, and can be found in thorny Acacia-dominated landscape in Botswana. It generally avoids human habitation [7] and are considered to be restricted to protected areas. For example, the Kruger National Park and neighboring conservation areas hold the largest population of the species in South Africa. [6]

Ecology

The species is long-lived and appears to be loyal to a territory where it remains resident. It builds nests in trees (mostly acacias or baobabs). [7] Senegalia species are also preferred, with nests occurring on the top of the canopy in low relief, flatter areas. [6] These vultures usually lay a single egg a couple of months after the rainy season has ended and the dry season is underway. [7] It is generally a solitary species and nests in isolated, possibly territorial pairs. [8] From a study across 73 pairs, the average productivity of 55 breeding attempts was 0.69 chicks per pair. White headed vultures are known to exhibit a characteristic breeding behaviour. From a study in the Kruger National Park, copulation only occurred on the nest and is described as a subtle and inconspicuous process that lasts approximately 15 to 20 seconds. Preceding actual copulation the female bird stands perpendicular to and in front of the male. The "head turning" behaviour, typically observed in other Aegypiine vultures, was not observed. The sound made by the birds during copulation is unusual and best described as a very deep squeak, but longer than a grunt. [8] The white-headed vulture is predominantly a carrion-eater; frequently flying lower than other vulture species, it is often the first species to turn up at a carcass. However, the species is probably also an active predator if the occasion arises. [7] For example, instances of pairs preying on species such as the mongoose (Galarella sanguinea), monitor lizard (Varanus spp), tree squirrel (Paraxerus cepapi) and scrub hare (Lepus saxatilis) have been recorded. In three of these four events, cooperative behaviour between the birds was apparent, thereby suggesting that this behaviour is not uncommon. There was also no observable agonistic behaviour between birds while feeding, and the birds appeared practiced and unaffected by the presence of an observer. These observations suggest that the vulture might be regular facultative predators. However, extensive field reports are lacking therefore further research is warranted. [9]

Additionally, the visual field of this vulture species is more similar to other predatory species such as the accipitrid hawk than to that of more closely related, carrion feeding Gyps vultures. Specifically, they have a significantly wider binocular field (30°, compared to the 20° of Gyps vultures), which is thought to help with the accurate placement and timing of the talons necessary to capture live prey. [10]

Conservation and threats

White-headed vulture populations have been declining since the early 1940s; it was classified as Vulnerable in the 2007 IUCN Red List. Recent indications that the species is rarer than previously thought have led to a status upgrade to Critically Endangered in 2015. [1]

The main threats to white-headed vulture populations are reductions in the availability of suitable food sources (carcasses of medium-sized mammals and ungulates) and the loss of habitat to the spread of urban and agricultural developments. Poisoning through baits set for other carnivores such as jackals and hyenas, as well as targeted poisoning of vultures (by poachers who seek to prevent vultures from drawing attention to an illegal kill), is also an important factor. Secondary causes of decline is exploitation for the international trade in raptors and use in traditional medicines. The species is highly sensitive to land-use and tends to depart from degraded habitat, leading to high concentrations in protected areas. Potential introduction of the anti-inflammatory drug Diclofenac , which is fatal to all vultures of the closely related genus Gyps when ingested at livestock carcasses, may represent a potential future threat. [1]

On the 20th of June 2019, the carcasses of 468 white-backed vultures, 17 white-headed vultures, 28 hooded vultures, 14 lappet-faced vultures and 10 cape vultures, altogether 537 vultures, besides 2 tawny eagles, were found in northern Botswana. It is suspected that they died after eating the carcasses of 3 elephants that were poisoned by poachers, possibly to avoid detection by the birds, which help rangers to track poaching activity by circling above where there are dead animals. [11] [12] [13] [14]

Related Research Articles

<span class="mw-page-title-main">Vulture</span> Common name for a type of bird

A vulture is a bird of prey that scavenges on carrion. There are 23 extant species of vulture. Old World vultures include 16 living species native to Europe, Africa, and Asia; New World vultures are restricted to North and South America and consist of seven identified species, all belonging to the Cathartidae family. A particular characteristic of many vultures is a bald, unfeathered head. This bare skin is thought to keep the head clean when feeding, and also plays an important role in thermoregulation.

<span class="mw-page-title-main">Old World vulture</span> Informal group of birds

Old World vultures are vultures that are found in the Old World, i.e. the continents of Europe, Asia and Africa, and which belong to the family Accipitridae, which also includes eagles, buzzards, kites, and hawks.

<span class="mw-page-title-main">Eurasian griffon vulture</span> Species of bird

The Eurasian griffon vulture is a large Old World vulture in the bird of prey family Accipitridae. It may also be known as the Griffon vulture, though it may be used for the genus as a whole. It is not to be confused with a different species, Rüppell's griffon vulture. It is closely related to the white-backed vulture.

<span class="mw-page-title-main">Himalayan vulture</span> Species of bird

The Himalayan vulture or Himalayan griffon vulture is an Old World vulture native to the Himalayas and the adjoining Tibetan Plateau. It is one of the two largest Old World vultures and true raptors. It is listed as Near Threatened on the IUCN Red List. It is not to be confused with the griffon vulture, which is a similar species.

<span class="mw-page-title-main">White-rumped vulture</span> Species of bird

The white-rumped vulture is an Old World vulture native to South and Southeast Asia. It has been listed as Critically Endangered on the IUCN Red List since 2000, as the population severely declined. White-rumped vultures die of kidney failure caused by diclofenac poisoning. In the 1980s, the global population was estimated at several million individuals, and it was thought to be "the most abundant large bird of prey in the world". As of 2021, the global population was estimated at less than 6,000 mature individuals.

<span class="mw-page-title-main">Indian vulture</span> Species of vulture

The Indian vulture is an Old World vulture native to India, Pakistan and Nepal. It has been listed as Critically Endangered on the IUCN Red List since 2002, as the population severely declined. Indian vultures died of kidney failure caused by diclofenac poisoning. It breeds mainly on hilly crags in central and peninsular India.

<span class="mw-page-title-main">Hooded vulture</span> Species of bird

The hooded vulture is an Old World vulture in the order Accipitriformes, which also includes eagles, kites, buzzards and hawks. It is the only member of the genus Necrosyrtes, which is sister to the larger Gyps genus, both of which are a part of the Aegypiinae subfamily of Old World vultures. It is native to sub-Saharan Africa, where it has a widespread distribution with populations in southern, East and West Africa. It is a scruffy-looking, small vulture with dark brown plumage, a long thin bill, bare crown, face and fore-neck, and a downy nape and hind-neck. Its face is usually a light red colour. It typically scavenges on carcasses of wildlife and domestic animals. Although it remains a common species with a stable population in the lower region of Casamance, some areas of The Gambia, and Guinea-Bissau, other regions such as Dakar, Senegal, show more than 85% losses in population over the last 50 years. Threats include poisoning, hunting, loss of habitat and collisions with electricity infrastructure, and the International Union for Conservation of Nature has rated its conservation status as "critically endangered" in their latest assessment (2022). The highest current regional density of hooded vultures is in the western region of The Gambia.

<span class="mw-page-title-main">Lappet-faced vulture</span> Species of bird

The lappet-faced vulture or Nubian vulture is an Old World vulture belonging to the bird order Accipitriformes, which also includes eagles, kites, buzzards and hawks. It is the only member of the genus Torgos. It is not closely related to the superficially similar New World vultures, and does not share the good sense of smell of some members of that group.

<span class="mw-page-title-main">Egyptian vulture</span> Species of Old World vultures of the genus Neophron

The Egyptian vulture, also called the white scavenger vulture or pharaoh's chicken, is a small Old World vulture and the only member of the genus Neophron. It is widely distributed from the Iberian Peninsula and North Africa to India. The contrasting underwing pattern and wedge-shaped tail make it distinctive in flight as it soars in thermals during the warmer parts of the day. Egyptian vultures feed mainly on carrion but are opportunistic and will prey on small mammals, birds, and reptiles. They also feed on the eggs of other birds, breaking larger ones by tossing a large pebble onto them.

<span class="mw-page-title-main">White-backed vulture</span> Species of bird

The white-backed vulture is an Old World vulture in the family Accipitridae, which also includes eagles, kites, buzzards and hawks. It is the most common vulture species in the continent of Africa.

<span class="mw-page-title-main">Cinereous vulture</span> Species of bird

The cinereous vulture is a large raptor in the family Accipitridae and distributed through much of temperate Eurasia. It is also known as the black vulture, monk vulture and Eurasian black vulture. With a body length of 1.2 m, 3.1 m (10 ft) across the wings and a maximum weight of 14 kg (31 lb), it is the largest Old World vulture and largest member of the Accipitridae family.

<span class="mw-page-title-main">Rüppell's vulture</span> Species of bird

Rüppell's vulture, also called Rüppell's griffon vulture, named after Eduard Rüppell, is a large bird of prey, mainly native to the Sahel region and East Africa. The current population of 22,000 is decreasing due to loss of habitat, incidental poisoning, and other factors. Known also as Rüppell's griffon, Rueppell's griffon, Rüppell's griffin vulture, Rueppell's vulture and other variants, it is not to be confused with a different species, the griffon vulture. Rüppell's vulture is considered to be the highest-flying bird, with confirmed evidence of a flight at an altitude of 11,300 m (37,000 ft) above sea level.

<span class="mw-page-title-main">Tawny eagle</span> Species of bird

The tawny eagle is a large bird of prey. Like all eagles, it belongs to the family Accipitridae. Its heavily feathered legs mark it as a member of the subfamily Aquilinae, also known as booted eagles. Tawny eagles have an extensive but discontinuous breeding range that constitutes much of the African continent as well as the Indian subcontinent, with rare residency in the southern Middle East. Throughout its range, it favours open dry habitats such as semideserts, deserts steppes, or savanna plains. Despite its preference for arid areas, the species seldom occurs in areas where trees are entirely absent. It is a resident breeder which lays one to three eggs in a stick nest most commonly in the crown of a tree. The tawny eagle is perhaps the most highly opportunistic of all Aquilinae, and often scavenges on carrion or engages in kleptoparasitism towards other carnivorous animals but is also a bold and active predator, often of relatively large and diverse prey. It is estimated that tawny eagles can reach the age of 16 years old. Nonetheless, precipitous declines have been detected throughout the tawny eagle's range. Numerous factors, particularly loss of nesting habitat due to logging and global warming, as well as persecution and other anthropogenic mortality are driving the once numerous tawny eagle perhaps to the brink of extinction.

<span class="mw-page-title-main">Cape vulture</span> Species of bird

The Cape vulture or Cape griffon, also known as "Kolbe's vulture", is an Old World vulture in the family Accipitridae. It is endemic to southern Africa, and lives mainly in South Africa, Lesotho, Botswana, and in some parts of northern Namibia. It nests on cliffs and lays one egg per year. In 2015, it had been classified as Endangered on the IUCN Red List, but was down-listed to Vulnerable in 2021 as some populations increased and have been stable since about 2016. These majestic birds help to clean the environment by eating carcasses.

<span class="mw-page-title-main">Red-headed vulture</span> Species of bird

The red-headed vulture, also known as the Asian king vulture, Indian black vulture or Pondicherry vulture, is an Old World vulture mainly found in the Indian subcontinent, with small disjunct populations in some parts of Southeast Asia.

<span class="mw-page-title-main">Bateleur</span> Species of bird

The bateleur is a medium-sized eagle in the family Accipitridae. It is often considered a relative of the snake eagles and, like them, it is classified within the subfamily Circaetinae. It is the only member of the genus Terathopius and may be the origin of the "Zimbabwe Bird", the national emblem of Zimbabwe. Adult bateleurs are generally black in colour with a chestnut colour on the mantle as well as also on the rump and tail. Adults also have gray patches about the leading edges of the wings with bright red on their cere and their feet. Adults also show white greater coverts, contrasting with black remiges in males, gray patches on the underwing primaries and black wingtips. The juvenile bateleur is quite different, being largely drab brown with a bit of paler feather scaling. All bateleurs have extremely large heads for their size, rather small bills, large feet, relatively short legs, long, bow-like wings and uniquely short tails, which are much smaller still on adults compared to juvenile birds.

<span class="mw-page-title-main">Jatayu Conservation Breeding Centre, Pinjore</span> Critically Endangered Bird Breeding Centre in Haryana, India

The Jatayu and Sparrow Conservation Breeding Centre (JCBC), is the world's largest facility for the breeding and conservation of Indian vultures (गिध) and the house sparrow. It is located within the Bir Shikargah Wildlife Sanctuary in the town of Pinjore in the State of Haryana, India. It is run by the Haryana Forests Department and Bombay Natural History Society with the help of British nature conservation charity Royal Society for the Protection of Birds. It is 8 kilometres (5.0 mi) from Pinjore and covers 5 acres (2.0 ha).

A vulture restaurant is a site where carrion, decaying flesh from dead animals, is deposited in order to be consumed by vultures, and is sometimes referred to more generally as supplemental feeding or provisioning. These stations can also be referred to as vulture feeding sites, vulture feeding stations, and vulture safe zones. This supplemental feeding practice is used to provide vultures with reliable, non-contaminated food sources or to aid in monitoring schemes. Vulture restaurants have been instituted as a method of vulture conservation in Europe and Africa since the 1960's and 70's, when vulture populations began to decline. This strategy is used because often population declines are attributed to low food availability, food contamination or insufficient nutritional quality, or feeding from human areas leading to conflict. Notably, large vulture population declines in South Asia, referred to as the Asian or Indian vulture crisis, and Africa, referred to as the African vulture crisis, have brought renewed attention to the uses and impacts of vulture restaurants. Vulture restaurants are used in Asia, Africa, Europe, and North America for various conservation and management plans. They can help combat food-derived threats to vultures, such as diclofenac or lead contamination or conflict with ranchers and poachers. The first vulture restaurant was built in South Africa in 1966. Vulture restaurants operate in a number of countries, including Nepal, India, Cambodia, South Africa, Eswatini, and Spain.

<span class="mw-page-title-main">African vulture trade</span>

The African vulture trade involves the poaching, trafficking, and illegal sale of vultures and vulture parts for bushmeat and for ritual and religious use, like traditional medicines, in Sub-Saharan Africa. This illegal trade of vultures and vulture parts is contributing to a population crisis on the continent. In 2017, the IUCN Red List categorized 7 of Africa's 11 vulture species as globally endangered or critically endangered. Recent research suggests that 90% of vulture species declines in Africa may be due to a combination of poisoning and illegal wildlife trade for medicinal use and/or bushmeat. All trade of African vultures is illegal, as these birds are protected by international laws.

<span class="mw-page-title-main">African vulture crisis</span> Ecological disaster in Africa

The African vulture crisis is the name given to the ongoing population decline in several Old World vulture species across Africa. Steep population declines have been reported from many locations across the continent since the early 2000s. The causes are mainly poisoning from baited animal carcasses, and the illegal trade in vulture body parts for traditional medicine. Available data suggest that the African vulture crisis may similar in scale to the Indian vulture crisis, but more protracted and less well documented.

References

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  11. "Over 500 Rare Vultures Die After Eating Poisoned Elephants In Botswana". Agence France-Press . NDTV. 2019-06-21. Retrieved 2019-06-28.
  12. Hurworth, Ella (2019-06-24). "More than 500 endangered vultures die after eating poisoned elephant carcasses". CNN . Retrieved 2019-06-28.
  13. Solly, Meilan (2019-06-24). "Poachers' Poison Kills 530 Endangered Vultures in Botswana". Smithsonian . Retrieved 2019-06-28.
  14. Ngounou, Boris (2019-06-27). "BOTSWANA: Over 500 vultures found dead after massive poisoning". Afrik21. Retrieved 2019-06-28.