Hooded vulture

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Hooded vulture
Hooded vulture (Necrosyrtes monachus).jpg
in Gambia
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Necrosyrtes
Gloger, 1841
Species:
N. monachus
Binomial name
Necrosyrtes monachus
(Temminck, 1823)
Synonyms

Neophron monachus(Temminck, 1823)

The hooded vulture (Necrosyrtes monachus) 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. [2] [3] It is native to sub-Saharan Africa, where it has a widespread distribution with populations in southern, East and West Africa. [4] [5] 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. [5] [6] 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). [6] The highest current regional density of hooded vultures is in the western region of The Gambia. [7]

Contents

Etymology

The common name "hooded vulture" stems from the fact that the vulture has a small patch of downy feathers that runs along the back of its neck to the crown of its head, making it look like it is wearing a fluffy, cream-colored hood. [8] The scientific name, Necrosyrtes monachus, can be broken down into 3 sections: "necro", since it feeds on carrion; "syrtes" which means "quicksand" or "bog" and "monachus" which is Latin for "monk" and relates to the hood of the vulture. [9]

Description

Appearance

The hooded vulture is a typical vulture, with a head that is usually pinkish-white, but flushes red when agitated, [10] and a grey to black "hood". It has fairly uniform dark brown body plumage. It has broad wings for soaring and short tail feathers. This is one of the smaller Old World vultures. They are 62–72 cm (24–28 in) long, have a wingspan of 155–180 cm (61–71 in) and a body weight of 1.5–2.6 kg (3.3–5.7 lb). [11] Both sexes are alike in appearance, although females often have longer eyelashes than males. Juveniles look like adults, only darker and plainer, and body feathers have a purplish sheen. [9]

Voice

Usually silent, but gives a shrill, sibilant whistle during copulation, and thin squealing calls both at nests and carcasses. [9]

Nesting, breeding and behaviour

It breeds in a stick nest in trees (often palms) in much of Africa south of the Sahara, laying one egg. Birds may form loose colonies. The population is mostly resident and sedentary, rarely moving more than 200 km. [9]

Distribution

Although hooded vultures have relatively small home ranges, they are widely distributed across Africa. It occurs in Senegal, Mauritania, Guinea-Bissau, The Gambia, Niger and Nigeria in West Africa; in East Africa it is found in Chad, Sudan, South Sudan, Ethiopia and Somalia; in southern Africa it has been recorded in northern Namibia, Botswana, Zimbabwe, Mozambique and South Africa. [6]

Within South Africa, the species is essentially restricted to the Kruger National Park and surrounding protected areas in Mpumalanga and Limpopo provinces, though vagrants have been recorded further west in Kwa-Zulu Natal and Kgalagadi Transfrontier Park. [12]

Ecology

Vultures feeding on a dog carcass in Gambia, West Africa Vultures and dog - The Gambia. West Africa (32740095391).jpg
Vultures feeding on a dog carcass in Gambia, West Africa

Like other vultures hooded vultures are scavengers, feeding mostly from carcasses of dead animals and waste which they find by soaring over savanna and around human habitation, including waste tips and abattoirs. [5] They do however also feed on insects, and conglomerate in large numbers during insect emergences, for example termite emergences where they associate with Steppe Eagles. [6] [9] They are non-specialised, highly versatile scavengers and are commensal with humans in West Africa. [13] They often move in flocks (50-250 individuals) in West Africa, especially when foraging at abattoirs or elephant carcasses, [9] while in southern Africa they are solitary and secretive, making them hard to spot when nesting. [12] They are known to follow scavenging African wild dogs and hyaenas. [9]

This vulture is typically unafraid of humans, and frequently gathers around habitation. It is sometimes referred to as the “garbage collector” by locals.[ citation needed ] In Ghanaian universities, a significantly higher number of hooded vultures exist in the residential parts of the campus relative to the non-residential parts, and densities are correlated with the academic calendar, with numbers of individuals increasing during school terms. [14] 45% of students at these campuses are defecated on by hooded vultures at least once a month, according to interviews. [14]

Southern African hooded vulture populations have smaller home ranges than most other Old World vulture species for which data exists, though less is known about home ranges of East and West African populations. [4] They are most active during the day, and their ranges are smaller in the dry breeding season, when their movement is constrained by a nest site location to which they must return regularly to incubate their eggs and provision their fledglings. [4] In both the northern and southern hemisphere populations, breeding takes place in the dry summer season. [6]

They prefer to build nests in well-foliaged trees along watercourses, with the nest placed a prominent fork within the tree canopy at an average height of over 15m. [12] They have however also been observed in a variety of biomes, some where tall trees are rare. They have been recorded in open grasslands, deserts, wooded savanna, forest edges and along coasts. [6] They tend to occur in higher densities where populations of larger Gyps vultures are low or nonexistent. [15] It occurs up to 4,000 m, but is most numerous below 1,800 m. [6]

Hooded vultures lay a clutch of one egg, and the incubation period lasts 46-54 days, followed by a fledging period of 80-130 days. Young are dependent on their parents for a further 3-4 months after fledging. [15] Measurements of nesting success at the Olifants River Private Nature Reserve, South Africa showed success of 0.44-0.89 offspring per pair per year in 2013 and 0.50-0.67 offspring per pair per year in 2014. [6]

While the populations in Gambia are relatively stable, it is declining almost everywhere else in its range at an average rate of 83% (range 64–93%) over 53 years (3 generations). [6] [16] Its total population is estimated at a maximum of 197 000 individuals. [17] Some declines have been reported to have occurred in only 20 years, almost approaching the speed and extent of the Asian vulture crisis of the 1990s. [16] The highest regional density of hooded vultures is in western Gambia. [7]

Status and threats

The species has been uplisted from its previous IUCN status of endangered to critically endangered, since the species is going through a very steep decline in population, owing to various factors including poisoning, hunting, habitat loss and degradation of habitat. [18] Hunting is the most well-known threat to the species, however, poisoning has been shown to have the highest impact on the population. Poisoning of the species has been both unintentional and intentional, with unintentional poisoning being caused through the poisoning of other animals which the species feeds on. Hunting on the other hand is caused by vultures being used by people in traditional medicine and cultural beliefs and as a food source, particularly in West and southern Africa. [19] [16] Researchers interviewed vendors in street markets in northern Nigeria who were selling parts or entire carcasses of hooded vultures as well as other African vulture species (though hooded vultures made up 90% of vultures on sale). They found that 40% of traders were selling the vultures for spiritual healing and 25% for human consumption. [20]

Many West and southern African cultures believe vulture body parts cure a range of physical and mental illnesses, improve success in gambling and business ventures, or increase intelligence in children. [16] Consumption of vultures as bushmeat in Nigeria and Ivory Coast may be of regional concern, but smoked vulture meat is traded and consumed internationally. [16] Secondary poisoning with carbofuran pesticides at livestock baits being used to poison mammalian predators is also an issue in East Africa. [6]

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 over the locations of dead animals. [21] [22] [23] [24]

The species may also be threatened by avian influenza (H5N1), from which it appears to suffer some mortality and which it probably acquires from feeding on discarded dead poultry. [25] Another suggested cause of decline is the decline in the number of trees preferred by hooded vultures for nesting, such as Ceiba pentandra in Senegal. [6]

Conservation action

Raptors are protected in many West African and Northeastern countries and in South Africa under the United Nations Convention on the Conservation of Migratory Species of Wild Animals (CMS), in the Memorandum of Understanding on the Conservation of Migratory Birds of Prey in Africa and Eurasia (the ‘Raptors MoU’). [26] This plan includes the Hooded vulture. [27]

Systematic monitoring and protection schemes for African raptors, including the hooded vulture, exist and some populations occur within protected areas. [6] It has been suggested that the best way to slow the decline of vulture populations in Africa, and avoid a massive decline on the scale of the Asian vulture crisis of the 1990s in which populations declined 95% because of the veterinary drug Diclofenac used in livestock whose carcasses were fed on by vultures, pesticides and poisons need to be regulated and limited by governments in countries where the hooded vulture occurs. [16]

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">Palm-nut vulture</span> Species of bird

The palm-nut vulture or vulturine fish eagle, is a large bird of prey in the family Accipitridae. It is the only member of the genus Gypohierax.

<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 family of birds.

<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 in the monotypic genus Neophron. It is widely distributed from the Iberian Peninsula, North Africa, West Asia and 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">Secretarybird</span> Bird of prey

The secretarybird or secretary bird is a large, mostly terrestrial, bird of prey. Endemic to Africa, it is usually found in the open grasslands and savanna of the sub-Saharan region. John Frederick Miller described the species in 1779. A member of the order Accipitriformes, which also includes many other diurnal birds of prey such as eagles, hawks, kites, vultures, and harriers, it is placed in its own family, Sagittariidae.

<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 former population of 22,000 has been 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">Lizard buzzard</span> Species of bird

The lizard buzzard, or lizard hawk, is a bird of prey in the family Accipitridae. It is native to Sub-Saharan Africa. Despite its name, it may be more closely related to the Accipiter hawks than the Buteo buzzards.

<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, also known as Cape griffon and 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.

<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">Pygmy falcon</span> Species of bird

The African pygmy falcon —or simply pygmy falcon—is a diminutive raptor native to eastern and southern Africa. It is the sole species in its monotypic genus, Polihierax. The pygmy falcon is the smallest bird of prey on the African continent, and among the smallest raptors on earth; only the Asian falconets are smaller, weighing roughly 30-40 grams less and measuring about 5 cm shorter from head-to-tail.

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

The white-headed vulture 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.

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

The jackal buzzard is a fairly large African bird of prey. The taxonomy of this species has caused some confusion in the past and it almost certainly belongs in a species complex with other African Buteo species. Some taxonomists have considered this species, the Archer's buzzard, and the augur buzzard to be the same superspecies. Many taxonomists consider them all to be distinct, having different calls, different home ranges and variations in plumage. This is a species that lives among mountains, and on adjacent savanna and grassland. It is resident and non-migratory throughout its range.

<span class="mw-page-title-main">Southern black flycatcher</span> Species of bird

The southern black flycatcher is a small passerine bird of the genus Melaenornis in the flycatcher family, Muscicapidae, native to open and lightly wooded areas of eastern and southern Africa.

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

Gurney's sugarbird is a medium-sized passerine endemic to the mid- and high-altitude grassland velds in southern Africa. It belongs to the family Promeropidae, which contains one genus, Promerops, and two species. Gurney's sugarbird feeds on nectar from Protea bushes as well as on small insects. This bird is characterized by its long, graduated tail and decurved beak.

<span class="mw-page-title-main">African vulture trade</span> Use of vulture for various reasons in Sub-Saharan Africa

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 be similar in scale to the Indian vulture crisis, but more protracted and less well documented.

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