Palm vulture

Palm vulture
	Palm vulture ( Gypohierax angolensis )
Systematics
Subclass :	New-jawed birds (Neognathae)
Order :	Birds of prey (Accipitriformes)
Family :	Hawk species (Accipitridae)
Subfamily :	Gypaetinae
Genre :	Palm vulture
Type :	Palm vulture
Scientific name of the genus
	Gypohierax
	Rüppell , 1836
Scientific name of the species
	Gypohierax angolensis
	( Gmelin , 1788)

Immature palm vulture

Aerial image of the palm vulture

The palm vulture ( Gypohierax angolensis ) is a bird of prey from the hawk family (Accipitridae). The genus Gypohierax is monotypical with the palm vulture as the only species. The closed distribution area extends over large parts of the central and western Afrotropis . In the Eastern Afrotropic Islands, the occurrences are disjoint and largely confined to the coasts. The species primarily inhabits forest and woodland, or agricultural areas interspersed with forest mostly near water. In the populated landscapes there are almost always occurrences of palms of the genus Raphia or oil palms , the fruits of which make up a significant part of the palm vulture's diet. The animals therefore also inhabit the peripheral areas of oil palm plantations. The species is quite common and the population appears to be stable. The population situation of the palm vulture was classified in the IUCN Red List of Threatened Species in 2016 as “ Least Concern (LC) ” = “not endangered”.

description

Palm vultures are medium-sized, powerfully built birds of prey with broad but relatively short wings, a very short rounded tail, a rather small head and a powerful long beak. The face is largely feathered and another narrow, feathered area extends from the base of the lower mandible to the rear, to about under the ear covers. Females are only slightly larger and heavier than males; the sexes are otherwise no different. The body length is 57–65 cm, the wingspan 135–155 cm and the weight 1.2–1.8 kg.

Adult birds are very distinctive in color. The shoulder feathers, the large upper wing coverts, the arm wings , the tips of the hand wings and the bases of the control feathers are black. The entire rest of the plumage is in contrasting plain white. The featherless skin on the head is red or orange-red, the iris yellow. The beak is yellowish, the wax skin on the beak blue-gray. The legs and toes are pale orange to brownish yellow.

Young birds that have just flown out look completely different. Overall, the animals are quite plain beige-brown. The lightest brown shows the head, wing-coverts and the underside of the trunk. Upper back and shoulder feathers are darker brown, wings and control feathers are even darker blackish brown. The featherless skin on the head is yellowish gray or brownish yellow, the iris dark brown. The bill and wax skin are yellowish gray, legs and toes are pale dirty white to gray-brown. The full adult dress is achieved at the age of 4 years (5th calendar year).

Vocalizations

The animals are known to be comparatively unrepentant. What is described, however, is a kind of growling while eating, a duck-like croaking at sleeping places and croaking calls, hissing whistling tones as well as barking and other throaty sounds in various contexts.

Systematics

No subspecies are recognized for the palm vulture. The systematic position of the species within the hawk-like species has long been unclear. Recent molecular genetic studies of the mitochondrial DNA and the DNA of the cell nucleus place the palm vulture in the exclusively old-world subfamily Gypaetinae ; it is in a sister taxon relationship to the three other species of this very heterogeneous subfamily ( Madagascar hawk ( Eutriorchis astur ), bearded vulture ( Gypaetus barbatus ) and Egyptian vulture ( Neophron percnopterus )).

distribution and habitat

The largely closed distribution area includes large parts of the central and western Afrotropic islands between 15 ° N and 29 ° S. In a west-east direction, the closed area extends from Senegal and Gambia , across southern Mali and central Nigeria , to the south of Sudan and from there south to northern Angola and Zambia . This is followed to the east by more or less disjoint deposits, largely restricted to coastal areas, in the extreme northeast of South Africa , in Mozambique, as well as in Kenya and Tanzania . The total distribution area covers about 11.3 million km².

The species primarily inhabits forest and woodland or agricultural areas interspersed with forest mostly near water. In the populated landscapes there are almost always occurrences of palms of the genus Raphia or oil palms . The animals also colonize the fringes of oil palm plantations.

Hunting style and diet

The palm vulture is one of the few species of birds of prey whose diet consists to a large extent of fruits. They can make up 58 to 65% of the food in adult birds and up to 92% in young birds. In large parts of the distribution area, the main food is fruits of palms of the genus Raphia or oil palms , as well as dates and upa fruits , for example . The food spectrum of the palm vulture is very broad and includes not only fruits but also fish and other small vertebrates of all kinds, snails, crabs and other invertebrates as well as carrion of all sizes.

The hunt for animals takes place from the hide, in search flight and - in mangroves , along banks, or next to bushfires - also on foot. Fish are grabbed from the surface of the water as they fly over them. To eat fruit, the palm vulture climb around trees quite skillfully, and depending on the species, the fruit is swallowed completely or first removed from the shell and then consumed piece by piece.

Reproduction

Gypohierax angolensis

The species breeds in single pairs. The courtship consists of common or individual circles, occasionally the animals show nosedives or throw themselves on their backs in flight. The breeding season varies depending on the geographical distribution. It falls in West and Central Africa from October / November to April / May, in Angola from May to November / December, in East Africa from June to December / January and in Zululand from August to January. The 60 to 90 cm wide and 30 to 60 cm high nest is at a height of 6–60 m in the crown of palms, baobabs , Bombax sp. and other large trees. It consists of branches and is mainly padded with leaves, sisal fibers , inflorescences from palm trees and excrement. The clutch consists of only one egg, which is incubated for around 35–50 days. The young bird leaves the nest between 85 and 90 days of age.

Existence and endangerment

For the early 1990s, the world population was estimated at around 240,000 individuals; more recent figures are not available. The species is quite common, at least in parts of its range. In many forest areas in the lowlands of West and Central Africa, the palm vulture is the most common larger bird of prey. The population is apparently stable, and therefore the palm vulture is classified by the IUCN as not endangered ("least concern").

swell

Individual evidence

↑ Gypohierax angolensis in the endangered Red List species the IUCN 2016 Posted by: BirdLife International, 2016. Accessed November 29 of 2019.
↑ HRL Lerner and DP Mindell: Phylogeny of eagles, Old World vultures and other Accipitridae based on nuclear and mitochondrial DNA. In: Molecular Phylogenetics and Evolution. Vol. 37, 2005, pp. 327-346.
↑ BirdLife International (2010) Species factsheet: Gypohierax angolensis. ( online , accessed August 10, 2010).
^ J. Ferguson-Lees, DA Christie: Raptors of the World. Christopher Helm, London 2001, ISBN 0-7136-8026-1 , p. 413.

literature

J. Ferguson-Lees, DA Christie: Raptors of the World. Christopher Helm, London 2001, ISBN 0-7136-8026-1 , pp. 110-111 and 411-413.

Web links

Gypohierax angolensis in the red list of endangered species of the IUCN 2016. Posted by: BirdLife International, 2016. Accessed November 29 of 2019.