Brown-cheeked hornbill

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Brown-cheeked hornbill
Brown-cheeked hornbills, the male in front, the female in the back

Brown-cheeked hornbills, the male in front, the female in the back

Systematics
Sub-stem : Vertebrates (vertebrata)
Class : Birds (aves)
Order : Hornbills and hops (Bucerotiformes)
Family : Hornbills (Bucerotidae)
Genre : African throat hornbills ( Bycanistes )
Type : Brown-cheeked hornbill
Scientific name
Bycanistes cylindricus
( Temminck , 1831)
Drawing of a brown cheek hornbill skull, male

The brown-cheeked hornbill ( Bycanistes cylindricus ) is a monotypic bird art within the family of hornbills . Its distribution area is in western sub-Saharan Africa . Some ornithologists consider it to be a super species, along with the Babali hornbill . The Babali hornbill was also classified as a subspecies of the brown-cheeked hornbill for a while.

The IUCN states that the brown-cheeked hornbird's population is endangered ( vulnerable ).

features

The brown cheek hornbill reaches a body length of 60 to 70 centimeters. The tail feathers account for an average of 24.4 centimeters in males and 23.3 centimeters in females. The males have a beak between 14.5 and 16.5 centimeters. The beak of the females remains slightly smaller and is 12.5 to 16.5 centimeters in length. The weight is about 900 grams. The male's beak attachment has the shape of an upside-down chopping knife and is a dirty white color, while the significantly smaller part of the female is the same brownish color as the beak.

Appearance of the males

In the male, the head, neck, back and underside of the body are mostly shiny black. The feathers on the cheeks and on the throat have the eponymous brown seams. The rump, the upper and lower tail covers and the belly are white. The tail is white with a broad white central band. The outer hand wings and the arm wings are white. The beak and the beak attachment are cream-colored. The featherless skin around the eyes is red. The eyes are crimson, the legs and feet are black.

Appearance of females and fledglings

The female resembles the male in plumage. It is smaller and has a dust-gray beak with a black-brown beak base and a blue-gray beak tip. The beak attachment is significantly smaller than that of the male and is dark in color. The featherless skin around the eye is pale pink to cream in color. The eyes are brown. The legs and feet are black.

Fledglings have a plumage like the adult birds. Their beak, however, is even smaller and pale yellow in color. The beak attachment is missing or only slightly developed. The eyes are gray.

Possible confusion

In the distribution area of ​​the brown- cheeked hornbill both the gray-cheeked hornbill and the screech hornbird , belonging to the same genus, occur. The gray-cheeked hornbill is of a similar size. However, the beak attachment is darker, the tail feathers are black with a white tip. The middle pair of tail feathers is black. The hornbill is significantly smaller, has a smaller beak and a barely developed beak attachment.

distribution

The brown cheek hornbill has a very large distribution area. It occurs in Sierra Leone, southern Guinea, Liberia, the Ivory Coast, Ghana and Togo.

The habitat are primary forests of the lowlands.

food

Like most hornbills, the brown-cheeked hornbill is omnivorous, but it covers most of its nutritional needs with fruits. Up to 90 individuals of this species can gather in very abundantly fruit-bearing trees. The brown cheek hornbill lives mostly in pairs or in small family groups, which consist of the breeding pair and this year's young bird.

He looks for his food mainly in tree tops. In fruit-bearing trees it is able to chase away screaming hornbills. Monkeys and French hornbills , on the other hand, are more assertive than the brown-cheeked hornbill. Figs play a major role in the hornbill, as in many other species. However, it also hunts insects such as grasshoppers, praying mantises, dragonflies, flying ants, beetles and wasps. It also eats eggs and nestlings from weaver birds such as the village weaver . To do this, he either destroys the nest or pushes his beak into the nest entrance and then tilts the nest so that he can reach the contents of the nest with the beak contents.

Reproduction

The reproductive biology of the brown-cheeked hornbird is still largely unexplored. For example, the clutch size and the color of the eggs have not yet been described. There is an observation of two nestlings in a breeding pair, but usually a breeding pair is only observed with one young bird. The closely related hornbill found in East Africa is known to consist of one or two eggs in this clutch. A young bird usually grows up in the wild.

According to current knowledge, the breeding time of the hornbill is not tied to any particular season. Like all hornbill species, it is a cave breeder. It prefers natural tree hollows at a height of 20 to 25 meters above the ground. The entrance to the brood cavity is sealed except for a narrow gap. In all of the hornbill species examined in more detail, the breeding cave is sealed by the female. The male feeds the female and later the young bird through the remaining gap. The male usually carries the fruit in the throat to the nest and chokes them out again. The male only occasionally bears fruit in its beak to the nest. The male visits the nest between 14 and 18 times a day. The female that sits in the breeding cave goes through the moulting during the breeding season. This moulting is not a simultaneous moulting of the large plumage. This way the female retains her ability to fly during the breeding season. It is not yet known whether the female will leave the nest at the same time as the fledgling young bird or whether she will fly out of the nest box beforehand.

literature

  • Mark Cocker, David Tipling: Birds and People. Jonathan Cape, London 2013, ISBN 978-0-2240-8174-0 .
  • W. Grummt , H. Strehlow (Ed.): Zoo animal keeping birds. Verlag Harri Deutsch, Frankfurt am Main 2009, ISBN 978-3-8171-1636-2 .
  • Alan Kemp: The Hornbills - Bucerotiformes. Oxford University Press, Oxford 1995, ISBN 0-19-857729-X .
  • Ian Sinclair: Birds of Africa South of the Sahara: A Comprehensive Illustrated Field Guide. Struik Publishers, ISBN 1868728579 .

Web links

Single receipts

  1. ↑ Bycanistes cylindricus in the endangered Red List species the IUCN 2016 Posted by: BirdLife International, 2016. Retrieved on 7 December 2016th
  2. ↑ a b c Kemp: The Hornbills - Bucerotiformes . P. 249.
  3. ↑ Kemp: The Hornbills - Bucerotiformes . P. 250.
  4. ↑ a b Kemp: The Hornbills - Bucerotiformes . P. 251.