Long-headed hornbill
| Long-headed hornbill | ||||||||||
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Long-headed hornbill |
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| Systematics | ||||||||||
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| Scientific name of the genus | ||||||||||
| Berenicornis | ||||||||||
| Bonaparte , 1850 | ||||||||||
| Scientific name of the species | ||||||||||
| Berenicornis comatus | ||||||||||
| ( Raffles , 1822) |
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The long- crested hornbill ( Berenicornis comatus ) is a species of bird in the hornbill family that is found in Southeast Asia.
The stock situation of the long-crested hornbill was classified in the IUCN Red List of Threatened Species in 2016 as " Vulnerable (VU) ".
Appearance
The long-crested hornbill is a large hornbill with a body length between 75 and 80 centimeters. The male's tail accounts for an average of 42.6 centimeters, while the female's tail is slightly smaller at 41.7 centimeters. The beak of the male is on average 16.5 centimeters long, that of the female is slightly shorter with an average of 14.8 centimeters. The sex dimorphism in this species is so pronounced that the sexes can also be differentiated during field observation.
Appearance of the male
The head, neck, chest, tail and tips of the wings are white. The back, the wings, the thighs, the belly and the under tail-coverts are black. The plumage on the top of the body has a metallic green sheen. The feathers of the apex are extended to form a spring bonnet. The control springs are stepped. The beak and the low ridge of the beak are blackish with a greenish-yellow beak base. The bare skin around the eye and the bare throat patch are dull blue. The eyes are pale yellow, the legs and feet are black.
Features of the female and young birds
The adult females have a body plumage that is largely similar to that of the males. In females, however, only the bonnet is white and in many individuals the bonnet also has black spring shafts. The cheeks, neck and underside of the body are black.
In the young birds, both sexes initially show a body plumage that is not like any of the adult birds. The head, neck and underside of the body are black, many of the feathers have a white tip, which gives the young birds a piebald appearance. The tail feathers are black with pronounced white tips, the beak is yellow. The bare skin of the face is gray with a turquoise tone. The eyes are green-yellow, the legs and feet are gray.
In subadult long-headed hornbills, the males have a pure white feather bonnet. The subadult females have black feather shafts in the feather bonnet and have a greater proportion of white on the control feathers.
Distribution area and habitat
The range of the long-headed hornbill stretches from Myanmar across southwest Thailand , the Malay Peninsula , Sumatra and Borneo .
The long-crested hornbill is preferred in evergreen primary forest at altitudes of up to 900 meters. It is also very rarely found at altitudes of up to 1680 meters. In the forests of the lowlands it prefers to stay in forest areas with dense climbing vegetation. It also occurs along watercourses, at forest edges and also in selectively cut forest areas. Where oil palm plantations is directly adjacent to the forest, it occurs even in such plantations.
The long-crested hornbill can get by with small patches of primary forest if it is surrounded by secondary forest.
Way of life
The long-headed hornbill is a resident bird that lives in troops that defend a territory together. These flocks usually consist of three to eight individuals, which is a pair with one to three helpers and a few juveniles. Occasionally, groups that are significantly larger are also observed. According to Alan Kemp, these are either groups that meet in a territorial dispute or a chance meeting of groups in a particularly rich fruit-bearing tree. Both the couple and the helpers call out to indicate the area and also defend the area boundaries. The hornbills adopt a threatening posture by turning against the intruder, opening their wings, stretching the control feathers and lowering their beak. The groups are particularly large when there is plenty of fruit.
Unlike many other large hornbills, the flight of the long-headed hornbill is barely audible. The troops keep in contact with one another with low chuckling noises reminiscent of chickens. As far as we know, long-crested hornbills have resting trees to which they regularly return.
food
Long-crested hornbills use the entire forest area to forage. If they can also be found in the uppermost area of the top of the forest giants, they find a large part of their food in the lower area of the top or on the ground. While foraging for food, they poke between epiphytes, tear bark from trees or open capsule fruits. They have also been seen catching slow-flying salangans in flight.
Animal protein plays an important role in the diet of long-headed hornbills. They eat arthropods and small vertebrates, including snakes, lizards, and small birds. But they also eat fruit. Figs do not seem to play as much of a role in their diet as other hornbills do.
Reproduction
Long-crested hornbills are monogamous birds. It breeds the dominant pair, which is supported by the helpers in a cooperative breeding system. Very little is known about reproductive biology. Like all hornbills, long-headed hornbills are also cave-breeders. They use natural tree hollows. Only one young bird is raised by the group. It is still being fed by the parent birds or the helpers six months after it fledged.
Systematics
The long-headed hornbill was originally classified in the genus Aceros . It is now placed in the monotypical genus Berenicornis. It shares sexual dimorphism with the genus Aceros , but the control feathers are long and stepped, so the bonnet is not found in other species of the genus Acres . The bare skin of the face is not very extensive, the throat pouch is not inflatable. In addition, the young birds have a significantly different plumage than the adult birds.
Long-crested hornbill and human
The long-crested hornbill is an important omen for the Kayan people of Borneo.
literature
- 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 .
Web links
- Berenicornis comatus in the endangered Red List species the IUCN 2012. Posted by: BirdLife International, 2012. Accessed November 19, 2016th
- Calls of the long-headed hornbill on Xeno-Canto
Single receipts
- ↑ a b Berenicornis comatus in the endangered Red List species the IUCN 2016 Posted by: BirdLife International, 2016. Retrieved on 3 October 2017th
- ↑ a b c Kemp: The Hornbills - Bucerotiformes . P. 210.
- ↑ a b Kemp: The Hornbills - Bucerotiformes . P. 211.
- ↑ a b Kemp: The Hornbills - Bucerotiformes . P. 212.
- ↑ Kemp: The Hornbills - Bucerotiformes . P. 209.