Austen hornbill

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Austen hornbill
Austen hornbill

Austen hornbill

Systematics
Class : Birds (aves)
Order : Hornbills and hops (Bucerotiformes)
Family : Hornbills (Bucerotidae)
Genre : Anorrhinus
Type : Austen hornbill
Scientific name
Anorrhinus austeni
Jerdon , 1872

The Austen hornbill ( Anorrhinus austenitic ) is an Asian bird art that the hornbills belongs (Bucerotidae). The species is monotypical , the tickell hornbill , which was once considered a subspecies of the austenhorn bird , is now granted its own species status.

Like all hornbills, the austen hornbill is also a cave breeder. For the duration of the breeding season, the female walled herself up in a tree cavity and only left a narrow gap open. The male supplies them and later the young birds with food through this gap. One of the special features of the austenhorn bird is that it raises its offspring with helpers. The male is assisted by other males in caring for females and young birds.

The stock situation of Austen Horn bird is on the IUCN threatened with potentially ( near threatened ) classified.

features

The austen hornbill reaches a body length of 60 to 65 centimeters. The males have an average of 29.5 centimeters and the females 26.5 centimeters. The beak measures 11.2 to 13.5 centimeters in the males. The female's beak is smaller, measuring between 10.5 and 11.7 centimeters.

Appearance of the males

The male is dark brown on the upper side of the body. The underside of the body is reddish brown, only the cheeks and throat are white. The wings are dark brown, the arm wings have white tips and white spots on the outer flags. The tail is dark brown. Except for the middle pair of tail feathers, the tail feathers all have white tips. The beak and the low ridge of the beak are ivory white with an orange tint at the base of the beak. The featherless skin around the eyes and the bare throat patch are light blue to bright blue. The eyes are brown, the legs and feet are dull greenish-brown.

Appearance of females and fledglings

The gender dimorphism is not very pronounced. The females correspond to the males in terms of plumage. However, they are a bit smaller. The cheeks, throat and underside of the body are gray-brown. The featherless skin of the face is pink with a yellow tint below the eye.

Fledglings are initially colored like the adult males, but the underside of the body is paler and the neck, elytra and wings have broad pale brown feather tips. The beak is pale yellow to horn-colored. The feathered skin on the face is yellowish. The eyes are gray-brown, the legs and feet are brown.

Young female birds molt into the plumage of adult females when they are one year old. The beak is then yellowish-ivory in color with a greenish tinge at the base of the beak.

Distribution area and habitat

The austen hornbill occurs in the extreme northeast of India as well as Myanmar, in the Chinese province of Yunnan, in Thailand, Vietnam and Laos.

The austen hornbill is preferred in dense evergreen rainforests from the lowlands to altitudes of up to 1500 meters. In contrast, it is rare in hardwood forests.

Way of life

The austen hornbill is a territorial bird that defends a territory either as a pair or as a troop consisting of five to 15 individuals. Individuals in a squad keep in contact with one another by loud calls or - while eating - by soft cackling noises. It can often be seen near oriental hornbills or other fruit-eating birds in the tops of tree tops. Basically, its behavior is restless: it constantly changes from one branch to another or flies to another tree. The austen hornbill rarely comes to the ground.

The austen hornbill, like all hornbills, is omnivorous. Plant-based foods and animal protein play a similar role in his diet. Wild figs account for around 22 percent of the vegetable diet. In total, it eats the fruits of 32 plant species from 15 different families. The fruits of olive willow , Elaeocarpus , Cinnamomum , Litsea , Aglaia , Oplopanax and cherry myrtle are eaten . The animals it eats include bats, reptiles, mussels and various arthropods . In addition, there are young birds and eggs of various bird species such as pigeons and bulbuls .

Reproduction

Austen hornbills are monogamous. In 22 breeding pairs examined in more detail, 18 pairs had support from one to five other hornbills helping. In all cases the males were of different ages. In principle, more young birds hatch from breeding caves in which the breeding pair receives support from several helpers than was the case with breeding caves with no or only a few brooders. The greater success in breeding is not necessarily due to more food that is brought to the nest cavity, but to a more successful defense against nesting competitors and predators.

The breeding season is estimated to be 92 days in total. Of this, 30 days are spent on incubating the eggs and 62 days on the nestling period. The clutch contains 2 to 3 eggs. Larger clutches occur, but are rare. Tree hollows are used. These are usually natural tree hollows. Austenhorn birds, however, occasionally use tree hollows made by the powder woodpecker. Tree hollows are used for several years and vigorously defended against other hornbill species and conspecifics. Individual tree hollows were also used alternately by the austen hornbill, the furrow hornbill and the oriental hornbill .

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 .
  • Gordon Lindsay Maclean: Robert's Birds of South Africa . 6th Edition, ISBN 0620175834 .

Web links

Commons : Hornbill  - Collection of images, videos and audio files

Single receipts

  1. ↑ a b Kemp: The Hornbills - Bucerotiformes . P. 101.
  2. ↑ a b c d e Kemp: The Hornbills - Bucerotiformes . P. 103.
  3. ↑ Anorrhinus austeni in the IUCN Red List of Threatened Species 2016.1. Posted by: BirdLife International, 2016. Retrieved December 25, 2016.
  4. ↑ Kemp: The Hornbills - Bucerotiformes . P. 102.
  5. ↑ a b Kemp: The Hornbills - Bucerotiformes . P. 104.