Blue toucans
| Blue toucans | ||||||||
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Black- billed toucan ( Andigena nigrirostris ) |
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| Systematics | ||||||||
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| Scientific name | ||||||||
| Andigena | ||||||||
| Gould , 1850 |
The blue toucans ( Andigena ) are a genus of birds from the toucan family. It includes four species with comparatively small distribution areas within South America.
Appearance
Blue toucans reach a body size of 43 to 50 centimeters. The smallest species of the genus is the blue toucan with a body size between 43 and 48 centimeters, the largest is the black- billed toucan , which grows between 46 and 50 centimeters. The birds have a partially blue or blue-gray body plumage. This is brightest in the black- billed toucan , in the black-headed toucan and in the blue toucan it is darkest. On the upper side of the body, all four types have olive brown, gray or black color components. All species have red under tail coverts and are brown in color. None of the species shows any conspicuous sexual dimorphism ; Females tend to have a slightly shorter beak. As characteristic of toucans, they have long beaks; the longest beak is 9.2 to 11.2 cm in length from the black-billed toucan males. The females of this species have a beak length of 7.2 to 9.3 centimeters. The beaks are sometimes very colorful, only the nominate form of the black-billed toucan has a completely black beak.
distribution and habitat
All four species colonize mountain rainforests and cloud forests in the Andean region from Venezuela to Bolivia . The black-billed toucan, which occurs in Venezuela, Colombia and Ecuador, has the largest range . The smallest and most southerly distribution area has the black-headed toucan , which occurs only in a narrow strip of the Andean mountain region from the extreme south-east of Peru to the north-west of Bolivia.
The height distribution of the species is between 1,600 and 3,300 meters above sea level.
Way of life
Relatively little is known about the way of life of the blue toucans.
Knowledge about the black-headed toucan is limited to the fact that, as a rule, single birds, pairs or small family groups with up to four individuals are observed and the species mainly feeds on fruits.
All that is known about the black-billed toucan is that it predominantly resides in treetops and that the blue toucan typically occupies its ecological niche in large parts of the distribution area above 2,500 meters. Black-billed toucans are only sporadically observed up to an altitude of 3,200 meters. Almost nothing is known about their reproductive biology. In Colombia, black-billed toucans were observed in breeding condition in March and young birds were seen in July.
Like the other three species, the blue toucan is mostly found in tree tops; occasionally it comes close to the ground to look for berries. While foraging it is sometimes also associated with mountain kassiks ( Cacicus leucoramphus ), blue-backed mountain tangs ( Buthraupis montana ) and giant thrushes ( Turdus fuscater ). The posture of the blue toucans while foraging is typically very upright. The diet consists mainly of fruits; Animal nutrition probably plays a role during the rearing of nestlings. No research results are available on the reproductive behavior. The breeding season in Colombia probably falls between January and February. In Peru, young birds that had just flown out were observed in November.
The inguinal-billed toucan is currently the best-researched species. It is also observed in small groups of three to six individuals. About 45 days before the start of the breeding season, these troops disband. Fruits are the main food of the inguinal toucans, but the nestlings are also fed with bird eggs, insects, snails and mice. The mating gestures include the mutual offering of food; the few copulations that were observed in the field took place after the feed was handed over. The clutch consists of two to three eggs, which are laid in the driest season. This varies with the geographical latitude of its occurrence. The nestlings are naked, pink and blind immediately after hatching. You have noticeable calluses. The eyes only open on the 28th day, the nestlings fledge at 46 to 60 days. One or two young birds fly out per clutch.
attitude
The inguinal toucan is the only species of the genus blue toucans that is occasionally shown in zoological gardens and bird parks. At the beginning of the 21st century there were four zoological gardens in Europe that kept this species, including the Walsrode World Bird Park . In Europe the species was not bred until the beginning of the 21st century, the world first breed was achieved in 1974 by the Los Angeles Zoo.
species
The following species belong to the blue toucans:
- Inguinal toucan ( A. laminirostris )
- Blue toucan ( A. hypoglauca )
- Black-headed toucan ( A. cucullata )
- Black- billed toucan ( A. nigrirostris )
supporting documents
literature
- Werner Lantermann: Toucans and Arassaris. Filander Verlag, Fürth 2002, ISBN 3-930831-46-5
- Lester L. Short and Jennifer FM Horne: Toucans, Barbets and Honeyguides - Ramphastidae, Capitonidae and Indicatoridae . Oxford University Press, Oxford 2001, ISBN 0-19-854666-1
