Eastern yellow-beaked Toko
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Eastern Yellow-billed Toko ( Tockus flavirostris ), Kenya |
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| ( Rüppell , 1835) |
The Eastern Yellow-billed Hornbill ( Tockus flavirostris ) is a bird art that the hornbills belongs (Bucerotidae) and in the eastern sub-Saharan Africa occur. Like all species of the genus Tokos it is a cave breeder. The female walled herself up in a tree cavity during the breeding season and, like the nestlings later, was provided with food by the male.
Due to the large distribution area and the frequency of the species, the stock situation of the Eastern Yellow-Beaked Tokos was classified in the IUCN Red List of Threatened Species as " Least Concern (LC) " = "not endangered".
features
The Eastern Yellow-Beaked Toko is a medium-sized Toko with a body length of up to 40 centimeters. The male's beak is 7.9 to 9.4 centimeters. The beak in the females is slightly smaller and measures between 6.2 and 8 centimeters. The larger males weigh between 225 and 275 grams, the females weigh between 170 and 191 grams. A sexual dimorphism is otherwise scarce.
male
The males have a black crown and a black neck. A wide white stripe runs from the forehead over the eyes to the nape of the neck. The back is black with a wide white line in the middle of the back. The middle four of the ten control springs are completely black. The rest of them are black and then white with a wide black stripe in the middle. The throat and underside of the body are white. The arm wings are black with a white spot in the middle that gets bigger and bigger in the direction of the arm wings. The middle arm wings are white with a black tip. The upper wing-coverts are soot-brown with large white spots. On the upper beak there is a beak ridge over the entire length. The beak is yellow and turns orange at the base of the beak. The tip of the beak and the sheaths are black. The featherless orbital ring is black while the bare throat patch is flesh-colored pink. The eyes are yellow, the legs and feet are dark gray-brown.
Females and young birds
The female resembles the male in their body plumage, but is slightly smaller. In contrast to the male, the bare throat skin is black, the ridge of the beak ends on half of the upper beak.
Young birds are similar to adult birds. However, their beak is even smaller and uniformly pale yellow with some light gray spots. The front chest is dashed dark gray and the eyes are dull gray.
voice
The characteristic calls of the eastern yellow-billed coconut are deep cackling, which are often called in a series of Kok-kok-kok-kok-kok-korkorkorkorkor . The calls are significantly deeper than those of the southern yellow-billed coconut.
Possible confusion
The southern yellow-billed toko occurs in West Africa, the range of the two species does not overlap. The most noticeable difference between the two types is the different coloring of the orbital ring. It is strong flesh-colored in both sexes in the southern yellow-beaked toko.
In the distribution area of the Eastern Yellow-billed Toko, the Blanket Toko has a similar body plumage. However, it lacks the white spots on the wings. However, the two types can be most clearly distinguished by their different beak colors. In the blanket toko, the males have beaks that are orange and creamy white. The females, on the other hand, have black beaks.
The Rotschnabeltoko , which also has a distribution area that overlaps with the Eastern Yellow Beaked Toko, is up to 35 centimeters in length, has a bright red bill and less noticeable white spots on the wings.
distribution and habitat
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The Eastern Yellow-billed Toko is found in eastern Africa in Eritrea , Somalia , Ethiopia , the southeast of Sudan, Kenya and northern Tanzania . It lives in tree and thorn bush savannahs and dry acacia and mopane forests .
It is not a common bird in its entire range. It occurs most frequently in open thorn bush savannahs and open forest landscapes. It is basically a resident bird, but occasionally undertakes seasonal high-altitude hikes, during which it changes from the arid lowlands to higher altitudes in the dry season.
food
The diet consists of insects , scorpions , rodents , fruits and seeds. The Eastern Yellow-billed Toko finds most of its food on the ground or pecks it from low vegetation. According to a study from 1985, it covers 97 percent of its nutritional needs. With fast runs and flat jumps, they chase after small reptiles and grasshoppers or prey on termites swarming in flight . He has also been seen digging for beetle larvae in rotten tree stumps. He is also reported to have been drinking regularly, which is unusual behavior for hornbills.
The Eastern Yellow-billed Toko cooperates with a subspecies of the Southern Pygmy mongoose ( Helogale parvula undulata ) in foraging for food . It catches the insects (especially grasshoppers) that scare away this group of predators as they forage. The pygmy mongooses benefit from this protocooperation because the Eastern Yellow-Beaked Toko warns of predators from the air. The dwarf mongooses wait for the toko to begin their prey. The Eastern Yellow-Beaked Toko also shows specific behaviors to indicate to the dwarf mongoose that it is willing to cooperate. A similar behavior is also described for the ceiling toko.
behavior
The breeding biology of the Eastern Yellow-billed Toko has not yet been conclusively investigated. However, they are monogamous birds and defend a territory. The breeding season in Somalia falls from April to May, in Ethiopia they breed from March to May and possibly also from October to November.
As a breeding cave they use natural tree caves, especially in acacia trees , the breeding cave is usually 1.5 to 4.5 above the ground. The female seals the entrance to the breeding cave from the inside except for a narrow slit. She goes through the moulting during the breeding season.
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
- Tockus flavirostris in the endangered Red List species the IUCN 2012. Posted by: BirdLife International, 2012. Retrieved on 4 October 2016th
- Videos, photos and sound recordings of Tockus flavorists in the Internet Bird Collection
- Voice of the Eastern Yellow-Beaked Toko
Individual evidence
- ↑ Tockus flavirostris in the endangered Red List species the IUCN 2016 Posted by: BirdLife International, 2016. Accessed January 29, 2018th
- ↑ a b Kemp: The Hornbills - Bucerotiformes . P. 140.
- ^ Voice of the Eastern Yellow-Beaked Toko , accessed October 4, 2016
- ↑ Calls of the southern yellow-billed coconut on Xeno-Canto , accessed on October 3, 2016
- ↑ Kemp: The Hornbills - Bucerotiformes . P. 132.
- ↑ a b c Kemp: The Hornbills - Bucerotiformes . P. 141.
- ↑ a b Kemp: The Hornbills - Bucerotiformes . P. 142.
- ↑ Kemp: The Hornbills - Bucerotiformes . P. 143.