Black-eared bowerbird
| Black-eared bowerbird | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
.jpg)
Black-eared bowerbird, Lake Eacham , Queensland |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Ailuroedus melanotis | ||||||||||||
| ( GR Gray , 1858) |
The black-eared bowerbird ( Ailuroedus melanotis ) is a species from the family of bowerbirds (Ptilonorhynchidae) and is a representative of both the avifauna of Australia and New Guinea. Aside from the brown-bellied bowerbird , the black-eared bowerbird is the only bowerbird found on both the Australian continent and New Guinea. Compared to the closely related gardener birds that occur exclusively in New Guinea, this species of bowerbird has been well researched due to its distribution area in Australia. There are ten subspecies for this species in the large distribution area.
With a body length of up to 29 centimeters, the black-eared bower bird is one of the medium-sized representatives in the bower bird family. It is one of the species whose courtship behavior does not include the construction of an arbor by the male. They are monogamous and have a relationship of several years. Both sexes defend a territory all year round.
Black-eared bowerbirds are very long-lived and take several years to reach sexual maturity. On the basis of ringing data it is known that they can reach an age of at least 19 years. According to the IUCN, their stock situation is classified as safe ( least concern ).
features
The males of the black-eared bowerbird reach a body length of up to 29 centimeters, of which 11.1 to 12.5 centimeters are on the tail in the nominate form . The females are the same size. With them 12 to 12.2 centimeters are allotted to the tail plumage. The beak length is 3.3 to 3.8 centimeters in both sexes. They weigh between 196 and 285 grams. There is no noticeable gender dimorphism .
Black-eared bowerbirds are matt black from top to neck to large pale with dark reddish-brown feathers, some of which are partially washed over with green. The top of the head looks spotted. The speckle is larger and sparse on the head, but dense and small on the nape. The eponymous ear covers are matt black and are surrounded by whitish to isabel-colored plumage at the top and the front below. The chin is matt black, the throat is dirty white to pale isabel with dark gray feather ends. The back and rump are emerald green to grass green, the tail plumage is emerald green, with the exception of the middle pair of control feathers, all control feathers have white feather tips. The inner arm wings and parts of the wing cover have pale isabel-colored to white feather ends. The wrist wings, on the other hand, are brown-gray with greenish or bluish feather edges.
The front breast is matt isabel-colored and slightly washed over with green, the black-eared bowerbird looks scaled through the brown-black feather edges. This is less pronounced on the rest of the underside of the body. The under tail-coverts show a fuzzy gray transverse banding. In some individuals, this is also limited to two wider transverse ligaments.
The beak is pale gray to creamy white, the legs and feet are blue-gray.
Young birds are similar to adult birds, but they are more finely drawn on the neck. The throat is whiter than that of the adult birds.
voice
The characteristic call of the black-eared bowerbird is a cat-like meow. These sounds are typical for all species of the genus Ailuroedus and have led to the English name Catbirds (German cat birds). Males tend to call louder than females.
In addition to the typical meowing calls, there are sharp, high-pitched contact sounds between the birds in a couple or a family group. The intensity of both the contact sounds and the meowing call increases in September, with the start of the courtship phase.
distribution and habitat
The black-eared bowerbird occurs in both Australia and New Guinea. In New Guinea it populates forests of foothills and low mountain ranges at altitudes between 600 and 1700 meters above sea level. In Australia, its distribution area extends over the tropical northeastern Queensland. It occurs there from the Cape York Peninsula to Mount Halifax in the Paluma Range . The distribution area in Australia, however, is disjunct as in New Guinea . The altitude distribution in Australia ranges from the lowlands to altitudes of 1540 meters. However, it is most common between 600 and 900 meters above sea level.
It inhabits all forest levels in the tropical rainforests of its distribution area and is only absent in the upper treetop area. In contrast, it can be observed very often on the ground.
The individual subspecies can be found in the following regions:
- At the. misoliensis Mayr & Meyer de Schauensee, 1939 - The island of Misool , which, with an area of around 2000 km², is one of the four main islands of the Raja Ampat archipelago off the coast of western New Guinea ( Indonesia ).
- At the. arfakianus AB Meyer, 1874 - Vogelkop Mountains , Fakfak Mountains of the Onin peninsulas and the Wandammen Mountains
- At the. jobiensis Rothschild, 1895 - Foja Mountains , Bewani Mountains , Torricelli Mountains , Prince Alexander Mountains in northern New Guinea.
- At the. facialis Mayr, 1936 - Nassau Mountains and Oranje Mountains in western New Guinea.
- At the. guttaticollis Stresemann, 1922 - Hunstein Mountains, Sepik Mountains and Jimi Mountains in northeast New Guinea.
- At the. astigmaticus Mayr, 1931 - Mountains of the Huon Peninsula in northeast New Guinea
- At the. melanotis (GR Gray, 1858) - Aru Islands and the Trans Fly with Wasur Rawa Biru National Park
- At the. melanocephalus EP Ramsay, 1883 - Mountains in southeast New Guinea.
- At the. joanae Mathews, 1941 - East of the Australian Cape York Peninsula to the McIlwraith Range, Queensland, Eastern Australia.
- At the. maculosus EP Ramsay, 1875 - Tropics in northeast Queensland from the Atherton Tableland to the Seaview Range , Queensland, Eastern Australia.
General way of life and food
The black-eared bower bird is a shy, secretive bird that lives solitary, in pairs or in small family groups. It is an omnivore, but mainly eats fruits and occasionally flowers, buds, leaves, plant stems and animal food. The food habits of the populations in New Guinea have not been very well studied, but according to the current state of knowledge they mainly cover their food needs with stone fruits , berries and wild figs. During his 1972 expedition, Jared Diamond discovered that they were also killing smaller birds and bats that he had caught in Japanese nets for research purposes. In fruit-bearing trees, however, black-eared bowerbirds are displaced by both the Indian Koel and the red-brown Reinwardt pigeon .
The food habits of the Australian populations are better studied. We know from data from individual studies that they rarely look for food in small groups, but are mostly solitary in search of food. Only in very large fruit-bearing trees can three or four black-eared bowerbirds be found together. In the Paluma Range they covered 73 percent of their nutritional needs with ten plant species.
.jpg)
In larger fruit-bearing trees, mostly fig species, they are occasionally with dental Laubenvogel , columns gardener , silk Laubenvogel , Pink breast cuckoo dove , stripes tracked catcher ( Coracina lineata ), long-tailed pigeon and Viktoria Bird of Paradise socialized. Black-eared bowerbirds can displace tooth-bowerbirds and silky-bowerbirds in such trees, whereas long-tailed fruit pigeons are more assertive against black-eared bowerbirds.
Smaller fruits are picked from the branches and eaten whole. Larger fruits either directly on site or on a neighboring branch with the beak divided into smaller pieces. Occasionally they also hoard fruit, mostly in the crown of epiphytic tree ferns.
Black-eared bowerbirds in the Paluma Range covered around six percent of their food requirements with animal food. Mostly they are worms, cockroaches, termites, singing cicadas, beetles, caterpillars and spiders. The invertebrates are usually pecked from leaves, twigs and tree trunks or found in the layer of leaves lying on the ground. But they are also able to catch insects in flight. They also eat the eggs and nestlings of other bird species. A nestling of the fern flycatcher was killed despite strong resistance from the parent birds. They are also the only diurnal predators of young birds of the black- headed fluteer ( Orthonyx spaldingii ) and presumably they also eat the eggs or kill the young birds of the gnarled bird and column gardener.
Reproduction
Unlike other bowerbirds, the male black-eared bowerbird does not build arbors. They are monogamous birds that enter into a partnership of several years and together defend a feeding and breeding ground. On the basis of ringed birds, it was possible to prove that a pair occupied a territory for several years. It consists of a slightly larger feeding area and a slightly smaller breeding area within it. The breeding area is newly established at the beginning of the breeding season, but it has been proven that individual birds or pairs use the same breeding area for several years. The breeding area has a size of 1.6 hectares. The courtship is not very elaborate: Clifford and Dawn Frith write about their courtship in their monograph: Courtship involes little more than the pair Shopping excitedly about tree Peches - the courtship is little more than an excited hopping of the couple in the branches. However, the male usually offers food to the female before mating.
Black-eared bowerbirds also show a high level of loyalty to their nesting place. A female used the same nesting site for ten consecutive breeding seasons. The new nests are usually only a few meters away from the old nest. Often the new nest is also built directly on top of the old nest. If the first clutch is lost to predators, for example, a second clutch occurs, but the couple then builds the nest at an average distance of 37 meters from the old nest. In two observed couples who lost their first clutch, the replacement nest was built within 16 days and a first egg was laid.
The clutch usually consists of one to three eggs, but in the majority a clutch only comprises two eggs. The laying interval is one day. The full freshness weight is 18.7 grams. It only breeds the female, she starts breeding as soon as the clutch is complete. The breeding season is 22 to 23 days. The nestlings are also exclusively hoed by the female. The nestlings fledge after about 19 to 20 days.
Black-eared bowerbirds and humans
London Zoo held three black-eared bowerbirds ready in 1908. In Australia and Singapore, this species is often kept by private individuals. From captivity it is also reported that green -arborebirds can be crossed with black-eared bowerbirds, but there are no scientific reports about this.
literature
- Clifford B. Frith, Dawn. W. Frith: The Bowerbirds - Ptilonorhynchidae . Oxford University Press, Oxford 2004, ISBN 0-19-854844-3 .
- Mike Hansell: Bird nests and construction behavior , illustrated by Raith Overhill, Cambridge University Press, ISBN 0521017645 .
- Peter Rowland: Bowerbirds . Csiro Publishing, Collingwood 2008, ISBN 978-0-643-09420-8 .
Web links
Single receipts
- ↑ a b c d Handbook of the Birds of the World zum Schwarzohr-Laubenvogel , accessed on April 25, 2017
- ↑ Rowland: Bowerbirds . P. 101.
- ↑ a b c d e f Frith: The Bowerbirds - Ptilonorhynchidae . P. 242.
- ↑ a b Frith: The Bowerbirds - Ptilonorhynchidae . P. 248.
- ↑ Frith: The Bowerbirds - Ptilonorhynchidae . P. 234.
- ↑ Frith: The Bowerbirds - Ptilonorhynchidae . P. 233.
- ↑ a b Frith: The Bowerbirds - Ptilonorhynchidae . P. 241.
- ↑ a b c Frith: The Bowerbirds - Ptilonorhynchidae . P. 238.
- ↑ a b c Frith: The Bowerbirds - Ptilonorhynchidae . P. 239.
- ↑ Frith: The Bowerbirds - Ptilonorhynchidae . P. 240.
- ↑ a b c Frith: The Bowerbirds - Ptilonorhynchidae . P. 245.
- ↑ Frith: The Bowerbirds - Ptilonorhynchidae . P. 249.