Brown-throated heron
| Brown-throated heron | ||||||||||||
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Black- throated heron ( Egretta vinaceigula ) |
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| Scientific name | ||||||||||||
| Egretta vinaceigula | ||||||||||||
| ( Sharpe , 1895) |
The brown-throated heron ( Egretta vinaceigula ) is a species of heron from the genus Egretta . It has an unusually small range and is only found in southern Central Africa. It is one of the least explored species of heron. For a long time it was thought to be a subspecies of the bell heron . However, it differs in its habitat requirements, its physique and its eating habits, so that today there is broad consensus to classify it as an independent species.
Appearance
The brown-throated heron reaches a body length of 43 centimeters and weighs between 250 and 340 grams. The basic color of the plumage is a dark blue-gray, which, however, can appear almost black when observed in the field. The beak is narrow and dark. The irises are yellowish. The throat and chin as well as the fore neck are reddish brown. At the back of the head there are elongated feathers that form a small gray tuft. Elongated feathers are also found on the lower neck as well as on the back. The underside of the wings is cream-colored to pale blue-gray. The legs are yellowish gray to yellowish green.
The brown-throated heron is very similar in appearance to the bell-shaped heron . However, it is built a little lighter. The most important distinguishing features are the red-brown throat and the yellow legs, both of which are missing in the bell heron.
Distribution area, population and habitat
The center of the range of the brown-throated heron is the Okavango Delta , which is located in the northwest of Botswana . This inland delta in the middle of the semi-arid Kalahari with an area of over 20,000 square kilometers is one of the largest and most animal-rich wetlands in Africa. The range of the brown-throated heron may extend to the Chobe River in Botswana and the Caprivi Strip in Namibia . There are isolated reports from other wetlands such as Zambia and Namibia as well as Angola . However, it is not known whether these are permanent resident breeding populations. The size of the population has only been sparsely investigated. There are probably fewer than 5,000 brown-throated herons.
The habitat of the brown-throated heron are seasonally flooded areas. He prefers to look for food in shallow water zones. He rarely goes to open water. He usually stays where higher vegetation offers him protection. Because of its specific habitat requirements and its small distribution area, it is considered a potentially endangered species. In particular, a change in its habitat can have strong effects. For example, brown-throated herons disappeared in previously populated areas after a river was dammed or reed belts burned down.
Way of life
The brown-throated heron looks for its food mainly in water zones with a water level of less than 10 centimeters. He moves in the manner typical of herons, walking slowly or standing still in one place for a long time. Relatively often he digs up the ground with his feet. The food spectrum includes snails, which it reads from water lily leaves, dragonflies, frogs, tadpoles and small, five to ten centimeters long fish. It is mostly diurnal with activity peaks at dusk. He spends his rest in trees or in the reed belt. It is often socialized with other herons and storks .
The breeding season begins after the peak of the floods. The nests are built in small colonies. It is often associated with the red-bellied heron. The clutch usually consists of three eggs. The breeding season is 21 to 24 days.
supporting documents
Single receipts
- ^ Kushlan et al., P. 159
- ↑ Kushlan et al., P. 160
- ↑ Kushlan et al., P. 160
- ↑ Kushlan et al., P. 161
- ↑ Kushlan et al., P. 161
literature
- James A. Kushlan & James A. Hancock: Herons . Oxford University Press, 2005, ISBN 0198549814
Web links
- Egretta vinaceigula onthe IUCN 2013 Red List of Threatened Species . Listed by: BirdLife International, 2013. Retrieved November 21, 2013.