Damara sailor
| Damara sailor | ||||||||||
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Damaras Swift ( Apus bradfieldi ) |
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| Systematics | ||||||||||
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| Scientific name | ||||||||||
| Apus bradfieldi | ||||||||||
| ( Roberts , 1926) |
The Damarasegler ( Apus bradfieldi ) is a species of the genus Apus in the family of the sailors that occurs only in southwestern Africa . The Damarasegler is similar to the Common Swift , but in contrast to this resident bird .
description
The Damarasegler with a body length of 18 centimeters is the palest representative of the fairly uniformly colored genus.
Both the upper and lower sides of the body are very evenly pale gray-brown in color, except for the broad, but indistinct cream-colored throat patch. The top of the body looks paler than the wing tips and tail. The underside is very pale but clearly drawn, the feathers have narrow but clear brown bands and white fringes. The markings are clearest on the chest and stomach.
The wing underside is typical of the genus Apus , the wing feathers and larger cover feathers are uniform and a little paler and greyish than the body. The pattern corresponds more to the pale swift than the common swift, as the middle arm covers are only slightly darker than the large arm covers and therefore the dark area is limited to the small cover feathers.
Both sexes look the same.
Differentiation of similar species
The pale swift comes closest to the damara swift, but so far it has almost never been found south of the equator, so that the common swift , which is also in the south-western part of Africa during the winter in the northern hemisphere, is the most difficult species to distinguish in practice should be. The damaras can probably best be distinguished by their pale, gray-brown body feathers, which show a clear drawing on the underside. The swift's smaller and rounded throat spot also stands out more clearly.
Spreading and migrations
The occurrence of the Damarasegler is limited to the southwest of Africa. In Namibia it can be found in the higher elevations, including the Skeleton Coast Park . In addition, it occurs in southern Namibia in the Fish River Canyon , the northwestern end of the range are the adjacent areas in southern Angola . Even South Africa includes the distribution area, in the area around Kimberley of Bradfield's Swift can be found, in some areas he comes here, together with the African Black Swift ago.
In areas with favorable conditions it is quite common, in the central areas of Namibia it is the most common breeding sailor. The Damara sailing ship is also relatively common in the South African province of the North Cape , breeding in two of the five big holes .
It is assumed that the damaraseglider is a resident bird in the entire distribution area , even if it shows a pronounced nomadic behavior in foraging after the breeding season.
literature
- Phil Chantler, Gerald Driessens: A Guide to the Swifts and Tree Swifts of the World . Pica Press, Mountfield 2000, ISBN 1-873403-83-6
Web links
- Apus bradfieldi in the endangered Red List species the IUCN 2008. Posted by: BirdLife International, 2008. Accessed on 12 November, 2008.