African Black Swift

Kapsegler (Apus barbatus)

The Kapsegler (Apus barbatus ) is a species of bird in the family of sailors ( Apodidae ). The style is typical of the large Apus species and is similar in shape to the strong Pallid Swift and its closely related species. Within this relationship the Kapsegler has the darkest plumage coloration. The fragmented distribution area is also located in sub-Saharan Africa, mainly in eastern and southern Africa, in Madagascar. It is very common, at least in parts of its range and is classified as unthreatened.

Description

The Kapsegler has a body length of 16 centimeters, the wing length is 172-186 mm, the weight is on average about 42 grams. The body is slightly more massive as the pallid compared to frequent in Central Europe swifts, the wings are less pointed.

The bottom of the Kapseglers is black, except for the almost triangular, whitish throat patch, which can be individually different sizes. The surrounding almost black feathers enhance the contrast, but the throat patch is not always obvious. The middle back is also almost black and shows a bluish tinge.

On the underside of the wing feathers is towards the body (proximal ) is lighter than the outside, especially the large coverts and secondaries are paler in color than the rest of the wing. This contrast is not as strong as the Brown sailors, the only similar species whose breeding range overlaps with that of the Kapseglers by far. The Kapsegler but is usually easy to distinguish from the brown sailors, because the bright throat patch of Kapseglers much clearer and plumage colouration of brown glider is brown instead of black.

Compared to the swifts, which coincides with the Kapsegler during the austral summer, in addition to the shape of the lighter underside of the inner wing is the best differentiator. In comparison to swifts, the contrast between inner and outer wings while Kapsegler is much clearer.

The most often -heard cry of Kapseglers is typical of the genus Apus, but it is significantly higher than that of the Common Swift and thus sounds like hissing.

Dissemination and hikes

The distribution area of Kapseglers is scattered across sub-Saharan Africa, mainly in eastern and southern Africa, also in Madagascar. A detailed documentation of the breeding habitat of this type is complicated by numerous Einzelsichtungen outside the known area as well. Due to confusion with other species Perhaps the breeding area is greater than previously known.

The westernmost occurrence of Kapseglers are in Sierra Leone, in northern Liberia, in southern Nigeria, Cameroon in the southwest, on Bioko, in the north- eastern Angola and in the central coast of Namibia. Maybe, but these are only " summering " birds in northern Liberia, however, the species is sedentary.

For example, at Mount Moroto - - In East Africa, the Kapsegler from eastern Uganda is east to Kenya and to the extreme northern Tanzania before. Another isolated occurrence is in the north- eastern Tanzania. Further west there is a smaller distribution area, which extends from the eastern Democratic Republic of the Congo to the south-west Uganda. In these three areas, the species is sedentary.

Another, larger area of ​​distribution extends from western Mozambique and southern Malawi and extends south-west to the east and north of Zimbabwe. Here are the birds to be found throughout the year. In contrast, the populations of South Africa leave in the winter in the southern hemisphere the breeding area. This area extends from the Transvaal over the provinces of KwaZulu -Natal, Eastern Cape to Cape Town in the Western Cape Province. There are other isolated occurrences between these African main areas, mainly in Zambia, Botswana and Zimbabwe, among others, near the Victoria Falls. In some of these areas is believed that this is coming from other areas of migratory birds, sometimes there are also breeding records. To the east of the African mainland of Kapsegler also comes still found in Madagascar, especially in the lowlands, in the Comoros.

Habitat

The Kapsegler is found mainly in damp mountain country, but is also found in adjacent areas such habitats, even at lower altitudes. In some areas, it occurs on the cliffs, for example in the vicinity of Cape Town. The breeding range is primarily in an altitude range 1600-2400 meters, including rare, but occasionally even at sea level. In the Comoros, we find the Kapsegler in all habitats of the island group.

Behavior and food acquisition

As the swifts is also the Kapsegler sociable. He is to be found in flocks of hundreds of individuals, but also sporadically. In other sailors species it forms mixed schools. When foraging it tends to lower air layers to hunt for insects than the Kaffirs or Alpine Swift, especially in bad weather. The Kapsegler chases through the forest canopy and also on a lower level beneath large trees when the forest is lighter. Beetles, ants and termites were detected as food components.

Reproduction

The breeding season is in the East African part of the range in cold, dry periods in the middle of the year or during the rainy season. In South Africa, the laying period extends from September to February, in Malawi and Zimbabwe from August to September and in Madagascar from November to March.

The Kapsegler is a colony breeders, there are common colonies with the Alpine Swift ( Tachymarptis melba ). In East Africa, the Kapsegler shows a preference for hollow trees, in particular the East African juniper (Juniperus procera) is preferred as a nesting site. In South Africa, there are also more recent observations, tree breeders, mainly incubates the way there, but in the rock walls - if these are not made of granite. In the area of Cape Town, there are situated directly on the sea breeding colonies, some are so close to the water that the breeding niches are temporarily wetted by spray.

As nesting material grass is mainly used, but also thistledown and springs. 's Own species and other species The nest is a shallow dish, it is glued with saliva and also fixed with saliva on the ground. The lower part of the nest looks messy, above it looks quite fine, but is still robust. The nest consists of one or two eggs with an average size of 25.9 x 16.8 millimeters.

Inventory and risk

The size of the distribution area is estimated at 600,000 km ². Numbers for worldwide inventory is not available. The species is classified as safely Overall, however, the frequency is regionally very different. For example, the Kapsegler in South Africa is often, however, the sightings of the species are extremely rare in West Africa. There are good deposits in the Comoros and Madagascar. In the East African parts of the distribution area of Kapsegler is far less frequent than in South Africa and only regional basis regularly encountered. Since in this part of the range, the species breeds mainly on trees, land clearing work here may diminish, especially as the birds continue to select large trees as nesting areas when the surrounding them and foraging preferred forest was cleared.

System

The Kapsegler belongs to pallidus super species. This support group is next to him nor the Pallid Swift, the Sokotrasegler and Damarasegler. In the figure are all very similar species of the group, but they differ in plumage coloration, although not significantly. Here, the plumage of people living in dry areas species tends to be brighter than that of occurring in wetlands.

There are nine subspecies distinguished, two of which - sladeniae and balstoni - are seen by some authors as a separate species. Three more to be questioned due to the small number of individuals studied by some authors.

• Apus barbatus barbatus ( Sclater, 1866): The nominate colonized South Africa and is migratory. The appearance corresponds to the above description.
• Apus barbatus glanvillei Benson, 1967: This subspecies is based only on two individuals studied from Rokupr in Sierra Leone. The representatives are slightly darker than the nominate form, but otherwise very similar.
• Apus barbatus sladeniae ( Ogilvie - Grant, 1904): This breed is very scattered in West Africa before. It is even darker than the nominate and whether or not colored as glanvillei, also in the area of the throat; the throat patch is missing some individuals. The enormous differences in size within this subspecies make valid but questionable.
• Apus barbatus serlei De Roo, 1970: The only sightings of this subspecies are from Bamenda in Cameroon. Their representatives are obviously darker than the nominate form, they lack the blue glow of the back plumage.
• Apus barbatus roehli Reichenow, 1906: This breed is widespread in East Africa. The representatives are smaller than the nominate form and the plumage is darker. The wing length ranges 164-176 mm.
• Apus barbatus hollidayi Benson and Irwin, 1960: This subspecies is restricted to the area around the Victoria Falls. The birds are paler than the nominate form, the back is colored as the elytra.
• Apus barbatus oreobates Brooke, 1970: Similar to roehli, but are slightly langflügeliger the representatives of this race. It occurs in Zimbabwe and Mozambique.
• Apus barbatus balstoni ( Bartlett, 1880): This subspecies occurring in Madagascar is also similar roehli, but is a little bit darker. Most obvious is the difference in the small coverts, which are just as dark as the primaries.
• Apus barbatus mayottensis ( Nicoll, 1906): The representatives of the Comoros resemble balstoni that plumage coloration is, however, a little brownish.