White-rumped Swift
Encyclopedia
The White-rumped Swift (Apus caffer) is a small swift
. Although this bird
is superficially similar to a House Martin
, it is completely unrelated to that passerine
species. The resemblances between the swallows and swifts are due to convergent evolution
reflecting similar life styles.
Swifts have very short legs that they use only for clinging to vertical surfaces. They never settle voluntarily on the ground, and spend most of their lives in the air, feeding on insect
s that they catch in their beaks. They drink on the wing.
White-rumped Swifts breed in much of sub-Saharan
Africa
, and have expanded into Morocco
and southern Spain
. The populations in Spain, Morocco and the south of Africa are migratory
, although their wintering grounds are not definitively known. Birds in tropical Africa are resident apart from seasonal movements.
This species appropriates the nests of little swifts
and those swallows which build retort-shaped nests. In Europe and north Africa, this usually means the Red-rumped Swallow
, but south of the Sahara other species like Wire-tailed Swallow
are also parasitised. The original owners of the nests are driven away, or the white-rumps settle in the nest and refuse to move. Once occupied, the nest is lined with feathers and saliva, and one or two eggs are laid.
The habitat of this species is dictated by that of its hosts, and is therefore normally man-made structures such as bridges and buildings.
This 14-15.5 cm long species has, like its relatives, a short forked tail and long swept-back wings that resemble a crescent or a boomerang
. It is entirely dark except for a pale throat patch and a narrow white rump. It is similar to the closely related Little Swift, but is slimmer, darker and has a more forked tail and a narrower white rump.
This is a quiet species compared to Little Swift, but a twittering trill is sometimes given.
Swift
The swifts are a family, Apodidae, of highly aerial birds. They are superficially similar to swallows, but are actually not closely related to passerine species at all; swifts are in the separate order Apodiformes, which they share with hummingbirds...
. Although this bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
is superficially similar to a House Martin
House Martin
The Common House Martin , sometimes called the Northern House Martin or, particularly in Europe, just House Martin, is a migratory passerine bird of the swallow family which breeds in Europe, north Africa and temperate Asia; and winters in sub-Saharan Africa and tropical Asia...
, it is completely unrelated to that passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
species. The resemblances between the swallows and swifts are due to convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
reflecting similar life styles.
Swifts have very short legs that they use only for clinging to vertical surfaces. They never settle voluntarily on the ground, and spend most of their lives in the air, feeding on insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s that they catch in their beaks. They drink on the wing.
White-rumped Swifts breed in much of sub-Saharan
Sahara
The Sahara is the world's second largest desert, after Antarctica. At over , it covers most of Northern Africa, making it almost as large as Europe or the United States. The Sahara stretches from the Red Sea, including parts of the Mediterranean coasts, to the outskirts of the Atlantic Ocean...
Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, and have expanded into Morocco
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...
and southern Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
. The populations in Spain, Morocco and the south of Africa are migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
, although their wintering grounds are not definitively known. Birds in tropical Africa are resident apart from seasonal movements.
This species appropriates the nests of little swifts
Little Swift
The Little Swift , is a small bird, superficially similar to a Barn Swallow or House Martin. It is, however, completely unrelated to those passerine species, since swifts are in the order Apodiformes. The resemblances between the groups are due to convergent evolution reflecting similar life styles...
and those swallows which build retort-shaped nests. In Europe and north Africa, this usually means the Red-rumped Swallow
Red-rumped Swallow
The Red-rumped Swallow is a small passerine bird in the swallow family. It breeds in open hilly country of temperate southern Europe and Asia from Portugal and Spain to Japan, India and tropical Africa. The Indian and African birds are resident, but European and other Asian birds are migratory...
, but south of the Sahara other species like Wire-tailed Swallow
Wire-tailed Swallow
The Wire-tailed Swallow is a small passerine bird in the swallow family. Swallows are somewhat similar in habits and appearance to other aerial insectivores, such as the related martins and the unrelated swifts ....
are also parasitised. The original owners of the nests are driven away, or the white-rumps settle in the nest and refuse to move. Once occupied, the nest is lined with feathers and saliva, and one or two eggs are laid.
The habitat of this species is dictated by that of its hosts, and is therefore normally man-made structures such as bridges and buildings.
This 14-15.5 cm long species has, like its relatives, a short forked tail and long swept-back wings that resemble a crescent or a boomerang
Boomerang
A boomerang is a flying tool with a curved shape used as a weapon or for sport.-Description:A boomerang is usually thought of as a wooden device, although historically boomerang-like devices have also been made from bones. Modern boomerangs used for sport are often made from carbon fibre-reinforced...
. It is entirely dark except for a pale throat patch and a narrow white rump. It is similar to the closely related Little Swift, but is slimmer, darker and has a more forked tail and a narrower white rump.
This is a quiet species compared to Little Swift, but a twittering trill is sometimes given.