Australian Swiftlet
Encyclopedia
The Australian Swiftlet (Aerodramus terraereginae) is a small bird
belonging to the genus Aerodramus
in the swift
family, Apodidae. It is endemic to Queensland
in north-eastern Australia
. It was formerly included in the White-rumped Swiftlet
(Aerodramus spodiopygius) but is now commonly treated as a separate species. It has two subspecies
which are occasionally regarded as two separate species: A. t. terraereginae and A. t. chillagoensis (Chillagoe Swiftlet).
It has a high-pitched flight call. In its breeding cave
s, it utters a metallic clicking call, used for echolocation
.
south as far as the Eungella Range near Mackay
. It is mainly found near the coast including a number of offshore islands. It occurs up to 1000 metres above sea-level but is commonest below 500 metres. A. t. chillagoensis is found further inland in the area around Chillagoe
, west of the Great Dividing Range
.
which can contain hundreds of individuals. These are located in caves or sometimes amongst boulders. The nest
is attached to the walls or ceiling of the cave, 2-20 metres above the ground. It is translucent and basket-shaped and made from saliva
mixed with grass
es, casuarina
needles, twigs and feathers. Two clutches
are laid during the breeding season, each consisting of a single white egg
. The egg is incubated
by both parents for about 26.5 days. Incubation of the second egg is aided by warmth from the first chick. The young bird remains in the nest for about 46-51 days after hatching.
The Australian Swiftlet feeds in flight, preying on insect
s and drifting spider
s. It forages in flocks over rainforest
edges, savanna
, pastures, beaches and gorges. It generally feeds within 30 kilometres of the breeding colony, leaving the nest for periods of about 30 minutes to hunt.
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...
belonging to the genus Aerodramus
Aerodramus
Aerodramus is a genus of small, dark, cave-nesting birds in the Collocaliini tribe of the swift family. Its members are confined to tropical and subtropical regions in southern Asia, Oceania and northeastern Australia...
in the swift
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...
family, Apodidae. It is endemic to Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
in north-eastern Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. It was formerly included in the White-rumped Swiftlet
White-rumped Swiftlet
The White-rumped Swiftlet is a species of swift in the Apodidae family.It is found in American Samoa, Fiji, New Caledonia, Papua New Guinea, Samoa, Solomon Islands, Tonga, and Vanuatu...
(Aerodramus spodiopygius) but is now commonly treated as a separate species. It has two subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
which are occasionally regarded as two separate species: A. t. terraereginae and A. t. chillagoensis (Chillagoe Swiftlet).
Description
It is 11-12 centimetres long with a wing length of 107-118.2 millimetres and a weight of 10.5-12.5 grams. The upperparts are dark grey-brown while the underparts are a uniform greyish. There are pale feathers on the forehead and lores. The rump is normally pale greyish but can occasionally be darker. The tail is slightly forked. The form chillagoensis is smaller and paler with a weight of around 9.39 grams.It has a high-pitched flight call. In its breeding cave
Cave
A cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...
s, it utters a metallic clicking call, used for echolocation
Animal echolocation
Echolocation, also called biosonar, is the biological sonar used by several kinds of animals.Echolocating animals emit calls out to the environment and listen to the echoes of those calls that return from various objects near them. They use these echoes to locate and identify the objects...
.
Distribution
A. t. terraereginae occurs in tropical north-east Queensland from the Claudie River on the Cape York PeninsulaCape York Peninsula
Cape York Peninsula is a large remote peninsula located in Far North Queensland at the tip of the state of Queensland, Australia, the largest unspoilt wilderness in northern Australia and one of the last remaining wilderness areas on Earth...
south as far as the Eungella Range near Mackay
Mackay, Queensland
Mackay is a city on the eastern coast of Queensland, Australia, about north of Brisbane, on the Pioneer River. Mackay is nicknamed the sugar capital of Australia because its region produces more than a third of Australia's cane sugar....
. It is mainly found near the coast including a number of offshore islands. It occurs up to 1000 metres above sea-level but is commonest below 500 metres. A. t. chillagoensis is found further inland in the area around Chillagoe
Chillagoe, Queensland
Chillagoe in northern Queensland, Australia, was once a thriving mining town for a range of minerals, but is now reduced to a small zinc mine and some marble quarries. At the 2006 census, Chillagoe had a population of 227....
, west of the Great Dividing Range
Great Dividing Range
The Great Dividing Range, or the Eastern Highlands, is Australia's most substantial mountain range and the third longest in the world. The range stretches more than 3,500 km from Dauan Island off the northeastern tip of Queensland, running the entire length of the eastern coastline through...
.
Ecology
Breeding occurs from July to March. The species breeds in coloniesBird colony
A bird colony is a large congregation of individuals of one or more species of bird that nest or roost in close proximity at a particular location. Many kinds of birds are known to congregate in groups of varying size; a congregation of nesting birds is called a breeding colony...
which can contain hundreds of individuals. These are located in caves or sometimes amongst boulders. The nest
Nest
A nest is a place of refuge to hold an animal's eggs or provide a place to live or raise offspring. They are usually made of some organic material such as twigs, grass, and leaves; or may simply be a depression in the ground, or a hole in a tree, rock or building...
is attached to the walls or ceiling of the cave, 2-20 metres above the ground. It is translucent and basket-shaped and made from saliva
Saliva
Saliva , referred to in various contexts as spit, spittle, drivel, drool, or slobber, is the watery substance produced in the mouths of humans and most other animals. Saliva is a component of oral fluid. In mammals, saliva is produced in and secreted from the three pairs of major salivary glands,...
mixed with grass
Grass
Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...
es, casuarina
Casuarina
Casuarina is a genus of 17 species in the family Casuarinaceae, native to Australasia, southeast Asia, and islands of the western Pacific Ocean. It was once treated as the sole genus in the family, but has been split into three genera .They are evergreen shrubs and trees growing to 35 m tall...
needles, twigs and feathers. Two clutches
Clutch (eggs)
A clutch of eggs refers to all the eggs produced by birds or reptiles, often at a single time, particularly those laid in a nest.In birds, destruction of a clutch by predators, , results in double-clutching...
are laid during the breeding season, each consisting of a single white egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
. The egg is incubated
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...
by both parents for about 26.5 days. Incubation of the second egg is aided by warmth from the first chick. The young bird remains in the nest for about 46-51 days after hatching.
The Australian Swiftlet feeds in flight, preying 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 and drifting spider
Spider
Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...
s. It forages in flocks over rainforest
Rainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
edges, savanna
Savanna
A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...
, pastures, beaches and gorges. It generally feeds within 30 kilometres of the breeding colony, leaving the nest for periods of about 30 minutes to hunt.