Dusky Woodswallow
Encyclopedia
The Dusky Woodswallow is a bird
species of forest
s and woodland
s in tropical
and subtropical regions, in eastern and southern Australia
.
The global population
of the species has as yet not been formally confirmed, but it has been officially rated in the range of 'Least Concern', according to the BirdLife International
in 2004. As such, the bird could be described as common in its local habitat
.
The name "woodswallow
" is a misnomer as they are not closely related to true swallow
s. Instead, they belong to the family Artamidae
, which also includes butcherbird
s, currawong
s and the Australian Magpie
.
in 1802; its specific epithet is derived from the Ancient Greek
words cyanos 'blue' and pteron 'wing'.
-like, with a dark brown
hue
, but there have been instances where the bird has appeared grey
. They have a black
patch in front of the eye
s, and grey (sometimes also black) wings with white
streaks on them. The Dusky Woodswallow has a black, white-tipped tail with a silver underwing. The birds have a blue-grey bill capped with black.
Dusky Woodswallows are known to spontaneously 'wag' or swivel their tales fervently, a trait which is common among many other species of woodswallow
.
The Little Woodswallow
, a smaller, darker woodswallow, too, is slightly more smoky brown that other Woodswallows, but that is the only similarity that the latter has with the Dusky Woodswallow; the Little Woodswallow does not share a white patch on the outer wing.
forests and woodland
s. They range mostly from Atherton Tableland
, Queensland
, down to Tasmania
and west to Eyre Peninsula
, in South Australia
. They roost communally, usually nocturnally. During the breeding season, they nest in large flocks to make sure to keep predators away from young. These flocks can be 20-30 Dusky Woodswallows in size.
Dusky Woodswallows adhere to seasonal migration and movements. The birds are a nomad
ic species, and tend to move quite spontaneously. However, one certain change of habitat occurs for the south-eastern birds, who migrate
northward for Autumn.
Communally roosting birds, the Dusky Woodswallow has a variety of chattering calls which are used in certain situations. The most distinctive of these calls is perhaps the one which is used when a predator or intruder approaches, which consists of a harsh mobbing call to warn others.
s, butterflies
and other insect
s. They also eat nectar from flowers. One notable aspect of their feeding habits is the way they hunt flying insects, which is done by picking them up on their wing. They do, however, also eat their prey from the ground, and they often find inconspicuous places to perch while waiting for prey, such as utility lines and the like. They have also been observed engaging in kleptoparasitism
, working as a group to rob a Restless Flycatcher
of its prey. Kleptoparasitism is extremely unusual in passerine
birds, as is cooperative kleptoparasitsim in general.
s and other similar foliage matted together to form a bowl shape, which is lined with grass
. It is positioned safely, behind bark
, and/or high in a tree
branch
, and sometimes in a hollowed out tree stump. The nest
is made during the period from August to January, and with the help of several birds. The mated pair will then guard the nest, while others will help them take care of the babies. The female
lays white eggs, of which there are usually no more than three or four. While the incubation
period lasts for sixteen days, the amount of time taken for fledgling can be this long to around twenty days.
The typical clutch is three to four in size, but this may vary.
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...
species of forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s and woodland
Woodland
Ecologically, a woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of...
s in tropical
Tropics
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately N and the Tropic of Capricorn in the southern hemisphere at S; these latitudes correspond to the axial tilt of the Earth...
and subtropical regions, in eastern and southern 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...
.
The global population
Population
A population is all the organisms that both belong to the same group or species and live in the same geographical area. The area that is used to define a sexual population is such that inter-breeding is possible between any pair within the area and more probable than cross-breeding with individuals...
of the species has as yet not been formally confirmed, but it has been officially rated in the range of 'Least Concern', according to the BirdLife International
BirdLife International
BirdLife International is a global Partnership of conservation organisations that strives to conserve birds, their habitats and global biodiversity, working with people towards sustainability in the use of natural resources...
in 2004. As such, the bird could be described as common in its local habitat
Habitat (ecology)
A habitat is an ecological or environmental area that is inhabited by a particular species of animal, plant or other type of organism...
.
The name "woodswallow
Woodswallow
Woodswallows are soft-plumaged, somber-coloured passerine birds. There is a single genus, Artamus, The woodswallows are either treated as a subfamily, Artaminae in an expanded family Artamidae, which includes the butcherbirds and Australian Magpie, or as the only genus in that family...
" is a misnomer as they are not closely related to true swallow
Swallow
The swallows and martins are a group of passerine birds in the family Hirundinidae which are characterised by their adaptation to aerial feeding...
s. Instead, they belong to the family Artamidae
Artamidae
The family Artamidae gathers together 20 species of mostly crow-like birds native to Australasia and nearby areas.There are two subfamilies: Artaminae, the woodswallows, are sombre-coloured, soft-plumaged birds that have a brush-tipped tongue but seldom use it for gathering nectar. Instead, they...
, which also includes butcherbird
Butcherbird
Butcherbirds are magpie-like birds in the genus Cracticus. They are native to Australasia. Their closest relatives are the three species of currawong...
s, currawong
Currawong
Currawongs are three species of medium-sized passerine birds belonging to the genus Strepera in the family Artamidae native to Australasia. These are the Grey Currawong , Pied Currawong , and Black Currawong . The common name comes from the call of the familiar Pied Currawong of eastern Australia...
s and the Australian Magpie
Australian Magpie
The Australian Magpie is a medium-sized black and white passerine bird native to Australia and southern New Guinea. A member of the Artamidae, it is closely related to the butcherbirds...
.
Taxonomy
The Dusky Woodswallow was first described by the English ornithologist John LathamJohn Latham (ornithologist)
John Latham was an English physician, naturalist and author. He was born at Eltham in Kent, and was the eldest son of John Latham, a surgeon there, and his mother was a descendant of the Sothebys, in Yorkshire....
in 1802; its specific epithet is derived from the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
words cyanos 'blue' and pteron 'wing'.
Description
The Dusky Woodswallow is medium sized and swallowSwallow
The swallows and martins are a group of passerine birds in the family Hirundinidae which are characterised by their adaptation to aerial feeding...
-like, with a dark brown
Brown
Brown is a color term, denoting a range of composite colors produced by a mixture of orange, red, rose, or yellow with black or gray. The term is from Old English brún, in origin for any dusky or dark shade of color....
hue
Hue
Hue is one of the main properties of a color, defined technically , as "the degree to which a stimulus can be describedas similar to or different from stimuli that are described as red, green, blue, and yellow,"...
, but there have been instances where the bird has appeared grey
Grey
Grey or gray is an achromatic or neutral color.Complementary colors are defined to mix to grey, either additively or subtractively, and many color models place complements opposite each other in a color wheel. To produce grey in RGB displays, the R, G, and B primary light sources are combined in...
. They have a black
Black
Black is the color of objects that do not emit or reflect light in any part of the visible spectrum; they absorb all such frequencies of light...
patch in front of the eye
Eye
Eyes are organs that detect light and convert it into electro-chemical impulses in neurons. The simplest photoreceptors in conscious vision connect light to movement...
s, and grey (sometimes also black) wings with white
White
White is a color, the perception of which is evoked by light that stimulates all three types of color sensitive cone cells in the human eye in nearly equal amounts and with high brightness compared to the surroundings. A white visual stimulation will be void of hue and grayness.White light can be...
streaks on them. The Dusky Woodswallow has a black, white-tipped tail with a silver underwing. The birds have a blue-grey bill capped with black.
Dusky Woodswallows are known to spontaneously 'wag' or swivel their tales fervently, a trait which is common among many other species of woodswallow
Woodswallow
Woodswallows are soft-plumaged, somber-coloured passerine birds. There is a single genus, Artamus, The woodswallows are either treated as a subfamily, Artaminae in an expanded family Artamidae, which includes the butcherbirds and Australian Magpie, or as the only genus in that family...
.
Relations to other Woodswallows
A significant difference from other woodswallows that Dusky Woodswallows share is a distinctive white coloured patch on the bird's outer wing. Dusky Woodswallows also seem to typically be more smoky brown than other species of woodswallow.The Little Woodswallow
Little Woodswallow
The Little Woodswallow , is a bird patchily distributed over much of mainland Australia, avoiding only the driest deserts and the area within about 300 kilometres of the southern coastline, and showing a preference for rugged terrain around inland ranges.As its name suggests, at 12 to 14 cm in...
, a smaller, darker woodswallow, too, is slightly more smoky brown that other Woodswallows, but that is the only similarity that the latter has with the Dusky Woodswallow; the Little Woodswallow does not share a white patch on the outer wing.
Distribution and habitat
The birds live primarily in open eucalyptusEucalyptus
Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...
forests and woodland
Woodland
Ecologically, a woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of...
s. They range mostly from Atherton Tableland
Atherton Tableland
The Atherton Tableland is a fertile plateau which is part of the Great Dividing Range in Queensland, Australia. It is located west to south-south-west inland from Cairns, well into the tropics, but its elevated position provides a climate suitable for dairy farming. It has an area of around...
, 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...
, down to Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
and west to Eyre Peninsula
Eyre Peninsula
Eyre Peninsula is a triangular peninsula in South Australia. It is bounded on the east by Spencer Gulf, the west by the Great Australian Bight, and the north by the Gawler Ranges. It is named after explorer Edward John Eyre who explored some of it in 1839-1841. The coastline was first explored by...
, in South Australia
South Australia
South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...
. They roost communally, usually nocturnally. During the breeding season, they nest in large flocks to make sure to keep predators away from young. These flocks can be 20-30 Dusky Woodswallows in size.
Dusky Woodswallows adhere to seasonal migration and movements. The birds are a nomad
Nomad
Nomadic people , commonly known as itinerants in modern-day contexts, are communities of people who move from one place to another, rather than settling permanently in one location. There are an estimated 30-40 million nomads in the world. Many cultures have traditionally been nomadic, but...
ic species, and tend to move quite spontaneously. However, one certain change of habitat occurs for the south-eastern birds, who migrate
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...
northward for Autumn.
Communally roosting birds, the Dusky Woodswallow has a variety of chattering calls which are used in certain situations. The most distinctive of these calls is perhaps the one which is used when a predator or intruder approaches, which consists of a harsh mobbing call to warn others.
Feeding and diet
The diet of the bird can be varied. They eat various forms of foliage and other grassy material that they find on the ground on in trees and shrubs. Dusky Woodswallows have been seen eating termiteTermite
Termites are a group of eusocial insects that, until recently, were classified at the taxonomic rank of order Isoptera , but are now accepted as the epifamily Termitoidae, of the cockroach order Blattodea...
s, butterflies
Butterfly
A butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...
and other 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. They also eat nectar from flowers. One notable aspect of their feeding habits is the way they hunt flying insects, which is done by picking them up on their wing. They do, however, also eat their prey from the ground, and they often find inconspicuous places to perch while waiting for prey, such as utility lines and the like. They have also been observed engaging in kleptoparasitism
Kleptoparasitism
Kleptoparasitism or cleptoparasitism is a form of feeding in which one animal takes prey or other food from another that has caught, collected, or otherwise prepared the food, including stored food...
, working as a group to rob a Restless Flycatcher
Restless Flycatcher
The Restless Flycatcher, Myiagra inquieta, is a passerine bird in the family Monarchidae.Also known colloquially as Scissors Grinder or Dishwasher on account of its unusual call, the Restless Flycatcher was first described by ornithologist John Latham in 1802. Its specific epithet is derived from...
of its prey. Kleptoparasitism is extremely unusual in 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...
birds, as is cooperative kleptoparasitsim in general.
Breeding
The nest of the Dusky Woodswallow consists of twigs, rootRoot
In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
s and other similar foliage matted together to form a bowl shape, which is lined 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 ...
. It is positioned safely, behind bark
Bark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
, and/or high in a tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
branch
Branch
A branch or tree branch is a woody structural member connected to but not part of the central trunk of a tree...
, and sometimes in a hollowed out tree stump. 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 made during the period from August to January, and with the help of several birds. The mated pair will then guard the nest, while others will help them take care of the babies. The female
Female
Female is the sex of an organism, or a part of an organism, which produces non-mobile ova .- Defining characteristics :The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon, is produced by the male...
lays white eggs, of which there are usually no more than three or four. While the incubation
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...
period lasts for sixteen days, the amount of time taken for fledgling can be this long to around twenty days.
The typical clutch is three to four in size, but this may vary.