Red-backed Fairy-wren

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Red-backed Fairy-wren
male (ssp. melanocephalus) in breeding plumage carrying red petal, Noosa
Conservation status
Least Concern[1]
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Aves Order: Passeriformes Family: Maluridae Genus: Malurus Species: M. melanocephalus
Binomial name
Malurus melanocephalus (Latham, 1801)

The Red-backed Fairy-wren (Malurus melanocephalus) is a species of passerine bird in the fairy-wren family Maluridae. It is endemic to Australia and can be located along rivers and coastal areas along the northern and eastern coastlines of Australia from the Kimberleys in the northwest to the Hunter River region in New South Wales, preferring moist grassy areas. Two subspecies are recognised, the nominate form melanocephalus native to eastern Australia and the short-tailed form cruentatus from northern Australia.

The Red-backed Fairy-wren mainly eats insects, and supplements its diet with seed and small fruit. It is found in heathland and savannah, where low shrubs and particularly tall grasses provide cover. Like other fairy-wrens, it is a cooperative breeding species, with small groups of birds maintaining and defending territories year-round. Groups consist of a socially monogamous pair with several helper birds who assist in raising the young. These helpers are progeny that have attained sexual maturity yet remain with the family group for one or more years after fledging. Although not yet confirmed genetically, the Red-backed Fairy-wren may be sexually promiscuous, meaning that although they form pairs between one male and one female, each partner will mate with other individuals and even assist in raising the young from such pairings. As part of a courtship display, the male wren plucks red petals from flowers and displays them to females.

Contents 1 Taxonomy 1.1 Subspecies 1.2 Evolutionary history 2 Description 2.1 Vocalizations 3 Distribution and habitat 4 Behaviour 4.1 Feeding 4.2 Courtship and breeding 5 Footnotes 5.1 Cited texts 6 External links

[edit] Taxonomy

The Red-backed Fairy-wren was first collected from the vicinity of Port Stephens in New South Wales and described by ornithologist John Latham in 1801 as the Black-headed Flycatcher (Muscicapa melanocephala); its specific epithet derived from the Ancient Greek melano- 'black' and kephalos 'head'.^[2] However, the specimen used by Latham was a male in partial moult, with mixed black and brown plmage and orange back, and he named it for its black head. A male in full adult plumage was described as Sylvia dorsalis, while the explorers Nicholas Aylward Vigors and Thomas Horsfield gave another specimen from central Queensland the name Malurus brownii, honouring botanist Robert Brown. John Gould described Malurus cruentatus in 1840 from a short-tailed scarlet backed specimen collected in Northwestern Australia by Benjamin Bynoe aboard the HMS Beagle on its third voyage. The first three names were synonymised into Malurus melanocephalus by Gould who continued to recognise his form as a separate species. An intermediate form from north Queensland was described as pyrrhonotus. Ornithologist Tom Iredale proposed the common name Elfin-wren in 1939, however this was not taken up.^[3]

Like other fairy-wrens, the Red-backed Fairy-wren is unrelated to the true wren (family Troglodytidae). It was previously classified as a member of the old world flycatcher family Muscicapidae^[4][5] and later as a member of the warbler family Sylviidae^[6] before being placed in the newly recognised fairy-wren family Maluridae in 1975.^[7] More recently, DNA analysis has shown the Maluridae family to be related to the Meliphagidae (honeyeaters), the Pardalotidae (pardalotes, scrubwrens, thornbills, gerygones and allies), and the Petroicidae (Australian robins) in the large superfamily Meliphagoidea.^[8][9]

Within the Maluridae, it is one of 12 species in its genus, Malurus. It is most closely related to the Australian White-winged Fairy-wren, with which it makes up a phylogenetic clade, with the White-shouldered Fairy-wren of New Guinea as the next closest relative.^[10] Termed the bicoloured wrens by ornithologist Richard Schodde, these three species are notable for their lack of head patterns and ear tufts, and one-coloured black or blue plumage with contrasting shoulder or wing colour; they replace each other geographically across northern Australia and New Guinea.^[11]

[edit] Subspecies

George Mack, ornithologist of the National Museum of Victoria, was the first to classify the three forms melanocephalus, cruentatus and pyrrhonotus as one species,^[12] although Richard Schodde reclassified pyrrhonotus as a hybrid from a broad hybrid zone in North Queensland. Here, in an area bounded by the Burdekin, Endeavour and Norman Rivers, breeding males of intermediate plumage, larger and scarlet-backed, or smaller and orange-backed are encountered, as well as forms resembling one of the two parent subspecies.

Two subspecies are recognised:

• M. m. melanocephalus, the nominate subspecies, has an orange back and longer tail and is found from northern coastal New South Wales through to North Queensland. This form has been previously called the Orange-backed Fairy-wren.

• M. m. cruentatus occurs across Northern Australia from the Kimberleys to northern Queensland. It is smaller than the nominate species, with males averaging 7.1 g (0.25 oz) and females 6.6 g (0.23 oz) in weight.^[13] Males in breeding plumage on Melville Island have a deeper crimson colour to their back.^[14] Cruentatus 'bloodstained' is derived from the Latin verb cruentare 'to stain with blood'.^[15]

[edit] Evolutionary history

Ornithologist Richard Schodde has proposed the ancestors of the two subspecies were separated during the last glacial period in the Pleistocene around 12000 years ago. Aridity had pushed the grasslands preferred by the wren to the north, and with subsequent wetter warmer conditions it once again spread southwards and met the eastern form in northern Queensland and intermediate forms arose.^[14]

[edit] Description

The smallest member of the genus Malurus, the Red-backed Fairy-wren measures 11.5 cm (4½ in) and weighs between 5–10 g (0.18–0.35 oz), averaging around 8 g (0.21 oz). The 6 cm (2½ in) long tail is black in the breeding male, and brown in eclipse males, females and juvenile birds.^[13] Averaging 8.6 mm (0.3 in), the bill is relatively long, narrow and pointed and wider at the base.^[16] Wider than it is deep, the bill is similar in shape to those of other birds that feed by probing for or picking insects off their environs.^[17]

Like other fairy-wrens, the Red-backed Fairy-wren is notable for its marked sexual dimorphism; the male adopts full breeding plumage by the fourth year, later than all other fairy-wrens apart from its relative the White-winged Fairy-wren.^[18] The male in breeding plumage has a black head and body with striking red back and brown wings. At other times it has a brown upper body and white underparts. The females look remarkably similar with buff brown bodies and a yellowish spot under the eye. ^[19] The females of this species differ from females of other fairy wren species in that they lack blue tint in the tail.^[20] Geographically, they follow Gloger's rule, with whiter bellies and paler brown upperparts inland in sunnier climates.^[14] Juveniles of both sexes look very similar to females.^[21]

[edit] Vocalizations

Their typical song for advertising their territory is similar to that of other fairy wrens, a reel made up an introductory note followed by repeated short segments of song, starting weak and soft and ending high and shrill with several syllables. The call is mostly made by males during mating season.^[22][23] Birds will communicate with one another while foraging with a soft ssst, barely able to be heard further than 10-15 m (30-50 ft) away. The alarm call is a high-pitched zit.^[13]

[edit] Distribution and habitat

The Red-backed Fairy-wren is endemic to Australia and can be located along rivers and the coast from Cape Keraudren in northern Western Australia through the Kimberleys, Arnhem Land and the Gulf Country and into Cape York, with the Selwyn Range and upper reaches of the Flinders River as a southern limit. It is also found on the nearby offshore islands Groote Eylandt, Sir Edmund Pellew, Fraser, Melville and Bathurst Islands. It then occurs all the way down the east coast east of the Great Dividing Range to the Hunter River in New South Wales,^[24] preferring moist grassy areas. It prefers wet, grassy tropical or sub-tropical areas, with tall grasses such as bladygrass (Imperata cylindrica), species of Sorghum, and Eulalia. Birds will retreat to fire-resistant cover at times of fire.^[25] Research has shown that they do not fare well in arid places or areas prone to fire, which explains their preference for coastal Australia. In the damp areas they prefer, the wrens feed primarily on insects. They leave their territories after breeding season and travel locally. They do not migrate very far, however. While home, they can be found hunting for insects in leaf litter, shrubbery and on the edges of bodies of water, mostly in the morning and late afternoon. Adults of both sexes as well as helper birds feed the young. The biggest threat the species faces is the feral cat (Felis catus), followed by rodents raiding nests for eggs or hatchlings. ^[26]

[edit] Behaviour

The Red-backed Fairy-wren is diurnal, becoming active at dawn and then in bursts through the day. Between foraging, a troop often shelters together. Birds roost side-by-side in dense cover as well and engage in mutual preening.^[27] The usual form of locomotion is hopping, with both feet leaving the ground and landing simultaneously. However, birds may run when performing the rodent-run display.^[28] Its balance is assisted by a proportionally large tail, which is usually held upright and rarely still. The short, rounded wings provide good initial lift and are useful for short flights, though not for extended jaunts.^[29] Birds generally fly in a series of undulations for a maximum of 20 or 30 m (60-100 ft)^[25]

In dry tall grasslands in monsoonal areas, the change in vegetation may be so great due to either fires or wet season growth that birds may be more nomadic and change territories more than other fairy-wrens.^[25] They form more stable territories elsewhere, such as in coastal areas.^[25]

Both the male and female adult Red-backed Fairy-wren may utilise the rodent-run display to distract predators from nests with young birds. The head, neck and tail are lowered, the wings are held out and the feathers are fluffed as the bird runs rapidly and voices a continuous alarm call.^[30]

[edit] Feeding

Like other fairy-wrens, the Red-backed Fairy-wren is predominantly insectivorous; it consumes a wide variety of insects, including beetles such as weevils, leaf-, jewel-, flea- and ground-beetles, bugs, grasshoppers, moths, wasps and cicadas. Insect larvae and eggs are eaten as well as spiders. Seeds and other plant material make up only a very small proportion of their diet.^[31]

[edit] Courtship and breeding

During the mating season, the male molts its brown feathers and displays a fiery red plumage. It may fluff its red back and shoulder feathers out so they cover part of the wings in a puffball-display. Here it will fly about and confront another male to repel it, or to assert dominance over a female.^[32][33] It also picks red petals off flowers and sometimes red seeds up and presents them to other birds. 90% of the time, the males present to females in what appears to be a courtship ritual. The other 10% of the time, they present to other males in an act of apparent aggression.^[34]

The fairy wren used to be known as the "Mormon Wren" as it had apparently had only one mate per season. Over half the Red-backed Fairy-wrens in an area can be found in pairs during the mating season. This is apparently a defense against the resource-limited nature of the environment. It is more difficult to maintain larger interdependent populaces during dry spells, so the birds try to stay in pairs or smaller groupings, which include adults that help parents look after young. ^[35] However, paternity tests have shown that older males with bright plumage have much more success in the mating season and can mate with more than one female. Accordingly, they have higher sperm storages and make more mating overtures towards females. Males with browner and less bright plumage and also younger males with bright plumage have much lower success rates than bright, older males for mating.^[36] Further, unpaired males serve as helpers to mated pairs in terms of feeding and care of young. To denote the status of being paired or unpaired, the males experience a bill darkening. The bill will darken within three weeks of being paired. This is much easier to control than plumage, as molting takes time and is controlled by seasonality. The bill is vascular and much easier to change in response to the pairings. ^[37]

The mating season lasts from August to February. The nest is located on top of grass tussocks and is spherical. it is constructed of dried grasses and are usually lined with smaller, finer grasses.^[38] The eggs produced are white with reddy-brown spots in clutches of three to four.^[39] The eggs are incubated for two weeks by the female alone. The nestlings are hidden under cover for one week after hatching. The juveniles depend on parents and helpers for approximately one month. They learn to fly between 11–12 days after hatching. Broods hatched earlier in the season will help to raise the broods hatched later on. They will stay as a clutch group for the season after hatching. ^[40]

[edit] Footnotes

[edit] Cited texts

• Rowley, Ian; Russell, Eleanor (1997). Bird Families of the World: Fairy-wrens and Grasswrens. Oxford: Oxford University Press. ISBN 0-19-854690-4. 
• Schodde, Richard (1982). The fairy-wrens: a monograph of the Maluridae.. Melbourne: Lansdowne Editions. ISBN 0-7018-1051-3. 

[edit] External links

• IUCN Red List
• Red-backed Fairy-wren videos on the Internet Bird Collection