The common blackbird ( Turdus merula) is a species of true thrush. It is also called the Eurasian blackbird (especially in North America, to distinguish it from the unrelated New World blackbirds),
The adult male of the common blackbird ( Turdus merula merula, the nominate subspecies), which is found throughout most of Europe, is all black except for a yellow eye-ring and Beak and has a rich, melodious song; the adult female and juvenile have mainly dark brown plumage. This species breeds in woods and gardens, building a neat, cup-shaped nest, bound together with mud. It is omnivorous, eating a wide range of insects, , Berry, and fruits.
Both sexes are territorial on the breeding grounds, with distinctive threat displays, but are more gregarious during migration and in wintering areas. Pairs stay in their territory throughout the year where the climate is sufficiently temperate. This common and conspicuous species has given rise to a number of literary and cultural references, frequently related to its song.
About 65 species of medium to large thrushes are in the genus Turdus, characterised by rounded heads, longish, pointed wings, and usually melodious songs. Although two European thrushes, the song thrush and mistle thrush, are early offshoots from the Eurasian lineage of Turdus thrushes after they spread north from Africa, the blackbird is descended from ancestors that had colonised the Canary Islands from Africa and subsequently reached Europe from there.
It may not immediately be clear why the name "blackbird", first recorded in 1486, was applied to this species, but not to one of the various other common black English birds, such as the carrion crow, common raven, rook, or jackdaw. However, in Old English, and in modern English up to about the 18th century, "bird" was used only for smaller or young birds, and larger ones such as crows were called "fowl". At that time, the blackbird was therefore the only widespread and conspicuous "black bird" in the British Isles. Oxford English Dictionary, Oxford University Press, 1933: Bird (sense 2), Blackbird Until about the 17th century, another name for the species was ouzel, ousel or wosel (from Old English osle, cf. German Amsel). Another variant occurs in Act 3 of William Shakespeare's A Midsummer Night's Dream, where Nick Bottom refers to "The Woosell cocke, so blacke of hew, With Orenge-tawny bill". The ouzel usage survived later in poetry, and still occurs as the name of the closely related ring ouzel ( Turdus torquatus), and in water ouzel, an alternative name for the unrelated but superficially similar white-throated dipper ( Cinclus cinclus).
Five related Asian Turdus thrushes—the white-collared blackbird ( T. albocinctus), the grey-winged blackbird ( T. boulboul), the Indian blackbird ( T. simillimus), the Tibetan blackbird ( T. maximus), and the Chinese blackbird ( T. mandarinus)—are also named blackbirds; the latter three species were formerly treated as conspecific with the common blackbird. In addition, the Somali thrush ( T. (olivaceus) ludoviciae) is alternatively known as the Somali blackbird.Sinclair, I., & P. Ryan (2003). Birds of Africa south of the Sahara. Struik Publishers, Cape Town.
The icterid family of the New World is sometimes called the blackbird family because of some species' superficial resemblance to the common blackbird and other Old World thrushes, but they are not evolutionarily close, being related to the New World warblers and . The term is often limited to smaller species with mostly or entirely black plumage, at least in the breeding male, notably the , the Quiscalus, and for around 20 species with "blackbird" in the name, such as the red-winged blackbird and the melodious blackbird.
The Central Asian subspecies, the relatively large intermedius, also differs in structure and voice, and may represent a distinct species.Collar, N. J. (2005). Common Blackbird ( Turdus merula). p. 645 in: del Hoyo, J., Elliott, A., & Christie, D. A. eds. (2005) Handbook of the Birds of the World. Vol. 10. Cuckoo-shrikes to Thrushes. Lynx Edicions, Barcelona. Alternatively, it has been suggested that it should be considered a subspecies of T. maximus, but it differs in structure, voice and the appearance of the eye-ring.Collar, N. J. (2005). Tibetan Blackbird ( Turdus maximus). p. 646 in: del Hoyo, J., Elliott, A., & Christie, D. A., eds. (2005). Handbook of the Birds of the World. Vol. 10: Cuckoo-shrikes to Thrushes. Lynx Edicions, Barcelona.
Common over most of its range in woodland, the common blackbird has a preference for deciduous trees with dense undergrowth. However, gardens provide the best breeding habitat with up to 7.3 pairs per hectare (nearly three pairs per acre), with woodland typically holding about a tenth of that density, and open and very built-up habitats even less. They are often replaced by the related ring ouzel in areas of higher altitude. The common blackbird also lives in parks, gardens and hedgerows.
The common blackbird occurs at elevations of up to in Europe, in North Africa, and at in peninsular India and Sri Lanka, but the large Himalayan subspecies range much higher, with T. m. maximus breeding at and remaining above even in winter.
This widespread species has occurred as a vagrant in many locations in Eurasia outside its normal range, but records from North America are normally considered to involve escapees, including, for example, the 1971 bird in Quebec. However, a 1994 record from Bonavista, Newfoundland, has been accepted as a genuine wild bird, and the species is therefore on the North American list.
The beak's appearance is important in the interactions of the common blackbird. The territory-holding male responds more aggressively towards models with orange bills than to those with yellow bills, and reacts least to the brown bill colour typical of the first-year male. The female is, however, relatively indifferent to bill colour, but responds instead to shinier bills.
As long as winter food is available, both the male and female will remain in the territory throughout the year, although occupying different areas. Migrants are more gregarious, travelling in small flocks and feeding in loose groups in the wintering grounds. The flight of migrating birds comprises bursts of rapid wing beats interspersed with level or diving movement, and differs from both the normal fast agile flight of this species and the more dipping action of larger thrushes.
The nominate T. merula may commence breeding in March, but eastern and Indian races are a month or more later, and the introduced New Zealand birds start nesting in August (late winter). The breeding pair prospect for a suitable nest site in a creeper or bush, favouring evergreen or thorny species such as ivy, holly, crataegus, honeysuckle or pyracantha. Sometimes the birds will nest in sheds or outbuildings where a ledge or cavity is used. The cup-shaped bird nest is made with grasses, leaves and other vegetation, bound together with mud. It is built by the female alone. She lays three to five (usually four) bluish-green Bird egg marked with reddish-brown blotches, heaviest at the larger end; the eggs of nominate T. merula are in size and weigh , of which 6% is shell. Eggs of birds of the southern Indian races are paler than those from the northern subcontinent and Europe.
The female incubates for 12–14 days before the altricial chicks are hatched naked and blind. Fledging takes another 10–19 (average 13.6) days, with both parents feeding the young and removing faecal sacs. The nest is often ill-concealed compared with those of other species, and many breeding attempts fail due to predation. The young are fed by the parents for up to three weeks after leaving the nest, and will follow the adults begging for food. If the female starts another nest, the male alone will feed the fledged young. Second broods are common, with the female reusing the same nest if the brood was successful, and three broods may be raised in the south of the common blackbird's range.
A common blackbird has an average life expectancy of 2.4 years, and, based on data from bird ringing, the oldest recorded age is 21 years and 10 months.
In its native Northern Hemisphere range, the first-year male common blackbird of the nominate race may start singing as early as late January in fine weather in order to establish a territory, followed in late March by the adult male. The male's song is a varied and melodious low-pitched fluted warble, given from trees, rooftops or other elevated perches mainly in the period from March to June, sometimes into the beginning of July. It has a number of other calls, including an aggressive seee, a pook-pook-pook alarm for terrestrial predators like cats, and various chink and chook, chook vocalisations. The territorial male invariably gives chink-chink calls in the evening in an attempt (usually unsuccessful) to deter other blackbirds from roosting in its territory overnight. During the northern winter, blackbirds can be heard quietly singing to themselves, so much so that September and October are the only months in which the song cannot be heard. Like other passerine birds, it has a thin high seee alarm call for threats from birds of prey since the sound is rapidly attenuated in vegetation, making the source difficult to locate.
The nominate subspecies T. m. merula is known to mimic sounds in the local environment, including the songs of other birds, as well as human sounds and technology such as whistling and car alarms.
This species is occasionally a host of brood parasite , such as the common cuckoo ( Cuculus canorus), but this is minimal because the common blackbird recognizes the adult of the parasitic species and its mimicry eggs. In the UK, only three nests of 59,770 examined (0.005%) contained cuckoo eggs. The introduced merula blackbird in New Zealand, where the cuckoo does not occur, has, over the past 130 years, lost the ability to recognize the adult common cuckoo but still rejects non-mimetic eggs.
As with other passerine birds, parasites are common. Intestinal parasites were found in 88% of common blackbirds, most frequently Isospora and Capillaria species. and more than 80% had haematozoan parasites ( Leucocytozoon, Plasmodium, Haemoproteus and Trypanosoma species).
Common blackbirds spend much of their time looking for food on the ground where they can become infested with ticks, which are external parasites that most commonly attach to the head of a blackbird. In France, 74% of rural blackbirds were found to be infested with Ixodes ticks, whereas, only 2% of blackbirds living in urban habitats were infested. This is partly because it is more difficult for ticks to find another host on lawns and gardens in urban areas than in uncultivated rural areas, and partly because ticks are likely to be commoner in rural areas, where a variety of tick hosts, such as foxes, deer and boar, are more numerous. Although ixodid ticks can transmit viruses and bacteria, and are known to transmit Borrelia bacteria to birds, there is no evidence that this affects the fitness of blackbirds except when they are exhausted and run down after migration.
The common blackbird is one of a number of species which has unihemispheric slow-wave sleep. One hemisphere of the brain is effectively asleep, while a low-voltage EEG, characteristic of wakefulness, is present in the other. The benefit of this is that the bird can rest in areas of high predation or during long migratory flights, but still retain a degree of alertness.
The common blackbird was introduced to Australia by a bird dealer visiting Melbourne in early 1857, and its range has expanded from its initial foothold in Melbourne and Adelaide to include all of southeastern Australia, including Tasmania and the Bass Strait islands. The introduced population in Australia is considered a pest because it damages a variety of soft fruits in orchards, parks and gardens, including berries, cherries, stone fruit and grapes.Clarke, G. M.; Gross, S., Matthews, M.; Catling, P. C.; Baker, B.; Hewitt, C. L.; Crowther, D.; Saddler, S. R. (2000), Environmental Pest Species in Australia, Australia: State of the Environment, Second Technical Paper Series (Biodiversity), Department of the Environment and Heritage, Canberra. It is thought to spread weeds, such as blackberry, and may compete with native birds for food and nesting sites.
The introduced common blackbird is, together with the native silvereye ( Zosterops lateralis), the most widely distributed avian seed disperser in New Zealand. Introduced there along with the song thrush ( Turdus philomelos) in 1862, it has spread throughout the country up to an elevation of , as well as outlying islands such as the Campbell and Kermadec Islands.Falla, R. A., R. B. Sibson, and E. G. Turbott (1979). The new guide to the birds of New Zealand and outlying islands. Collins, Auckland. It eats a wide range of native and exotic fruit, and makes a major contribution to the development of communities of naturalised woody weeds. These communities provide fruit more suited to non-endemic native birds and naturalised birds than to Endemism birds.
The numbers of blackbirds in Europe have been significantly reduced by the Usutu virus which is spread by mosquitoes. This was detected in Italy in 1996 and has since spread to other countries including Germany and the UK.
The common blackbird's melodious, distinctive song is mentioned in the poem Adlestrop by Edward Thomas;
In the English Christmas carol "The Twelve Days of Christmas", the line commonly sung today as "four calling birds" is believed to have originally been written in the 18th century as "four colly birds", an archaism meaning "black as coal" that was a popular English nickname for the common blackbird.
The common blackbird, unlike many black creatures, is not normally seen as a symbol of bad luck, but R. S. Thomas wrote that there is "a suggestion of dark Places about it", and it symbolised resignation in the 17th century tragedy play The Duchess of Malfi; an alternate connotation is vigilance, the bird's clear cry warning of danger.
The common blackbird is the national bird of Sweden, which has a breeding population of 1–2 million pairs, and was featured on a 30 öre Christmas postage stamp in 1970; it has also featured on a number of other stamps issued by European and Asian countries, including a 1966 4d British stamp and a 1998 Irish 30p stamp. This bird—arguably—also gives rise to the Serbian language name for Kosovo (and Metohija), which is the possessive adjectival form of Serbian kos ("blackbird") as in Kosovo Polje ("Blackbird Field").
French composer Olivier Messiaen transcribed the songs of male blackbirds; these melodies have commonly appeared throughout his œuvre. The most notable instance of this is the 1952 chamber miniature Le merle noir, a piece for flute and piano.
A common blackbird can be heard singing on the Beatles song "Blackbird" as a symbol of the civil rights movement.
Subspecies
Similar species
Description
Distribution and habitat
Behaviour and ecology
Breeding
Songs and calls
Song 1 Song 2 Song 3 Song 4 Alarm calls
Feeding
Natural threats
Status and conservation
In popular culture
Sing a song of sixpence,
A pocket full of rye;
Four and twenty blackbirds baked in a pie!
When the pie was opened the birds began to sing,
Oh, wasn't that a dainty dish to set before the king?And for that minute a blackbird sang
Close by, and round him, mistier,
Farther and farther, all the birds
Of Oxfordshire and Gloucestershire.
Footnotes
Further reading
External links
Species information
Sounds and videos
Images
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