The Eurasian magpie or common magpie (Pica pica) is a resident breeding bird throughout the northern part of the Eurasian continent. It is one of several birds in the crow family (corvids) designated magpies, and belongs to the Holarctic radiation of "monochrome" magpies. In Europe, "magpie" is used by English speakers as a synonym for the Eurasian magpie: the only other magpie in Europe is the Iberian magpie (Cyanopica cooki), which is limited to the Iberian Peninsula. Despite having a shared name and similar colouration, it is not closely related to the Australian Magpie.
The Eurasian magpie is one of the most intelligent birds, and it is believed to be one of the most intelligent of all non-human animals.[2] The expansion of its nidopallium is approximately the same in its relative size as the brain of chimpanzees, gorillas, orangutans and humans.[3] It is the only bird known to pass the mirror test, along with very few other non-avian species.
The Eurasian magpie is almost identical in appearance to the North American black-billed magpie (Pica hudsonia) and at one time the two species were considered to be conspecific.[5][10] In 2000, the American Ornithologists' Union decided to treat the black-billed magpie as a separate species based on studies of the vocalization and behaviour that indicated that the black-billed magpie was closer to the yellow-billed magpie (Pica nuttalli) than to the Eurasian magpie.[11]
The gradual clinal variation over the large geographic range and the intergradation of the different subspecies means that the geographical limits, and acceptance of the various subspecies, vary between authorities. The International Ornithological Congress recognises six subspecies (a seventh, P. p. hemileucoptera, is included in P. p. bactriana):[12]
P. p. fennorum – Lönnberg, 1927: northern Scandinavia and northwest Russia
P. p. pica – (Linnaeus, 1758): British Isles and southern Scandinavia east to Russia, south to Mediterranean, including most islands
P. p. melanotos – A.E. Brehm, 1857: Iberian Peninsula
P. p. bactriana – Bonaparte, 1850: Siberia east to Lake Baikal, south to Caucasus, Iraq, Iran, Central Asia and Pakistan
P. p. leucoptera – Gould, 1862: southeast Russia and northeast China
P. mauritanica – Malherbe, 1845: North Africa (Morocco, northern Algeria and Tunisia) (now considered a separate species, the Maghreb magpie)[13]
P. asirensis – Bates, 1936: southwest Saudi Arabia (now considered a separate species, the Asir magpie)[14]
P. serica – Gould, 1845: east and south China, Taiwan, north Myanmar, north Laos and north Vietnam (now considered a separate species, the Oriental magpie)
P. bottanensis – Delessert, 1840: west central China (now considered a separate species, the black-rumped magpie)
A study using both mitochondrial and nuclear DNA found that magpies in eastern and northeastern China are genetically very similar to each other, but differ from those in northwestern China and Spain.[15]
Etymology
Magpies were originally known as simply "pies". This is hypothesized to derive from a Proto-Indo-European root*(s)peyk- meaning "pointed", in reference to the beak or perhaps the tail (cf. woodpecker). The prefix "mag" dates from the 16th century and comes from the short form of the given name Margaret, which was once used to mean women in general (as Joe or Jack is used for men today); the pie's call was considered to sound like the idle chattering of a woman, and so it came to be called the "Mag pie".[16] "Pie" as a term for the bird dates to the 13th century, and the word "pied", first recorded in 1552, became applied to other birds that resembled the magpie in having black-and-white plumage.[17]
Description
The adult male of the nominate subspecies, P.p.pica, is 44–46cm (17–18in) in length, of which more than half is the tail. The wingspan is 52–62cm (20–24in).[18] The head, neck and breast are glossy black with a metallic green and violet sheen; the belly and scapulars (shoulder feathers) are pure white; the wings are black glossed with green or purple, and the primaries have white inner webs, conspicuous when the wing is open. The graduated tail is black, glossed with green and reddish purple. The legs and bill are black; the iris is dark brown.[19] The plumage of the sexes is similar but females are slightly smaller. The tail feathers of both sexes are quite long, about 12–28cm long. Males of the nominate subspecies weigh 210–272g (7.4–9.6oz) while females weigh 182–214g (6.4–7.5oz). The young resemble the adults, but are at first without much of the gloss on the sooty plumage. The young have the malar region pink, and somewhat clear eyes. The tail is much shorter than the adults.[18]
The subspecies differ in their size, the amount of white on their plumage and the colour of the gloss on their black feathers. The Asian subspecies P. p. bactriana has more extensive white on the primaries and a prominent white rump.[19]
Adults undergo an annual complete moult after breeding. Moult begins in June or July and ends in September or October. The primary flight feathers are replaced over a period of three months. Juvenile birds undergo a partial moult beginning about one month later than the adult birds in which their body feathers are replaced but not those of the wings or the tail.[20]
Eurasian magpies have a well-known call. It is a choking chatter "chac-chac" or a repetitive "chac-chac-chac-chac". The young also emit the previous call, although they also emit an acute call similar to a "Uik Uik", which may resemble the barking of a small dog. Both adults and young can emit a kind of hiss barely noticeable from afar.
Skull of a Eurasian magpie
In flight, showing the numerous brightly coloured sheens on its feathers
A magpie's underside visible as it prepares to land
Distribution and habitat
The range of the magpie extends across temperate Eurasia from Portugal, Spain and Ireland in the west to the Kamchatka Peninsula.[19]
The preferred habit is open countryside with scattered trees and magpies are normally absent from treeless areas and dense forests.[19] They sometimes breed at high densities in suburban settings such as parks and gardens.[21][22] They can often be found close to the centre of cities.[23]
Magpies are normally sedentary and spend winters close to their nesting territories but birds living near the northern limit of their range in Sweden, Finland and Russia can move south in harsh weather.[19]
Behaviour and ecology
P. p. bactriana in LadakhA recently fledged magpie
Some magpies breed after their first year, while others remain in the non-breeding flocks and first breed in their second year.[24] They are monogamous, and the pairs often remain together from one breeding season to the next. They generally occupy the same territory on successive years.[25]
Mating takes place in spring. In the courtship display, males rapidly raise and depress their head feathers, uplift, open and close their tails like fans, and call in soft tones quite distinct from their usual chatter. The loose feathers of the flanks are brought over the primaries, and the shoulder patch is spread so the white is conspicuous, presumably to attract females. Short buoyant flights and chases follow.
Magpies prefer tall trees for their bulky nest, firmly attaching them to a central fork in the upper branches. A framework of the sticks is cemented with earth and clay, and a lining of the same is covered with fine roots. Above is a stout though loosely built dome of prickly branches with a single well-concealed entrance. These huge nests are conspicuous when the leaves fall. Where trees are scarce, though even in well-wooded country, nests are at times built in bushes and hedgerows.
In Europe, clutches are typically laid in April,[26] and usually contain five or six eggs, but clutches with as few as three and as many as ten have been recorded.[27] The eggs are laid in early morning, usually at daily intervals.[28] On average, the eggs of the nominate species measure 32.9mm ×23mm (1.30in ×0.91in) and weigh 9.9g (0.35oz).[28][29] Small for the size of the bird, they are typically pale blue-green, with close specks and spots of olive brown, but show much variation in ground and marking.[30]
The eggs are incubated for 21–22 days by the female, who is fed on the nest by the male.[31] The chicks are altricial, hatching nearly naked with closed eyes. They are brooded by the female for the first 5–10 days and fed by both parents.[32] Initially the parents eat the faecal sacs of the nestlings, but as the chicks grow larger, they defecate on the edge of the nest.[33] The nestlings open their eyes 7 to 8 days after hatching. Their body feathers start to appear after around 8 days and the primary wing feathers after 10 days.[34] For several days before they are ready to leave the nest, the chicks clamber around the nearby branches.[35] They fledge at around 27 days.[34] The parents then continue to feed the chicks for several more weeks. They also protect the chicks from predators, as their ability to fly is poor, making them vulnerable.[34] On average, only 3 or 4 chicks survive to fledge successfully. Some nests are lost to predators, but an important factor causing nestling mortality is starvation. Magpie eggs hatch asynchronously, and if the parents have difficulty finding sufficient food, the last chicks to hatch are unlikely to survive.[36] Only a single brood is reared, unless disaster overtakes the first clutch.[19]
A nest made by Eurasian magpie.
A study conducted near Sheffield in Britain, using birds with coloured rings on their legs, found that only 22% of fledglings survived their first year. For subsequent years, the survival rate for the adult birds was 69%, implying that for those birds that survive the first year, the average total lifespan was 3.7years.[37] The maximum age recorded for a magpie is 21 years and 8 months for a bird from near Coventry in England that was ringed in 1925 and shot in 1947.[38][39]
Feeding
The magpie is omnivorous, eating young birds and eggs, small mammals,[40]insects, scraps and carrion, acorns, grain, and other vegetable substances.
Intelligence
The Eurasian magpie is believed to be not only among the most intelligent of birds, but also among the most intelligent of all animals. Along with the western jackdaw, the Eurasian magpie's nidopallium is approximately the same relative size as those in chimpanzees and humans and significantly larger than the gibbons.[3] Like other corvids, such as ravens and crows, their total brain-to-body mass ratio is equal to most great apes and cetaceans.[41] A 2004 review suggests that the intelligence of the corvid family to which the Eurasian magpie belongs is equivalent to that of the great apes (bonobos, gorillas and orangutans) in terms of social cognition, causal reasoning, flexibility, imagination and prospection.[42]
Magpies have been observed engaging in elaborate social rituals, possibly including the expression of grief.[43]Mirror self-recognition has been demonstrated in European magpies,[44] making them one of only a few species known to possess this capability.[2] The cognitive abilities of the Eurasian magpie are regarded as evidence that intelligence evolved independently in both corvids and primates. This is indicated by tool use, an ability to hide and store food across seasons, episodic memory, and using their own experience to predict the behavior of conspecifics.[2] Another behaviour exhibiting intelligence is cutting their food in correctly sized proportions for the size of their young. In captivity, magpies have been observed counting up to get food,[clarification needed] imitating human voices, and regularly using tools to clean their own cages.[citation needed] In the wild, they organise themselves into gangs and use complex strategies[examples needed] hunting other birds and when confronted by predators.[45]
Status
The Eurasian magpie has an extremely large range. The European population is estimated to be between 7.5 and 19 million breeding pairs. Allowing for the birds breeding in other continents, the total population is estimated to be between 46 and 228 million individuals. The population trend in Europe has been stable since 1980.[46] There is no evidence of any serious overall decline in numbers, so the species is classified by the International Union for Conservation of Nature as being of Least Concern.[1]
In Europe, magpies have been historically demonized by humans, mainly as a result of superstition and myth. The bird has found itself in this situation mainly by association, says Steve Roud: "Large black birds, like crows and ravens, are viewed as evil in British folklore and white birds are viewed as good".[47] In European folklore, the magpie is associated with a number of superstitions[48] surrounding its reputation as an omen of ill fortune. In the 19th century book, A Guide to the Scientific Knowledge of Things Familiar, a proverb concerning magpies is recited: "A single magpie in spring, foul weather will bring". The book further explains that this superstition arises from the habits of pairs of magpies to forage together only when the weather is fine. In Scotland, a magpie near the window of the house is said to foretell death.[49] An English tradition holds that a single magpie be greeted with a salutation in order to ward off the bad luck it may bring. A greeting might be something like "Good morning, Mr Magpie, how are Mrs Magpie and all the other little magpies?",[50] and a 19th century version recorded in Shropshire is to say "Devil, Devil, I defy thee! Magpie, magpie, I go by thee!" and to spit on the ground three times.[51]
In Britain and Ireland, a widespread traditional rhyme, "One for Sorrow", records the myth (it is not clear whether it has been seriously believed) that seeing magpies predicts the future, depending on how many are seen. There are many regional variations on the rhyme, which means that it is impossible to give a definitive version.[49][52]
In Italian, British and French folklore, magpies are believed to have a penchant for picking up shiny items, particularly precious stones or metal objects. Rossini's operaLa gazza ladra and The Adventures of Tintin comic The Castafiore Emerald are based on this theme. However, one recent research study has cast doubt on the veracity of this belief.[53][54] In Bulgarian, Czech, German, Hungarian, Polish, Russian, Slovak and Swedish folklore the magpie is seen as a thief. In Hungary there is an old saying which said when you heard a magpie singing it meant guests would be coming to your house.[55][56][57] Perhaps because the magpie loved to sit on the trees in front of the village houses and signaled when a man was approaching.[58]
In Sweden, it is further associated with witchcraft.[49] In Norway, a magpie is considered cunning and thievish, but also the bird of hulder, the underground people.[59]
Magpies have been attacked for their role as predators, which includes eating other birds' eggs and their young. However, one study has disputed the view that they affect total song-bird populations, finding "no evidence of any effects of [magpie] predator species on songbird population growth rates. We therefore had no indication that predators had a general effect on songbird population growth rates".[60] Another study has claimed that songbird populations increased in places where magpie populations were high and that they do not have a negative impact on the total song-bird population.[61]
1 2 Emery, N.J.; Clayton, N.S. (2004). "Comparing the complex cognition of birds and primates". In Rogers, L.J.; Kaplan, G.T. (eds.). Comparative vertebrate cognition: are primates superior to non-primates?. New York: Kluwer Academic. pp.9, 3–56. ISBN978-0-306-47727-0.
1 2 3 Blake, Emmet R.; Vaurie, Charles (1962). "Family Corvidae, Crows and Jays". In Mayer, Ernst; Greenway, James C. Jr. (eds.). Check-list of Birds of the World. Vol.15. Cambridge, Massachusetts: Museum of Comparative Zoology. pp.250–254.
↑ Gill, Frank; Donsker, David (eds.). "Crows, mudnesters & birds-of-paradise". IOC World Bird List Version 8.2. International Ornithologists' Union. Retrieved 20 July 2018.
↑ Zhang, R.; etal. (2012). "Comparative phylogeography of two widespread magpies: Importance of habitat preference and breeding behavior on genetic structure in China". Molecular Phylogenetics and Evolution. 65 (2): 562–572. doi:10.1016/j.ympev.2012.07.011. PMID22842292.
1 2 Snow, D.W.; Perrins, C.M., eds. (1998). The Birds of the Western Palearctic. Vol.2 Passerines (Conciseed.). Oxford: Oxford University Press. pp.1457–1460. ISBN978-0-19-850188-6.
1 2 3 4 5 6 Madge, S. (2009). "Common Magpie (Pica pica)". In del Hoyo, J.; Elliott, A.; Sargatal, J.; Christie, D.A.; de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions.
↑ Leszek, Jerzak (2001). "Synurbanization of the magpie in the Palearctic". In Marzluff, J.; Bowman, R.; Donnelly, R. (eds.). Avian ecology and conservation in an urbanizing world. Boston: Kluwer Academic Publishers. pp.403–425. ISBN978-0-7923-7458-9.
↑ Antonov, A.; Atanasova, D. (2002). "Nest-site selection in the magpie Pica pica in a high-density urban population of Sofia (Bulgaria)". Acta Ornithologica. 37 (2): 55–66. doi:10.3161/068.037.0201.
↑ Holden, Peter (2012). RSPB Handbook Of British Birds. Christopher Helm. p.270. ISBN978-1-4081-2735-3.
↑ Bekoff, M. (2009). "Animal emotions, wild justice and why they matter: Grieving magpies, a pissy baboon, and empathic elephants". Emotion, Space and Society. 2 (2): 1–4. doi:10.1016/j.emospa.2009.08.001.
↑ de Waal, Frans (2009). The Age of Empathy: Nature's Lessons for a Kinder Society. New York: Harmony Books. p.149.
↑ Robertson, Joyce (2010). Meet the Magpie. AuthorHouse. p.5. ISBN9781449087913.
↑ Winterman, Denise (2008-03-28). "Why are magpies so often hated?". BBC News Magazine. Magpies have a dubious reputation because they are a bit of both. Over the years they have been lumped in with blackbirds
↑ Tickner, Lisa (1980). "One for Sorrow, Two for Mirth: The Performance Work of Rose Finn-Kelcey". Oxford Art J. 3 (1): 58–73. doi:10.1093/oxartj/3.1.58.
1 2 3 Brewer, E.C. (1970). Brewer's Dictionary of Phrase and Fable. rev. by Ivor H. Evans (centenaryed.). London: Cassell. p.674.
↑ "skjære – folketro"[magpie – folklore]. Store Norske Leksikon [Norwegian Encyclopedia] (in Norwegian). 2017-02-22.
↑ Stoate, C.; Thomson, D.L. (2000). "Predation and songbird populations"(PDF). In Aebischer, N.J.; Evans, A.D.; Grice, P.V.; Vickery, J.A. (eds.). Ecology and Conservation of Lowland Farmland Birds. Tring, England: British Ornithologists' Union. pp.134–139. ISBN978-0-907446-24-8. Archived from the original(PDF) on 2017-07-14. Retrieved 2015-06-10.
↑ Gooch, S.; Baillie, S.R.; Birkhead, T.R. (1991). "Magpie Pica pica and songbird populations. Retrospective investigation of trends in population density and breeding success". Journal of Applied Ecology. 28 (3): 1068–1086. Bibcode:1991JApEc..28.1068G. doi:10.2307/2404226. JSTOR2404226.
Cited sources
Birkhead, T. R. (1991). The Magpies: The Ecology and Behaviour of Black-Billed and Yellow-Billed Magpies. T. & A.D. Poyser. ISBN978-085661067-7.
Magpies are birds of the family Corvidae. Like other members of their family, they are widely considered to be intelligent creatures. The Eurasian magpie, for instance, is thought to rank among the world's most intelligent creatures and is one of the few nonmammalian species able to recognize itself in a mirror test. Magpies have shown the ability to make and use tools, imitate human speech, grieve, play games, and work in teams. They are particularly well known for their songs and were once popular as cagebirds. In addition to other members of the genus Pica, corvids considered as magpies are in the genera Cissa, Urocissa, and Cyanopica.
Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, ravens, rooks, magpies, jackdaws, jays, treepies, choughs, and nutcrackers. In colloquial English, they are known as the crow family or corvids. Currently, 135 species are included in this family. The genus Corvus containing 47 species makes up over a third of the entire family. Corvids (ravens) are the largest passerines.
The Australian magpie is a black and white passerine bird native to Australia and southern New Guinea, and introduced to New Zealand. Although once considered to be three separate species, it is now considered to be one, with nine recognised subspecies. A member of the Artamidae, the Australian magpie is placed in its own genus Gymnorhina and is most closely related to the black butcherbird. It is not closely related to the European magpie, which is a corvid.
The yellow-billed magpie(Pica nuttalli), also known as the California magpie, is a large corvid that inhabits California's Central Valley and the adjacent chaparral foothills and mountains. Apart from its having a yellow bill and a yellow streak around the eye, it is virtually identical to the black-billed magpie (Pica hudsonia) found in much of the rest of North America. The scientific name commemorates the English naturalist Thomas Nuttall.
The black-billed magpie, also known as the American magpie, is a bird in the corvid family found in the western half of North America. It is black and white, with the wings and tail showing black areas and iridescent hints of blue and blue-green. It was once thought to be a subspecies of the Eurasian magpie, but was placed into its own species in 2000 based on genetic studies.
The Australian raven is a passerine bird in the genus Corvus native to much of southern and northeastern Australia. Measuring 46–53 centimetres (18–21 in) in length, it has all-black plumage, beak and mouth, as well as strong grey-black legs and feet. The upperparts are glossy, with a purple, blue, or green sheen, and its black feathers have grey bases. The Australian raven is distinguished from the Australian crow species by its throat hackles, which are prominent in adult birds. Older adult individuals have white irises, younger adults have white irises with an inner blue rim, while younger birds have dark brown irises until fifteen months of age, and hazel irises with an inner blue rim around each pupil until age two years and ten months. Nicholas Aylward Vigors and Thomas Horsfield described the Australian raven in 1827, its species name (coronoides) highlighting its similarity with the carrion crow. Two subspecies are recognized, which differ slightly in calls and are quite divergent genetically.
The Torresian crow, also called the Australian crow or Papuan crow, is a passerine bird in the crow family native to the north and west of Australia and nearby islands in Indonesia and Papua New Guinea. The species has a black plumage, beak and mouth with white irises. The base of the feathers on the head and neck are white. The Torresian crow is slightly larger with a more robust bill than the morphologically similar little crow.
The forest raven, also commonly known as the Tasmanian raven, is a passerine bird in the family Corvidae native to Tasmania and parts of southern Victoria, such as Wilsons Promontory and Portland. Populations are also found in parts of New South Wales, including Dorrigo and Armidale. Measuring 50–53 cm (20–21 in) in length, it has all-black plumage, beak and legs. As with the other two species of raven in Australia, its black feathers have grey bases. Adults have white irises; younger birds have dark brown and then hazel irises with an inner blue rim. New South Wales populations are recognised as a separate subspecies C. tasmanicus boreus, but appear to be nested within the Tasmanian subspecies genetically.
The western jackdaw, also known as the Eurasian jackdaw, the European jackdaw, or simply the jackdaw, is a passerine bird in the crow family. Found across Europe, western Asia and North Africa; it is mostly resident, although northern and eastern populations migrate south in the winter. Four subspecies are recognised, which differ mainly in the colouration of the plumage on the head and nape. Linnaeus first described it formally, giving it the name Corvus monedula. The common name derives from the word jack, denoting "small", and daw, a less common synonym for "jackdaw", and the native English name for the bird.
The azure-winged magpie is a bird in the crow family. It is 31–35 cm long and similar in overall shape to the Eurasian magpie but is more slender with proportionately smaller legs and bill. It belongs to the genus Cyanopica.
The blue jay is a passerine bird in the family Corvidae, native to eastern North America. It lives in most of the eastern and central United States; some eastern populations may be migratory. Resident populations are also in Newfoundland, Canada; breeding populations are found across southern Canada. It breeds in both deciduous and coniferous forests, and is common in residential areas. Its coloration is predominantly blue, with a white chest and underparts, and a blue crest; it has a black, U-shaped collar around its neck and a black border behind the crest. Males and females are similar in size and plumage, and plumage does not vary throughout the year. Four subspecies have been recognized.
The red-billed blue magpie is a species of bird in the crow family, Corvidae. It is about the same size as the Eurasian magpie, but has a much longer tail, one of the longest of any corvid. It is 65–68 cm (25.5–27 in) long and weighs 196–232 g (6.9–8.2 oz).
The Eurasian chaffinch, common chaffinch, or simply the chaffinch is a common and widespread small passerine bird in the finch family. The male is brightly coloured with a blue-grey cap and rust-red underparts. The female is more subdued in colouring, but both sexes have two contrasting white wing bars and white sides to the tail. The male bird has a strong voice and sings from exposed perches to attract a mate.
The Eurasian sparrowhawk, also known as the northern sparrowhawk or simply the sparrowhawk, is a small bird of prey in the family Accipitridae. Adult male Eurasian sparrowhawks have bluish grey upperparts and orange-barred underparts; females and juveniles are brown above with brown barring below. The female is up to 25% larger than the male – one of the greatest size differences between the sexes in any bird species. Though it is a predator which specialises in catching woodland birds, the Eurasian sparrowhawk can be found in any habitat and often hunts garden birds in towns and cities. Males tend to take smaller birds, including tits, finches, and sparrows; females catch primarily thrushes and starlings, but are capable of killing birds weighing 500 g (18 oz) or more.
The razorbill, razor-billed auk, or lesser auk is a North Atlantic colonial seabird and the only extant member of the genus Alca of the family Alcidae, the auks. It is the closest living relative of the extinct great auk.
The great spotted cuckoo is a member of the cuckoo order of birds, the Cuculiformes, which also includes the roadrunners, the anis and the coucals.
The Siberian jay is a small jay with a widespread distribution within the coniferous forests in North Eurasia. It has grey-brown plumage with a darker brown crown and a paler throat. It is rusty-red in a panel near the wing-bend, on the undertail coverts and on the sides of the tail. The sexes are similar. Although its habitat is being fragmented, it is a common bird with a very wide range so the International Union for Conservation of Nature has assessed its conservation status as being of "least concern".
The black-throated magpie-jay is a strikingly long-tailed magpie-jay of northwestern Mexico.
The Iberian magpie is a bird in the crow family. It is 31–35 cm (12–14 in) long and similar in overall shape to the Eurasian magpie but is slenderer with proportionately smaller legs and bill. It belongs to the genus Cyanopica.
The Asir magpie, also known as the Arabian magpie, is a highly endangered species of magpie endemic to Saudi Arabia. It is only found in the country's southwestern highlands, in the Asir Region. It occurs only in African juniper forest in well-vegetated wadis and valleys. It was formerly classified as a subspecies of the Eurasian magpie, and still is by many authorities. This species is highly threatened by habitat destruction, as its native forests are not regenerating. Tourism development and climate change are also posing a threat. Only 135 pairs are known to survive in the wild, and this number is declining.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
