Eurasian teal | |
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Wintering male from Mangaon, Maharashtra, India | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Anseriformes |
Family: | Anatidae |
Genus: | Anas |
Species: | A. crecca |
Binomial name | |
Anas crecca | |
Distribution map light green : nesting area blue : wintering area dark green : resident all year | |
Synonyms | |
Anas crecca crecca Linnaeus, 1758 Contents |
The Eurasian teal (Anas crecca), common teal, or Eurasian green-winged teal is a common and widespread duck that breeds in temperate Eurosiberia and migrates south in winter. [2] The Eurasian teal is often called simply the teal due to being the only one of these small dabbling ducks in much of its range. [3] The bird gives its name to the blue-green colour teal.
It is a highly gregarious duck outside the breeding season and can form large flocks. It is commonly found in sheltered wetlands and feeds on seeds and aquatic invertebrates. The North American green-winged teal (A. carolinensis) was formerly (and sometimes is still) considered a subspecies of A. crecca.
The Eurasian teal belongs to the "true" teals, a group of small Anas dabbling ducks closely related to the mallard (A. platyrhynchos) and its relatives; that latter group in fact seems to have evolved from a true teal. It forms a superspecies with the green-winged teal and the speckled teal (A. flavirostris). A proposed subspecies, A. c. nimia of the Aleutian Islands, differs only in slightly larger size; it is probably not distinct. [3] [4] [5]
Whether the Eurasian and green-winged teals are to be treated as one or two species is still being reviewed by the American Ornithologists' Union, [6] while the International Union for Conservation of Nature and BirdLife International separate them nowadays. [1] Despite the almost identical and highly apomorphic nuptial plumage of their males, which continues to puzzle scientists, they seem well distinct species, as indicated by a wealth of behavioural, morphological, and molecular data. [4] [5] [7] [8]
The Eurasian teal was first scientifically named by Carl Linnaeus in his 1758 edition of Systema naturae . His Latin description reads: [Anas] macula alarum viridi, linea alba supra infraque oculos – "a duck with green speculum, a white line above and below the eyes" – and his primary reference was the bird's description in his earlier work Fauna Svecica. [9] In fact, the description he used in Systema Naturae was the name under which the bird went in the Fauna Svecica, demonstrating the value of his new binomial nomenclature by compressing the long-winded names formerly used in biological classification into much simpler scientific names like Anas crecca. Linnaeus also noted in his description that earlier authors had already written about the Eurasan teal at length: Conrad Gessner [10] had described it in the Historiae animalium as the anas parva ("small duck") among his querquedulae ("teals"); Ulisse Aldrovandi [11] had called it phascade or querquedula minor ("lesser teal"), and was duly referenced by Francis Willughby [12] who named the species querquedula secunda Aldrovandi ("the second teal of Aldrovandi" [note 1] ). John Ray [14] may be credited with formally introducing the name "common teal", while Eleazar Albin [15] called it simply "the teal". As regards the type locality Linnaeus simply remarked that it inhabits freshwater ecosystems in Europe. [13]
The scientific name is from Latin Anas, "duck" and kricka, the Swedish name for this species. [16] The specific name of Linnaeus is onomatopoetic, referring to the male's characteristic call which was already discussed by Linnaeus' sources.[ citation needed ] The scientific name of the Eurasian teal—unchanged since Linnaeus' time— therefore translates as "duck that makes cryc"; common names like the Bokmål krikkand, Danish krikand and German Krickente mean the same.
The Eurasian teal is one of the smallest extant dabbling ducks at 34–43 cm (13–17 in) length and with an average weight of 360 g (13 oz) in drake (males) and 340 g (12 oz) in hens (females). The wings are 17.5–20.4 cm (6.9–8.0 in) long, yielding a wingspan of 53–59 cm (21–23 in). The bill measures 3.2–4 cm (1.3–1.6 in) in length, and the tarsus 2.8–3.4 cm (1.1–1.3 in). [3] [17]
From a distance, the drakes in nuptial plumage appear grey, with a dark head, a yellowish behind, and a white stripe running along the flanks. Their head and upper neck is chestnut, with a wide and iridescent dark green patch of half-moon- or teardrop-shape that starts immediately before the eye and arcs to the upper hindneck. The patch is bordered with thin yellowish-white lines, and a single line of that colour extends from the patch's forward end, curving along the base of the bill. The breast is buff with small round brown spots. The center of the belly is white, and the rest of the body plumage is mostly white with thin and dense blackish vermiculations, appearing medium grey even at a short distance. The outer scapular feathers are white, with a black border to the outer vanes, and form the white side-stripe when the bird is in resting position. The primary remiges are dark greyish brown; the speculum feathers are iridescent blackish-green with white tips, and form the speculum together with the yellowish-white tips of the larger upperwing coverts (which are otherwise grey). The underwing is whitish, with grey remiges, dense dark spotting on the inner coverts and a dark leading edge. The tail and tail coverts are black, with a bright yellowish-buff triangular patch in the center of the coverts at each side. [17]
In non-breeding (eclipse) plumage, the drake looks more like the hen; it is more uniform in colour, with a dark head and vestigial facial markings. The hen itself is yellowish-brown, somewhat darker on wings and back. It has a dark greyish-brown upper head, hindneck, eyestripe and feather pattern. The pattern is dense short streaks on the head and neck, and scaly spots on the rest of the body; overall they look much like a tiny mallard (A. platyrhynchos) hen when at rest. The wings are coloured similar to the drake's, but with brown instead of grey upperwing coverts that have less wide tips, and wider tips of the speculum feathers. The hen's rectrices have yellowish-white tips; the midbelly is whitish with some dark streaking. [17]
Immatures are coloured much like hens, but have a stronger pattern. The downy young are coloured like in other dabbling ducks: brown above and yellow below, with a yellow supercilium. They are recognizable by their tiny size however, weighing just 15 g (0.53 oz) at hatching. [3] [17] [18]
The drake's bill is dark grey, in eclipse plumage often with some light greenish or brownish hue at the base. The bill of hens and immatures is pinkish or yellowish at the base, becoming dark grey towards the tip; the grey expands basewards as the birds age. The feet are dark grey in males and greyish olive or greyish-brown in females and immatures. The iris is always brown. [17]
Moults during summer. Male in eclipse resembles female, but with darker upperparts and grey bill. Flight feathers are moulted simultaneously and birds are flightless for up to 4 weeks. [19]
This is a noisy species. The male whistles cryc or creelycc, not loud but very clear and far-carrying. The female has a feeble keh or neeh quack. [17]
Males in nuptial plumage are distinguished from green-winged teals by the horizontal white scapular stripe, the lack of a vertical white bar at the breast sides, and the quite conspicuous light outlines of the face patch, which are indistinct in the green-winged teal drake. Males in eclipse plumage, females and immatures are best recognised by their small size, calls, and the speculum; they are hard to tell apart from the green-winged teal however. [17]
The Eurasian teal breeds across the Palearctic and mostly winters well south of its breeding range. However, in the milder climate of temperate Europe, the summer and winter ranges overlap. For example, in the United Kingdom and Ireland a small summer population breeds, but far greater numbers of Siberian birds arrive in winter. In the Caucasus region, western Asia Minor, along the northern shores of the Black Sea, and even on the south coast of Iceland and on the Vestmannaeyjar, the species can be encountered all year, too. [17]
In winter, there are high densities around the Mediterranean, including the entire Iberian Peninsula and extending west to Mauretania; on Japan and Taiwan; as well as in South Asia. Other important wintering locations include almost the entire length of the Nile Valley, the Near East and Persian Gulf region, the mountain ranges of northern Iran, and South Korea and continental East and Southeast Asia. More isolated wintering grounds are Lake Victoria, the Senegal River estuary, the swamps of the upper Congo River, the inland and sea deltas of the Niger River, and the central Indus River valley. Vagrants have been seen in inland Zaire, Malaysia, on Greenland, and on the Marianas, Palau and Yap in Micronesia; [20] they are regularly recorded on the North American coasts south to California and South Carolina, [17] including annual sightings on the island of Newfoundland. [21]
From tracking wintering teal in Italy, most individuals departed the wintering grounds between mid-February and March, using the Black-Sea-Mediterranean flyway to reach their breeding grounds, from central Europe to east of the Urals, by May. This slow migration is due to long stopovers near the start of migration, mainly in south-eastern Europe. [22]
Altogether, the Eurasian teal is much less common than its American counterpart, though still very plentiful. Its numbers are mainly assessed by counts of wintering birds; some 750,000 are recorded annually around the Mediterranean and Black Seas, 250,000 in temperate western Europe, and more than 110,000 in Japan. In 1990 and 1991, a more detailed census was undertaken, yielding over 210,000 birds wintering in Iran, some 109,000 in Pakistan, about 77,000 in Azerbaijan, some 37,000 in India, 28,000 in Israel, over 14,000 in Turkmenistan and almost 12,000 in Taiwan. It appears to be holding its own currently, with its slow decline of maybe 1–2% annually in the 1990s – presumably mainly due to drainage and pollution of wetlands – not warranting action other than continuing to monitor the population and possibly providing better protection for habitat on the wintering grounds. The IUCN and BirdLife International classify the Eurasian teal as a species of Least Concern, unchanged from their assessment before the split of the more numerous A. carolinensis. [1] [3] [17]
The Eurasian teal is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies.
This dabbling duck is highly gregarious outside of the breeding season and will form large flocks. In flight, the fast, twisting flocks resemble waders; despite its short legs, it is also rather nimble on the ground by ducks' standards. In the breeding season, it is a common inhabitant of sheltered freshwater wetlands with some tall vegetation, such as taiga bogs or small lakes and ponds with extensive reedbeds. In winter, it is often seen in brackish waters and even in sheltered inlets and lagoons along the seashore. [17]
The Eurasian teal usually feeds by dabbling, upending or grazing; it may submerge its head and on occasion even dive to reach food. In the breeding season it eats mainly aquatic invertebrates, such as crustaceans, insects and their larvae, molluscs and worms. In winter, it shifts to a largely granivorous diet, feeding on seeds of aquatic plants and grasses, including sedges and grains. Diurnal throughout the breeding season, in winter they are often crepuscular or even nocturnal feeders. [17]
It nests on the ground, near water and under cover. The pairs form in the winter quarters and arrive on the breeding grounds together, starting about March. The breeding starts some weeks thereafter, not until May in the most northernly locations. The nest is a deep hollow lined with dry leaves and down feathers, built in dense vegetation near water. After the females have started laying, the males leave them and move away for shorter or longer distances, assembling in flocks on particular lakes where they moult into eclipse plumage; they will usually encounter their offspring only in winter quarters. The clutch may consist of 5–16 eggs, but usually numbers 8–11; they are incubated for 21–23 days. The young leave the nest soon after hatching and are attended by the mother for about 25–30 days, after which they fledge. The drakes and the hens with young generally move to the winter quarters separately. After the first winter, the young moult into adult plumage. The maximum recorded lifespan – though it is not clear whether this refers to the common or the green-winged teal—was over 27 years, which is rather high for such a small bird. [17]
The pintail or northern pintail is a duck species with wide geographic distribution that breeds in the northern areas of Europe and across the Palearctic and North America. It is migratory and winters south of its breeding range to the equator. Unusually for a bird with such a large range, it has no geographical subspecies if the possibly conspecific duck Eaton's pintail is considered to be a separate species.
The northern shoveler, known simply in Britain as the shoveler, is a common and widespread duck. It breeds in northern areas of Europe and across the Palearctic and across most of North America, wintering in southern Europe, the Indian subcontinent, Southeast Asia, Central America, the Caribbean, and northern South America. It is a rare vagrant to Australia. In North America, it breeds along the southern edge of Hudson Bay and west of this body of water, and as far south as the Great Lakes west to Colorado, Nevada, and Oregon.
The gadwall is a common and widespread dabbling duck in the family Anatidae.
The Eurasian wigeon or European wigeon, also known as the widgeon or the wigeon, is one of three species of wigeon in the dabbling duck genus Mareca. It is common and widespread within its Palearctic range.
The American wigeon, also known as the baldpate, is a species of dabbling duck found in North America. Formerly assigned to Anas, this species is classified with the other wigeons in the dabbling duck genus Mareca. It is the New World counterpart of the Eurasian wigeon.
The mallard or wild duck is a dabbling duck that breeds throughout the temperate and subtropical Americas, Eurasia, and North Africa. It has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Argentina, Chile, Colombia, the Falkland Islands, and South Africa. This duck belongs to the subfamily Anatinae of the waterfowl family Anatidae. Males (drakes) have green heads, while the females (hens) have mainly brown-speckled plumage. Both sexes have an area of white-bordered black or iridescent purple or blue feathers called a speculum on their wings; males especially tend to have blue speculum feathers. The mallard is 50–65 cm (20–26 in) long, of which the body makes up around two-thirds the length. The wingspan is 81–98 cm (32–39 in) and the bill is 4.4 to 6.1 cm long. It is often slightly heavier than most other dabbling ducks, weighing 0.7–1.6 kg (1.5–3.5 lb). Mallards live in wetlands, eat water plants and small animals, and are social animals preferring to congregate in groups or flocks of varying sizes.
The Green-winged Teal or American Teal is a common and widespread duck that breeds in the northern areas of North America except on the Aleutian Islands. It was considered conspecific with the Eurasian teal for some time, but the two have since been split into separate species. The American Ornithological Society continues to debate this determination; however, nearly all other authorities consider it distinct based on behavioral, morphological, and molecular evidence. The scientific name is from Latin Anas, "duck" and carolinensis, "of Carolina".
The blue-winged teal is a species of bird in the duck, goose, and swan family Anatidae. One of the smaller members of the dabbling duck group, it occurs in North America, where it breeds from southern Alaska to Nova Scotia, and south to northern Texas. It winters along the Pacific and Atlantic coasts and south into the Caribbean islands and Central America.
The garganey is a small dabbling duck. It breeds in much of Europe and across the Palearctic, but is strictly migratory, with the entire population moving to Africa, India, Bangladesh and Australasia during the winter of the Northern hemisphere, where large flocks can occur. This species was first described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae. Like other small ducks such as the Eurasian teal, this species rises easily from the water with a fast twisting wader-like flight.
The lesser scaup is a small North American diving duck that migrates south as far as Central America in winter. It is colloquially known as the little bluebill or broadbill because of its distinctive blue bill. The origin of the name scaup may stem from the bird's preference for feeding on scalp—the Scottish word for clams, oysters, and mussels; however, some credit it to the female's discordant scaup call as the name's source. It is apparently a very close relative of the Holarctic greater scaup or "bluebill", with which it forms a superspecies. The scientific name is derived from Ancient Greek aithuia an unidentified seabird mentioned by authors including Hesychius and Aristotle, and Latin, affinis "related to", from its resemblance to the greater scaup.
The Muscovy duck is a duck native to the Americas, from the Rio Grande Valley of Texas and Mexico south to Argentina and Uruguay. Feral Muscovy ducks are found in New Zealand, Australia, and in Central and Eastern Europe. Small wild and feral breeding populations have also established themselves in the United States, particularly in Florida, Louisiana, Massachusetts, the Big Island of Hawaii, as well as in many other parts of North America, including southern Canada.
The yellow-billed duck is a 51–58 cm long dabbling duck which is an abundant resident breeder in southern and eastern Africa. This duck is not migratory, but wanders in the dry season to find suitable waters. It is highly gregarious outside the breeding season and forms large flocks.
The cotton pygmy goose or cotton teal is a small perching duck which breeds in Asia, Southeast Asia extending south and east to Queensland where they are sometimes called white-quilled pygmy goose. They are among the smallest waterfowl in the world and are found in small to large waterbodies with good aquatic vegetation. They are usually seen in pairs or larger groups of pairs, roosting and nesting on trees near water. They are strong fliers and are known to disperse widely, especially in winter. Their breeding season coincides with the rains.
The Baikal teal, also called the bimaculate duck or squawk duck, is a dabbling duck that breeds in eastern Russia and winters in East Asia.
The falcated duck or falcated teal is a gadwall-sized dabbling duck from the east Palearctic.
The red-billed teal or red-billed duck is a dabbling duck which is an abundant resident breeder in southern and eastern Africa typically south of 10° S. This duck is not migratory, but will fly great distances to find suitable waters. It is highly gregarious outside the breeding season and forms large flocks.
The yellow-billed teal is a South American species of duck. Like other teals, it belongs to the diverse genus Anas; more precisely it is one of the "true" teals of subgenus Nettion. It occurs in Argentina, the Falkland Islands, Chile, Peru, Bolivia, Uruguay, and Brazil. It has also established itself in South Georgia, where it was first recorded breeding in 1971, and has been recorded as far east as Tristan da Cunha. It inhabits freshwater wetlands, preferring palustrine habitat to rivers. Considering its wide range and local abundance, it is not considered threatened by the IUCN.
The blue-billed teal, spotted teal or Hottentot teal is a species of dabbling duck of the genus Spatula. It is migratory resident in eastern and southern Africa, from Sudan and Ethiopia west to Niger and Nigeria and south to South Africa and Namibia. In west Africa and Madagascar it is sedentary.
The ringed teal is a small duck of South American forests. It is the only species of the genus Callonetta. Usually placed with the dabbling ducks (Anatinae), this species may actually be closer to shelducks and belong in the subfamily Tadorninae; its closest relative is possibly the maned duck.
The eastern spot-billed duck or Chinese spot-billed duck is a species of dabbling duck that breeds in East and Southeast Asia. This species was formerly considered a subspecies of the Indian spot-billed duck and both were referred to as the spot-billed duck. The name is derived from the yellow spot on the bill.