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The Eurasian teal or common teal (Anas crecca) is a common and widespread duck which breeds in temperate Eurasia and migrates south in winter. 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. 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 breeds across northern Eurasia and mostly winters well south of its breeding range. However, in the milder climate oft emperate 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.
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; they are regularly recorded on the North American coasts south to California and South Carolina.
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.
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 reed beds. In winter, it is often seen in brackish waters and even in sheltered inlets and lagoons along the seashore.
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.
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.From Wikipedia, the free encyclopedia
Photos and video Athalassa by George Konstantinou
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