Common Teal
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 Male in nuptial plumage
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| Anas crecca Linnaeus, 1758 |
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 Global distribution of the Common Teal in Europe and Asia and the Green-winged Teal in North America
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The Common Teal or simply Teal (Anas crecca) is a common and widespread duck which breeds in the northernmost areas of Europe and Asia. It is the Old World counterpart of the North American Green-winged Teal, Anas carolinensis, with which it is sometimes considered conspecific.
For example, the issue is still being reviewed by the AOU[1]. Based on this the IUCN and BirdLife International (BirdLife International, 2004, 2006) do not accept it as a separate species at present. However, nearly all other authorities consider it distinct nowadays, based on behavioral (Laurie-Ahlberg & McKinney 1979), morphological (Livezey, 1991), and molecular (Johnson & Sorenson 1999) evidence (discussed by Sangster et al., 2002). See the Green-winged Teal page for a discussion of the species' phylogeny.
This dabbling duck is strongly migratory and winters south to Africa and south Asia. It highly gregarious outside of the breeding season and will form large flocks. In flight, the fast, twisting flocks resemble waders.
This is the smallest dabbling duck at 34-38 cm length with a 53-59 cm wingspan. The breeding male has grey flanks and back, with a yellow rear end and a white-edged green speculum, obvious in flight or at rest. It has a chestnut head with a green eye patch. It is distinguished from drake Green-winged Teal by a horizontal white scapular stripe, no vertical white bar on side of breast, and thin buff lines on its head.
The females are light brown, with plumage much like a female Mallard. They can be distinguished from most ducks on size and shape, and the speculum. Separation from female Green-winged Teal is problematic.
In non-breeding (eclipse) plumage, the drake looks more like the female.
It is a common inhabitant of sheltered wetlands with some taller vegetation, such as taiga bogs in the breeding season. The Common Teal usually feeds by dabbling for plant food or grazing. It nests on the ground, near water and under cover.
This is a noisy species. The male has a clear whistle, whereas the female has a feeble "quack".
It is found throughout the United Kingdom, where it is often known simply as "the Teal". However its main status there is of a winter visitor from Siberia, with a few stopping at favoured spots to breed, as well as a summer visiting only population in the Scottish Highlands. In winter, they also occur in high densities in Japan, Taiwan and possibly Mauretania and the Nile Valley. Altogether though, the Common Teal is much rarer than its American counterpart (though still very plentiful). It appears to be holding its own for the time being, with slow decline of maybe 1-2% annually over the last decade (Carboneras, 1992; BirdLife International, 2006) not warranting action except for continuing monitoring and possibly more reserves on the wintering grounds even if considered a separate species. The IUCN and BirdLife International classify the red-and-green-headed teals as one species of Least Concern; the latter still applies for both if they are split.
The Common Teal is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies. It is listed on CITES Annex III in Ghana[verification needed].
[edit] References
- BirdLife International (2005). Anas crecca. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 09 May 2006. Database entry includes justification for why this species is of least concern
- BirdLife International (2006): Species factsheet: Anas crecca. Retrieved 14-NOV-2006.
- Carboneras, Carles (1992): Family Anatidae (Ducks, Geese and Swans). In: del Hoyo, Josep; Elliott, Andrew & Sargatal, Jordi (editors): Handbook of Birds of the World, Volume 1: Ostrich to Ducks: 536-629. Lynx Edicions, Barcelona. ISBN 84-87334-10-5
- Johnson, K. P. & Sorenson, M. D. (1999): Phylogeny and biogeography of dabbling ducks (genus Anas): a comparison of molecular and morphological evidence. Auk 116(3): 792–805. PDF fulltext
- Laurie-Ahlberg, C. C. & McKinney, F. (1979): The nod-swim display of male Green-winged Teal (Anas crecca). Animal Behaviour 27: 165–172. DOI:10.1016/0003-3472(79)90136-2 (HTML abstract)
- Livezey, B. C. (1991): A phylogenetic analysis and classification of recent dabbling ducks (Tribe Anatini) based on comparative morphology. Auk 108(3): 471–507. PDF fulltext
- Sangster, George; Knox, Alan G.; Helbig, Andreas J. & Parkin, David T. (2002): Taxonomic recommendations for European birds. Ibis 144(1): 153–159. DOI:10.1046/j.0019-1019.2001.00026.x PDF fulltext
