Wigeon (Anas penelope)

Wigeon

[order] ANSERIFORMES | [family] Anatidae | [latin] Anas penelope | [authority] Linnaeus, 1758 | [UK] Wigeon | [FR] Canard siffleur | [DE] Pfeifente | [ES] Anade Silbon | [NL] Smient

Subspecies

Monotypic species

Genus

Anas is a genus of dabbling ducks. It includes mallards, wigeons, teals, pintails and shovelers in a number of subgenera. Some authorities prefer to elevate the subgenera to genus rank.[1] Indeed, as the moa-nalos are very close to this clade and may have evolved later than some of these lineages, it is rather the absence of a thorough review than lack of necessity that this genus is rather over-lumped. The phylogeny of this genus is one of the most confounded ones of all living birds. Research is hampered by the fact the radiation of the two major groups of Anas ? the teals and mallard groups ? took place in a very short time and fairly recently, roughly in the mid-late Pleistocene. Furthermore, hybridization may have long played a major role in Anas evolution, with within-subgenus hybrids regularly and between-subgenus hybrids not infrequently being fully fertile.[1] The relationships between species are much obscured by this fact, and mtDNA sequence data is of dubious value in resolving their relationships; on the other hand, nuclear DNA sequences evolve too slowly to resolve the phylogeny of the subgenus Anas for example. Some major clades can be discerned. For example, that the traditional subgenus Anas, the mallard group, forms a monophyletic (in the loose sense, i.e. non-holophyletic) group has never been seriously questioned by modern science and is as good as confirmed (but see below). On the other hand, the phylogeny of the teals is very confusing. For these reasons, the dabbling duck lineages more distantly related to mallard group (which includes the type species of Anas) than the wigeons should arguably be separated in their own genera. These would include the Baikal Teal, the Garganey, the spotted black-capped Punanetta group, and the shovelers and other blue-winged species. Whether the wigeons, which are very distinct in morphology and behavior, but much less so in mtDNA cytochrome b and NADH dehydrogenase subunit 2 sequences, should also be considered a distinct genus Mareca (including the Gadwall and Falcated Duck) is essentially the one remaining point of dispute as regards the question which taxa should remain in this genus and which ones should not.

Physical charateristics

This winter visitor from Siberia is a close relative of the American Wigeon. The male Eurasian Wigeon in breeding plumage has a salmon-colored breast, pale gray body, and black undertail coverts. His head is dark rufous with a yellowish forehead. The wing has a green speculum with white coverts (the white is absent on the female), much like the American Wigeon. Juveniles and males in eclipse plumage (from July to September) look like the female. Female Eurasian and American Wigeons appear very similar, but the female Eurasian lacks the black border at the base of the bill. The main features that distinguish the Eurasian Wigeon from the American Wigeon are the gray sides and the russet face-markings. The Eurasian Wigeon hybridizes occasionally with the American Wigeon, and these birds, which show a mixture of characteristics, are seen in Washington with regularity.

Listen to the sound of Wigeon

[audio:http://www.planetofbirds.com/MASTER/ANSERIFORMES/Anatidae/sounds/Wigeon.mp3]

Copyright remark: Most sounds derived from xeno-canto


wingspan min.: 71 cm wingspan max.: 85 cm
size min.: 42 cm size max.: 50 cm
incubation min.: 24 days incubation max.: 25 days
fledging min.: 40 days fledging max.: 25 days
broods: 1   eggs min.: 7  
      eggs max.: 9  

Range

Eurasia : North

Habitat

When breeding, concentrated in boreal and subarctic zones with slight overlap into temperate and fairly numerous occurrences, often sporadic, in steppe zone. Prefers shallow, open, broad, fresh waters, of medium quality, neither strongly eutrophic nor oligotrophic, with ample submerged or floating vegetation but without dense, emergent or marginal stands. Predominantly lowland, within continental climatic zone; tolerant of open woodland and preferring wooded to open tundra, but thinning out towards dense forest and mountains. Uses good nesting cover in coniferous or deciduous wooded areas, as well as steppes, both near and fairly distant from water. Avoidance of extreme arctic climates permits early summer occupancy of breeding grounds and early departure, with rapid return movement in early autumn.
Winter habitat mainly in oceanic climates, lowland and largely maritime, especially along coasts where shallow, fairly sheltered waters and extensive tracts of tidal mud, sand, or salt-marsh offer sustenance and security for gatherings. Freshwater and brackish lagoons, and tracts of flooded grassland also attractive, and may be used in preference to coastal waters.

Reproduction

Eurasian Wigeons are known to breed only in Europe and Asia, although they are likely to be found breeding in North America eventually. They nest on the ground under dense vegetation, usually near water. The nest is a shallow depression lined with grass and down. The female incubates 8 to 9 eggs for 24 to 25 days. The young leave the nest and head for water shortly after hatching. They find their own food, although the female continues to tend them until they fledge at 40 to 45 days.

Feeding habits

Almost entirely vegetarian, mainly leaves, stems, stolons, bulbils, and rhizomes; also some seeds and occasionally animal materials. Obtained on land, by grazing while walking; on water, from surface; less often, under water by immersing head and neck.
The foraging strategies of the Eurasian Wigeon include picking food from the surface of shallow water, grazing in upland areas, and feeding on vegetation brought up by coots and diving ducks.

Video Wigeon

httpv://www.youtube.com/watch?v=PwbEjwPENlA

copyright: youtube


Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Anas penelope breeds in northern Europe, and winters in coastal areas of the Mediterranean, the Black Sea and north-west Europe, which together probably hold >50% of its global population. Its European wintering population is very large
(>1,700,000 individuals), and underwent a moderate increase between 1970-1990. Although there were substantial declines in Spain and Azerbaijan during 1990-2000, wintering populations were stable or increased across the rest of Europe, and the species was probably stable overall.
Except for Scotland, where it is sedentary, in the European Union (12 Members States) it is only known as a passage migrant or wintering bird. The population wintering around the North Sea is totalling 1250000 individuals, and is definitely increasing. These birds originate from Scandinavia and European Russia. Normally they don’t move farther south as Bretagne, but during strong winters they reach Spain in large numbers. The population wintering in the Black Sea and Mediterranean regions is estimated at 560000 individuals, and is declining. These birds probably have a more eastern origin, and are less subjected to spectacular winter movements.
Wigeon status Least Concern

Migration

This species is ighly migratory, except for some local resident populations in west Europe. A few resident populations exist Iceland and Scotland, but most winter Ireland and Britain. Smaller numbers reaching other North Sea countries, France, and Iberia. British breeders apparently mostly resident or make short south-west movements. Breeding populations of Fenno-Scandia and Russia migrate east to lower Yenisey basin and south to winter quarters in west and south-west Europe. Annually and very frequently wintering in Germany, Netherlands, Britain, Ireland, France, and to lesser extent Iberia. Those breeding west and central Siberia winter on Caspian and Black Seas. Also west to Mediterranean, especially Turkey, Greece, north Italy, and south France. Those reaching north Africa (notably Tunisia) are probably also from west-central Siberian population.
Moult migration reported from widely separated areas. Males leave breeding grounds early and move to moulting localities where they join the immature non-breeders. European moult gatherings are notably in Estonia, south Sweden, Denmark and the Netherlands. Typically the species forms flocks in August. Mass departures from breeding areas occur in September, main arrivals in the winter quarters mostly in October-November. Departure from North and Black Seas from mid-March to early April, but earlier in mild winters.

Distribution map

Wigeon distribution range map

Literature

Title Constraints of feeding on Salicornia ramosissimaby wigeon
Anas penelope: an experimental approach
Author(s): Daphne Durant, Marcel Kersten, Herve Fritz
Abstract: The coastal marshes of the Charente-Maritime (west..[more]..
Source: J Ornithol (2006) 147: 1-12

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Title Variation of pecking rate with sward height in wild wigeon Anas penelope
Author(s): Daphne Durant, Herve Fritz
Abstract: We examined how pecking rate changed with sward he..[more]..
Source: J Ornithol (2006) 147: 367-370

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Title Feeding behaviour of breeding Wigeon Anas penelope in relation to seasonal emergence and swarming behaviour of chironomids.
Author(s): Jacobsen O.W.
Abstract: Emergence of chironomids started in mid-April, and..[more]..
Source: ARDEA 79 (3): 409-418.

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Title Re-mating in migratory Wigeon Anas penelope
Author(s): Mitchell C.
Abstract: This note describes re-mating in migratory Wigeon ..[more]..
Source: ARDEA 85 (2): 275-277.

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