Seidenschwanz

Bestimmung

The Bohemian waxwing is a starling-sized bird 19–23 cm (7.5–9.1 in) in length with a 32–35.5 cm (12.6–14.0 in) wingspan, and an average weight of 55 g (1.9 oz). It is short-tailed, mainly brownish-grey, and has a conspicuous crest on its head. The male of the nominate subspecies has a black mask through the eye and a black throat. There is a white streak behind the bill and a white curve below the eye. The lower belly is a rich chestnut colour and there are cinnamon-coloured areas around the mask. The rump is grey and the tail ends in a bright yellow band with a broad black border above it. The wings are very distinctive; the flight feathers are black and the primaries have markings that produce a yellow stripe and white "fishhooks" on the closed wing. The adult's secondaries end in long red appendages with the sealing wax appearance that gives the bird its English name. The eyes are dark brown, the bill is mainly black, and the legs are dark grey or black. In flight, the waxwing's large flocks, long wings and short tail give some resemblance to the common starling, and its flight is similarly fast and direct. It clambers easily through bushes and trees but only shuffles on the ground.<p>The soft, dense feathers are kept in good condition by preening. The red waxy tips are the extended and flattened ends of feather shafts, pigmented with astaxanthin and enclosed in a transparent sheath. A study of the cedar waxwings showed that the red tips are few or absent until the third year of life for that related species. All adult waxwings have a complete moult annually between August and January. Juveniles moult at the same time but retain their flight and some other wing feathers.<p>The female Bohemian waxwing is very similar to the male, but has a narrower yellow terminal band to the tail, a less defined lower edge to the black throat and slightly less distinctive wing markings. Juveniles are duller than adults, with whiter underparts, only a few red wing tips, no black on the throat and a smaller black face mask. Compared to the nominate subspecies, eastern B. g. centralasiae is paler, greyer and has little reddish-brown behind the bill. The American subspecies B. g. pallidiceps has more colouring on the cheeks and forehead than the nominate form and is otherwise generally duller in appearance.<p>The range of the Bohemian waxwing overlaps those of both the other members of the genus. The cedar waxwing is smaller than the Bohemian; it has browner upperparts, a white undertail and a white line above the black eye patch. Adult cedar waxwings have a yellowish belly, and all ages have less strongly patterned wings than the Bohemian waxwing. The Japanese waxwing is easily distinguished from its relatives; it has a red terminal band to the tail, the black mask extends up the rear of the crest, and there is no yellow stripe or red tips on the wings.<p>The Bohemian waxwing's call is a high trill sirrrr. It is less wavering and lower-pitched than that of the cedar waxwing, and longer and lower-pitched than the call of the Japanese waxwing. Other calls are just variants of the main vocalisation; a quieter version is used by chicks to call parents, and courtship calls, also given during nest construction, have a particularly large frequency range. Although not a call as such, when a flock takes off or lands, the wings make a distinctive rattling sound that can be heard 30 m (98 ft) away.

Taxonomie

The waxwings are a family, Bombycillidae, of short-tailed stocky birds with soft plumage, a head crest and distinctively patterned wings and tails. There are three species, the Bohemian, cedar, and Japanese waxwings. DNA studies and shared features such as a relatively large size, grey underparts and similar undertail patterns suggest that the Japanese and Bohemian waxwings are most closely related within the genus. Although only the cedar and Bohemian waxwings normally have red tips on their wing feathers, this feature is occasionally shown by the Japanese waxwing, suggesting that this was originally a whole-family characteristic that has been lost in one species, rather than an indicator of a close relationship. DNA analysis confirms that the cedar waxwing diverged early from the other members of the family. Outside the genus, the closest relatives of the waxwings are believed to be the silky-flycatchers, the palmchat, and the grey hypocolius, all of which have sometimes been included in the Bombycillidae.<p>The Bohemian waxwing was described by Carl Linnaeus in his 1758 10th edition of Systema Naturae as Lanius Garrulus. The waxwings were moved to their own genus, Bombycilla, by Louis Pierre Vieillot in 1808. The genus name Bombycilla comes from the Greek bombux, "silk" and the Modern Latin cilla, "tail"; this is a direct translation of the German Seidenschwanz, "silk-tail", and refers to the silky-soft plumage of the bird. The species name garrulus is the Latin for talkative and was applied to this bird, as "Garrulus Bohemicus", by Conrad Gessner in 1555; the term is a reference to a supposed likeness to the Eurasian jay (Garrulus glandarius) rather than to the waxwing's vocalisations. The English name "waxwing" refers to the bright red tips of the secondary feathers on its wings, which look like drops of sealing wax, while "Bohemian" follows Gessner's usage, and may refer to the Romani, alluding to the bird's wanderings, or to its presumed origin from Bohemia. "Waxwing" and "Bohemian waxwing" were first recorded in 1817, the former as a reference to Vieillot's separation of this bird from the "chatterers".<p>There are three recognised subspecies:<p>The differences between these forms are small and clinal, and the species could be possibly considered as monotypic. The fossil record includes Pleistocene deposits from the UK and the Carpathian Mountains.

Wissenschaftlicher Name

Bombycilla garrulus

Autorität

(Linnaeus, 1758)

Ordnung

Passeriformes

Familie

Seidenschwänze

Gattung

Bombycilla

Verbreitung und Lebensraum

The Bohemian waxwing has a circumpolar distribution, breeding in northern regions of Eurasia and North America. In Eurasia, its northern nesting limit is just short of the treeline, roughly at the 10 °C July isotherm, and it breeds south locally to about 51°N. Most birds breed between 60–67°N, reaching 70°N in Scandinavia. The North American subspecies breeds in the northwestern and north central areas of the continent, its range extending southwards beyond the US border in the Rocky Mountains.<p>This waxwing is migratory with much of the breeding range abandoned as the birds move south for the winter. Migration starts in September in the north of the range, a month or so later farther south. Eurasian birds normally winter from eastern Britain through northern parts of western and central Europe, Ukraine, Kazakhstan and northern China to Japan. North American breeders have a more southeasterly trend, many birds wintering in southeast Canada, with smaller numbers in the north central and northeastern US states. Birds do not usually return to the same wintering sites in successive years. One bird wintering in the Ukraine was found 6,000 km (3,700 mi) to the east in Siberia in the following year.<p>In some years, this waxwing irrupts south of its normal wintering areas, sometimes in huge numbers. The fruit on which the birds depend in winter varies in abundance from year to year, and in poor years, particularly those following a good crop the previous year, the flocks move farther south until they reach adequate supplies. They will stay until the food runs out and move on again. In what may be the largest ever irruption in Europe, in the winter of 2004–2005, more than half a million waxwings were recorded in Germany alone. This invasion followed an unusually warm, dry breeding season. In 1908, an American flock 60–90 m (200–300 ft) wide was noted as taking two to three minutes to fly over.<p>The breeding habitat is mature conifers, often spruce although other conifers and broadleaf trees may also be present. More open, wet areas such as lakes and peat swamps with dead and drowned trees are used for feeding on insects. Lowlands, valleys and uplands are used in Eurasia, although mountains tend to be avoided. However, the North American subspecies nests in Canada at altitudes between 900–1,550 m (2,950–5,090 ft). Outside the breeding season, the waxwing will occupy a wide range of habitats as long as suitable fruits such as rowan are available. It may be found by roads, in parks and gardens or along hedges or woodlands edges. It shows little fear of humans at this time. In winter, waxwings roost communally in dense trees or hedges, sometimes with American robins, fieldfares or other wintering species.

Zugverhalten

Vollzieher

Verhalten

Zugverhalten: Vollzieher.

Schutzstatus

Bestandstrend: zunehmend.

Bestandstrend

zunehmend