The Bohemian waxwing (Bombycilla garrulus) is a passerine bird that breeds in the northern forests of the Palearctic and North America. Its wings are patterned with white and bright yellow, and some feather tips have the red waxy appearance that give this species its English name. Waxwings can be very tame in winter and frequently enter towns and gardens in search of food, especially their favorite rowan berries.
The Bohemian waxwing 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 color and there are cinnamon-colored 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 a sealing wax appearance. The eyes are dark brown, the bill is mainly black, and the legs are dark grey or black. The soft, dense feathers are kept in good condition by preening. All adult waxwings have a complete molt annually between August and January. Juveniles molt at the same time but retain their flight and some other wing feathers. 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 coloring on the cheeks and forehead than the nominate form and is otherwise generally duller in appearance.
Bohemian waxwings have a circumpolar distribution, breeding in northern regions of Eurasia and North America. In winter, many waxwings desert their nesting range and migrate 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 winter in southeast Canada and smaller numbers in the north-central and northeastern US states. Bohemian waxwings breed in coniferous forests usually near wet areas such as lakes and peat swamps with dead and downed trees, and also lowlands, valleys, and uplands. They may occasionally be found in mixed forests. Outside the breeding season, waxwings will occupy a wide range of habitats as long as suitable fruits are available. They may be found by roads, in parks and gardens, or along hedges or woodland edges.
Bohemian waxwings are social birds. They forage in large flocks, sometimes of several hundred birds, and in winter roost communally in dense trees or hedges, sometimes with American robins, fieldfares, or other wintering species. Waxwings feed by day catching insects mainly by flycatching from an open perch, but may also pick their prey off vegetation. Fruits and berries are normally picked from trees, sometimes from the ground, and are usually swallowed whole. When alarmed, Bohemian waxwings "freeze" with their bill and neck pointing upwards. If this fails, they fly, calling noisily. The common call of these birds is a high trill 'sirrrr'. Other calls are just variants of the main vocalization; a quieter version is used by chicks to call parents, and courtship calls, also given during nest construction, have a particularly large frequency range.
Bohemian waxwings are herbivores (frugivores) and carnivores (insectivores). These birds are primarily fruit eaters and rowan berries are their favorite food. They also consume insects during the breeding season; mosquitoes and midges are the most common prey, but many other insects and some spiders are also eaten.
Bohemian waxwings are monogamous and form pairs. They start their return from the wintering grounds in February or March, but northern breeders do not reach their breeding areas until April or early May. Breeding occurs from mid-June to July. During this time males, perform courtship displays to attract females. The male erects his body and crest feathers and turns his head away from the female. He may repeatedly present a gift of a small item, often food, to his partner, placing it in her open bill. Older males have more red tips to the wings and are usually preferred by females. Bohemian waxwings are not highly territorial, and, although normally they nest solitary, several pairs may nest close together where there are several good nest sites. The nest is built by both sexes; it is a cup of thin twigs lined with softer material such as fine grass, moss, fur, or lichen. It is constructed 1.3-15 m (4-50 ft) above the ground in pine or scrub, commonly close to the trunk. The eggs are a glossy pale blue spotted with black and grey and the clutch is 3-7 eggs. The eggs are incubated for 13-14 days by the female alone. She is fed regurgitated berries by her mate and rarely leaves the nest. The chicks are altricial and naked, and have bright red mouths; they are fed by both parents, although the male brings most of the food, mainly insects, in the first few days. The young are subsequently fed largely with fruit. The chicks fledge about 14-16 days after hatching and are fed by the adults for another 2 weeks.
Bohemian waxwings are not considered threatened at present but they suffer from the use of pesticides in fruits and windows and automobile collisions.
According to the IUCN Red List, the global Bohemian waxwing population size is 14,400,000-28,150,000 mature individuals. The European population consists of 1,080,000-2,110,000 pairs, which equates to 2,160,000-4,220,000 mature individuals. Overall, currently, this species is classified as Least Concern (LC) on the IUCN Red List, and its numbers today are increasing.
Bohemian waxwings are important seed dispersers in their ecosystem. They travel significant distances when feeding and thus help to disperse the fruit seeds.
