Bombycilla garrulus
Bohemian waxwing

Bohemian waxwings are native to the Nearctic and Palearctic regions. Their range during times of breeding in the Nearctic region spans as far west as central Alaska and as far east as the central part of Ontario. Most breeding regions do not extend any farther south than the most southern part of British Columbia. They normally do not breed north of Alaska or Nova Scotia. In March and April, this species migrates south to southwest British Columbia and the northern United States. In the Palearctic region breeding occurs in the northern parts of Eurasia, most commonly in Scandinavia, Russia and Siberia. These populations migrate south to central Europe and east to central Japan in the non-breeding season. (Witmer, 2002)

During the breeding season, Bohemian waxwings are most common in woodlands ranging from coniferous to coniferous-deciduous. This species also inhabits areas around lakes, streams, and swamps. Typically, they inhabit areas where they can forage for fruits and insects in plentiful amounts. During spring and fall migration they abandon woodlands to seek areas high in fruit abundance, including urban habitats. When food resources diminish, they relocate. During winter seasons, Bohemian waxwings are found in woodland or scrub areas with fruit that remains on branches. (Ehrlich, Dobkin, and Wheye, 1988; Witmer, 2002)

Bohemian waxwings are described as starling-sized, having sleek crests, gray overall, with face washed in chestnut. The tip of the tail has a yellow band. Adult males have a throat patch that is larger than that of females and a broader yellow tip to the tail. The common name, "waxwing," comes from the red waxy tips on their secondary feathers. A similar species, cedar waxwings (Bombycilla cedrorum), are smaller, having a pale yellow belly, and wings that are not as colorful. Juvenile Bohemian waxwings have plumage that is more gray than that of adults, with a whitish throat, and streaked underparts. (Alderfer, 2006; Tyne and Berger, 1976; Witmer, 2002)

The longest reported lifespan for a banded bird in North America was 5 years 10 months. This species is recorded living as long as 12 years in Europe. The main causes of mortality are predation, competition between similar species, and failure to fully metabolize ethanol produced from the consumption of fruits (intoxication). (Witmer, 2002)

Bohemian waxwings are often seen fluttering from perch to perch in shrubs and trees. They rarely walk on the ground. Bohemian waxwings perform self-maintenance by scratching the head with a foot over a partially extended wing, they also bathe in shallow puddles that gather from rainfall. The only form of behavioral aggression noted in Bohemian waxwings is mate-guarding. Male Bohemian waxwings will ward off other intruders attempting courtship-hopping with their paired female. Males adopt a threat posture and uses their bill to snap at intruders. Bohemian waxwings are found mainly in flocks that travel together to forage and in migration. They use calls constantly as a form of social cohesion, call volume increases when the flock is about to depart. Most flocks are between 50 and 300 birds, but some have been recorded at over 3000. Flocks exhibit "gift-passing," in which birds pass fruit to their flock mates for consumption. (Witmer, 2002)

Home Range

Bohemian waxwings are not territorial. Even at the nest, males are not aggressive unless another male approaches to court their mate. Nests are often clumped and found at highest densities near fruiting shrubs and trees. (Witmer, 2002)

Bohemian waxwings usually communicate through vocalizations, similar to their close relatives, cedar waxwings. Social calls are described as a trilling "zeee". Hatchlings also use a quiet trill with parents. The basic call is a high pitched, rapid trill that has a variety of frequencies and is generally lower in pitch than that of cedar waxwings When mates are within range of each other contact calls are used. These are normally softer and higher in pitch than the social call. A courtship call consists of a very wide frequency spread. Both mates give courtship calls during nest-building and courtship interaction. Females continue to give courtship calls while feeding and sitting in the nest. A disturbance call is normally characterized by a long descending whistle. The disturbance call is used during nest-building and incubation. No injury or begging calls have been reported in Bohemian waxwings. (Alderfer, 2006; Witmer, 2002)

Bohemian waxwings are frugivorous and insectivorous. The main source of food is sugary fruits. Bohemian waxwings have a large liver which helps convert sugar to energy. They also have the ability to metabolize ethanol from the fermentation of those sugary fruits. Favorite fruits in North America include juniper (Juniperus virginiana) and mountain ash (Sorbus americana). Bohemian waxwings also feed on aerial insects during the summer. In late spring and early summer insects, especially midges (Chironomidae) and mosquitos (Culicidae), make up about 37% of their diet. Insects are also favored during nesting. When preferred food sources are less abundant, they feed on flowers and sap from trees. (Baughman, 2003; Burton and Kress, 2005; Witmer, 2002)

Bohemian waxwings are preyed on mainly by birds of prey, including merlins (Falco columbarius), which prey extensively on winter flocks, prairie falcons (Falco mexicanus), rough-legged hawks (Buteo lagopus), and Eurasian sparrowhawks (Accipiter nisus). When approached, Bohemian waxwings adopt a cryptic posture with neck and bill extended skyward while they remain very still. If the cryptic posture fails to be effective, they fly upward and chatter loudly to warn other waxwings of a threat. (Witmer, 2002)

Bohemian waxwings are preyed on by falcons and hawks. They are important seed dispersers and prey on small, flying insects. There are 2 types of protozoan parasites documented in Bohemian waxwings: Leucocytozoon and Trypanosoma. (Stabler and Kitzmiller, 1970; Witmer, 2002)

There are no known adverse effects of Bohemian waxwings on humans.

Bohemian waxwings are sought after by bird watchers and they provide important ecosystem services by dispersing the seeds of the fruiting trees and shrubs they eat. (Witmer, 2002)

Bohemian waxwing populations are increasing due to conservation of shrub lands in the United States. Some of the problems facing Bohemian waxwing populations are collisions with windows, automobile collisions, and the toxic effects of pesticides. (Baughman, 2003; Witmer, 2002)