The Bohemian waxwing, scientifically known as Bombycilla garrulus, is a small songbird that belongs to the passerine group of birds. These birds are found in the northern forests of both the Palearctic region and North America. With a size similar to that of a starling, they possess distinctive features such as buff-grey plumage, striking black face markings, and a pointed crest on their heads. One of their most notable characteristics is their wings, which display intricate patterns of white and vibrant yellow. Additionally, some of their wing feathers exhibit a unique pink waxy appearance, from which the species derives its name in English. This article will give an overview of Bohemian waxwing
Bohemian Waxwing Profile: Facts, Traits, Call, Range, Diet
While Bohemian waxwings share some similarities with cedar and Japanese waxwings, they can be easily distinguished from them based on differences in size and plumage. Bohemian waxwings are typically larger and display unique markings that set them apart from their counterparts.
Historical Significance
In the past, the arrival of waxwings was sometimes associated with outbreaks of cholera or plague, leading to the old Dutch and Flemish name “Pestvogel,” meaning “plague bird.” Juniper berries, which they frequently consumed, were believed to offer protection, prompting people to consume the fruit and burn branches to fumigate their homes.
Physical Appearance
Bohemian waxwings are easily recognizable by their appearance. Their overall plumage is a soft, buff-grey color, which provides them with excellent camouflage in their forest habitat. However, what sets them apart are their bold black face markings, which contrast sharply against their light-colored bodies. These markings extend from their eyes to their beaks, adding to their distinctive look. Another prominent feature is their pointed crest, which adorns the top of their heads and further enhances their unique appearance.
Wing Patterns and Coloration
The wings of Bohemian waxwings are adorned with intricate patterns that catch the eye. Among these patterns are patches of brilliant white and vibrant yellow, creating a striking contrast against the bird’s neutral plumage. These colors serve both functional and aesthetic purposes, aiding in camouflage and communication within their social groups. Additionally, some of the wing feathers exhibit a fascinating pink-waxy appearance, which adds an element of intrigue to their overall appearance and behavior.
Distribution and Habitat
Bohemian waxwings are primarily found in the northern regions of the world, where they inhabit dense forests and woodland areas. In the Palearctic region, they are commonly found across Europe and Asia, while in North America, they can be spotted in the boreal forests of Canada and Alaska. These birds are known for their nomadic behavior, often traveling long distances in search of food and suitable breeding grounds. During the winter months, they may venture further south, occasionally appearing in more temperate regions.
Behavior and Ecology
Bohemian waxwings are highly social birds that form tight-knit flocks, especially during the non-breeding season. They are adept fliers and can often be seen performing graceful aerial maneuvers as they forage for food. Their diet primarily consists of berries and insects, and they play an essential role in dispersing seeds within their habitat. Despite their small size, Bohemian waxwings are resilient birds, capable of thriving in the harsh conditions of their northern environment.
Distribution and Habitat
The Bohemian waxwing boasts a widespread distribution, with its range encompassing the circumpolar regions of both Eurasia and North America. In Eurasia, these waxwings establish their breeding grounds just shy of the treeline, typically reaching as far south as approximately the 10°C July isotherm and breeding regionally until about 51°N latitude. The majority of breeding occurs within the latitude range of 60–67°N, extending up to 70°N in Scandinavia. In North America, the subspecies inhabits the northwestern and north-central regions, with its range extending southward beyond the US border into the Rocky Mountains.
Migration Patterns
The Bohemian waxwing is a migratory species, with the bulk of its breeding range abandoned as the birds embark on their southward migration for the winter. Migration commences in September, with an earlier onset in the northern parts of the range and a slight delay in the southern regions. Eurasian populations typically winter across various regions, including eastern Britain, northern parts of western and central Europe, Ukraine, Kazakhstan, northern China, and Japan.
North American breeders follow a southeasterly migration pattern, with many individuals wintering in southeastern Canada and smaller numbers found in the north-central and northeastern US states. Interestingly, individual birds rarely return to the same wintering sites in consecutive years, demonstrating remarkable migratory flexibility.
Irruptions and Seasonal Movements
In certain years, the Bohemian waxwing undergoes irruptions, venturing south of its typical wintering areas in significant numbers. These irruptions are often triggered by variations in fruit abundance, with poor crop years—especially following bountiful seasons—prompting the flocks to migrate farther south in search of adequate food supplies. The waxwings’ reliance on fruit for sustenance makes them susceptible to fluctuations in food availability, leading to dynamic seasonal movements and migrations across their vast range.
Subspecies and Sexual Dimorphism
Bohemian waxwings are relatively uniform in appearance across their three subspecies, with only minor variations distinguishing them. Both males and females share similar plumage characteristics, although young birds tend to be less distinctly marked and may lack the pink waxy wingtips that are characteristic of adults.
Breeding Habitat and Nesting Behavior
During the breeding season, Bohemian waxwings inhabit coniferous forests, often located near bodies of water. Here, they construct their nests, which are cup-shaped and lined with materials such as twigs, moss, and feathers. These nests are usually positioned in trees or bushes, with a preference for locations near the trunk where they are well-protected.
Habitat Preferences
Bohemian waxwings exhibit a remarkable adaptability to various habitats, typically staying until food resources become scarce before moving on to new areas. During what is considered one of the most significant irruptions in Europe, observed during the winter of 2004–2005, Germany alone recorded more than half a million waxwings—an unprecedented event. This mass invasion occurred following an unusually warm and dry breeding season, highlighting the species’ capacity to respond to environmental changes.
Breeding Habitat
The breeding habitat of Bohemian waxwings predominantly consists of mature coniferous forests, with spruce being a favored tree species, although other conifers and broadleaf trees may also be present. Additionally, they utilize more open and moist areas such as lakes and peat swamps, especially for foraging on insects. These wetland environments often feature dead and drowned trees, which provide ample food sources for the waxwings.
Geographic Distribution
Across Eurasia, Bohemian waxwings occupy a diverse range of landscapes, including lowlands, valleys, and uplands. While they typically avoid mountainous regions, they are known to nest in various elevations in North America. The North American subspecies, in particular, can be found nesting in Canada at altitudes ranging from 900 to 1,550 meters (2,950 to 5,090 feet). This adaptability to different elevations underscores the waxwings’ ability to thrive in a variety of habitats across their extensive range.
Reproduction and Parental Care
After the female lays a clutch of three to seven eggs, she assumes the responsibility of incubating them alone for a period of 13 to 14 days until they hatch. Once the chicks emerge from their eggs, they are altricial, meaning they are born in a relatively undeveloped state and require extensive care from both parents. Initially, the parents primarily feed the chicks a diet consisting mainly of insects, which provide essential nutrients for their growth and development.
As the chicks mature, their diet gradually shifts to include more fruit, reflecting the dietary preferences of the adult birds. Throughout this process, both parents play active roles in feeding and caring for their offspring, ensuring their survival until they are ready to fledge and leave the nest.
Physical Characteristics
The Bohemian waxwing is a moderately sized bird, measuring between 19 to 23 centimeters (7.5 to 9.1 inches) in length, with a wingspan spanning from 32 to 35.5 centimeters (12.6 to 14.0 inches). Typically weighing around 55 grams (1.9 ounces), it possesses a short tail and a distinctive crest atop its head.
Bohemian waxwings exhibit distinct physical characteristics. Their eyes are dark brown, complementing their mainly black bill and dark gray or black legs. During flight, their large flocks, long wings, and short tails may resemble the common starling, and their flight is equally swift and direct.
Locomotion
These birds are adept climbers, easily navigating through trees and bushes. However, their movement on the ground is more limited, as they typically shuffle rather than walk.
Feather Maintenance
Bohemian waxwings maintain their soft and dense feathers through preening. This grooming behavior ensures that their feathers remain in optimal condition, providing insulation and aiding in flight.
Unique Feature
One of the most distinctive features of Bohemian waxwings is the presence of pink waxy tips on some of their feathers. These tips are the elongated and flattened ends of feather shafts, pigmented with astaxanthin, a carotenoid pigment found in their diet. These waxy tips are enclosed in a transparent sheath, giving the feathers their characteristic appearance.
Plumage and Coloration
Its plumage is primarily brownish-grey, accentuated by a striking black mask extending through the eye area and a corresponding black throat in males of the species. A prominent white streak is present behind the bill, complemented by a curved white patch beneath the eye. Notably, the lower abdomen boasts a rich chestnut hue, while cinnamon-colored areas adorn the facial mask. The rump exhibits a contrasting gray coloration, while the tail terminates in a vivid yellow band, bordered above by a broad black stripe.
Unique Wing Features
The Bohemian waxwing’s wings are particularly noteworthy, characterized by black flight feathers and primaries featuring distinctive markings. These markings create a striking yellow stripe and white “fishhooks” pattern when the wings are closed. Of special interest are the long red appendages at the end of the secondaries, resembling sealing wax, from which the bird derives its English name.
Sexual Dimorphism
While both males and females share similar plumage patterns, males typically display more pronounced black markings on the face and throat. Additionally, juveniles and young birds may exhibit less well-defined markings and fewer or no waxy wingtips compared to adults.
Adaptations and Behavior
These distinctive physical features and plumage adaptations serve various functions, including communication, species recognition, and courtship displays. Understanding these characteristics provides valuable insights into the Bohemian waxwing’s behavior and ecology, highlighting its remarkable adaptations for survival in diverse habitats across its range.
Species Comparison
The Bohemian waxwing’s characteristics overlap those of other members within the genus Bombycilla.
Cedar Waxwing Comparison
Compared to the Bohemian waxwing, the cedar waxwing is smaller in size with browner upper parts. It features a distinctive white undertail and a white line above the black eye patch. Adult cedar waxwings typically have a yellowish stomach, and their wings are less strongly patterned compared to Bohemian waxwings.
Japanese Waxwing Comparison
The Japanese waxwing stands out from its relatives with several distinct features. It possesses a pink terminal band on the tail, and the black mask extends up the rear of the crest. Additionally, Japanese waxwings lack the yellow stripe and pink tips on the wings observed in Bohemian waxwings.
Vocalizations
The Bohemian waxwing’s vocal repertoire includes a distinctive trill, characterized by a long and low-pitched sound, notably different from its relatives, the cedar waxwing and the Japanese waxwing. This trill is less wavering and lower-pitched than that of the cedar waxwing, and longer and lower-pitched compared to the call of the Japanese waxwing.
Call Variations
In addition to its primary trill, the Bohemian waxwing produces other vocalizations that serve various purposes. These include quieter variants of the main vocalization, often used by chicks to call their parents. During courtship and nest building, the waxwing emits calls with a significantly wider frequency range, adding complexity to their communication.
Flight Sound
When a flock of Bohemian waxwings takes off or lands, their wings create a distinct rattling sound that can be heard from a considerable distance of up to 30 meters (98 feet) away. This auditory cue is a unique feature of their flight behavior and contributes to their overall communication within the flock.
Seasonal Habitat Use
During the non-breeding season, Bohemian waxwings exhibit a flexible habitat selection, occupying various environments as long as suitable fruit sources, such as rowan berries, are available. They can be commonly found along roadsides, in parks, gardens, and along hedges or woodland edges. At this time, they display minimal fear of humans, often foraging near human settlements without disturbance.
Roosting Behavior
In winter, Bohemian waxwings gather to roost communally in dense bushes or hedges, sometimes alongside other wintering species like American robins or fieldfares. This communal roosting behavior provides them with warmth, protection, and social interaction during the colder months.
Breeding Season
Bohemian waxwings typically begin their migration back to breeding areas from their wintering grounds in February or March. However, individuals breeding in northern regions may not reach their breeding sites until April or early May. The breeding season for this monogamous species primarily occurs from mid-June to July, during which time they establish nests and raise their offspring.
Nesting Behavior
Bohemian waxwings are not highly territorial birds, and although they typically breed solitarily, multiple pairs may nest nearby, especially in areas with abundant nesting sites. Males may engage in territorial defense by deterring rival males from approaching their mates, while females may engage in squabbles over nest sites. Aggression is displayed through physical cues such as sleeking down feathers and crests, displaying the black throat, and opening the bill as a warning signal.
Breeding Displays
During the breeding season, male Bohemian waxwings engage in elaborate courtship displays to attract females. Contrary to their defensive behavior, males adopt a posture of elevation, erecting their body and crest feathers while turning their heads away from the female. Additionally, they may repeatedly offer small items, typically food, to their potential mates, presenting it delicately in their open bill. Interestingly, despite these displays, approximately 90% of such interactions do not lead to copulation. Older males, characterized by more prominent pink tips to their wings, are often preferred by females during mate selection.
Nest Construction
The construction of the nest is a collaborative effort between both male and female waxwings. It is typically a cup-shaped structure made of thin twigs and lined with softer materials such as fine grass, moss, fur, or lichen. Positioned at a height ranging from 1.3 to 15 meters (4 to 50 feet) above the ground, the nest is commonly built in pine trees or scrub areas, often near the trunk.
Eggs and Clutch
Bohemian waxwings lay eggs with a striking appearance—a shiny pale blue base adorned with black and gray spots. The typical clutch size ranges from 3 to 7 eggs, although clutches of 5 or 6 eggs are most common. Each egg measures approximately 24 mm × 18 mm (0.94 in × 0.71 in) and weighs about 3.8 g (0.13 oz), with the shell accounting for around 5% of the total weight.
Incubation and Chick Rearing
After the female Bohemian waxwing lays her clutch of eggs, she takes on the sole responsibility of incubating them for a period of 13 to 14 days. During this time, she remains dedicated to her task, rarely leaving the nest and relying on her mate to bring her regurgitated berries for sustenance. Once the eggs hatch, the chicks emerge as altricial and bare, with vibrant pink mouths signaling their readiness for feeding. Both parents take part in feeding the chicks, with the male primarily bringing insects during the initial days, gradually shifting to a diet primarily consisting of fruit as the chicks grow. After approximately 14 to 16 days, the chicks fledge, marking the beginning of their independence from the nest.
Breeding Densities and Lifespan
Breeding densities of Bohemian waxwings are typically modest compared to other passerines, with concentrations usually ranging below ten birds per square kilometer (26 per square mile), even in favorable habitats. However, in some instances, densities as high as 35.6 birds per square kilometer (92 per square mile) have been observed in Russia. These birds typically produce one brood per year, and while the recorded age of individuals varies, the maximum recorded age stands at 5 years and 10 months in North America and over 13 years and 6 months in Europe. Despite their potential longevity, the average life expectancy of Bohemian waxwings remains unknown.
Causes of Mortality
Various factors contribute to the mortality of Bohemian waxwings. Predation by natural predators, collisions with windows and vehicles, and poisoning from ingesting road salt while feeding are among the significant causes of death observed in these birds. Despite these threats, Bohemian waxwings continue to thrive in their habitats, adapting to challenges to ensure the survival of their species.
Plumage Development
Research on cedar waxwings has revealed that the pink waxy tips on feathers are minimal or absent until the bird reaches its third year of life. This characteristic likely applies to Bohemian waxwings as well.
Annual Molt
All adult Bohemian waxwings undergo a complete molt annually, typically between August and January. Juveniles also molt during this period but retain their flight and other wing feathers.
Sexual Dimorphism
While male and female Bohemian waxwings share similar appearances, there are subtle differences. Females typically have a narrower yellow terminal band on the tail, a less defined lower edge to the black throat, and slightly less distinctive wing markings compared to males.
Juvenile Characteristics
Juvenile Bohemian waxwings appear duller than adults, with whiter underparts, few or no pink wing tips, no black on the throat, and a smaller black face mask. These differences help distinguish them from mature individuals.
Subspecies Variation
The subspecies of Bohemian waxwings exhibit variations in appearance. The eastern subspecies, B. g. centralasiae, tends to be paler and greyer with a little reddish-brown behind the bill. The American subspecies, B. g. pallidiceps, has more coloring on the cheeks and forehead but is generally duller overall compared to the nominate form.
Feeding Behavior
Bohemian waxwings are primarily frugivores, meaning they primarily consume fruits, but they also include insects in their diet during the breeding season. While mosquitoes and midges are the most common insect prey, they also feed on a variety of other insects and occasionally spiders. How AI, ChatGPT maximizes earnings of many people in minutes
Foraging Techniques
When hunting insects, waxwings typically catch them by flycatching from an exposed perch, but they may also pluck them off vegetation. When it comes to fruits, they usually pick them directly from trees, sometimes even from the ground, and swallow them whole.
Dietary Preferences
During the summer breeding season, Bohemian waxwings favor fruits from Vaccinium and Rubus species, as well as Canada buffaloberry. Outside the breeding season, their diet shifts to include cotoneaster, juniper, haws, rose hips, and apples. Rowan berries are particularly cherished and eagerly consumed whenever available.
Consumption Rate
Bohemian waxwings have voracious appetites and can consume large quantities of berries, often exceeding their body weight. Remarkably, there have been recorded instances of an individual waxwing consuming between 600 and 1,000 cotoneaster berries in just six hours, with a defecation rate of every four minutes. Motivation – Mind – Success – Thinking – Productivity – Happiness
Role in Seed Dispersal
As they feed, waxwings travel considerable distances in large flocks, which facilitates the dispersal of fruit seeds. These flocks, sometimes comprising several hundred birds, can overwhelm other fruit-eating birds like mistle thrushes, allowing waxwings to monopolize fruit trees.
Metabolic Adaptations
Bohemian waxwings possess a large liver that aids in converting sugar from fruits into energy. They have the remarkable ability to metabolize ethanol produced from the fermentation of fruits, although excessive consumption can lead to intoxication, sometimes fatally.
Drinking Habits
During winter, waxwings often drink water or consume snow to counteract the dehydrating effects of their fruit-heavy diet, which tends to draw water from their bodies through osmosis. However, in the juicier summer months, water is less of a concern. Business – Money Making – Marketing – E-commerce
Predators and Threats
Bohemian waxwings face predation from various birds of prey, including rough-legged buzzards, Eurasian sparrowhawks, prairie falcons, and great gray shrikes. Merlins are also known to attack winter flocks, particularly those in urban areas. When threatened, waxwings exhibit a defensive behavior where they freeze momentarily with their bills and necks pointing upwards before taking flight while emitting noisy calls.
Brood Parasitism
Unlike some bird species, Bohemian waxwings are not susceptible to brood parasitism by common cuckoos or related species in Eurasia. This is because the young cuckoos cannot survive solely on the fruit-based diet typically consumed by waxwings. In North America, where their breeding range minimally overlaps with that of the brown-headed cowbird, another brood parasitic species, any foreign eggs placed in a waxwing’s nest are promptly rejected. This behavior suggests that Bohemian waxwings may have evolved from ancestors that were once hosts to brood parasitic species, retaining the instinct to reject foreign eggs acquired over millions of years. Health books, guides, exercises, habits, Diets, and more
Parasites and Diseases
Bohemian waxwings are susceptible to various parasites and diseases, including parasitic mites such as Syringophiloidus Bombycilla, first identified in this species, and the nasal mite Ptilonyssus Bombycilla. Blood parasites like Trypanosoma species and a Leucocytozoon unique to Bohemian waxwings have also been documented. While these birds may harbor flatworms and tapeworms, cases of parasitic worm infestations are generally low. Regular monitoring and management strategies are essential to mitigate the impact of parasites and diseases on Bohemian waxwing populations.
Fledging and Migration
Bohemian waxwing chicks typically fledge from the nest approximately 14 to 16 days after hatching. Following this stage, many birds vacate their nesting areas during winter and embark on migrations to more southerly regions. In certain years, there are notable irruptions, during which large numbers of Bohemian waxwings venture well beyond their usual winter range in search of fruit, which constitutes a significant portion of their diet. Fitness – Meditation – Diet – Weight Loss – Healthy Living – Yoga
Winter Behavior and Foraging Habits
During winter, Bohemian waxwings can exhibit remarkably tame behavior, often venturing into urban areas and gardens in search of food sources. Among their favored foods are rowan berries, which they eagerly consume. Despite their tolerance for fermented fruit, which they can metabolize to some extent, waxwings may still succumb to intoxication, sometimes with fatal consequences.
Hazards and Threats
Bohemian waxwings face various hazards in their environment, including predation by birds of prey, infestation by parasites, and collisions with vehicles or windows. These factors can pose significant risks to their populations and overall survival. RPM 3.0 – 60% CONVERSION & Money for Affiliate Marketing
Status and Population
The Bohemian waxwing boasts a global population exceeding three million individuals, with its breeding range spanning approximately 12.8 million square kilometers (4.9 million square miles). Despite some indications of a population decline observed as of 2013, the decrease has been gradual and not significant enough to meet conservation vulnerability criteria.
Conservation Assessment
Given its substantial population size and expansive breeding range, the Bohemian waxwing is currently classified as a species of least concern by the International Union for Conservation of Nature (IUCN). This designation reflects the species’ overall robustness and relative stability, indicating that it does not face immediate threats to its survival. Bird accessories on Amazon
Conservation Status
Despite these challenges, the Bohemian waxwing’s robust population numbers and extensive breeding range have led to its classification as a species of least concern by the International Union for Conservation of Nature. While threats exist, the species’ ability to adapt to diverse habitats and its wide distribution contribute to its overall resilience and stability. Continued monitoring and conservation efforts remain important to ensure the long-term viability of Bohemian waxwing populations.
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