The blue jay (Cyanocitta cristata) is a passerine bird in the family Corvidae, native to eastern North America. It lives in most of the eastern and central United States; some eastern populations may be migratory. Resident populations are also in Newfoundland, Canada; breeding populations are found across southern Canada. It breeds in both deciduous and coniferous forests, and is common in residential areas. Its coloration is predominantly blue, with a white chest and underparts, and a blue crest; it has a black, U-shaped collar around its neck and a black border behind the crest. Males and females are similar in size and plumage, which does not vary throughout the year. Four subspecies have been recognized.

The blue jay feeds mainly on seeds and nuts, such as acorns, which it may hide to eat later; soft fruits; arthropods; and occasionally small vertebrates. It typically gleans food from trees, shrubs, and the ground, and sometimes hawks insects from the air. Blue jays can be very aggressive to other birds; they sometimes raid nests and have even been found to have decapitated other birds.

It builds an open cup nest in the branches of a tree; both sexes participate. The clutch may be two to seven eggs, which are bluish or light brown with darker brown spots. Young are altricial, and are brooded by the female for 8–12 days after hatching. They may stay with their parents for one to two months.

The name jay derives from the bird's noisy, garrulous nature and has been applied to many other birds of the same family, which are also mostly gregarious. Jays are also called jaybirds.

Taxonomy

The blue jay was first described as Pica glandaria cærulea cristata in English naturalist Mark Catesby's 1731 publication of Natural History of Carolina, Florida, and the Bahamas. It was later described as Corvus cristatus in Carl Linnaeus' 1758 edition of Systema Naturae. In the 19th century, the jay was described by French ornithologist Charles Lucien Bonaparte in 1838 as Cyanocorax cristatus in A geographical and comparative list of the birds of Europe and North America, and given its modern scientific name Cyanocitta cristata by Hugh Edwin Strickland in 1845. The genus name Cyanocitta derives from the Greek words kyaneos (blue) and the kitta and kissa (chattering bird, jay), and the term "blue chatterer" refers to the bright blue plumage of the head, nape, back, and tail of the bird. The specific name cristata (crested, tufted) derives from Latin referring to the prominent blue crest of the jay.

Description

thumb|left|upright|[[John James Audubon drawing circa 1830s]]

The blue jay measures from bill to tail and weighs , with a wingspan of . There is a pronounced crest on the head, a crown of feathers, which may be raised or lowered according to the bird's mood. When excited or aggressive, the crest will be fully raised. When frightened, the crest bristles outwards, brushlike. When the bird is feeding among other jays or resting, the crest is flattened on the head. if a blue feather is crushed, the blue disappears because the structure is destroyed. The actual pigment in its feathers is melanin.

The increase in trees throughout the Great Plains during the past century due to fire suppression and tree planting facilitated the western range expansion of the blue jay as well as range expansions of many other species of birds. From 1966 to 2015, the Blue Jay experienced a population decline along the Atlantic coast, but a greater than 1.5% annual population increase throughout the northern part of its range, including Labrador, Nova Scotia, southern Quebec, and southern Manitoba.

The northernmost subspecies C. c. bromia is, subject to necessity, migratory. It may withdraw several hundred kilometers south in the northernmost parts of its range. Thousands of blue jays have been observed to migrate in flocks along the Great Lakes and Atlantic coasts. It migrates during the daytime, in loose flocks of 5 to 250 birds. Much about their migratory behavior remains a mystery. Some are present throughout winter in all parts of their range. Young jays may be more likely to migrate than adults, but many adults also migrate. Some individual jays migrate south one year, stay north the next winter, and then migrate south again the next year. To date, no one has concretely worked out why they migrate when they do. Likely, it is related to weather conditions and how abundant the winter food sources are, which can determine whether other northern birds will move south.

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|140x140px || Cyanocitta cristata cristata|| Coastal blue jay || The nominate subspecies, mid-sized and vivid blue. || Coastal USA from North Carolina to Texas, except southern Florida. Type locality: southeastern South Carolina.

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|140x140px || Cyanocitta cristata semplei

| Florida blue jay || The smallest subspecies, much like C. c. bromia in color. || Southern Florida. Type locality: Coconut Grove, Miami-Dade County, Florida.

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Behavior

thumb|right|[[Merlin (bird)|Merlin chasing a blue jay]]

The blue jay is a noisy, bold, and aggressive passerine. It is a moderately slow flier (roughly ) when unprovoked. It flies with body and tail held level, with slow wing beats.

Its slow flying speeds make this species easy prey for hawks and owls when it flies in open areas. Virtually all the raptorial birds sympatric in distribution with the blue jay may prey upon it, especially swift bird-hunting specialists such as the Accipiter hawks. Diverse predators may prey on jay eggs and young up to their fledgling stage, including tree squirrels, snakes, cats, crows, raccoons, opossums, other jays and possibly many of the same birds of prey who attack adults.

The blue jay can be beneficial to other bird species, as it may chase predatory birds, such as hawks and owls, and will scream if it sees a predator within its territory. It has also been known to sound an alarm call when hawks or other dangers are near, and smaller birds often recognize this call and hide themselves away accordingly. It may occasionally impersonate the calls of raptors, especially those of the red-tailed and red-shouldered hawks, possibly to test whether a hawk is in the vicinity, though also possibly to scare off other birds that may compete for food sources. It may also be aggressive towards humans who come close to its nest, and if an owl roosts near the nest during the daytime the blue jay mobs it until it takes a new roost. Jays are very territorial birds, and they will chase others from a feeder for an easier meal. Additionally, the blue jay may raid other birds' nests, stealing eggs, chicks, and nests. However, this may not be as common as is typically thought, as only 1% of food matter in one study was bird material.

Blue jays, like other corvids, are highly curious and are considered intelligent birds. Young individuals playfully snatch brightly colored or reflective objects, such as bottle caps or pieces of aluminum foil, and carry them around until they lose interest. A wild blue jay was observed using a piece of bark to aid in catching a spider.

Diet

Blue jays are omnivorous, but the Audubon Society estimates that 75% of their diet is vegetable matter. They have strong black bills which they use for cracking nuts, usually while holding them with their feet, and for eating corn, grains and seeds. Blue jays particularly love to eat peanuts in the shell. Its food is sought both on the ground and in trees and includes virtually all known types of plant and animal sources, such as acorns and beech mast, weed seeds, grain, fruit, and other berries, peanuts, bread, meat, small invertebrates of many types, scraps in town parks, bird-table food and rarely eggs and nestlings. Blue jays will sometimes cache food, though to what extent differs widely among individuals. Although seemingly contentious in their general behavior, blue jays are frequently subservient to other medium-sized birds who visit bird feeders. In Florida, blue jays were dominated at feeders by eastern gray squirrels, Florida scrub jays, common grackles, and red-headed woodpeckers, all of which were occasionally observed to aggressively prevent the jays from feeding. Another wild jay was found to have been around years old. A more common lifespan for wild birds that survive to adulthood is around 7 years. Beyond predation and the occasional collision with man-made objects, a common cause of mortality in recent decades has been the West Nile virus, to which corvids as a whole seem especially susceptible. However, despite several major local declines, overall blue jays have not seemed to have been depleted by the disease.

An anthropomorphic blue jay named Mordecai is one of the main characters of the Cartoon Network animated television series Regular Show.

Mascots and symbols

The blue jay is the provincial bird of the province of Prince Edward Island in Canada.

The blue jay is also the official mascot for Johns Hopkins University, Elmhurst University, and Creighton University.

The blue jay was adopted as the team symbol of the Toronto Blue Jays Major League Baseball team, as well as some of their minor league affiliates. Their mascot, Ace, is an anthropomorphic blue jay.

References

  • Blue Jay ID, including sound and video, at Cornell Lab of Ornithology
  • Blue Jay – Cyanocitta cristata – USGS Patuxent Bird Identification InfoCenter archived May 2010
  • Blue Jay at borealforest.org archived May 2021
  • Blue Jay Bird Sound at Florida Museum of Natural History archived January 2011
  • Photo essay of blue jay nestlings archived April 2014