Blue Jay

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Blue Jay
Cyanocitta cristata

Male and female are simmilar in appearance with the male being slightly larger. The male Blue Jay measures 9–12" from bill to tail, with a wingspan of 13 to 17" and weighs 2 1/2 to 3 1/2 ounces. There are four subspecies.

Its plumage is lavender-blue to mid-blue in the crest, back, wings, and tail. The face is white. The underside is off-white and the neck is collared with black which extends to the sides of the head. The wing primaries and tail are strongly barred with black, sky-blue and white. The bill, legs, and eyes are black.

There is a pronounced crest on the head, a crown of feathers, which can be raised or lowered. When excited or aggressive, the crest may be fully raised. When frightened, the crest bristles outwards, brushlike. When the bird is feeding among other jays or resting, the crest is flattened to the head. Banded Blue Jays have lived to be 10 to 17 years 6 months the oldest.

As with other blue-hued birds, the Blue Jay's coloration is not derived from pigments but is the result of light interference due to the internal structure of the feathers. If a blue feather is crushed, the blue disappears as the structure is destroyed, the natural color is a brown.

Adults go through a complete change of plumage between June and September. During this molting period Blue Jays may be seen anting, a term referring to a bird using ants or ant excretions for preening. Excited anting birds often trip over their own tail in frantic efforts to apply ants with their bill to the underside of their wings.

The Blue Jay can be recognized from a distance by its apparently effortless flight. It flies with the body and tail held level, with slow, easily discernible wing strokes, which carry it along at 20-25 mi/h.

Blue Jays are found in both deciduous and coniferous forests especially near oak trees; they’re more abundant near forest edges than in deep forest. They’re common in urban and suburban areas, especially where bird feeders are found. The northern jay is migratory, subject to necessity. It may withdraw south in the northernmost parts of its range, but even northern birds do not necessarily move south, particularly in mild years with plentiful winter food.

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. It migrates during the daytime, in loose flocks ranging from 5 to over 200 birds. In 2009 the Jays stayed the winter, in 2010 they left in late Nov. and returned in early Feb. 2011.


Diet

The Blue Jay mainly feeds on nuts, seeds and grains such as acorns, hazelnuts, beechnuts, corn, weed seeds, sunflower seeds, grain, fruits and berries, peanuts, bread, meat and eggs.

It typically gleans food from trees, shrubs, and the ground, though it sometimes hawks insects from the air. Blue Jays have strong black bills used for cracking nuts. They hold the hull of a seed beneath their feet while pecking it open to extract the kernel. They also eat insects such as beetles, grasshoppers, and caterpillars.

Whole peanuts and other shelled food items are sometimes carried off in the beak to be dealt with at leisure. Blue Jays will carry food in their throat and upper esophagus like pouch. They may store 2-3 acorns in the pouch, another one in their mouth, and one more in the tip of the bill. In this way they can carry off 5 acorns at a time to store for later feeding. Six birds with radio transmitters each cached 3,000-5,000 acorns one autumn.

They will conceal feed under leaves, grass, and in hollow trees. In winter, Blue Jays commonly carry away food from a feeding station, especially bread and sunflower seeds, to be hidden in trees and shrubs and later found and eaten. A regular supply of feed will attract Blue Jays to a feeder. Blue Jays prefer feeders on a post rather than hanging feeders. They enjoy peanuts, sunflower seeds, suet, and often take drinks from birdbaths.


Sound

Thornton W. Burgess storybooks tell of the noisy, aggressive, and handsome Sammy Jay, a literary characterization of the Blue Jay, also seen on the television, Tales of the Green Forest. It was Sammy Jay who flew across the Green Meadows and into the Green Forest screaming "Thief! Thief! Thief!" whenever Reddy Fox appeared. In reality, the Blue Jay frequently does play this role, its loud cries warning other birds and mammals of an approaching predator, whether fox or person.

Their most characteristic sound is an unrelenting steel-cold scream, they have a wide variety of other calls, particularly a mellow whistle, quite musical in form, and a continuous sweet warbling heard during courtship.

Blue Jays calls carry long distances. Most calls are produced while the jay is perched in a tree. While they usually fly across open areas silently, especially during migration. The Blue Jay frequently mimic the calls of hawks, especially the Red-shouldered Hawk. These calls may provide information to other jays that a hawk is around, or may be used to deceive other species into believing a hawk is present. Captive Blue Jays sometimes learn to mimic human speech and meowing cats.

Blue Jays mimic a lot of things, and will mimic a hawk when a lot of squirrels and birds are feeding to scare them away so they can get to the feed. That doesn't work in the winter because the hawks migrate! But early in the spring it is funny to watch, because you will hear a screech and think a hawk is there, all of the animals will scatter and in will come a Blue Jay, when I figured out how smart they are I had a good laugh.

The Blue Jay may chase predatory birds, such as hawks and owls, and will scream if it sees a predator within its territory. Smaller birds often recognize this call and hide themselves away accordingly. 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 Jays & crows will mob it until it takes a new roost. They will use loud calls to band together to mob potential predators such as hawks and drive them away from the jays' nest.


Click here for jay calls

Nests & Nesting

Blue Jays build a bulky nest in the crotch or thick outer branches of a deciduous or coniferous tree, usually 10-25 feet above the ground. Male and female both gather materials and build the nest, but on average the male does more gathering and the female more building. They also appropriate nests of other mid-sized birds as long as these are placed in suitable spots such as Robin nests are commonly used by Blue Jays.

The outer part of the nest consists of twigs and a variety of other materials such as bark strips, lichens, moss, grass, cloth, and even paper. The inner part of the nest is cup shapped, with mud, then lined with fine rootlets and feathers. Live twig roots are used on the nest, birds often struggle to break them off, sometimes flying great distances to obtain rootlets from recently dug ditches or newly fallen trees.

Before the final nest is made, the birds build several incomplete nests as part of their courtship ritual. Blue Jays often mate for life and remain together throughout the year. Blue Jay practice courtship feeding. This begins prior to nest building and continues through egg laying and incubation. The incubating female is sometimes fed on the nest, but more often she joins her mate in a nearby tree, assumes the begging posture of a juvenile, and is then fed. Blue Jays will also hop stiff-leggedly from branch to branch during courtship.

During the nesting season, the pair may be quiet and unobtrusive near the nest. Jays may abandon their nest after detecting a nearby predator. Up to seven eggs are laid in a clutch. The eggs are about 1" long and a little over a half inch around. From one clutch to another, the eggs vary in color from buffy to greenish or bluish, spotted and blotched with brown. The female incubates the eggs while the male provides all of her food. Incubation of the eggs lasts from 16 - 18 days.

The young at the time of hatching are entirely naked, eyes closed, the mouth lining is red. They are quite helpless, although on certain signals, particularly the thump of a bird landing on the edge of the nest, they raise their head with mouth open ready to receive food from the parent bird.

The female broods them for 8-12 days during this time the male provides food for his mate and the nestlings. The female shares food gathering after this time, but the male continues to provide more food than female.

Some nestlings begin to wander as far as 15 feet from the nest 1-3 days before the brood fledges. Even when these birds beg loudly, parents may not feed them until they return to the nest; this is the stage at which many people find an abandoned baby jay. If it can be near the nest, the parents will resume feeding it. The brood usually leaves the nest together (fledge) usually when they are 17-21 days old. When young jays leave the nest before then, it may be because of disturbance. The jays are usually farther than 75 feet from the nest by the end of the second day out of the nest. After the juveniles fledge, the family travels and forages together until early fall, when the young birds disperse to avoid competition for food during the winter.

Blue Jays, are highly curious. Young will playfully snatch brightly coloured or reflective objects, such as bottle caps or pieces of aluminium foil, and carry them around until they lose interest.

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