Blue Jay

Detail about Blue Jay:

The Blue jay (Cyanocitta cristata) is a passerine bird in the family Corvidae, native to North America. It resides through most of eastern and central United States, although western populations may be migratory. Resident populations are also found in Newfoundland, Canada, while breeding populations can be found across southern Canada. It breeds in both deciduous and Coniferous forest, and is common in residential areas. It 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, and plumage does not vary throughout the year. Four subspecies of the blue jay have been recognized.

                                 The blue jay mainly feeds on nuts and seeds such as acorns, soft fruits, arthropods, and occasionally small vertebrates. It typically gleans food from trees, shrubs, and the ground, though it sometimes hawks insects from the air. Like squirrels, blue jays are known to hide nuts for later consumption. It builds an open cup nest in the branches of a tree, which both sexes participate in constructing. The clutch can contain two to seven eggs, which are blueish or light brown with brown spots. Young are altricial, and are brooded by the female for 8–12 days after hatching. They may remain with their parents for one to two months.

                                The name "jay" derives from its noisy, garrulous nature and has been applied to other birds of the same family, which are also mostly gregarious. It is sometimes called a "jaybird".

Description:

The blue jay measures 22–30 cm (9–12 in) from bill to tail and weighs 70–100 g (2.5–3.5 oz), with a wingspan of 34–43 cm (13–17 in). Consistent with Bergmann's rule, jays from Connecticut averaged 92.4 g (3.26 oz) in mass, while jays from warmer southern Florida averaged 73.7 g (2.60 oz). 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.

                                 Its plumage is lavender-blue to mid-blue in the crest, back, wings, and tail, and its 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 all black. Males and females are almost identical, but the male is slightly larger.

                                 As with most 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 because the structure is destroyed. This is referred to as structural coloration.

Distribution and Habitat:

The blue jay occurs from southern Canada (including the southern areas of provinces from Alberta eastward to Quebec and throughout the Atlantic provinces) and throughout the eastern and central United States south to Florida and northeastern Texas. The western edge of the range stops where the arid pine forest and scrub habitat of the closely related Steller's jay (C. stelleri) begins, generally in the eastern foothills of the Rocky Mountains. Recently, the range of the blue jay has extended northwestwards so that it is now a rare but regularly seen winter visitor along the northern US and southern Canadian Pacific Coast. As the two species' ranges now overlap, C. cristata may sometimes hybridize with Steller's jay. 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.

                               The northernmost subspecies C. c. bromia is migratory, subject to necessity. It may withdraw several hundred kilometres 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.

                                The blue jay occupies a variety of habitats within its large range, from the pine woods of Florida to the spruce-fir forests of northern Ontario. It is less abundant in denser forests, preferring mixed woodlands with oaks and beeches. It has expertly adapted to human activity, occurring in parks and residential areas, and can adapt to wholesale deforestation with relative ease if human activity creates other means for the jays to get by.

Reproduction:

The mating season begins in mid-March, peaks in mid-April to May, and extends into July. Any suitable tree or large bush may be used for nesting, though an evergreen is preferred. The nest is preferentially built at a height in the trees of 3 to 10 m (9.8 to 32.8 ft). It is cup-shaped and composed of twigs, small roots, bark strips, moss, other plant material, cloth, paper, and feathers, with occasional mud added to the cup.

                                 Blue jays are not very picky about nesting locations. If no better place is available – e.g. in a heavily deforested area – they will even use places like the large mailboxes typical of the rural United States. They also appropriate nests of other mid-sized songbirds as long as these are placed in suitable spots; American robin nests are commonly used by blue jays, for example.

                                 Blue jays typically form monogamous pair bonds for life. Both sexes build the nest and rear the young, though only the female broods them. The male feeds the female while she is brooding the eggs. There are usually between 3 and 6 (averaging 4 or 5) eggs laid and incubated over 16–18 days. The young fledge usually between 17–21 days after hatching.

                                 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. Sexual maturity is reached after one year of age. Blue jays have been recorded to live for more than 26 years in captivity and one wild jay was found to have been around 16–17, and a half 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.

Diet:

Blue jays have strong black bills which they use for cracking nuts, usually while holding them with their feet, and for eating corn, grains and seeds. 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, fruits 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.

Blue Jay Video:

Blue Jay Basic Information:

Kingdom: Animalia.

Phylum: Chordata.

Class: Aves.

Order: Passeriformes.

Family: Corvidae.

Genus: Cyanocitta.

Species: C. cristata.

Binomial Name: Cyanocitta cristata.

Mass: 65-110 g.

Length: 22-30 cm.