Juvenile Blue Jay #5
by J McCombie
Title
Juvenile Blue Jay #5
Artist
J McCombie
Medium
Photograph - Untouched
Description
This piece has been featured in the FAA Group, "A Birding Group - Wings".
The blue jay (Cyanocitta cristata) is a passerine bird in the family Corvidae, native to North America. It is resident through most of eastern and central United States and southern Canada, although western populations may be migratory. It breeds in both deciduous and coniferous forests, and is common near and in residential areas. It is predominantly lavender-blue to mid-blue with a white face and chest and off-white or light grey underparts, and a large perky blue crest. It has a black, U-shaped collar around its neck and a black border behind the crest. It has a broad, rounded tail. The wing primaries and tail are strongly barred with black, sky-blue and white. The bill, legs, and eyes are all black. Sexes are similar in size (the male is slightly larger) and plumage, and plumage does not vary throughout the year. Blue Jays lower their crests when they are feeding peacefully with family and flock members or tending to nestlings. The pigment in Blue Jay feathers is melanin, which is brown. The blue color is caused by scattering light through modified cells on the surface of the feather barbs. As with most other blue-hued birds, the blue jay's colouration 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 colouration. The black bridle across the face, nape, and throat varies extensively and may help Blue Jays recognize one another. Four subspecies of the blue jay are recognized.
Blue Jays are smaller than crows, larger than robins. 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). Jays from Connecticut averaged 92.4 g (3.26 oz) in mass, while jays from 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. Blue Jays are known for their intelligence and complex social systems with tight family bonds.
This common, large songbird is familiar to many people, with its noisy calls. Blue Jays make a large variety of calls that carry long distances. Most calls produced while the jay is perched within a tree. Usually flies across open areas silently, especially during migration. The Blue Jay frequently mimics 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. The bird's name derives from its noisy, garrulous nature. It is sometimes called a "jaybird".
Blue Jays are birds of forest edges. A favorite food is acorns, and they are often found near oaks, in forests, woodlots, towns, cities, parks. Their fondness for acorns is credited with helping spread oak trees after the last glacial period.
Blue Jays glean insects and take nuts and seeds in trees, shrubs, and on the ground; they also eat grains. They also take dead and injured small vertebrates. Blue Jays sometimes raid nests for eggs and nestlings, and sometimes pick up dead or dying adult birds. Stomach contents over the year are about 22 percent insect. Acorns, nuts, fruits, and grains made up almost the entire remainder. Of 530 stomachs examined, traces of bird eggs and nestlings were found in only 6 stomachs, although a search was specially made for every possible trace of bird remains. Blue Jays stuff food items in throat pouch to cache elsewhere to eat later; when eating, they hold a seed or nut in feet and pecks it open.
Nests are an open cup of twigs, grass and sometimes mud, lined with rootlets. Blue Jays build their nests 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 male does more gathering and female more building. Twigs used in outer part of nest are usually taken from live trees, and birds often struggle to break them off. Birds may fly great distances to obtain rootlets from recently dug ditches, fresh graves in cemeteries, and newly fallen trees. 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. Jays may abandon their nest after detecting a nearby predator.
Thousands of Blue Jays migrate in flocks along the Great Lakes and Atlantic coasts, but much about their migration 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. No one has worked out why they migrate when they do. The oldest known wild, banded Blue Jay lived to be at least 17 years 6 months old.
Uploaded
September 30th, 2020
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