• © istockphoto.com/Frank Leung

Fast Facts: Blue jay

Scientific name: Cyanocitta cristata
Average weight: 70 to 100 g
Average height: 30 cm in length from the bill to the tail
Average lifespan: 7 years

Did you know?

The Blue Jay’s feathers are not actually blue. The bright cobalt colour is the result of the unique inner structure of the feathers, which distort the reflection of light off the bird, making it look blue.


The Blue Jay is a white-faced bird with a distinctive blue crest, back, wings and tail. A collar of black is often found around the throat and head, and bills, legs, feet and eyes are also black. The Blue Jay has a very heavy bill which is used to peck open a variety of nuts, acorns and cocoons.

Male and female Blue Jays are almost identical in appearance. Males are just slightly larger than females.


The Blue Jay is known as a loud and aggressive bird. Its cries are used to warn other birds and animals of danger, but are also often used for no apparent reason. The jay is also known to imitate hawk calls. Its distinctive crest is used as a communication tool to convey the bird’s mood. When the crest is erected, making a prominent peak, the bird is excited, surprised, or aggressive. If the jay is frightened, the crest bristled out in all directions. If the bird is relaxed, the crest is laid flat on the head.

Adult Blue Jays are known for their unusual moulting behaviour. The birds undergo a complete change of plumage between June and July, and are avid ‘anters’ during this period. ‘Anting’ is the process of using ants or other materials to preen or clean feathers. Birds have been known to use odd materials, including lit cigarettes, to ‘ant.’

The bulk of the jay’s diet consists of fruits, nuts, grains and insects, but it is also known to feed on the eggs and young of other bids.  Blue Jays are monogamous, and form long-lasting bonds. The male and female both help to build the nest and the male remains with the female to feed her throughout courtship and incubation of the eggs.


The Blue Jay has a large range, encompassing a variety of habitats. It prefers mixed wood forests, which provide it with a larger variety of food. It is found from southern Canada to Texas and Florida. It is a partially migratory bird, particularly in the northern parts of its range.

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