Bluejay, passeriforme songbird suborder crow of the family corydalis. The crown is obvious and rises and falls under the influence of their mood. When excited, attacked and courted, the crowns would stand high; when frightened, they would open in all directions like a brush; in courtship and flight, when they showed obedience, they would squat down and shake their feathers to erect the crown. It is mainly distributed in North America and inhabits in mixed forest land and deciduous forest zone.
Bluejay is a noisy and active bird in winter and spring, but it is quiet and secretive during breeding season. In close communication, very quiet calls are also used, which are almost imperceptible to human beings, including click, cluck, hum, Gaga and ring tones. One of the most distinctive of these calls is called "rusty water pump" because it resembles the old manual pump sound.
They will sing softly in spring. Birds of the family Corydalis, including the Bluejay, are unique compared with other songbirds because they can use their calls to create very complex songs. A song may last more than 2 minutes at a time.