Vocalizations
Blue Jays can make a large variety of sounds, and individuals may vary perceptibly in their calling style. Like other corvids, they may learn to mimic human speech. Blue Jays can also copy the cries of local hawks so well that it is sometimes difficult to tell which it is. Their voice is typical of most jays in being varied, but the most commonly recognized sound is the alarm call, which is a loud, almost gull-like scream. There is also a high-pitched jayer-jayer call that increases in speed as the bird becomes more agitated.This particular call can be easily confused with the chickadee's song because of the slow starting chick-ah-dee-ee. Blue Jays will use these calls to band together to mob potential predators such as hawks and drive them away from the jays' nests.
Blue Jays also have quiet, almost subliminal calls which they use among themselves in proximity. One of the most distinctive calls of this type is often referred to as the "rusty pump" owing to its squeaky resemblance to the sound of an old hand-operated water pump. The Blue Jay (and other corvids) are distinct from all other songbirds for using their call as a birdsong.
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