A stocky, black bird with a purple or blue iridescence in some lighting, stout bill, and fan-shaped tail. Widespread and very common, crows can be destructive to crops and often carry off and hide bright objects. However, they are very intelligent birds that eat enormous amounts of harmful insects. Usually the birds thrust their heads up and down as they utter their call. American crows can also produce a wide variety of sounds and sometimes mimic noises made by other animals, including other birds, such as barred owls.