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American Crow by Dawit Eshete The American Crow, known scientifically as Corvus brachyrhynchos, is member of the family Corvidae. The American Crow is classified as being a member of the phylum Chordata, the class Aves (Birds) and the order of Passseriformes. The Crow is a large, chunky, ebony bird completely black from beak to toe. Adults have a light violet-blue gloss on the body and a greenish-blue gloss on the wing. Their eyes are dark brown and they have a loud char sound which can be easily imitated. The American Crow is distinguished by its deep, steady wing beat which often makes the bird look as if it were rowing through the air. The crow is widely distributed over a great part of the North American continent. They use a variety of habitats especially agricultural lands. They avoid dense forests and deserts. American Crows in the northern parts of the range migrate only a few hundred miles at most, crows from central Canadian province may travel as far as 1400 miles to winter in agricultural areas in the mid-western United States. Throughout Virginia, the American Crow is instantly recognized by anyone who sees it, because of its striking coal-black plumage, its large size, its unusual adaptability, its extreme cunning, apparent intelligence and its habit of frequently appearing in the open. The American Crow is labeled as an agricultural pest and a killer of baby birds. Crows have often been persecuted by humans for a long time. Despite our attempts to exterminate crows by shooting them and killing them, crows are as common as ever, a tribute to their intelligence and adaptability. The American Crow is an opportunistic omnivore, using a variety of food sources. In areas where nest are near waterfowl, crows can cause great damage to the eggs and nestlings of other species. However, nestlings and eggs make up only a small portion of the crow’s yearly diet, less than one-third of one percent. The majority of the diet is vegetable. When available, corn may make up more than half of the vegetable diet. Crows can cause damage to corn crops by opening the cobs, exposing them to weather damage. They also consume stored crops and sprouted seeds. In areas without corn, crows may eat wheat or other grains. About 28 percent of their diet consists of animal food, primarily insects (especially beetles and grubs, grasshoppers, locusts and crickets) as well as spiders, millipedes, crustaceans, snails, salamanders, lizards, small mammals, and carrion. Crows are often observed following the plow to feast on exposed earthworms and grubs. As spring approaches, crows are usually found solitary, in pairs, or in small family groups. The male’s dry rattling call uttered in the spring is apparently related to courtship. Males may also engage in diving flight displays, chasing females. Crows seem to prefer to nest in conifers when available. The pair builds a nest from 20 to 60 feet above the ground, usually near the top of the trees. Written spring 2004, as a service learning project for Dr. Gary Coté's Biology 102 class at Radford University. Copyright Pathways for Radford. |
