Copyright 2001 Cornell Laboratory of Ornithology

Branded as agricultural pests and killers of baby birds, crows have often been persecuted by humans. Despite our attempts to exterminate crows by shooting them and bombing their roosts, crows are as common as ever, a tribute to their intelligence and adaptability.

Studies show that crows are opportunistic omnivores, using a variety of food sources. In areas where they nest near waterfowl, crows can cause great damage to other species' eggs and nestlings. 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 solitarily, 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 tree. The large stick nests can measure two feet across. In areas that lack tall trees, nests may be placed lower in hedgerows or shrubbery. The female incubates the eggs for about 18 days. At times she may be fed by her mate or perhaps by one-year-old birds that remain with their parents as helpers. Only the area immediately around the nest is defended. Crows become very quiet and secretive during the nest-building and incubation period but after the young have hatched, the parents defend them loudly. Parents feed their nestlings primarily insects, especially grasshoppers.

American Crows are found throughout North America from coast to coast. They use a variety of habitats, especially agricultural lands. They avoid dense forests and deserts. Along the northwest Pacific Coast the slightly smaller, and possibly conspecific, Northwestern Crow (C. caurinus) replaces them. While most American Crows in the northern parts of the range migrate only a few hundred miles at most, crows from central Canadian provinces may travel as far as 1400 miles to winter in agricultural areas in the mid-western United States.

Description: American Crows are black from beak to toe. Adults have a light violet-blue gloss on the body and a greenish-blue gloss on the wings. The eyes are dark brown. Nasal bristles cover the basal third of the upper mandible. Sexes are similar. Juveniles have duller plumage than adults. Their blue-gray eyes turn brown as they mature.

American Crows are best distinguished from the smaller Fish Crow (C. ossifragus) by the latter's more nasal voice. The Fish Crow has glossier plumage, thinner bill and relatively longer legs. The Northern Raven (C. corax) is a much larger bird with more prominent bill and head, and a spade-shaped tail. Chihuahuan Ravens (C. cryptoleucus) are close to the crow in body size and intermediate between the Northern Raven and American Crow in bill size. They have longer wings and tail, and a different voice from either Northern Raven or American Crow. They inhabit deserts and arid grasslands, replacing the American Crow in these habitats.

Recording credits:
American Crow recorded by G. B. Reynard. Longer version included on Peterson Field Guide to Eastern/Central Bird Songs.

American Crow in flight