Originally published on www.critters360.com
Crows are nearly universally known, except for in parts of the South Pacific and southern South America. The general behavior and habits of the American crow would be well known to those who observe the jackdaw in Eurasia and North Africa.
While they might be observing different varieties of crows, there are many stories about the crow’s intelligence and cunning on both sides of the Atlantic. From Eurasia, perhaps the best-known stories are from Aesop’s Fables.
Crows are members of the Family Corvidae, which has about 100 species worldwide. The crows in North America include the fish crow, the American Crow, and the white- necked and northern ravens. The large family also includes the blue jay, scrub jay, gray jay, and black-billed magpie.
The American Crow
The Corvus brachyrhynchos is the most widespread and well-known bird in North America. The American crow is about 17-21 inches long with a wingspan of 33 to 40 inches. It is all black, and its distinctive “caw-caw-caw,” with its many variations, is a common sound in city or country.
With intelligence and social behavior, including sentries, crows are difficult to approach. When flying in a flock, they are usually far apart rather than in a tight formation. Crows form large flocks, especially in winter. Up to several thousand birds may fill the entire horizon.
Crows eat nearly anything, from insects to seeds and sprouting plants, eggs and young of birds and reptiles, small mammals, garbage, and carrion They are often seen on the ground in dumps, behind super markets, or at the roadside eating carrion, oblivious to passing traffic. While single birds may be seen in the country, in cities, they are most often seen in groups of 5 to 10 birds, or larger flocks.
Breeding and Nesting
American crows are monogamous and solitary nesters. The nest is made of twigs and branches, lined with grass, feathers, bark, moss, leaves, and hair. This is usually in the fork of a tree, often over 50 feet off the ground.
The 4 to 8 eggs are pale bluish-green to pale olive-green with brown or olive gray splotches. Incubation is about 18 days by both sexes. The altricial young spend about a month in the nest before fledging. There may be two broods in the south.
Crows are an interesting bird to watch for behavior that can sometimes be quite surprising. They will sometimes “mob” a hawk or owl, seen as a threat. Several crows may dive-bomb a hawk from above, forcing it into the tree-tops.
As they often eat eggs and young birds, they are a threat to many smaller birds. Sometimes the crow is on the receiving end of mobbing behavior as a response. This is commonly done by grackles and red-winged blackbirds. As the crow flies through an area, it is harassed and attacked, usually from above and behind. The smaller birds pester the crow unmercifully to drive him out of the neighborhood.
At other times, a crow may actually try to attack small animals imitating a raptor. One day, my wife and I observed a crow chasing a squirrel. It was trying to clutch the frightened animal with its feet, similar to a hawk swooping down on a rabbit or mouse. Its feet are not effectively strong like a raptor’s talons; it was unsuccessful in catching the squirrel. It certainly was comical, though it’s doubtful if the harassed squirrel appreciated the joke.
But the crow is sometimes on the receiving end of this joke as well. Crows will often be in groups with a sentry bird, and one cawing crow may soon lead to a chorus when a threat is near. One April morning near dawn in a park’s woodlands, there was a tremendous outcry of several crows that just would not stop. This small flock of crows was in frenzy, in trees about 20 to 30 feet off the ground. At the base of a tree, there was a crow struggling on the ground, its head and upper torso disappearing down the throat of a red fox.
The fox also out witted the crow in Aesop’s fable of the Fox and the Crow. In that story, the fox flattered the crow into speaking to prove it had a voice matching its beauty. As the crow cawed, it dropped a piece of stolen meat, which was then eaten by the fox.
In the spring morning observation related above, the fox again outwitted the crow. This time it resulted in the crow’s demise amidst the lamenting chorus of its friends and family.
Alsop, Fred J. III. Smithsonian Handbooks: Birds of North America, New York: DK Publishing, 2001.
Gillard, E. Thomas. Living Birds of the World. Doubleday & Company, Garden City, New York: 1967.
Pearson, T. Gilbert, Editor. Birds of America, 1936, Doubleday & Company.
Peterson, Roger Tory. A Field Guide to the Birds, 1980. (Eastern North America)
Aesop’s Fables.com The Fox and the Crow.