The Nature Writers of Texas

The best nature writing from the newspaper, magazine, blog and book authors of the Lone Star State . . .

Thursday, December 04, 2008

American Crows Are Commonplace, But Often are Ignored
by Ro Wauer

Almost everyone can recognize the American crow! Yet it is too often misidentified throughout much of its Texas range. The crow-like birds in South Texas and in far West Texas and the Panhandle are not our familiar American crow, but actually are Chihuahuan ravens. And the larger crow-like birds of the Hill Country and West Texas is the common raven. The American crow is actually a bird of the eastern, northern and western United States; its range skips much of the western two-thirds of Texas. Like the range of several other eastern North American songbirds, such as the tufted titmouse, Carolina wren, and blue jay, it barely extends south of the San Antonio River.

Crows are members of the Family Corvidae that also includes all the jays, magpies and Clark’s nutcracker. Corvids are some of the most intelligent of all birds, and young birds can often be tamed as pets. They also are able to solve problems and to recognize dangers that many other birds ignore. For instance, crows are reported to warn other crows of a human intruder that is carrying a shotgun. And as for problem solving, Kent Rylander wrote in “The Behavior of Texas Birds,” that crows can add or subtract: “They readily learn how to deal with novel situations (for example, taking advantage of an unconventional food source); and they respond to subtle environmental stimuli to which less intelligent birds are oblivious (for example, distinguishing an aggressive from a nonaggressive gait in a predator.”

American crows are naturally gregarious and usually will be found in flocks. Some wintertime flocks can number in the hundreds of thousands. These cooperative groups often maintain shared territories year-round. They may even fly considerable distances, like 50 miles or more, to feed. And when a predator is located, crows are well known for their mobbing behavior, including constant calling and diving at the intruder. Their best known call is an emphatic “caw caw caw,” but ornithologists have recorded at least 23 different calls. It depends on their situation, for instance, courting males sing a “rattle” song.

Crows are omnivorous and extremely opportunistic. They can take advantage of almost any opportunity to feed, utilizing seeds, grains, insects and other invertebrates, frogs, small snakes, birds and their eggs, small mammals, carrion, and even garbage. There are several instances of crows cracking hard-shelled mollusks by dropping them onto rocks from high overhead.

Like all the Corvids, crows are extremely wary and suspicious. Resting or feeding groups post sentinel birds to warn the group of any dangers. Sneaking up on a flock of crows takes special skills that few humans possess. However, by approaching ground-feeding crows indirectly and by looking away can produce some success. But just when you stop to aim a camera they will take off in the opposite direction with much consternation and vocalizations.

Although our American crow is so often taken for granted, probably because of their abundance and continual presence in the Golden Crescent, it is one of our most interesting songbirds. It is one of the first birds to call each morning, and one of the last to go to roost in the evening. It is one of our largest songbirds, yet its song is little more than a series of caw notes.

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