Birds

Corvids: The American Crow

The American crow (Corvus brachyrhynchos) is a medium to large passerine, commonly confused with the common raven (Corvus corax). The confusion occurs because both birds are a deep inky black and some American crows can grow to be quite big, but ravens are BIGGER.

Crow or Raven?

Three ways to tell these two species apart (of many) are tail shape, primary feathers, and throat feathers.

1.) The silhouette of an American crow in flight reveals a straight rounded arrangement of tail feathers. The silhouette of a common raven shows a more wedged looking arrangement, more in the shape of a diamond — wide in the middle and then tapered off at the end (compare the image below with the featured image above);

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Common Raven in Flight. Image Credit: Copetersen / WikiCommons

2.) In flight, the primaries of the common raven branch out like long fingers spread apart, this is less exaggerated in the American crow;

3.) Underneath the bill of an American crow, the throat feathers are neatly tucked-in close to the neck, but in a common raven there is a noticeable shag of what look like ruffled feathers, loose and off the throat.

Family

The American crow is a corvid, part of the family Corvidae under the genus Corvus. Corvidae include ravens, magpies, jay, and others (Taylor 2014). Under the genus Corvus there are approximately 40 species.

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Stellar’s jay (Cyanocitta stelleri). Image Credit: PIXABAY

“Family” and “genus” refer to taxonomic ranks. Taxonomic ranks are how scientists categorize organisms/species. In this example both jays and crows are in the same family, Corvidae, but jays are categorized in the genus Cyanocitta and crows are categorized in the genus Corvus.

Cooperation

The American crow is an omnivore, meaning that it eats a wide variety of foods including other birds, road-kill, seeds, fruit, and even trash (Armistead, Small, 2016). American crows work together to ward off predators by using a series of calls to alert other crows.

In the YouTube video below, a flock of American crows are calling out to warn others about the presence of two red-shouldered hawks (Buteo lineatus) and a red-tailed hawk (Buteo jamaicensis). The event was preceded by the crows mobbing (attacking together) the two red-shouldered hawks (the red-tailed hawk joined in after the even began).

American crows nest in tall trees. Both parents help to build the large nest from materials like twigs, roots, hair, and sticks. The female crow lays a clutch size of between 3-8 eggs. A clutch is a group of eggs that are laid in one nesting period. American crows can lay 1 or 2 clutches per breeding season (Peterson Field Guide).

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Crow’s Nest. Image Credit: PIXABAY

If you have ever heard the term, “crow’s nest” as part of ship terminology, there’s good reason. Crows tend to build their nests very high up in tall trees. The “crow’s nest” on a ship, is a lookout on the highest mast of a ship.

Stay tuned for more information about Corvids!

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