The Common Raven and the American Crow
By Tait Johansson
The
American Crow (Corvus brachyrhynchos) is familiar to everyone. One
of the most common and visible birds in our area, this crow is found in almost
every habitat, including towns, forests, fields, and suburbia. A less familiar
bird to many is the Common Raven (Corvus corax), formerly
extirpated from the area, and now making a comeback, especially in Putnam county
and northern Westchester County. Many birders find it difficult telling crows
and ravens apart, but the two species can be readily distinguished with
experience.
Telling ravens from crows by sight has much in common with
raptor identification. Shape, proportions, and size are the important
characteristics to focus on, since the plumage color of both species is an
identical black (barring the occasional bird of both species with manifestations
of albinism, often just a few white flight feathers).
Compared to the familiar crow, the raven is a considerably
larger bird, approaching almost twice as large in some cases. But since there is
a good deal of size variation between individuals in both species, and because
of the inherent difficulty of judging size at a distance, this character is
really only useful when the bird in question is right next to another bird of
known size. One result of this size (or, in this case, weight) difference is
that, when flushed, a crow standing on the ground tends to fly directly into the
air, while a raven has to take a few hops before it can get its greater bulk
into the air and flying.
A perched raven, compared to a crow, has a longer, heavier
bill, slightly shaggier throat feathers, and a longer, more wedge-shaped tail
than a crow (the end of a crow’s tail is basically straight). But the shape
differences between the two are most apparent in flight, where both the greater
length of the more pointed tail of the raven and its longer, more pointed wings
can be better seen. Combined with the raven’s longer neck and slightly longer
bill, the overall effect is more “stretched out” looking than a crow.
The two species also act differently in flight. Crows are
rather staid: they don’t experiment with their powers of flight much. Ravens
often soar; crows won’t for more than a second or two. Ravens also are often
wackily acrobatic when flying, and when around other ravens will sometimes
perform impressive tumbles and rolls in mid-air which crows would be embarrassed
to even attempt.
The best “field mark” of all, though, is voice. While both are
capable of a wide array of vocalizations, the raven’s typical call is a croaking
“RRRUK”, given singly or in a series, quite different from the American Crow’s
familiar “CAWW.”*
*I hate to complicate things, but there’s another species to
worry about in all this: the Fish Crow (Corvus ossifragus). This
species is, for all practical purposes, identical to the American Crow in
appearance, but gives a nasal “UH-UH” call. This is quite distinctive, but care
should be taken if there are begging juvenile American Crows around, which give
a similar nasal call (usually not two-noted). This species is found throughout
our area, but is less common than the American Crow.
Photo Courtesy of and Copyright © by Rick Paris
rick@rickparis.com
www.rickparis.com
Copyright © 2008 Bedford Audubon Society
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