American Crows and Common Ravens are widely seen all over the Southwest. Both species are in the same genus, Corvus, and both are obsidian-black in color. That can make it tough to tell them apart where their ranges overlap.
But close observation of a few traits can help separate them. One is by sound: crows caw, ravens have a deep croak and a high gurgle.
Size and other physical traits are revealing too. Ravens are generally larger, twice as heavy and with a wingspan at least a foot longer than crows. Their tails are also different --ravens are diamond-shaped, while crows have a rounder fan-shaped tail. The raven’s bill, or beak, is heftier too. In the ornithology world, the raven is said to be “a bill with a bird, while the crow is a bird with a bill.”
Behavior can at times be a distinguishing characteristic: crows tend to be social and stay in flocks, while ravens are often alone or in pairs. Crows will gang up on a single raven, possibly in revenge for a raven’s raiding of a nest to eat the eggs or young of crows. Ravens are also widely admired for their craftiness and aerobatic performances
But behavior isn’t always a sure bet. During summertime at the Grand Canyon, ravens form large flocks on the rims and in meadows on the Kaibab Plateau. And in winter hundreds have been known to congregate on the South Rim in communal roosts.
So, despite their physical similarities, there are many subtle differences between these lookalike birds.