Taxonomy
The American Crow was described by Christian Ludwig Brehm in 1822. Its scientific name means literally "short-billed crow", from Ancient Greek brachy- (βραχυ-) "short-" and rhynchos (ρυνχος) "billed".
The Northwestern Crow (C. caurinus) is very closely related to the American Crow. Its ancestors became separated by Ice Age glaciation west of the Rocky Mountains. It is endemic to Pacific temperate rain forests where it all but replaces the American Crow. Only in the Seattle region do they co-occur to any extent. In form the two species are much alike. There is a marked difference in voice.
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