They look a lot alike, but there are subtle differences...

進入有聲：http://birdnote.org/show/ravens-and-crows-who-who

Is that big black bird a crow or a raven? How can you tell? Ravens (seen right here) often travel in pairs, while crows (left) are seen in larger groups. Also, study the tail as the bird flies overhead. A crow's tail is shaped like a fan, while the raven's tail appears wedge-shaped. Another clue is to listen closely to the birds' calls. Crows give a cawing sound, but ravens produce a lower croaking sound. To learn more about crows and ravens, you can visit All About Birds. Or, get information when you take a class from your local Audubon society.

Microsoft® Translator

一隻烏鴉或烏鴉是那大黑鳥嗎？你怎麼知道？（這裡看到） 的烏鴉經常旅行成對，雖然烏鴉 （左） 都用較大的組。另外，研究尾鳥飛開銷。烏鴉的尾巴的形狀像一個風扇，雖然烏鴉的尾巴出現楔形。另一個線索是密切聽鳥的叫聲。烏鴉給咩咩的聲音，但烏鴉產生低嘶啞的聲音。若要瞭解更多有關烏鴉和烏鴉，您可以訪問所有關于鳥類。或者，獲取資訊，當您從您當地的奧杜邦協會採取一類。