You are outside more now that the weather is warming, perhaps doing some spring cleaning or gardening. Big black birds seem to be everywhere, some making a terrific racket. Have you wondered if these birds are crows or ravens? How do you tell the difference? The most apparent difference is that ravens are larger. Large male ravens can approach the size of a small chicken, and be very obvious if he struts across your mowed lawn looking for worms and insects disturbed by your mower. Crows often travel in groups, whereas ravens are usually seen in bonded pairs or with a adolescent. When the black birds fly low overhead, look at the tail. Crows have fan-shaped tails while ravens have wedge-shaped ones. Using your ears is a more sophisticated way to make the distinction as this video from the Cornell Ornithology Lab explains: