Crows and Ravens - Can You Tell Them Apart?

Crows and ravens have these really, really impressive vocal repertoires. Part of the reason that they can make such a wide variety of sounds is because they actually have independent muscle control on either side of their syrinx. There are definite tools that you can accumulate, and you can get really good at it. For example, carrion crows are the main crows that yo over there are one size. Ravens are quite a bit bigger than carrion Crows. And rooks are, whence, once they've had their first adult molt, are really easy to distinguish as they lose all the feathers at the base of their beak.