You can only see straight ahead, but you can hear in all directions at once. Learning bird songs is a great way to identify birds hidden by dense foliage, faraway birds, birds at night, and birds that look identical to each other. In fact, when biologists count birds in the field, the great majority of species are heard rather than seen.
Learning calls and songs helps you in two ways: First, you can do a quick survey of what’s around before you’re even out of the parking lot. And second, when you hear something you don’t recognize, you know where to put your attention.
Owls and nightjars are obvious examples of the usefulness of hearing in identification. Another great example are the dozen or so confusing flycatchers in the Empidonax group. These birds look so similar they’re sometimes impossible to identify even in the hands of a bird bander with a precise set of measurement calipers. But all that uncertainty vanishes as soon as they open their mouths.
Five Tips for Beginners
Watch and listen
When you see a bird singing, the connection between bird and song tends to stick in your mind.