Wondernose: What bird has three different sets of plumage for three different seasons?

Wondernose: What bird has three different sets of plumage for three different seasons?

You and I consider it normal to own one coat for winter, one for spring and fall, and one for summer. But that’s not so common for the birds. Yes, a few birds do have two sets of plumage, but three is rare. Not only does our mystery bird have three “coats,” but the...