As winter descends and the days become cold and short, most of my birdwatching becomes rather narrowly focused on the feeders outside my front door. A walk through my woods in winter, although lovely in its own right, tends to yield fairly few birds. If I’m lucky, I might come across a noisy flock of Golden-crowned Kinglets, Black-capped Chickadees, and Brown Creepers. Just as easily, though, I can spend an hour wandering through the snow in absolute silence; the trees seem empty of birdlife.