Winter birding for me often means spending a good amount of time in overgrown weedy fields with scattered shrubs and blackberry thickets. The species diversity is usually quite high, and most species are fairly cooperative in letting birders get decent looks.

I recently checked out some nice fields off Harrisburg Road at the Harrisburg Road Sports Complex. Not unexpectedly, it soon became evident that white-throated sparrows and song sparrows were very numerous.

In winter sparrow fields with thickets, these two species will dominate. But birds attract more birds, so when I find large numbers of common birds I always go through them slowly to find something a bit more interesting.

A few swamp sparrows gave themselves away with their calls. I caught a few glimpses of them as they skulked in the thicker lower growth. Some loud "chip" notes let me know that fox sparrows were there too. I soon found them on the tops of sumac heads feeding on the seeds.

Fox sparrows are large, robust sparrows, handsomely adorned in foxy red and gray tones. I even found a couple of hermit thrushes there, lured out of the woods by the promise of an easy meal. A territorial Northern mockingbird tried to chase the feeding birds away but ended up just exhausting itself.

A nasal, complaining call gave a house wren away in the thicker grass. It was answered by two others in other ends of the field. House wrens are conspicuous in the breeding season in residential yards but become more retiring in the winter, choosing weedy patches to pass the colder months. Their tiny cousin, the winter wren, was also present.

A patient birder is usually rewarded with something a little more exciting in a habitat like this, and that day was no exception for me. After an hour of walking back and forth in essentially the same area, I spied a small greenish bird with yellow underparts in a thicket.

It turned out to be a common yellowthroat, a species that is scarce in our area in the winter. That was enough for me to schedule a return visit in the future to see what else might be hiding out there.