12/18/2025
The ultimate birding experience in southern Wisconsin happens after a December snow. First the snowplow operators clear the roads to make travel safe for us motorists. Next they remove the snow from the road shoulders. People know that snow-free shoulders are safer for winter driving. The birds know that the exposed sod and gravel become a major attraction, like a magnet for our winter sparrows. Do our readers know why especially the sparrows flock to these roadside attractions?
Let's first determine what types of sparrows we are seeing. Subtract Wisconsin's dozen or so species of summer sparrow residents which have long since migrated south. Then, know that Southern Wisconsin receives two northern sparrow species which migrate here to spend the winter. The most well known and loved of these is the dark-eyed junco. The snow bird! It's contrasting colors of dark grey above to the white underneath, as if it were dipped in snow, light up the hearts of many a birder. Another key field mark, the white outer tail feathers, the junco flashes on and off while feeding and flying. Its winter calls are simple and unique yet difficult to describe. Tip: Put out a backyard bird feeder with some white millet or cracked corn. With a little luck you will have junco's calling for you to hear!
Coming down from its northern breeding territory, the American tree sparrow spends the winter here too. The warm colors of brown and chestnut, the rufous cap and eye stripe, and the white wing bars adorn it's upper body parts. The American tree sparrow also shows a dark spot in the center of its greyish breast. The winter snows help reveal the wonderful feeding habits of these sparrows. Walk into a prairie, or even just a weedy field after a snowfall. Be a detective searching for clues. The dried flowers and grasses leave their seeds as signs in the fresh snow. The sparrows leave their footprints as signs, tracks they have left while searching for the seeds!
Now back to our question. The roadside at first glance does not seem like suitable habitat for any bird, let alone our winter sparrows. What would cause these bare scrapes, made by humans but for a different reason, to attract so many winter sparrows? Their small size tells part of the story, with the other part being told by their feeding habits. As ground feeders, both the junco and the tree sparrow require small seeds to survive the winter. Their small feet cannot get through the deep snow on their own. The roadside offers tiny seeds from weeds and grasses. A little bird biology is needed for the final piece of the roadside puzzle. Birds eating hard seeds need help grinding their food. The roadside offers exposed patches of very small sand and gravel particles. Once swallowed, the grit meets the seeds in the bird's stomach, called a gizzard, where the seeds are ground for digestion.
And there you have it. A wonderful bird story you can witness yourself. So get out and explore the world of birds.
