American Tree Sparrows usher in Old Man Winter

Freshly burned over, Daughmer Savanna in Crawford County awaits botanical renewal with next year's growing season. Prairie ecosystems and fire are yin and yang, the fire performing many roles: keeping woody plants from choking out sun-loving prairie plants, discouraging nonnative invaders, providing a big infusion of nutrients to the soil, and heat-scarifying the seeds of plants.

I had chance to drop by here last Saturday, unbeknownst to me, hot on the heels of a controlled burn that was orchestrated by ODNR's Division of Natural Areas. The Division stepped in and purchased this gem a few years back, when it went up for auction. Daughmer Savanna is one of the finest prairie savannas left in Ohio, and one of the few that remain. About 99.9% of this habitat has been destroyed. Today, the Crawford County Park System oversees its management. If you ever get the chance, stop by and check out this relict of our prairie past.

Controlled burns seldom singe all of the vegetation, and in corner of the prairie the standing goldenrod had attracted one of my favorite birds, the American Tree Sparrow, Spizelloides americana. I heard their delicate notes before seeing the birds - the calls of a distant flock sounds like icicles falling and shattering. Occasionally a bird would deliver a truncated version of its song, a beautiful somewhat melancholy series of whistled notes.

This was the first weekend that I've noticed this harbinger of winter in substantial numbers. Another sparrow, the Dark-eyed Junco, often gets props for being the "snowbird", but in my book the tree sparrow is the true snowbird. When they show up in numbers, winter with its frosty bite and sleet and snow will not be far behind.

Map courtesy Birds of North America Online.

American Tree Sparrows breed far to our north, beyond the range of most Homo sapiens. For such a common wintertime resident in the northern and central states, it is a surprisingly enigmatic bird insofar as its breeding ecology goes. Tree sparrows nest in places where most people don't go; indeed, can't go in most cases.

The plucky little sparrows are common at backyard feeders when they come south, but feeders of course are a recent source of food for the birds. I have noticed time after time, over many years, their fondness for the fruit of goldenrod when encountering the birds in places wilder than the backyard. Goldenrods in the genus Solidago produce huge crops of seeds which are high in protein and fat, and the sparrows thrive on this fruit. I suspect goldenrods do the heavy lifting when it comes to supporting wintering American Tree Sparrows. We may temporarily entice the visiting northerners from the goldenrod patches with our feeders, but given a choice I think most tree sparrows prefer the wild crops of seeds.