Dryobates pubescens: industrious and adaptable.
The diminutive Downy Woodpecker – weighing less than an ounce, measuring 6 inches to tip of tail – lives here in Minnesota year-round, through the toughest winters. But they also thrive as far south as Florida and parts of the Southwest, with the same physiology. It’s no surprise that J. J. Audubon said the Downy “is perhaps not surpassed by any of its tribe in hardiness, industry, or vivacity”. This is one tough and adaptable little bird.
Wild creatures have two basic strategies to survive winter: find a substantial shelter, reduce your metabolism to the minimum, and sleep through it – or meet it head on, get out there and find food. Hunting or foraging while staying warm require intensive motion and brain activity. So if you’re small, you’re burning fuel like a jet engine.
A Downy’s body temperature is 107 F. They don’t put on fat for winter, but their metabolic rate increases by about 25% and their pectoral muscles enlarge, to do more heat-producing shivering. They’re still territorial, but reduce the area they defend to as little as 40 feet. At night they’ll huddle in small cavities and during the days (even the coldest ones) they will of course spend a lot of time searching for food. Interestingly, they join flocks of other species and circulate with them; I often see them with chickadees.
I put out suet in the winter, and of course they go for it, but I like to reflect on how they don’t really need us at all; they can always find insect larvae beneath bark. They’ve been here since the glaciers retreated, can handle the cold, and would probably be better off if we humans just moved away and stopped planting the wrong kinds of trees.
I enjoy watching their calm yet purposeful daily routines and am awed by the way evolution has equipped them to not just survive in these extreme conditions, but to do it with style, and even – now and then -to just find a sunny branch, fluff the feathers, relax and take it all in.