Birds and Blizzards
After a night of heavy snowfall during our recent nor’easter blizzard, we woke up to about two feet of new snow in the yard. We dug our way out the front door but before we started the long process of digging and scooping out the driveway, we did what every bird lover would do: we dug a path to the bird feeders and restocked them! It sure was something to see the chickadees, nuthatches, juncos, house sparrows, and the single white-throated sparrow that has persisted through the winter, coming in to the bird feeders despite being buffeted by the winds and driving snow.
Some birds actually do better with a deep, fluffy snow pack like the one we just received. Ruffed grouse (what many a Mainer refers to as “partridge”) are famous for snow burrowing in these conditions. As night falls (or perhaps also during the day under blizzard conditions) grouse will fly straight into a snow drift and burrow themselves under it. Here the temperature will stay well above what it is outside, especially as their body heat warms up the burrow. Consequently they will not have to burn extra energy to stay warm and will therefore consume fewer calories to stay healthy and increase their chances of surviving through the winter.
Ruffed grouse are not the only members of the broader grouse family that engage in this behavior. Ptarmigan, the Arctic and high-elevation mountain-dwelling grouse species (there are three species) that are all white in winter, are well known for this behavior as well. Incidentally, there are a handful of records of willow ptarmigan in Maine as these birds do migrate south, and hundreds of years ago may have been more frequent winter visitors. In the western U.S., the sage grouse is known to sometimes use snow burrows, and in Europe the capercaille does as well.
Among songbirds, the most well known species to use snow burrows is the common redpoll. In fact, one of the earlier references to snow burrowing in the species here in the U.S. (it had been observed in Europe as well) was from an observation on Mount Desert Island. More recently, author and naturalist Bernd Heinrich published a paper about his observations of a flock of redpolls snow burrowing in western Maine.
Snow buntings are another songbird that has been documented burrowing into snow under very cold and windy conditions; likewise boreal chickadees and their close relatives, the gray-headed chickadee or Siberian tit.
Many birds that do not burrow into the snow will roost in holes in trees or within the confines of a snow-draped conifer tree where there is protection from the wind and warmer conditions. We flushed a house sparrow from under a snow-capped shrub beside our house as we were shoveling the driveway after the blizzard.
Keep your eyes open and perhaps you will describe another species that makes snow burrows as more snow is apparently on its way!