"Grouse Feeding on Aspen Buds"
by Kevin Strauss

While many of our northwoods birds have left for the winter, some hardy species are settling into the season. One species, the ruffed grouse (Bonassa umbellus) has such a diverse diet that when the seasons change or a foot of snow covers the ground, they just switch foods. Throughout the year, grouse feed on as many as 600 species of plants and mushrooms and 300 species of insects. This flexibility makes it easy for gruse to find food no mater the weather or the time of year. What's more, as the snow flies, grouse grow comb-like snowshoes on their feet that let them walk on top of snowdrifts without sinking in too deeply.

These grayish-brown chicken-like birds will spend much of December feeding in aspen trees, feeding on the nutritious buds on tree branches. One researcher in Minnesota found that aspen buds make up 87 percent of the winter grouse diet, with the buds of trees like paper birch and bigtooth aspen making up the difference. It seems to be no accident that the ranges of ruffed grouse and quaking aspen are almost identical across North America. Grouse numbers are low this year but should soon be on the upswing over the next five years. Grouse, like snowshoe hare, seem to follow a 10-year boom and bust population cycle. On years when grouse numbers are high, one might think that they would have a negative impact on aspen trees, and they do. If grouse eat most of the leaf buds or consume most of the aspen's male flowers (catkins) in the spring, aspen tree reproduction can slow almost to a stop. But aspens are not known to give up that easily.

Researchers have found that quaking aspens react to browsing by grouse, deer and other animals by producing chemicals in their buds that herbivores can't digest. What is more, there is some evidence that even aspen trees that haven't been grazed begin producing these defensive chemicals. Scientists have yet to figure out what triggers these changes in undamaged trees, but it is possible that the tree communicate by airborne pheoromones or through chemicals in their root systems. While some people term grouse as 'dumb' birds who walk into traffic or crash into windows, others take a more historical view.

Among the Ojibwe who have lived in the area for hundreds of years, some see the grouse as a bird who takes pity on the humans. Some stories describe grouse as birds who will offers themselves up for food, so that the people do not starve. From my perspective, any bird who can survive a northwoods winter without heated houses and fleece jackets, must be a lot smarter than we think.

The Ely Timberjay