If you have put on snowshoes and gone outside to enjoy the winter lately, you are not alone. Some wild animals, like the snowshoe hare, have naturally large feet to help them navigate across deep powder. But did you know that one of our local birds also has snowshoe feet?
The Ruffed Grouse, also known as the partridge, has several structures and behaviors that help it survive as a year-round resident of Massachusetts. One of those adaptations is to grow comb-like protrusions on its toes in the fall, triggered by the shortening day length. These little spikes emerge laterally, widening the surface area of each toe. By creating a larger foot print, the grouse is able to walk across the snow without sinking deeply, thus conserving energy at a time of year when that is critical to survival. The "snowshoes" fall off the toes by April or May when they are no longer needed.
Ruffed Grouse are about the size of a chicken and come in both reddish and gray-brown color phases. They spend most of their time walking rather than flying. As they walk across the snow, they leave tracks which are easy to identify. Their three primary toes splay out, forming almost an upside-down T shape, about 2" in length. They also tend to put one foot in front of the other, creating a straight line trail.
In addition to their tracks, grouse leave other tell-tale signs behind. Their droppings or scat reflect their vegetarian diet, being made up of plant fiber. This time of year, those fibers come primarily from tree buds, especially from aspen and birch, their preferred winter food.
If the snow is at least 10" deep and fluffy, however, grouse find a warmer place to spend the night . . . under the snow. The grouse plunges into the fluffy snow, which traps air and provides insulation from bitter cold and wind. They dig further into the cavity so they are completely out of sight. The snow will keep the birds' body heat close to them. These burrows never get below 20 degrees. That may not seem warm, but compared to many of the sub-zero nights we've had lately, 20 seems balmy-- and there's no wind chill under the snow.
These sleeping tunnels also provide protection from predators.
If you are lucky enough to find one of these burrows, look for wing prints on either side of it which indicate where the grouse emerged and took flight. I've heard tales of skiers and hikers trekking through the winter woods and becoming startled by a grouse bursting forth from its subnivean hideout. That's a nature experience not quickly forgotten!
Another adaptation Ruffed Grouse have is atypical feather placement. Unlike many other birds, they grow feathers on their legs which help keep them warm. Feathers also grow around their beaks and cover the nostrils. These warm the air when the bird inhales, and they act like the hairs inside our noses.
If all of these structures and behaviors are successful, and the grouse survives until spring, you may be able to hear one of the most prominent clues of the Ruffed Grouse's presence. When other birds are sharing melodious songs to attract a mate, the male grouse finds a hollow log or stump to stand on and rapidly beats his wings back and forth. The sound of the wing beats starts slow and low, building to a "blurred crescendo" as the Cornell Laboratory of Ornithology describes it. To listen to this sound, visit www.allaboutbirds.org/guide/ruffed_grouse/sounds. The male hopes a female grouse will find this sound enticing, and they will produce more grouse.
Discovering the signs and sounds of grouse are much easier than seeing the well camouflaged and secretive bird, but it's great to find clues of their presence. Early colonists hunted and used them for food to the point of near extinction -- so we are lucky to share our state with this now common survivor.