If you spend much time in forested regions of Canada and parts of the US, you’ve probably heard a curious drumming sound as the winter months draw to a close:
The drumming starts out slow, but speeds up toward the end, sounding a bit like an engine starting up in the distance. This is the sound of the male Ruffed Grouse performing a courtship display. He beats his wings in the air, creating a thumping sound as the air rushes into the vacuum left by the wing movement. If all goes well, nearby females will be attracted by the drumming and will move in to briefly mate with the male.
This popular game bird is another perfectly-adapted winter resident. Ruffed Grouse can digest fibrous, woody plant material, a plentiful food source during even the harshest winters. They also roost in the snow, burrowing down to insulate themselves from the cold air. Perfectly camouflaged, they explode out of the snow if a threat comes too near, leaving distinctive marks in the snow and sometimes heart palpitations in unsuspecting passers-by.
The Cornell Lab of Ornithology captures the sound of the Ruffed Grouse drumming and provides a great explanation of this event:
Photo: Hamilton Greenwood
Sound clip: Jonathon Jongsma via Wikimedia Commons