It happens every year in early May. I'm walking in the forest in the morning when my heart begins to beat wildly in my chest, faster and faster. It's a little frightening until I realize it's not me at all but the throbbing of an unseen bird deep in the forest, the ruffed grouse.
In the tangles along the creeks in the foothills throughout Southern Oregon you can hear, or rather feel, their presence. It's time for courtship.
The ruffed grouse is a mottled brown bird the size of a small chicken. It has a short crest and black patches of feathers on the neck of the male that can be raised when drumming. These are the ruffs that give the bird its name. The tail has a broad black band near the tip. The rest of the tail is either reddish brown or silver gray depending upon the individual. I have seen more with gray tails than brown in our area.
Some grouse, such as the sooty grouse (formerly the blue grouse), produce a deep, booming call with the aid of inflated throat pouches. This can sound very much like the call of an owl. A sooty grouse will ascend a tree, usually a large Douglas fir, on a ridge. Sitting on a large limb, the male will inflate the bright yellow throat pouches and a complementary set of small but brightly colored wattles over the eyes. From its chosen perch, it booms deliberately. "Whump-whump-whump-whump!" Being polygamous, or more precisely polygynous, this performance continues relentlessly throughout the spring each morning until it is time to scratch up breakfast. There is surely one more female in need of his attention. The term "polygyny" describes a relationship between one male and more than one female. "Polyandry" is the reverse. "Polygamy" is the general term applied to both.
Now back to my "heart problems." The ruffed grouse produces the seductive sounds of spring in a very different manner than the sooty grouse. The stage for the ruffed grouse is usually closer to the ground, often a stump or fallen log. From his vantage point he stands tall and with a quick flap of his wings he cups air and sharply presses it to his body producing a very low-frequency "thupp!" This is followed but a second "thupp" and a third and a fourth, each delivered quicker than the last until the wings are a blur. Now he pauses. Any female grouse impressed? Surely one? No? The performance is repeated.
The sound is such low frequency that it is below the range of hearing of the great horned owl. Not a bad strategy. To be able to communicate with females and other males without alerting one of your principal predators is a tremendous advantage.
Other birds communicate with non-vocal sounds, as well. Snipe winnow, nighthawks boom and hummingbirds whine or pop, depending upon the species. I'll have more to say about these later.
If you wish to hear ruffed grouse drumming, I recommend an early-morning outing up Wagner Creek about milepost 4 or 5 or along the side roads and logging roads in the Applegate near Ruch. Good luck ... and really, your heart is fine.
Stewart Janes is a biology professor at Southern Oregon University. He can be reached at email@example.com.