Bird of the Month: Ruffed Grouse (Bonasa umbellus)
More likely to be heard than seen in the Pacific Northwest
By Andy McCormick
Weight 1.3 lb (580 g)
AOU Alpha Code RUGR
A bird of the forest, the Ruffed Grouse populates a widespread area of southern and western Canada and the northern United States including the Pacific Northwest (Rusch, et al). It is found across Washington in areas of deciduous and mixed deciduous/coniferous forests of birch, alder, and poplar (Wald, Tweit, and Mlodinow). This grouse is common in low-elevation forests, but not always easy to see. In spring it is more likely to be heard.
Drum Roll, Please
The Ruffed Grouse makes soft, seldom heard sounds such as a squeal by the female and a hissing or Queet call by the male. However, the male makes a deep drumming sound in the spring. The drumming begins slowly and gradually accelerates to a drum-like roll. The sound is made as the bird rotates its wings forward and then quickly backward. This movement creates a small vacuum. As the air rushes in, it creates a small sonic boom. A drumming sequence takes about eight seconds and in that time the wings can beat up to 50 times (Rusch, et al). You can hear the drumming of a Washington Ruffed Grouse at the Macaulay Library.
The genus, Bonasa, of the Ruffed Grouse is monotypic, i.e., comprised of a single species. Bonasa is from the Latin bonasus, a species of wild ox. This grouse’s drumming was thought to resemble the call of a wild European bull. The species name, umbellus, from Latin umbella, an umbrella, refers to the umbrella shape of the feathers when the male raises the ruff around its collar. This ruff also inspired the common name.
Two Morphs: Red and Gray
The color difference in morphs of the Ruffed Grouse is most obvious in the tail. The red morph is more abundant in western Washington, and the gray morphs live east of the Cascade Range. Both morphs have a dark subterminal band across the tip of the tail. In males the band is solid. In females it is broken or blotchy in the center (Alderfer). Both sexes have a crest, which is more prominent when the grouse is alarmed or displaying.
Ruffed Grouse are permanent residents of their habitat and do not migrate. The female builds a nest, which is a simple depression on the ground, in thick habitat or next to a log or rock. It is lined with leaves, pine needles, and a few feathers. Usually 9-12 eggs are deposited. Incubation by the female takes about three weeks. The young leave the nest soon after hatching and will feed themselves. They can take short flights after a week or two, and can take longer flights after two more weeks (Kaufman).
Feeding in Trees
Ruffed Grouse make a diet of seeds, buds, twigs, catkins, and flowers, and will sometimes eat insects, spiders, and occasionally small snakes or frogs (Kaufman). In winter, they can be found high in trees eating the buds of branches.
Conservation methods are not needed for the Ruffed Grouse. Despite being regularly hunted as a game bird, Ruffed Grouse populations are affected more by predators than humans. Ruffed Grouse are on a cycle with snowshoe hares. Every ten years the snowshoe hare population crashes and their predators, usually Northern Goshawk and Great Horned Owl, turn to Ruffed Grouse (Rusch, et al). Some logging and fires can assist Ruffed Grouse, as they prefer successional forests to mature forests. However, when large tracts of forests are logged, Ruffed Grouse populations drop. North American population numbers are difficult to determine, but we know that the Ruffed Grouse is our most common and widespread grouse.
Photo: Ruffed Grouse, by Robert Howsen
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