Ruffed Grouse

Ruffed Grouse

NPS Photo / R. Wang

Length: 15.8-19.7 in (40-50 cm)
Weight: 15.9-26.5 oz (450-750 g)
Wingspan: 19.7-25.2 in (50-64 cm)

Ruffed Grouse (Bonasa umbellus) are beautifully patterned with dark bars and spots against either a reddish-brown or grayish background. Dark bars extend down the side of the neck and widen on the belly. Their tail features fine barring, with one prominent black band near the tip.

Habitat

These birds typically inhabit mixed deciduous and coniferous forest interiors with scattered clearings. They are also found along forested streams and in areas recovering from fire or logging.

Behavior

Look for Ruffed Grouse foraging on the forest floor for seeds and insects. Males display by producing a deep, airy drumming sound by beating their wings while standing on a log. In spring, lone birds are common; by summer, females with broods can be seen. In winter, they form flocks and often feed on the buds of deciduous trees.

Diet

Ruffed Grouse primarily feed on vegetation, including leaves, buds, and fruits of ferns, shrubs, and woody plants. In the fall, soft fruits and acorns become significant components of their diet.

Nesting

After mating, females select nesting sites at the base of trees, stumps, or rocks in areas with sparse ground cover for predator visibility. They may also build nests in brush piles or the bases of partially hollowed-out stumps.

Eggs and Incubation

Ruffed grouse eggs are generally milky to cinnamon buff, sometimes spotted with reddish or brown. The female incubates 9-14 eggs for 23-24 days. The chicks are precocial, able to walk and feed themselves within 24 hours of hatching.

Unique Adaptations and Dietary Habits

Ruffed Grouse can digest bitter, often toxic plants that many birds cannot handle. The levels of defensive plant compounds in the buds of quaking aspen—a key winter food source—reflect the cyclical rise and fall of grouse populations: they are lowest when grouse densities are increasing and highest when numbers are declining.

Ruffed Grouse do not migrate and remain year-round residents in their habitat. During winter, the toes of Ruffed Grouse develop projections that resemble combs, believed to function as snowshoes, aiding their movement across snow-covered ground.