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Ruffed Grouse Life History

Habitat

ForestsMixed-age groves of aspen, spruce, and birch make ideal habitat for Ruffed Grouse in the northern part of their range. Farther south, grouse inhabit deciduous forests of oaks, hickories, and pines, while in the Pacific Northwest you can find them in riparian habitats. Because young stands of trees are important for both cover and food, grouse populations are higher in areas where logging, burning, and other disturbance create early-successional forests. Populations of Ruffed Grouse are lower in mature forests and in small patches of woods surrounded by agricultural lands.Back to top

Food

OmnivoreRuffed Grouse feed almost exclusively on vegetation, including leaves, buds, and fruits of ferns, shrubs, and woody plants. In fall, soft fruits and acorns become an important part of the diet. Ruffed Grouse’s ability to digest foods high in cellulose make it possible for them to survive harsh winter conditions in the northern part of their range, where they feed on buds and twigs of aspen, birch, and willow. In winter, birds in the south forage on leaves and fruit of greenbrier, mountain laurel, Christmas fern, and other green plants. Although insects and other invertebrates make up only a small part of the adult grouse’s diet, chicks 2 to 4 weeks old depend on this protein-rich prey. Back to top

Nesting

Nest Placement

GroundAfter mating, female Ruffed Grouse choose a nest site at the base of a tree, stump, or rock in areas with sparse ground cover that give a clear view of predators. Nests may also be built in brush piles, or in the bases of partially open, hollowed-out stumps.

Nest Description

The Ruffed Grouse’s nest is a simple, hollowed-out depression in leaves on the forest floor, reaching up to 6 inches across and 3 inches deep. Females build the bowl-shaped nest and typically line the bowl with vegetation that they pluck from the edge of the nest site.

Nesting Facts

Clutch Size:9-14 eggs
Egg Length:1.5-1.6 in (3.78-4.14 cm)
Egg Width:1.1-1.2 in (2.9-3 cm)
Incubation Period:23-24 days
Egg Description:Eggs are milky to cinnamon buff sometimes spotted with reddish or brown.
Condition at Hatching:Precocial; chicks hatch covered in sandy to brown down with a triangular patch of black feathers around the ears. Chicks can walk and feed themselves within 24 hours of hatching.
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Behavior

Foliage GleanerThanks to their cryptic coloration and slow, deliberate movements, Ruffed Grouse can be difficult to spot as they forage on the forest floor or walk along the low branches of trees and shrubs to pluck berries and buds. The grouse’s habit of burying itself in soft snow to roost can lead to surprising encounters for snowshoers or skiers when the birds erupt from beneath the surface. When displaying for females or defending territory, the male grouse stands atop a log, rock, or low dirt mound with crest, ruff and tail erect, puffing up to nearly double its normal size and beating its wings to create a rapid-fire drumming sound. A drumming male will often trigger a response in a nearby male defending its own territory. Following the elaborate display, mating lasts only a few seconds—females then go on their way to build a nest at the base of a tree or rock and raise the young on their own. Although Ruffed Grouse are normally solitary, small groups of unrelated birds may form in fall or winter to take advantage of productive feeding spots.Back to top

Conservation

Low Concern

Ruffed Grouse are fairly common and widespread, and their populations have held steady between 1966 and 2019, according to the North American Breeding Bird Survey. Partners in Flight estimates the global breeding population at 18 million and rates them 8 out of 20 on the Continental Concern Score, indicating a species of low conservation concern. The grouse’s immense popularity as a game bird has led to controls on season length, bag limits, and area closures, as well as to extensive efforts to improve habitat through management practices that encourage early successional forest. The Ruffed Grouse Society partners with government agencies in programs to expand grouse habitat through land purchases and targeted management. Habitat for Ruffed Grouse has declined where forests have matured due to fire control and limits on logging. Pesticide use can affect insect populations that chicks rely on.

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Credits

Partners in Flight. (2020). Avian Conservation Assessment Database, version 2020.

Rusch, Donald H., Stephen Destefano, Michael C. Reynolds and David Lauten. (2000). Ruffed Grouse (Bonasa umbellus), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.

Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski Jr., K. L. Pardieck, J. E. Fallon, and W. A. Link (2019). The North American Breeding Bird Survey, Results and Analysis 1966–2019. Version 2.07.2019. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.

Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.

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Learn more at Birds of the World