“Everyone knows…that the autumn landscape in the north woods is the land, plus a red maple, plus a Ruffed Grouse. In terms of conventional physics, the grouse represents only a millionth of either the mass or the energy of an acre yet subtract the grouse and the whole thing is dead.” Leopold 1953b
The Ruffed Grouse is distributed throughout deciduous and coniferous forests of North America but is most abundant in early-successional forests dominated by aspens and poplars (Populus spp.). Resident in young forests as far north as central Alaska and as far south as northern Georgia, this species finds protection from predators in the canopy of young trees and in the thick understory of shrubs and saplings. Leaves, buds, and fruits of deciduous-forest plants constitute most of its diet. Buds and catkins of aspen, willows (Salix), and birches (Betula) are important winter food in Canada, Alaska, and the northern Great Lakes states.
This grouse bears a cryptic plumage of mottled gray, brown, buff, and black coloration. Its plumage occurs in two color morphs, gray and red (or brown), the tail showing the most noticeable difference in coloration. Intermediates between these occur, and the predominate morph varies geographically: the gray phase predominates in northern parts of the range, the red phase in the south. All Ruffed Grouse (except juveniles) have a prominent dark band near the tip of the tail and a tuft of feathers on the sides of the neck that can be erected into a ruff.
The Ruffed Grouse produces a variety of hissing, chirping, or peeping sounds, but is best known for the drumming sounds produced by the male. The drums are a series of progressively faster thumps produced by air rushing to fill the vacuum created under the wings when they are rapidly flapped in front of the body. The male drums throughout the year, but the vast majority of drumming occurs in spring, presumably to attract females and ward off other males.
The Ruffed Grouse is avidly hunted and, for this reason, harvests are monitored and controlled by bag limits, season lengths, and area closures. Harvest rates may be high in some areas; nevertheless, on local and regional scales Ruffed Grouse populations are usually limited by aging and succession of forests. Wildlife managers work with foresters and hunting groups to harvest small blocks of timber in ways that encourage reproduction of aspen and other early-successional plants. The Ruffed Grouse Society is the largest group of hunter-conservationists dedicated to enhancement of Ruffed Grouse populations and young forests that support many early-successional species.
Most mortality in Ruffed Grouse is caused by predators. Regular and synchronous irruptions of predators in Alaska and Canada are caused by the dramatic 8- to 11-year cycle in numbers of snowshoe hares (Lepus americanus). Scarcity of hares produces heavy predation on sympatric Ruffed Grouse and emigration of hungry predators. Cyclic declines of Ruffed Grouse populations in the Great Lakes region are associated with invasions of Northern Goshawks (Accipter gentilis) and Great Horned Owls (Bubo virginianus) from Canada.
Although most studies of the Ruffed Grouse have had a local focus, many produced widely applicable results. The population cycles in Ruffed Grouse have drawn much research attention. Long-term studies of cyclic populations were conducted in New York ( Bump et al. 1947 ), Minnesota ( King 1937 , Eng 1959 , Gullion and Marshall 1968 , Gullion 1984 ), Alberta ( Keith and Rusch 1989 ), and Wisconsin ( DeStefano 1982 , Small et al. 1991a , Balzer 1995 ). Researchers studied the habitat requirements of this important game bird in many places, such as Minnesota ( Gullion and Alm 1983 ), Alberta ( Rusch and Keith 1971a ), Idaho ( Stauffer and Peterson 1985a ), and Missouri ( Thompson III and Fritzell 1989 ). Important work on diet, nutritional ecology, and feeding was done in Minnesota ( Jakubas and Gullion 1991 ), Alberta ( Doerr et al. 1974 ), Tennessee ( Stafford and Dimmick 1979 ), Wisconsin (Guglielmo and Karasov Guglielmo and Karasov 1993 , Guglielmo and Karasov 1995 ; Guglielmo et al. 1996 ), and Virginia ( Servello and Kirkpatrick 1988 ). Harvest rates were a major focus of studies in Wisconsin ( Kubisiak 1984 , Rusch et al. 1984 , DeStefano and Rusch 1986 , Small et al. 1991a ) and Ohio ( Stoll and Culbertson 1995 ). In its day, the Ruffed Grouse investigation in New York ( Bump et al. 1947 ) was the most sustained and comprehensive study of any game animal in North America. It remains an outstanding work, even by today's standards, and is still the most important reference on the species.