The ruffed grouse is a non-migratory bird (4), and despite being a swift and acrobatic flier (6), this species spends most of its time on the ground (4), tending to walk rather than fly (6). If disturbed, the ruffed grouse may explode into flight (4), but these bursts of flight are generally short-lived (5) (6).
An alarmed ruffed grouse, particularly a female with chicks, emits a clucking or whining sound (5). A variety of hissing, chirping and peeping sounds are also produced by this species (2).
The omnivorous ruffed grouse has a varied diet, and consumes leaves, buds, seeds and fruit (4) (6) (8), as well as insects (4) (8) (11) and other invertebrates (3) (5). In the winter, the primary food source for this species is buds, particularly aspen catkin buds (1) (2) (3) (5) (6) (8) which are high in sugar and protein (6). Poplar (7) (11) and birch are also frequently eaten (3). In the spring, the ruffed grouse feeds on the new leaves and shoots of a variety of plants, including trees, shrubs and dandelions (3) (5). Ripening fruits, including blackberries and blueberries (3) (5), form the basis of this species’ diet in the summer (7) (11). Ruffed grouse chicks feed on small insects and spiders (5) (7) (11).
The male ruffed grouse attracts females with a rather noisy courtship display involving ‘drumming’, which is performed on a raised platform such as a log (2) (3) (4) (5) (6) (7) (8) (11). The male bird rapidly flaps its wings in front of its body, creating a loud thumping noise (2) (5) which can be heard more than a quarter of a mile away (3) (5). As the female approaches, the male struts along the log (5) (8) with its tail fanned out (3) (8) (11) and its ruff and crest erect (5) (11), hissing while dragging its wingtips along the ground (3).
Mating generally takes place in April and May (3), but males also drum at other times of the year as a means of defending their territories (2) (3) (6). No genuine pair bond is formed in the ruffed grouse (5), and a male may mate with several hens during the breeding season (3) (5). The male plays no part in nesting or the rearing of the chicks (3).
The female ruffed grouse builds a nest on the ground (3) (4) (11), usually a hollow scrape lined with dry leaves (3) (5), pine needles and some feathers (3) (11). The nest of the ruffed grouse is usually located at the base of a tree or near a fallen log (5) (11) in an area which is well camouflaged by low vegetation (5).
The female ruffed grouse lays between 9 and 12 eggs (3) (5), which are buff-coloured with brown speckles (3) (5) (11). The eggs are incubated for approximately 24 days (5) (11), and the precocial chicks (3) (5) are able to feed themselves straight away (3) (11). Ruffed grouse chicks fledge after about 12 days (5) (11).