Ruffed grouse
| Ruffed grouse Temporal range:  | |
|---|---|
| A displaying male at Seney National Wildlife Refuge, Michigan, and a female at Algonquin Provincial Park in Ontario | |
| Scientific classification | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Chordata | 
| Class: | Aves | 
| Order: | Galliformes | 
| Family: | Phasianidae | 
| Tribe: | Tetraonini | 
| Genus: | Bonasa Stephens, 1819 | 
| Species: | B. umbellus | 
| Binomial name | |
| Bonasa umbellus | |
|    resident range | |
| Synonyms | |
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The ruffed grouse (Bonasa umbellus) is a medium-sized grouse occurring in forests from the Appalachian Mountains across Canada to Alaska. It is the most widely distributed game bird in North America. It is non-migratory. It is the only species in the genus Bonasa.
The ruffed grouse is sometimes incorrectly referred to as a "partridge", an unrelated phasianid, and occasionally confused with the grey partridge, a bird of open areas rather than woodlands.
The ruffed grouse is the state game bird of Pennsylvania, United States.