Based on 2,230 research-grade iNaturalist observations in Colorado, Dusky Grouse is most often recorded in August; in Colorado it behaves like a summer visitor / breeder. It ranks #40 among birds recorded in the state in our data.
Dendragapus obscurus
Dusky Grouse in Colorado by month
Bars show research-grade observations per month. They mix true seasonality with how often people are outdoors, so treat small numbers with caution.
Also seen in Colorado in August
Black-billed Magpie

Broad-tailed Hummingbird

Red-tailed Hawk

Mallard

Steller's Jay
Swainson's Hawk

Wild Turkey

Northern Flicker
Places to look in Colorado
White River National Forest
Denver Botanic Gardens
Rio Grande National Forest
National ForestSan Juan National Forest
Roxborough State Park
Mancos State Park
FAQ
When does Dusky Grouse appear in Colorado?
Mainly May–September, with the most records in August.
How common is Dusky Grouse in Colorado?
It ranks #40 by number of iNaturalist observations among birds in Colorado (2,230 records in our sample).