Last Updated on Monday, 14 December 2009 13:36
Common Name: Blue Grouse
Also referred to as: Dusky grouse, fool hen, mountain grouse, pine grouse, Richardson grouse, sooty grouse
Genus species: Dendragapus obscurus (Dusky Grouse), Dendragapus fuliginosus (Sooty Grouse)
Recognised subspecies: D. o. obscurus (Say), D. o. sitkensis, D. o. fuliginosus (Ridgway), D. o. sierrea, D. o. oreinus, D. o. howardi, D. o. richardsonii, D. o. pallidus
- Total length: Adult male, 470-572 mm; adult female, 437-478 mm.
- Wing chord length: Adult male, 196-243 mm; adult female, 178-235 mm.
- Tail: Adult male, 131-201 mm; adult female, 111-59 mm.
- Weight: Male, 1260-1275 g; female, 820-1020 g.
- Breeding male plumage is commonly light blue to brownish-gray including white areas on the breast, undertail coverts and along the neck rosettes. Head and tail retrices are a darker blue-gray with the exception of a light gray terminal tailband shared by both sexes. Air sacs of obscurus are reddish-purple and vary in tinge with expansion and excitement, whereas fuliginosus air sacs include more yellow colouration. Eye combs range from yellow to red, with richardsonii normally exhibiting yellow, and normally orange for obscurus; however, colouration may change based on stress or sexual excitement.
- Female fuliginosus mottled brown back with plain grey abdomen. Female obscurus are similar to the fuliginosus but paler, with a squarer, closed tail feather appearance and either lack or virtually lack the terminal gray band on the tail feathers.
- Dusky chicks are grayish, while Sooty chicks are yellowish.
North American Distribution
Movements and Migratory Habits
Diet and Foraging Strategy
North American Distribution:
- Found in many major mountain ranges in western North America, southern Yukon, western Alberta, through much of British Columbia, along the west coast from south east Alaska to northern California, coastal islands including Vancouver and Queen Charlotte islands, resident of foothills and mountain areas of western Montana, northern Idaho, western Wyoming, north east Nevada, central Utah, western Colorado, and north central New Mexico.
- Dusky Grouse are found in the Rocky Mountain and Foothills Natural Region (can be found from the headwaters of the Smokey River to the U.S. Border).
- Open forest stand habitats (coniferous or mixedwood) are often preferred during the breeding season (crown closure of 15-50 %) with patchy shrub layers, scattered openings, and trees occurring in clumps.
- The breeding range for interior subspecies may be the fringe areas of montane forests (open stands), grasslands/shrub areas, and alpine/subalpine areas.
- The breeding range for coastal subspecies may include habitats at sea level (old growth forests with canopy gaps and young forest in burned or logged areas), open montane forests, and alpine/subalpine areas.
- An important element of the breeding range seems to be a well-developed forb/grass/shrub layer.
- Montane forests provide the primary winter range with the grouse, spending most of the time in coniferous trees (often the largest tree available).
- This grouse often winters at high elevations.
- Male home range size varies from 0.4-3.2 ha and females from 2.0-17.4 ha.
Movements and Migratory Habits:
- Adults are often active (foraging) throughout the day with peaks of feeding activity occurring in the early morning and towards the evening.
- Grouse often roost at night (on the ground or in trees).
- Fall migration is usually from the more open breeding range to conifer stands which tend to be more dense, this often means moving to higher elevations.
- Wide variation of arrival at the breeding range (factors being weather and geographic location). Arrival times may be from late March to mid April.
- Return to the winter range from late June to early September.
- May move as small flocks, pairs, or singles with movements occurring often at sunrise or sunset.
- Migration movements may range from 1.6-16.1 km (distances of 62.8 km have been observed).
Diet and Foraging Strategy:
- Winter diet consists primarily of coniferous needles from trees such as firs (Abies spp.), Douglas-fir (Psuedotsuga menziesii), pines (Pinus spp.), and mountain hemlock (Tsuga mertensiana).
- Summer diet consists of a variety of fruits/berries, seeds, green leaves, flowers, insects, and conifer needles. Shrubs used for foraging include currants (Ribes spp.), blackberries (Rubus spp.), huckleberries (Vaccinium spp.), and bearberry (Arctostaphylos uva-ursi).
- Chicks may feed primarily on insects, an important dietary component during the first month.
- Males are polygamous, often mating with more than one female during a single breeding season; however, close pair bonds may develop under certain situations.
- Males establish a territory upon arrival to the breeding range. Displaying may begin as early as late April, with the peak of activity in early May to early June. Timing of breeding may vary between years and location (may relate to time of arrival on the breeding range and weather conditions).
- Territorial assertion by the male is achieved by hooting (a combination of postures, movements, and vocalization). Dusky Grouse hooting calls are hardly audible more than 45 m away, while Sooty Grouse hooting calls can carry several hundred metres.
- Dusky Grouse often call from the ground, but may utilize trees, while Sooty Grouse will usually call from tree limbs.
- During hooting, the male erects neck feathers (white based feathers) to expose a gular sac, creating a rosette pattern. The wings are slightly drooped and the tail feathers are raised and spread.
- Other displays by the male include strutting and flight displays.
- Nests are usually a shallow scrape in the ground 4-5 cm deep and approximately 17 cm in diameter (often located under small conifers, under shrubs, or close to logs or stumps).
- Nest bowls are often lined with leaves, needles, moss, twigs, and bark (material within reach of the nest).
- Egg laying may occur in late April, with hatch dates ranging from mid May to mid July.
- Clutch size ranges from 5-10 eggs
- Egg size commonly 5.2 x 3.6 cm.
- Egg colour may vary from pale pinkish buff to beige, often speckled or blotched with darker shades of browns.
- Incubation and brooding by the female only.
- Hatch is synchronous; all chicks often hatch within 24 hours (chicks are precocial).
- Broods usually disperse in late summer to fall.
- Federal: Not listed.
- Provincial: Secure.
Blue Grouse photo © 2008 Johnye Burns. Retrieved from www.istockphoto.com/stock-photo-7504955-blue-grouse.php on 18/09/09. Used with permission.
Alberta Sustauinable Resource Development (ASRD). 2008. Search species and status category: Blue Grouse. http://www.srd.gov.ab.ca/fishwildlife/speciesatrisk/statusofalbertawildspecies/search.aspx. Accessed 29 May 2009.
Blackford, J. L. 1963. Further observations on the breeding behaviour of a Blue Grouse population in Montana. The Concord 65: 485-513.
Federation of Alberta Naturalists. 2007. The Atlas of Breeding Birds of Alberta: A Second Look. Federation of Alberta Naturalists, Edmonton, Alberta, Canada.
Johnsgard, P.A. 1973. Grouse and Quails of North America. The University of Nebraska Press, Lincoln, Nebraska, USA.
Rogers, G. E. 1968. The Blue Grouse in Colorado. Colorado Game, Fish and Parks Department Project W-37-R.
Schroeder, R. L. 1984. Habitat Suitability Index Models: Blue Grouse. U.S. Fish and Wildlife Service Biological Report 82 (10.81), Washington, D.C., USA.
Zwickel, F. C. and J. F. Bendell. 2005. Blue Grouse (Dendragapus obscurus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved May 24 2009, from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/015 doi:10.2173/bna.15
Zwickel, F. C. 1977. Local variations in the time of breeding of female Blue Grouse. The Condor 79: 185-191.