Population status

Dusky Grouse
(Dendragapus obscurus)

There is little information to inform the determination of population status for Dusky Grouse in Canada. The species is not often reported on the Breeding Bird Survey (BBS), since its territorial calling season peaks in April, well before the survey begins and because there are few routes within its breeding range. Furthermore, the estimated trend for Canada relies on the species’ range-wide trend (i.e., the average trend across the BBS survey area, including in the United States) because there are relatively few observations of the species in any one region. Christmas Bird Count results are not used here because of the extremely poor precision and small number of Canadian count circles included in the analysis. Considering the existing BBS results alone, the Dusky Grouse population is best assessed as having shown a little overall change in since 1970, although the reliability of this assessment is considered to be low. Currently, the species is at an acceptable level relative to its national population goal (see BBS Canada graph below).

Population goal and acceptable levels of variation

Species/group	Goal	Lower level	Upper level
Dusky Grouse	Mean abundance (2008-2012)	10th percentile of observed abundance (1970-2012)	Not applicable

Breeding Bird Survey (BBS) - Canadian analysis

Additional information on: Breeding Bird Survey (BBS) - Canadian analysis

View definitions of table column headings being used by: Breeding Bird Survey (BBS) - Canadian analysis

Table 1: Population trends by geographic area
Geographic area	Time Period ^{Table 1 - footnote 1}	Annual trend ^{Table 1 - footnote 2}	Limits
Geographic area	Time Period ^{Table 1 - footnote 1}	Annual trend ^{Table 1 - footnote 2}	Lower	Upper
Canada Select to view graph of the geographic area: Canada 1971-2016; Breeding Bird Survey (BBS) - Canadian analysis	1971-2016	-0.3	-12.2	4.4
North America Select to view graph of the geographic area: North America 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis	1970-2016	2.1	-1.2	4.8

Christmas Bird Count (CBC)

Additional information on: Christmas Bird Count (CBC)

View definitions of table column headings being used by: Christmas Bird Count (CBC)

Table 2: Population trends by geographic area
Geographic area	Time Period	Annual Trend ^{Table 2 - footnote 1}	Limits
Geographic area	Time Period	Annual Trend ^{Table 2 - footnote 1}	Lower	Upper
Canada Select to view graph of the geographic area: Canada 1970-2016; Christmas Bird Count (CBC)	1970-2016	22.4	-11.6	48.9
North America Select to view graph of the geographic area: North America 1970-2016; Christmas Bird Count (CBC)	1970-2016	17.9	-7.8	28.7

References

Banks, R.C, C. Cicero, J.L. Dunn, W.W. Kratter, P.C. Rasmussen, J.V. Remsen, Jr., J.D. Rising and D.F. Stotz. 2006. Forty-seventh supplement to the American Ornithologists’ Union check-list of North American birds. Auk 123:926-936. Banks, R.C, C. Cicero, J.L. Dunn, W.W. Kratter, P.C. Rasmussen, J.V. Remsen, Jr., J.D. Rising and D.F. Stotz. 2006. Forty-seventh supplement to the American Ornithologists’ Union check-list of North American birds. Auk 123:926-936. (Link)
Campbell, R.W., N.K. Dawe, I. McTaggart-Cowan, J.M. Cooper, G.W. Kaiser, and M.C.E. McNall. 1990. The Birds of British Columbia, Nonpasserines: Diurnal Birds of Prey Through Woodpeckers. Vol. 2. Royal British Columbia Museum, Victoria, B.C..
Zwickel, F.C., and J.F. Bendell. 2018. Dusky Grouse (Dendragapus obscurus), version 2.1. In: The Birds of North America (P.G. Rodewald, Ed.). Cornell Lab of Ornithology, Ithaca, NY, USA. Zwickel, F.C., and J.F. Bendell. 2018. Dusky Grouse (Dendragapus obscurus), version 2.1. In: The Birds of North America (P.G. Rodewald, Ed.). Cornell Lab of Ornithology, Ithaca, NY, USA. (Link)