LC
Dusky Grouse Dendragapus obscurus



Justification

Justification of Red List Category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Population justification
(Rich et al. 2004)

Trend justification
This species has undergone a small or statistically insignificant decrease over the last 40 years in North America (data for Dendropagus obscurus and D. fuliginosus combined, from Breeding Bird Survey and/or Christmas Bird Count: Butcher and Niven 2007).

Distribution and population

This species has a large range, which spreads from northern Canada to California across the internal western United States and Canada.

Ecology

The species occurs in a variety of pine and fir forest habitats from sea level to 3,600 m close to the tree line.

Acknowledgements

Text account compilers
Butchart, S., Bird, J.


Recommended citation
BirdLife International (2019) Species factsheet: Dendragapus obscurus. Downloaded from http://www.birdlife.org on 21/03/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/03/2019.