Cordilleran Flycatcher
(Empidonax occidentalis)

Overview

Summary

© Jukka Jantunen
For additional photos and vocalizations, visit Dendroica. (Link opens in a new window.)

The "Western" Flycatcher complex was split into Cordilleran and Pacific-slope Flycatchers in 1989 (American Ornithologists' Union 1989). The breeding range of the Cordilleran Flycatcher in Canada remains imperfectly known; thus changes in the Canadian population are difficult to determine. The "Western" Flycatcher expanded its range east and north in British Columbia starting in the mid-1940s (Campbell et al. 1997) with the first record for Alberta in 1954 (Semenchuk 1992). Alberta populations have been assumed to be Cordilleran Flycatchers (Godfrey 1986, Semenchuk 1992, Semenchuk 2007), but recent genetic studies indicate that birds in the Interior of British Columbia and Alberta are intergrades between the two species (Rush et al. 2009).

Designations

Population status

Population estimate

Distribution maps

• BirdLife International / NatureServe
• Breeding Bird Survey (BBS): Relative Abundance and Breeding Distribution (1993-2012)

Migration strategy, occurrence

Responsibility for conservation of world population

Conservation and management

"Western" Flycatchers in Alberta and the British Columbia interior are strongly associated with coniferous forests along creeks, rivers and lakeshores (Campbell et al. 1997, Lowther 2000). The long-term decline in the United States is cause for concern. There have been reports of declines from "cleaning up" by removing downed trees and brush which has resulted in local extirpation (Lowther 2000). Otherwise, causes are not well understood. Further research is necessary to determine the range and status of both Cordilleran and Pacific-slope Flycatchers in Canada.

Bird conservation region strategies

Environment and Climate Change Canada and partners have developed Bird Conservation Region Strategies in each of Canada’s Bird Conservation Regions (BCRs). In these strategies, selected species are identified as priorities for one or more of the following reasons:

• conservation concerns (i.e., species vulnerable due to population size, distribution, population trend, abundance, or threats)
• stewardship responsibilities (i.e., species that typify the regional avifauna or have a large proportion of their range or population in the sub-region)
• management concerns (i.e., species that require ongoing management because of their socio-economic importance as game species, or because of their impacts on other species or habitats)
• other concerns (i.e., species deemed a priority by regional experts for other reasons than those listed above or because they are listed as species at risk or concern at the provincial level)

Select any of the sub-regions below to view the BCR strategy for additional details.

References

• American Ornithologists' Union. 1989. Thirty-seventh supplement to the American Ornithologists' Union check-list of North American birds. Auk 106:532-538. American Ornithologists' Union. 1989. Thirty-seventh supplement to the American Ornithologists' Union check-list of North American birds. Auk 106:532-538. (Link)
• Campbell, R.W., N.K. Dawe, I. McTaggart-Cowan, J.M. Cooper, G.W. Kaiser, M.C.E. McNall, and G.E. J. Smith. 1997. The Birds of British Columbia. Volume 3: Passerines, Flycatchers Through Vireos. UBC Press, Vancouver, BC.
• Godfrey, W. E. 1986. The birds of Canada, revised edition. National Museum of Natural Sciences, Ottawa. 595 pp.
• Lowther, P.E. 2000. Pacific-Slope Flycatcher (Empidonax difficilis) and Cordilleran Flycatcher (Empidonax occidentalis), The Birds of North America Online (A. Poole, Ed.). Cornell Lab of Ornithology, Ithaca, New York. Lowther, P.E. 2000. Pacific-Slope Flycatcher (Empidonax difficilis) and Cordilleran Flycatcher (Empidonax occidentalis), The Birds of North America Online (A. Poole, Ed.). Cornell Lab of Ornithology, Ithaca, New York. (Link)
• Rush, A., R.J. Cannings, and D.E. Irwin. 2009. Analysis of multilocus DNA reveals hybridization in a contact zone between Empidonax flycatchers. Journal of Avian Biology 40: 614-624.
• Semenchuk, G.P. 1992. The Atlas of the Breeding Birds of Alberta. Federation of Alberta Naturalists. Edmonton, Alberta. 391 pp.
• Semenchuk, G.P. 2007. The Atlas of Breeding Birds of Alberta: A Second Look. G.P. Semenchuk, Editor. Federation of Alberta Naturalists. Edmonton, Alberta. 626 pp.