We reviewed the historic and present distribution of Greater Sage-Grouse (Centrocercus urophasianus) in Canada and found that the species has been eliminated from approximately 90% of its estimated historic distribution. Sage-grouse have been extirpated from British Columbia and reduced to remnant populations in Alberta and Saskatchewan. Estimates of the size of the population decline in Canada range from 66 to 92% over the last 30 years based on currently occupied habitat. The number of active lek sites has continued to decline, suggesting that some habitats have become unsuitable to support viable sage-grouse populations. Number of yearling males recruiting to leks each spring has been low, suggesting that production and overwinter survival of young are the major problems related to the decline. Low chick survival rate, with only 18% surviving to 50 days of age, is the most likely parameter contributing to the population decline.
Source:
Aldridge, Cameron L., and R. Mark Brigham. 2003 Distribution, abundance, and status of the Greater Sage-Grouse,
Centrocercus urophasianus, in Canada. Canadian Field-Naturalist 117(1): 25–34.
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