Using data from the southern and central Sierra Nevada, we evaluated predictions from the California Department of Fish and Game's (CDFG) Wildlife Habitat Relationships (WHR) System for breeding bird species in red fir (Abies magnifica) forests. We counted birds on 34 study sites during the summers of 1983, 1984, and 1985 and detected 50 breeding species. Study sites included stands in each of four structural classes (all four canopy-closure classes within the medium/large-tree size class). Only two bird species that were predicted to occur by the WHR System were not recorded in any of the four sampled structural classes of red fir habitat. However, 26 species were present in at least one class of red fir habitat in which they were not predicted. Based on mean observation frequency and abundance, we subjectively rated the potential ability of each structural class to support low, medium, and high breeding populations of each bird species. Forty-six percent of our predictions were for higher habitat suitability ratings than those in the WHR System. We suggest a historic rating for species that formerly occurred in high numbers, are uncommon or absent today, but may use the habitat again in the future.
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