For mid-story and canopy-nesting birds, the geographic pattern of species richness is very similar to that shown by woodland birds. The numbers of species are largest from the northeastern U.S. across the Great Lakes into central Canada. However, the regions with relatively few species are more extensive in the Great Basin and along the western Great Plains, and also include portions of southern Texas and the Florida peninsula.
In eastern North America, positive trends prevail from the Great Lakes and New England south into the Carolinas. Positive trends also occur in the Great Basin and Rocky Mountain regions of western North America, and extend into the northern Great Plains of the U.S. Declines predominate from California and Nevada north into southern British Columbia, and in the southeastern states from Oklahoma, Arkansas, and southern Kansas to the Florida peninsula.
Since this group of birds is restricted to woodland habitats, its percentage of increasing species (54%) is very similar to that for the woodland bird group (56%). Not surprisingly, the geographic patterns in trends and species richness are very similar for both groups.