Bird associations with floristics and physiognomy differ across five biogeographic subregions of the Great Basin, USA.

This article investigates how associations between bird occupancy and vegetation—specifically plant species composition (floristics) and vegetation structure (physiognomy)—vary across five biogeographic subregions of the Great Basin, USA (central, western, Sierra Nevada, northern, and eastern). Using point-count surveys of 19 bird species and vegetation measurements, the study found that bird-plant associations differ substantially among subregions, with no species showing consistent associations with the same plant species or functional group across all subregions. Notably, 24% of bird-plant associations significant at the entire Great Basin scale were not significant within any subregion, and differences were most pronounced between the Sierra Nevada and central or western subregions. The findings suggest that regional bird management plans should account for geographic variation in bird-vegetation relationships rather than assuming uniform habitat associations across the Great Basin.