Bird–Habitat Relationships in Interior Columbia Basin Shrubsteppe

Abstract

Abstract. Vegetation structure is important in structuring avian communities. In the sagebrush biome, where continued habitat loss is thought to threaten shrusteppe-obligate birds, both remotely sensed and field-acquired measures of big sagebrush (Artemisia tridentata) cover have proven valuable in understanding avian abundance. Differences in structure between the exotic annual cheatgrass (Bromus tectorum) and native bunchgrasses are also expected to be important. We used abundance from 318 point-count locations, coupled with field vegetation measurements and a detailed vegetation map, to model abundance of four shrub- and four grassland-associated avian species in southeastern Washington. Specifically, we ask whether species' abundances in bunchgrass and cheatgrass differ and whether mapped categories of cover adequately explain species' abundances or whether finegrained, field-measured differences in vegetation are also important in explaining abundance. We found that the abundance of shrub associates ...