Great Basin Naturalist


Nest sites selected by Sage Thrashers (Oreoscoptes montanus) in southeastern Idaho were characterized and compared with available habitat. Microhabitats within 5 m of nests had taller and more aggregated shrubs and less bare ground than the study area in general. Big sagebrush (Artemisia tridentata wyomingensis) plants used for nesting were taller than average available shrubs, had greater foliage density, were more often living, and more frequently had branches and foliage within 30 cm of the ground. Nest placement was specific with respect to relative nest height and distance from the top and perimeter of the support shrub. Sage Thrashers disproportionately used easterly exposures and underused westerly exposures for their nests.