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The effects of management practices on grassland birds—Brewer’s Sparrow ( Spizella breweri breweri )

Brett L. Walker·Lawrence D. Igl·Jill A. Shaffer
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Abstract

Keys to Brewer’s Sparrow ( Spizella breweri breweri ) management include maintaining extensive, unfragmented patches of suitable breeding habitat; reducing conifer cover and height; preventing the invasion of conifers and nonnative plants, especially cheatgrass (downy brome [ Bromus tectorum ]); minimizing disturbance to soil; and restricting the use of pesticides and herbicides during the breeding season (April–July). Brewer’s Sparrows have been reported to use breeding habitats with 12–170 centimeter (cm) vegetation height, 2–34 cm visual obstruction reading, 1–74 percent grass cover, less than (<) 19 percent forb cover, 1–65 percent shrub cover, 1–75 percent bare ground, 2–61 percent litter cover, and <1 cm litter depth. During post-fledging dispersal in July, Brewer’s Sparrow adults and young may shift habitat use to nearby aspen ( Populus species [spp.]), riparian shrub, or deciduous mountain shrub habitats, so these habitats also may be important for management.

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Brett L. Walker, Lawrence D. Igl, Jill A. Shaffer. 2020-10-06. The effects of management practices on grassland birds—Brewer’s Sparrow ( Spizella breweri breweri ). https://doi.org/10.3133/pp1842aa

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