Grazing - Northern Shrub steppe Density index One bird census On shrub steppe, Kantrud and Plains (pairs/min x 103) per 65 ha plot decreasing density Kologiski 1983 using hollow as grazing square technique pressure increases, but still more abundant than most species. Pattern not consistent in other subregions. Grazing - Northern CO Shortgrass Breeding bird pairs Literature review No breeding pairs Ryder 1980 (Central Plains prairie per 20 acres on summer-grazed Experimental plots. Some pairs Range) on winter-grazed, but fewer on heavily grazed plots compared to lightly grazed plots. Grazing NC Eastern ID Big sagebrush Successful nests Visual observation Effects of grazing Reynolds and Trost (sheep) and former in 4-ha grid. inconclusive; 1980 sagebrush crested range reseeded wheatgrass with crested occurrence the wheatgrass driving factor. Grazing NC Great Basin Various habitat Bird abundance One-mile Major decrease in Page et al. 1978 (CA/NV) types including census low sagebrush; low sagebrush inconclusive in and big big sagebrush sagebrush habitats. Prefer low grass, not bare ground? Grazing - Central Plains Shortgrass Number observed Plot counts, Brewer’s Giezentanner 1970 Experimental prairie roadside counts, Sparrows Range, northern nest searches, restricted almost CO territory entirely to winter determinations, and use pastures that specimen contained collections. fourwing saltbush.
Grazing - Northern Plains Shrub steppe Density index (pairs/min x 103) One bird census per 65 ha plot using hollow square technique On shrub steppe, decreasing density as grazing pressure increases, but still more abundant than most species. Pattern not consistent in other subregions. Kantrud and Kologiski 1983 Grazing - Northern CO (Central Plains Experimental Range) Shortgrass prairie Breeding bird pairs per 20 acres Literature review No breeding pairs on summer-grazed plots. Some pairs on winter-grazed, but fewer on heavily grazed plots compared to lightly grazed plots. Ryder 1980 Grazing (sheep) NC Eastern ID Big sagebrush and former sagebrush range reseeded with crested wheatgrass Successful nests Visual observation in 4-ha grid. Effects of grazing inconclusive; crested wheatgrass occurrence the driving factor. Reynolds and Trost 1980 Grazing NC Great Basin (CA/NV) Various habitat types including low sagebrush and big sagebrush Bird abundance One-mile census Major decrease in low sagebrush; inconclusive in big sagebrush habitats. Prefer low grass, not bare ground? Page et al. 1978 Grazing - Central Plains Experimental Range, northern CO Shortgrass prairie Number observed Plot counts, roadside counts, nest searches, territory determinations, and specimen collections. Brewer’s Sparrows restricted almost entirely to winter use pastures that contained fourwing saltbush. Giezentanner 1970
Sagebrush%20birds%20WAFWA%20draft%2010-27-16.docx