|Abstract or Summary
- The United States Fish and Wildlife Service currently uses fire as a management tool to improve Greater Sage Grouse (Centrocercus urophasianus Bonaparte) nesting and brood-rearing habitat at Hart Mountain National Antelope Refuge (HMNAR) in S.E. Oregon. Previous studies at HMNAR revealed use of burned areas by sage grouse throughout the breeding season, but quantitative
evaluation of breeding-season habitat use in relation to burned areas was unavailable. Further, the effects of prescribed fire and wildfire on sage-grouse habitat use and habitat selection are poorly understood and controversial. I evaluated a comprehensive database of all prescribed fire and wildfire data (1947-2000) and sage-grouse breeding-season habitat data (1989-2000) as a means to evaluate and quantify the temporal and spatial effects of habitat use by female sagegrouse relative to burned areas. Nesting, brood-rearing, and broodless females generally avoided 89%, 89%, and 77%, respectively, of available burned habitats; unburned habitats were typically used. All 5 nests in burns < 20 years old were unsuccessful, but nesting success in >20 year-old burns (29%, n = 6/21) and unburned areas (28%, n = 49/177) was similar. When burned habitats were used, they were typically mid- to late-successional mountain big sagebrush burns. Age of burn, and the resultant return of the shrub (i.e., sagebrush) component, was most commonly associated with use of burned areas by nesting and brood-rearing females. Fire in areas with higher biotic potential (in terms of soil productivity/structure, floral diversity, and precipitation), such as mountain big sagebrush [A. t. Nutt. var. vaseyana (Rybd.) Beetle] cover types where the shrub, herbaceous, and invertebrate components have returned, may provide favorable habitat for limited nesting, brood-rearing, and broodless female use. However, in areas with generally lower biotic potential, such as low sagebrush (A. arbuscula Nutt.) and Wyoming big sagebrush (A. tridentata Nutt. var. wyomingensis Beetle & Young) cover types, fire seemingly provided no apparent value in terms of nesting,
brood-rearing, and broodless female use. Although future research may further elucidate burned habitat use trends, managers should be cautious in the use of prescribed fire in sage grouse habitats.