Conversion of native sagebrush rangelands for grain and biofuel crop production is a primary agent of land use change in the eastern range of sage-grouse, an icon of the West and ‘candidate' species for possible ESA listing. Staving off grouse declines requires spatial planning tools that target conservation to areas of high biological value at risk of conversion. Past studies are inadequate to guide management because relationships between lek persistence and area of conversion were unknown. Integral to producing robust estimates is the ability to incorporate into analyses impacts of range contraction attributable to conversion before sage-grouse population surveys were established.  We resolve this issue by using logistic regression to model lek type (random vs. extant) as a function of remotely-sensed cropland metrics to capture both the historical and contemporary impacts of tillage on populations.  Results indicate strong negative effects of cropland extent within 6 km of leks. Lek persistence declines by 50% with 24% tillage and by 75% with 36% of land converted. We apply the resulting regression to The Nature Conservancy's new tillage risk map and then rank each of Montana's 13 core areas relative to their biological value and conversion risk. Risk varies by location with east central Montana containing the 3 cores most vulnerable to future tillage. NRCS's Sage Grouse Initiative has ratcheted up by 4x the implementation of sustainable grazing systems to produce more hiding cover for nesting grouse and to help keep ranchers profitable in these high risk cores. Our next step is to run scenarios on future sodbusting risk to identify how to better target voluntary and incentive-based grazing systems and conservation easements that help ‘keep the green side up'.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.