Chapter 5: Greater Sage-Grouse: General Use and Roost Site Occurrence with Pellet Counts as a Measure of Relative Abundance

Greater sage-grouse (Centro- cercus urophasianus) have been declining both spatially and numerically through- out their range because of anthropogenic disturbance and loss and fragmentation of sagebrush (Artemisia spp.) habitats. Un- derstanding how sage-grouse respond to these habitat alterations and disturbanc- es, particularly the types of disturbances and extent at which they respond, is criti- cal to designing management actions and prioritizing areas of conservation. To ad- dress these needs, we developed statisti- cal models of the relationships between occurrence and abundance of greater sage-grouse and multi-scaled measures of vegetation, abiotic, and disturbance in the Wyoming Basins Ecoregional Assess- ment (WBEA) area. Sage-grouse occur- rence was strongly related to the amount of sagebrush within 1 km for both roost site and general use locations. Roost sites were identified by presence of sage-grouse fecal pellet groups whereas general use locations had single pellets. Proximity to anthropogenic disturbance including en- ergy development, power lines, and major roads was negatively associated with sage- grouse occurrence. Models of sage-grouse occurrence correctly predicted active lek locations with >75% accuracy. Our spa- tially explicit models identified areas of high occurrence probability in the WBEA area that can be used to delineate areas for conservation and refine existing conserva- tion plans. These models can also facilitate identification of pathways and corridors important for maintenance of sage-grouse population connectivity.