Greater Sage-grouse and the Proposed Withrow Wind Farm

The need for additional energy sources, especially sources that are considered ‘green’, is an important development issue in the state of Washington. As the pressure to expand these developments into remnant areas of native habitat increases, it is important that we consider the potential impacts on our wildlife resources, especially those with large conservation and/or economic ramifications. The following report is designed to provide basic information about what is known and not known about the potential impacts of one of these proposed developments, the Withrow Wind Farm, on greater sage-grouse (Centrocercus urophasianus).

The Withrow Wind Farm is proposed for an area of about 15,000 acres north of the town of Withrow in Douglas County, Washington (Fig. 1). The proposed development of at least 100 turbines is designed to take advantage of moderately elevated topography associated with the terminal moraine of the Okanogan Lobe of the Cordilleran Ice Field.

The proposed project is entirely within the current distribution of greater sage-grouse in Douglas County (Schroeder et al. 2000). The Douglas County population of sage-grouse is the largest of two remaining populations in Washington. Because of the 92% decline of range occupied by sage-grouse in Washington, The Washington Department of Fish and Wildlife listed the greater sage-grouse as a ‘threatened’ species (Hays 1998). Because of regional declines of sage-grouse, the U.S. Fish and Wildlife Service federally classified the sage-grouse in Washington and northern Oregon as a ‘distinct population segment’ that warranted listing as a threatened or endangered species. However, in this case the listing decision was precluded by higher listing priorities (U.S. Fish and Wildlife Service 2001).

The Washington Department of Fish and Wildlife produced a management plan for sage-grouse in 1995. This management plan was followed up with a recovery plan (Stinson et al. 2004). The recovery plan addresses the potential impacts of wind power on sage-grouse in Washington in a general sense. In addition the Washington Department of Fish and Wildlife (2003) has published guidelines for wind project developments. Guidelines have also been recommended for wind power developments by the Wildlife Management Institute (Manes et al. 2002) and the U.S. Fish and Wildlife Service (2003). Cumulatively, these recommendations are often based on ‘educated guesses’ based on research on surrogate species (i.e., other species of prairie grouse) or on surrogate developments (i.e., roads and power lines). In general, there is a lack of published data on wind power development within the occupied range of sage-grouse in North America (Schroeder et al. 2004). This is due to a lack of wind development in ‘prime’ sage-grouse habitat and/or a lack of data to evaluate the potential effects.