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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-73 populations and two reintroduced populations). Additional information on this analysis is provided in Appendix B-2. Sage-Grouse-specific WHCWG analyses identified four Habitat Concentration Areas (HCA) within Washington. These include the YTC and Mansfield Plateau/Moses Coulee populations already mentioned and two reintroduced populations, one in the northern Crab Creek drainage in Lincoln County and one on the Yakama Indian Reservation in Yakima County. Sage-Grouse were translocated to the Yakama Indian Reservation in 2006, but, as of 2012, there were no confirmed observations of breeding activity (Robb and Schroeder 2012). The WHCWG analysis identified the linkage between the YTC HCA and the Mansfield Plateau/Moses Coulee HCA as “fairly good” (Figure 3.3-3). Much of the habitat along this linkage zone is shrub-steppe that is protected within state-owned wildlife areas (e.g., WDFW Colockum Wildlife Area). Impediments to this linkage include the relative steepness of the terrain and disturbance associated with Interstate (I) 90, several existing transmission lines, and two wind energy developments. Conditions for movement are best in the central portion of the linkage, but there are areas of concern at both ends. Near its northern end, the modeled linkage zone is constricted as it crosses the Columbia River near Rock Island Dam. Near the southern end, north of I-90 and the NNR Alternative, the linkage is constricted by wind energy developments on private and state land (including both WDFW-managed land and Washington Department of Natural Resources state trust land; Robb and Schroeder 2012). The least-cost pathway of the linkage zone appears to intersect the NNR Alternative near Route Segments NNR-6 and NNR-7. Local patterns of Sage-Grouse distribution suggest that Route Segment NNR-6 is likely to be the most important connectivity zone. Telemetry data, observational data, and population range modeling indicates a higher probability of Sage-Grouse use near Route Segments NNR-4, NNR-5 and western Route Segment NNR-6 than near eastern Route Segment NNR-6 and Route Segment NNR-7, but the presence of the two existing wind developments north of I-90 reduces the linkage value of the more western segments, according to the WHCWG model. Nevertheless, it appears that the entire stretch between Badger Pocket and the Columbia River could serve as valuable linkage habitat. Route Segment NNR-7 is separated from the existing population range by the steep terrain of the Saddle Mountains. On JBLM YTC, Sage-Grouse prefer flatter areas (less than 15 percent slope; Livingston 1998). WHCWG did not include slope in their models, asserting that slope is not likely a factor impeding movement (Robb and Schroeder 2012). According to Robb and Schroeder (2012), there is no direct linkage between the YTC HCA and the Upper Crab Creek HCA, but the two connect via the Mansfield Plateau/Moses Coulee HCA. Thus there is no identified Sage-Grouse connectivity habitat in or near the east side of the proposed Project (Route Segments 3a, 3b, and 3c). Of the three main Sage-Grouse connectivity zones identified by WHCWG, the one linking the YTC population with the reintroduced Yakama Indian Reservation population was the weakest. That connectivity zone would cross Alternatives A-H, with the most valuable zone crossing Route Segments 2b and 2c, before detouring around far to the west (or to the east) in order to connect with the habitat on the Yakama Indian Reservation. But, according to Robb and Schroeder (2012), development along the I- 82 corridor “essentially isolates” habitat on the Yakama Indian Reservation from the YTC population, and potential for movement between the two areas “looks dismal.” None of the proposed route segments are likely to impact Sage-Grouse connectivity to the south; given the existing barriers, it is unlikely that movement would occur between the YTC and Yakama Indian Reservation populations with or without development of any of the Action Alternatives.