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Vantage to Pomona Heights Chapter 3 230 kV Transmission Line Project FEIS Affected Environment PAGE 3-60 including the MR Subroute ROW was conducted in 2013 using a combination of remote sensing data and field data collected during vegetation surveys and Sage-Grouse walking transect surveys. Detailed methods and results of both habitat assessments are included in Appendix B-2 (Sage-Grouse Habitat Assessments). Generally speaking, the highest concentrations of suitable habitat occurs along the south edge of JBLM YTC in Route Segment 2b and near Badger Pocket in Route Segments NNR-4, NNR-5, and the western end of NNR-6 with other concentrations of suitable habitat in NNR-7 and the north half of Route Segment 3c. The relatively disturbed, weedy southwestern portions of the Project study area (Route Segments 1a/NNR-1, 1b, 1c, 2a, 2c, and NNR-2) contain less suitable habitat. Sage-Grouse habitat crossed is discussed for each route segment in Section 4.3.4, and specific habitat delineations are described in Appendix B-2 – Sage-Grouse Habitat Assessment. While a detailed, fine-scale habitat assessment was conducted within the NNR Alternative ROW, it was not feasible to use the same fine-scale methodology for the entire eight-mile-wide Sage-Grouse analysis area. To estimate habitat suitability within the analysis area, land cover data were used. A composite of USGS GAP data, JBLM YTC vegetation data, and vegetation data collected during POWER Engineers Inc.’s (POWER) field surveys that were completed in support of the DEIS and SDEIS were used to delineate 12 categories of land cover type. Each of these was in turn assigned a Sage-Grouse habitat suitability value of suitable, marginal, or unsuitable. The values were assigned as follows: 1) suitable habitat includes “sagebrush/perennial grassland;” 2) marginal habitat includes “sagebrush/annual grassland,” “riparian,” “intermittent stream,” and “bitterbrush/perennial grassland;” and 3) unsuitable habitat includes “forb,” “perennial grassland,” “rabbitbrush/annual grassland,” “annual grassland and noxious weeds,” “basalt cliffs/rock,” “trees,” and “other” (includes agriculture, developed/disturbed areas, and open water). Overall, approximately 48 percent of the eight-mile wide Sage-Grouse analysis area was classified as suitable habitat, three percent as marginal, and 49 percent as unsuitable (see Table 3.3-9). It should be noted that this is only a coarse-scale approximation of true habitat suitability for Sage-Grouse, which is ultimately dependent on the condition of the vegetation community. In addition to the appropriate species composition within the vegetation community, an assessment of habitat conditions includes structural components such as canopy cover and height that provide additional information on the quality and habitat suitability for Sage-Grouse. For example, within the habitat classified as “sagebrush/perennial grassland” (and, therefore, considered as suitable Sage-Grouse habitat) some areas are likely to have insufficient sagebrush cover to provide truly suitable habitat. Habitat Connectivity Maintenance and restoration of habitat connectivity have important implications for the genetic and demographic health of wildlife populations. Anthropogenic features and land uses can reduce connectivity by fragmenting habitat and hindering the movement of wildlife. Fragmented landscapes with reduced connectivity support fewer animals and isolated local populations face higher local extinction rates and lower likelihood of recolonization as well as loss of genetic diversity (Beissinger and McCullough 2002). Development and agriculture have fragmented sagebrush-steppe within Washington and habitat connectivity is degraded and threatened for Sage-Grouse (Washington Wildlife Habitat Connectivity Working Group [WHCWG] 2010). The YTC Sage-Grouse population is isolated from the Mansfield Plateau/Moses Coulee population by more than 30 miles and from populations in Oregon and Idaho by about 150 miles (Robb and Schroeder 2012). These two populations have reduced genetic diversity relative to populations outside of Washington, and differ genetically from each other suggesting a recent genetic bottleneck and little gene- flow between these populations (Benedict et al. 2003; Oyler-McCance et al. 2005). Sage-Grouse exhibit two types of long-distance movements: 1) natal dispersal (movement a juvenile makes from its natal home range to its adult home range) and 2) seasonal migrations. Minimal existing dispersal information indicates average natal dispersal distances for juvenile Sage-Grouse is