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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-117 sagebrush/perennial grassland (Table 4.3-4). Areas classified as annual grassland and noxious weeds would experience 12.8 acres of long-term disturbance and 18.6 acres of short-term disturbance. Agriculture/disturbed areas would experience 8.6 acres of long-term and 9.9 acres of short-term disturbance. RDFs would be implemented to minimize habitat loss and degradation, as described in Section 4.3.3.1. Impact levels to habitat are expected to be low for 7.5 miles and moderate for 4.4 miles (sagebrush/perennial grassland). The presence of new transmission line structures, which could provide additional perch and/or nesting sites for avian predators, could negatively impact nearby prey species such as small mammals and avian species, particularly when the new structures are built in an area where perching opportunities currently do not exist (i.e., greater than 0.25 mile from existing structures or trees). Construction of Route Segment MR-1 would require an estimated 90 structures in a landscape dominated by low growing grasses and shrubs. Approximately 85 of the new structures would be located greater than 0.25 mile from an existing transmission line. Route Segment MR-1 was proposed as an option to Route Segment NNR-4o/NNR4u. Compared with Route Segment NNR-4o/NNR-4u, Route Segment MR-1 would require 55 more new structures (Table 4.3-5). Within 1.0 mile of Route Segment MR-1 potentially suitable habitat is present for 43 special status wildlife species that are possible, likely, or known to occur (Tables 3.3-2, 3.3-3, and 3.3-7). Potential impacts and RDFs to address them are discussed in Sections 4.3.3.1 and 4.3.3.2. Species or wildlife resources that have been documented at specific locations within one mile of Route Segment MR-1 include a cliff band with a high concentration of nesting raptors, several golden eagle nests within one breeding territory, a historic ferruginous hawk nest (but sensitive to nest disturbance), white-tailed jackrabbit, and winter range for bighorn sheep. Cliff bands occur along Lmuma Creek, within 1.0 mile of Route Segment MR-1; the cliffs attract high concentrations of raptors, including prairie falcons (not a special status species, but sensitive to nest disturbance) and several golden eagle nests associated with one breeding territory, approximately 0.6 mile from the route segment. A historic ferruginous hawk nest was documented in 1994 on top of a six-foot rock outcrop approximately 0.9 mile from the route segment. Cliffs would be spanned thus avoiding direct disturbance to the habitat. Within the breeding season, construction would be avoided within species-specific active raptor nest buffers to avoid disturbing nesting birds (0.5 mile for golden eagle and ferruginous hawk and 0.25 mile for prairie falcon; see RDFs in Chapter 2). Impact levels on golden eagles are anticipated to be moderate for 1.2 miles and impact levels on ferruginous hawks are expected to be moderate for 0.2 mile. White-tailed jackrabbit has been documented approximately 0.8 mile from Route Segment MR-1. Potential impacts include a reduction and degradation of habitat, disturbance and displacement from habitats, increase in predation from avian predators, increased human activity, introduction and spread of noxious weeds, and injury or mortality due to collision with construction equipment. RDFs to address the impacts are described in Sections 4.3.3.1 and 4.3.3.2. No identifiable impacts are anticipated to occur to mule deer through construction, operation, and maintenance of the proposed Project. Bighorn sheep winter range occurs within one mile of Route Segment MR-1 and is crossed by the proposed route segment for 0.7 mile on the steep slopes surrounding the Yakima River Canyon and Lmuma Creek and its tributaries. Potential impacts to bighorn sheep include direct habitat loss, habitat degradation through weed spread and/or changes in fire regime, collision with vehicles during construction and maintenance, and disturbance during construction and maintenance. Adherence to seasonal restrictions on construction activities within designated winter range should minimize disturbance impacts to bighorn sheep. Additional RDFs to minimize disturbance impacts and collision risk are described in Section 4.3.3.2; RDFs to minimize habitat loss and degradation are described in