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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-93 anticipated to be effective at minimizing impacts. Following implementation of RDFs, no identifiable impacts are anticipated from Route Segment 2d. Critical habitats for bull trout, the Columbia River Chinook salmon ESU, and the Upper Columbia River steelhead DPS occur within 1.0 mile of Route Segment 2d in the Columbia River. Tributaries of the Columbia River in and near the Project area are not part of the Upper Columbia River Spring Run Chinook salmon ESU; they are part of the Mid-Columbia River Spring Run Chinook salmon ESU which is not listed under the ESA (NOAA 2013). Aside from the Columbia River, it is unlikely that spawning occurs in streams within the Project area. Bull trout and Chinook salmon are not known to spawn within streams within the Project area because the streams are too small and not cold enough over a long enough time period to provide suitable spawning and rearing habitat; however, bull trout could use streams for short periods for foraging (AECOM Environmental 2010). No structure or road construction work would occur directly within the Columbia River. Erosion would be minimized by applying and maintaining standard erosion and sediment control methods. The implementation of RDFs is anticipated to be effective at minimizing impacts to all three species. No identifiable impacts to the three species or their habitats are anticipated to occur through construction, operation, and maintenance of the proposed Project. Breeding loggerhead shrikes were observed within a half mile of Route Segment 2d in 1993. Potential impacts to shrikes include direct habitat loss, indirect habitat loss or degradation, increased predation from corvids and raptors attracted to nesting and/or perching opportunities on the new transmission line structures, and disturbance or displacement from noise or visual disturbance, especially during construction. RDFs would be implemented to minimize impacts, as described in Sections 4.3.3.1 and 4.3.3.2. Impact levels to loggerhead shrike are estimated to be moderate for 2.0 miles of the route segment. White-tailed jackrabbit has been documented within a half mile of Route Segment 2d. Potential impacts include a reduction and degradation of habitat, disturbance and displacement from habitats, increased 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. Impact levels to black-tailed jackrabbits are expected to be moderate for 2.0 miles and low for 5.0 miles. Route Segment 2d crosses 0.9 miles of chukar Priority Species Regional Area. Potential impacts include disturbance or displacement, injury or mortality from vehicle strikes and equipment, and direct habitat loss or degradation. Noise from construction equipment, helicopters, and general construction activities could disturb and displace chukar on a short-term basis. In addition, the transmission line structures would serve as perch sites for raptor species, which could prey on chukar. The implementation of RDFs, as described in Sections 4.3.3.1 and 4.3.3.2, is anticipated to reduce impacts to chukar. Impact levels to chukar are anticipated to be moderate for the 0.9 mile of the route segment that cross the chukar concentration area. Much of the area along the southwest side of the Columbia River has been identified as a mule deer regular large concentration area. This area comes within approximately 0.1 mile of Route Segment 2d for a short stretch of the Project area. Potential impacts to mule deer include habitat loss, habitat degradation from the spread of invasive weeds, collision with vehicles during construction and maintenance and disturbance during construction and maintenance. Mule deer are most likely to be impacted by disturbance during winter when increased energy expenditure may lower survival. Adherence to seasonal restrictions from December 1 to March 1 on construction activities within the designated concentration area should minimize disturbance impacts to mule deer. Because Route Segment 2d does not cross the