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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-76 Project area include prairie falcon (Falco mexicanus), osprey (Pandion haliaetus), Swainson’s hawk (Buteo swainsoni), red-tailed hawk (Buteo jamaicensis), American kestrel (Falco sparverius), short-eared owl (Asio flammeus), and great-horned owl (Bubo virginianus). All raptors are protected under the MBTA and are typically sensitive to disturbance while nesting. Nesting sites are vulnerable to construction disturbances because raptors may abandon the nest during periods of high human activity, resulting in egg or nestling mortality and nest failure. Other potential impacts to raptors include collision with the proposed transmission line and habitat loss, including direct habitat loss through vegetation removal and indirect habitat loss or degradation through increased risk of weed invasion and wildfire. Electrocution is not a significant risk to raptors on 230 kV lines because of adequate separation distance between conductors. Implementation of RDFs such as seasonal restrictions and buffers to avoid nesting raptors during construction would limit disturbance to breeding raptors (refer to RDFs in Section 2.3 for a list of nest buffers by species). Implementation of RDFs to minimize collision risk, vegetation disturbance, weed invasion, and wildfires (as described in Sections 4.3.3.1 and 4.3.3.2) would further reduce impacts to raptors. Location-specific occurrences and impact levels are discussed in Section 4.3.4. Waterfowl and Other Aquatic Birds Within the Project area, Waterfowl Priority Species Regional Areas have been identified on four waterbodies within one mile of the proposed Project: the Selah Waterfowl Concentration Area/Selah Gravel Pit Wetlands associated with the Yakima River, located just northwest of the Pomona Heights Substation; the Wanapum Pools Waterfowl Concentration Area within Wanapum Lake on the Columbia River located just northwest of the Vantage Substation; the Priest Rapids Lake Waterfowl Concentration Area on the Columbia River located alongside Route Segment 3b; and the Nunnally Lake Concentration Area on the small lake located just north of Lower Crab Creek along Route Segment 3c. Wanapum Pool and Priest Rapids Lake are also identified by WDFW Priority Habitats and Species (PHS) as regularly occupied by common loons (Gavia immer) in low densities. American white pelicans (Pelecanus erythrorhynchos) have also been documented within the Project study area on the Columbia River. Overall, eight special status aquatic bird species occur or are likely to occur within the Project study area: black-crowned night heron (Nycticorax nycticorax); great blue heron (Ardea herodias); Clark’s, western, and eared grebes (Aechmophorus clarkia, A. occidentalis, and Podiceps nigricollis); tundra swan (Cygnus columbianus); American white pelican; and common loon. Waterfowl and aquatic bird injury and mortality could occur through collision with the transmission line. The only route segments with suitable habitat for waterfowl and other aquatic species are the Columbia River crossings at Route Segments NNR-8 and 3c. In the area of Route Segment NNR-8, the transmission line would parallel four existing transmission lines within 350 to 1,300 feet. To the extent that collision potential exists, the additional transmission line will likely not add greater risk than what already occurs at this crossing. The crossing at Route Segment 3c would not be near any existing transmission lines and may pose a greater collision risk. It is conceivable that waterfowl and other aquatic species occasionally travel across the proposed Project study area en route from the Yakima River to the Columbia River or vice versa and/or between aquatic zones and terrestrial feeding areas such as agricultural fields. The NNR Alternative more or less parallels one or more existing transmission line for its entire route while Alternatives A-H parallel existing transmission lines for a smaller portion of their lengths. RDFs include installing bird flight diverters in locations with known avian mortality through collision with transmission line infrastructure. Aside from collision risk, the scale of biological change and biological disturbance to waterfowl, other aquatic birds, and their habitat is anticipated to be low. Segment-specific impact levels are discussed in Section 4.3.4. Other Special Status Upland Bird Species Priority Species Regional Areas identified by PHS within the Project study area include regular concentration areas for chukar (Alectoris chukar), loggerhead shrike (Lanius ludovicianus), and long- billed curlew (Numenius americanus; a shorebird that breeds in upland grassland or shrub-steppe). Eight other special status upland bird species occur or are likely to occur within the Project study area: ring- necked pheasant (Phasianus colchicus), Vaux’s swift (Chaetura vauxi), gray flycatcher (Empidonax