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Based on field surveys and review of available data, habitat in the Action Area and adjacent areas was characterized in general terms and in terms of its ability to support special-status species. 3.4.3.1 Fish In this reach of the river, aquatic habitat is characterized by a constrained channel (often between riprapped flood control levees) with a sand/mud bottom, little if any submerged aquatic or emergent vegetation, and intermittent adjacent riparian trees. The channel is routinely subject to scouring flows. Below mean high water, the river bank consists of a riprapped section with about 3-6 feet (0.9 to 1.8 meters) of unvegetated earthen bank leading to the edge of the berm at the base of the sloped portion of the levee. Riprapped sections provide cover for non-native predatory fish such as striped bass, largemouth and smallmouth bass. Review of the available fisheries data indicates that the following special-status species would be in the Action Area for at least some part of the construction period: Winter-run Chinook (Oncorhynchus tshawytscha) (CE/FE) Spring-run Chinook salmon (Oncorhynchus tshawytscha) (CT/FT) Fall-run/late-fall-run Chinook salmon (Oncorhynchus tshawytscha) Essential Fish Habitat for Chinook salmon Steelhead (Oncorhynchus mykiss) (FT) Green sturgeon (Acipenser medirostris) River lamprey (Lampetra ayresi) Pacific lamprey (Lampetra tridentata) Hardhead (Mylopharcodon concephalus) Sacramento splittail (Pogonichthys macrolepidotus) California roach (Hesperoleucus symmetricus) The Action Area is also within critical habitat for winter-run Chinook salmon and proposed critical habitat for spring-run Chinook salmon and Central Valley steelhead. In addition, a suite of non-native species may utilize the Action Area, including largemouth bass, smallmouth bass, and inland silversides. 3.4.3.2 Raptors The levees of the Sacramento River in this reach are intermittently vegetated with a thin band of riparian vegetation dominated by Fremont's cottonwood (Populus fremontii, ssp fremonti), willow (Salix spp.), and valley oak (Quercus lobata). Some portions of this mature riparian habitat are considered suitable for raptor nesting. In 2001 and 2005 surveys, raptor nests (great horned owl, red-tailed hawk, and Swainson's hawk) were found in levee riparian areas between Boyers Bend Pumping Plant and the proposed Combined Pumping Plant/Fish Screen site, or about 2500-3000 feet (750-900 meters) from either site. The nests were in mature valley oaks or cottonwoods along the levee. An additional active Swainson's hawk nest was confirmed at Poker Bend, about 2,000 feet (600 meters) north of the Tyndall Mound Pumping Plant. During 2001, only one of the Swainson's hawk nests successfully fledged young. Pairs of Swainson's hawks exhibiting nesting behavior were also observed near Millers Landing and Boyer's Landing, but successful nesting was not confirmed. On March 30, 2005, four pairs of Swainson's hawks were observed and vocalizing in this same area. Additional Swainson's hawk nesting surveys will be conducted throughout the 2005 nesting season to provide comparative data for the 2001 and 2005 nesting seasons. Several northern harriers were observed foraging in adjacent agricultural fields during 2001 and 2005 surveys, but shrubby vegetation suitable for nesting is limited to narrow stretches along the riverside of the levees. No active nests have been recorded in the area. . 3.4.3.3 Nesting Resident and Migratory Songbirds Passerine species such as tree swallow, western scrub-jay, house wren, northern flicker, and California towhee were observed to nest in the riparian corridor and in isolated trees and shrubs along the levee portion of the Action Area. In addition, cliff-swallows (Hirundo pyrrhonata) nest under the Tyndall Mound and Boyers Bend pumping plants. 3.4.3.4 Upland, Ground-nesting, and Aquatic species In or adjacent to the construction right-of-way for the combined screen, the new and modified canals, the borrow site, and the existing pumping facilities to be decommissioned and removed, upland habitats consist mainly of non-native, ruderal species. There is no riparian vegetation along any of the canals to be modified or along alignments for new canals. A majority of the lands proposed for construction of facilities are actively farmed or routinely disturbed by operation and maintenance activities. Although several plant special-status species have been previously been recorded on the CNDDB in the general vicinity of the project Action Area (Heckard's pepper grass (Lepidium latipes var.heckardii) and rose-mallow (Hibiscus lasiocarpus)) no special status plants were found during the various field surveys of the Action Area. There is no suitable resident habitat for giant garter snakes or northwestern pond turtles in the RD108 system of concrete-lined irrigation canals or along the currently-farmed alignment of proposed new canal segments in the northern portion of the Action Area where crops consist of wheat and alfalfa. The canals and drains are characterized by variable flow velocity, and the lack of emergent herbaceous vegetation. There are no upland refugia or adjacent grassy upland habitat which are identified in the Recovery Plan for the Giant Garter Snake as necessary elements of giant garter snake habitat. The lined canals also do not have appropriate substrate for the species. There is suitable aquatic/emergent habitat for these species in and along the existing Main Drain canal, which is near the prospective borrow sites. Giant garter snake use of lined and/or routinely maintained canals would thus be incidental and probably confined to use for transit between populations. Rice fields in other portions of the project area may provide suitable habitat for giant garter snakes during the active season. However, there is no connectivity between these areas, known giant garter snake habitat, and the Action Area. Burrowing owls, which often occupy abandoned ground squirrel (Spermophilus beecheyi) burrows in levee embankments, along fence lines, and along road berms, were not recorded during 2001 or 2005 field surveys and may be excluded from this potential habitat by ongoing management of levees and canal embankments. State Highway 45 is the main general access road for construction-related traffic. In the vicinity of the project, it is a two-lane road through actively farmed fields. Although the shoulder is a weedy, disturbed ruderal habitat, it is isolated from areas of suitable wildlife habitat by adjacent plowed fields. The road shoulder is subject to routine disturbance during plowing and harvesting of adjacent fields. There are California ground squirrels and other common rodents in these fields and in the shoulder habitat, but no suitable habitat for special-status invertebrates, reptiles, amphibians, or mammals exists along this arterial. Local access to the various construction sites will be via existing agricultural roads and the maintenance road/easement along existing canals. These dirt roads through agricultural fields are generally plowed and planted annually to the edge of the road. Wildlife habitat is restricted to narrow corridors along portions of interior ditches that have not been mowed, burned, or treated with herbicides. 3.4.3.5 Valley Elderberry Longhorn Beetle This species is known to occur in the general project area, and clumps of suitable valley elderberry shrubs were found at the following locations along the Sacramento River near the project area:
These elderberries all contain stems with diameters greater than one inch at ground level, but are not located within the construction footprint or in an area where they might be affected by construction traffic. Based on these findings, a number of special-status species that generally occur in the Kirkville 7.5 minute quadrangle are not addressed in this EA/Initial Study because (a) they are not known to occur in the Action Area, (b) there is no suitable habitat for them in the Action Area, and/or (c) there is no mechanism by which they would be affected by the project (Table 3-2). The basis for these conclusions and the rationale for excluding them from consideration in this EA/Initial Study are listed on Table 3-2. Table 3-2. Species excluded from detailed analysis in this EA/Initial Study.
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