2004-01-29_REVISION - M1987113 (2)

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Final OU 11 Combined Phases RFI/RI As with the vegetation, surveys were conducted to document relative abundance and diversity of wildlife at OU 11 in sprayed, non-sprayed, and reference aeeas to identify any impacts. Small mammals were trapped, and large mammals and birds were observed and recorded. Results of these surveys documented no differences between transectlocations associated with the spray versus non-spray and reference areas in the relative abundance survey. Breeding bird results suggest higher bird densities at the WSF than at reference areas. The WSF had the highest population of grasshopper sparrows of any location sampled at RFETS. These birds prefer higher stratum grass habitats than other species, and this habitat is common at OU 11. The small mammal capture data were inconclusive due to low numbers of captures in the reference site, the spray areas, and the non-spray areas at OU 11. It is likely that the low numbers of captures were due to the absence of burrowing sites in the upland soils at the WSF. This data is presented and discussed in more detail in the OU 11 FSP TM (EG&G, 1994a). Overall, the ecological data collected revealed no evidence of adverse biotic effects between the sprayed, non-sprayed, and reference areas investigated at OU 11. 3.7.3 Sensitive Habitats and Endangered Species A recent report identified four plant species of special concern potentially present at RFETS (EG&G, 1995d). Three of the species have not been identified at RFETS, but the appropriate habitats for the species do exist. All four of the species require habitats that do not exist at OU 11. Plants include one federally listed threatened species, Ute lady's tresses; one Category 2 species, Colorado butterfly plant; and two species of concern in Colorado, fork[ip three-awn and toothcup. Ute lady's tresses have been reported a few miles south of the site, and the habitat exists at the site; however, a 1992 survey identified no occurrences at RFETS. Colorado butterfly plant has not been reported a[ or near the site, but the suitable wetlands habitat does exist at RFETS though not at OU 11. Forktip three-awn was reported along Woman Creek in 1973 and was documented in the same area in 1992. OU 11 does not contain suitable habitat for this plant. Toothcup has been reported in a temporary pool east of Boulder, Colorado, but not at RFETS or OU 11. Three federally listed endangered wildlife species potentially exist at RFETS but are extremely unlikely inhabitants of OU 11: black-footed ferret, peregrine falcon, and bald eagle. Black-footed ferrets require habitat in and around prairie dog colonies. Neither prairie dog colonies nor black-footed ferrets are known to exist at OU 11. Peregrine falcons may be periodic migrants in the area, but the closest reported nest was ]0 km northwest of RFETS in 1991. Though bald eagles have been seen during the winter months at RFETS, no roost areas at RFETS have been located. A lack of trees and tp\25090721sec3.doc 3-26 F/A/95