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4 <br /> bees and flies, visit the flowers (Kaye 1992, Kaye and Kirkland 1994). The species does <br /> not self - pollinate, but depends on these insects for pollen transfer. <br /> Status • <br /> Seventeen distinct populations of Bradshaw's lomatium currently occur in the Willamette <br /> Valley and southwest Washington (Parenti et al. 1993; Gisler 1994; St. Hilare 1994; <br /> Robinson 1995). It is estimated that less than 0.1 percent of the historic populations of <br /> Bradshaw's lomatium remain (Parenti et al. 1993). <br /> V. PROBLEMS FACING THE SPECIES <br /> Rangewide <br /> As described in the final rule to list Bradshaw's lomatium as endangered (53 FR 38451; <br /> September 30, 1988) and Recovery Plan (USFWS 1993), threats to Bradshaw's lomatium <br /> include: (1) loss of habitat; (2) disease; and (3) reproductive strategy of the species <br /> combined, with other stressors such as drought, land management practices, flood <br /> control, fire suppression. <br /> Habitat has been lost by succession, changes in hydrology, and urban or agricultural <br /> development. Willamette Valley wet prairies continue to undergo succession and <br /> invasion by trees and shrubs. This succession was once naturally controlled by <br /> widespread flooding, browsing animals, and fire. Flood control projects in the upper <br /> Willamette basin, urbanization, land use practices, and fire suppression have altered <br /> historic processes that maintained native grasslands. <br /> Flood control and wetland fill and drainage have also affected Bradshaw's lomatium by <br /> reducing available habitat and, possibly, seed dispersal. Surface water reduction <br /> decreased the abundance and distribution of seasonally wet prairies throughout the <br /> Willamette Valley. Since Bradshaw's lomatium is dependent on wet areas, often within <br /> the floodplain of a creek or small river, hydrologic changes have drastically reduced <br /> habitat available to the plant. Bradshaw's lomatium seeds have also been found to have <br /> some buoyancy, and dispersal may be increased by flooding (USFWS 1993). If dispersal <br /> is enhanced by flooding, it is likely that hydrologic changes have reduced dispersal <br /> quantity and distance. <br /> Most habitat for Bradshaw's lomatium occurs in and around Eugene and Corvallis, <br /> Oregon (USFWS 1993). Any undeveloped, flat grasslands which may contain <br /> Bradshaw's lomatium and other native wet prairie species are often prime locations for <br /> urban development. <br /> 97 -00401 <br />