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* * DRAFT ** 4 V. PROBLEMS FACING THE SPECIES Rangewide As described in the final rule to list Bradshaw's lomatium as endangered (53 FR 38451; September 30, 1988) and the Recovery Plan (USFWS 1993), threats to Bradshaw's lomatium include: (1) loss of habitat; (2) disease; and (3) reproductive strategy of the species combined with other stressors such as drought, land management practices, flood control, fire suppression. (1) The present or threatened destruction, modification, or curtailment of the species' habitat or range. Habitat has been lost by succession, changes in hydrology, and urban or agricultural development. Willamette Valley wet prairies continue to undergo succession and invasion by trees and shrubs. This succession was once naturally controlled by widespread flooding, browsing animals, and fire. Flood control projects, urbanization, land use practices, and fire suppression have altered the historic processes that maintained native grasslands. Flood control and wetland fill and drainage have also affected Bradshaw's lomatium by reducing available habitat and, possibly, seed dispersal. Surface water reduction resulting from flood control decreased the abundance and distribution of seasonally wet prairies throughout the Willamette Valley. Since Bradshaw's lomatium is dependent on wet areas, often within the floodplain of a creek or small river (e.g., Amazon Creek), hydrologic changes in the Willamette Valley have drastically reduced habitat available to the plant. Bradshaw's lomatium seeds have also been found to have some buoyancy, and dispersal may be increased by flooding ( USFWS 1993). It is likely that human - caused changes in the flood regime with the Willamette Valley have reduced dispersal quantity and distance. Most of the habitat for Bradshaw's lomatium occurs in and around Eugene and Corvallis, Oregon ( USFWS 1993). Any undeveloped, flat grasslands which may contain Bradshaw's lomatium and other native wet prairie species are often primary targets for urban development. Bradshaw's lomatium occurs in wetlands, often on private lands which may be developed with the issuance of dredge /fill permits from the Corps of Engineers and the Division of State Lands. (2) Disease or predation. Disease may be affecting Bradshaw's lomatium, particularly the smaller populations. A fungus that causes brown spot disease occurs sporadically within a population, destroying the aboveground portions of the plants. Aphids and spittle bugs also parasitize Bradshaw's lomatium. These parasites were found exclusively on plants with seeds