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01,/20/95 10:47 1:11 231 6195 PTLD. FIFLD STA. [0005 <br /> . • Wetland. Plan (City. of Eugene 1992.) to' categorize.•deve_ lopable ands protected <br /> areas in • the West Eugene_ area,• but: _this. ,plan has not been. submitted : for.. <br /> consultation under the Act. The impact of development in the Eugene area on <br /> . L. bradshawii has not been ianalyted. . : - <br /> • Outside urban areas, habitat is threatened by agricultural: and- residential . . <br /> development. Agricultural development not only directly destroys habitat; - but. <br /> activities associated with 'agriculture also affect L. bradshawii and its ' <br /> . habitat. Overspray: and leaching of herbicides, grazing, and the introduction <br /> of non - native' plants can kill plants or degrade :suitable habitat.' In <br /> addition; hydrologic associated with irrigation and flood control in <br /> agricultural areas have reduced available habitat. <br /> In addition to habitat: alterations, disease•may also be impacting L. <br /> bradshawii, particularly'the :smaller populations. A fungus which causes a . <br /> brown spot disease occurs sporadically within a population,' destroying the. :•• <br /> above - ground portions. of the plants. Aphids and: spittle: bugs' also, parasitize <br /> L.•bradshawii. These. parasites were found exclusively on plants with seeds <br /> (Kagan 1980): The seed on fungus- infected plants seldom reached maturity <br /> before the plant died back. Parasitized plants had a significantly.higher <br /> incidence of•aborted fruits. Parasitization and resulting fruit abortion can <br /> severely reduce the survival of a small population. <br /> • <br /> Finally, the reproductive strategy of L. bradshawii in conjunction with <br /> current •habitat conditions and `environmental stressors, such as drought and <br /> parasitism, may limit the survival and recovery of•the populations. All • <br /> currently known sites are relatively disjunct, 'separated by agricultural or :L.. <br /> urban.development, distance,'and /or topography Moat sites also have <br /> relatively few plants and /or are small.in size.. Isolation; "decrease in seed <br /> • ,dispersal, and selfingcombined could promote inbreeding, limiting gene flow, • <br /> and the reproductive capacity of L. bradshawii. • <br /> Description 2f thQ proiect.Area <br /> L. bradshawii occurs in approximately 7 acres of wet prairie habitat in.Amazon <br /> Park in Eugene, 'Lane County; Oregon. The Recovery Plan states that . <br /> approximately 750• flowering plants exist within. the park,. but the origin of 1 <br /> this .estimate was not provided (USFWS'1993). According to the biological <br /> assessment, approximately 2500 plants were estimated to occur within the 'park <br /> in the•1,94, (Salix Associates 1994).. The methods. used to, determine these <br /> numbers were not reported in either document. The nearest populations outside . <br /> of Amazon Park are'located in an area•called West Eugene Wetlands in the : • <br /> . • Recovery Plan The West Eugene Wetlands include Willow Creek Preserve (owned <br /> by the Nature Conservancy)` and other parcels owned privately and by the Bureau. <br /> of Land Management. According to the West Eugene Wetlands Plan (Cityo.f <br /> • Eugene- 1992),•the Bureau Of Land Management intends to acquire additional <br /> . parcels as they are available for the conservation of native. prairie habitats. <br /> - • The West'Eugene Wetlands are loosely connected to'Amazon Park by Amazon Creek, <br /> which flows northwest from the park.:: .. . . <br /> The'impact area comprises 0.45 acres of disturbed wet prairie habitat. It has <br /> 'been heavily invaded by introduced grasses and :herbaceous ` plants.. There are <br /> no trees or shrubs in the area due to frequent mowing. Foot and bike paths • <br /> and fill separate the area'from more extensive L. bradshawii populations` . <br /> • <br />