I 



58 



4. Future lemd uses: In Montana, timber heirvesting in the Swam 

 Valley is likely to cxantinue in the future, particularly on 

 private forest lancJs (especially those meinaged by the Plum 

 Creek Timber Ocrpany) . 



UpOTi executican of Ruth CXmbey's will, the Naticavil Audubon 

 Society will beocrte the cwner of the Idaho site, and will 

 nanejge the area a a naturzLl area. 



In Washington, the habitat in Spokane County is increasingly 

 being inpacted by a rising population in the area. Iitpacts 

 front resultant rural development may adversely affect 

 habitat throu^ pond drainage, riparian alteration, 

 overgrazing, and polluticai (J. Gamon, pers. ootran.)- 



B. Qiltlvation. 



1. . Oontxolled prcpagaticn techniques: No informaticMi; cwing to 



the habitat ^Decificity of the species, ex situ propagation 

 fran seed may be difficult. 



2. Base of transplanting cultivated material: Unknot. 



3. Pertinent horticultural knowledge: None kncwn. 



4. Status and location of presently cultivated material: No 

 cultivated naterial known. 



11. Evidence of threats to survrival. 



A. Present or threatened destruction, modificaticn, or curtailment 

 of habitat or range. 



1. Past threats: The historical sites in Oregon and California 

 have not been relocated, despite recent surveys. In Oregon, 

 most of the historical locations are within urban or 

 suburtan areas which have been extensively developed in 

 recent times, and they are thought to have been eliminated. 

 Additicxially, construction of dams along the Columbia and 

 Willamette rivers has led to a decline of suitable pond 

 habitats. At the type locality on Sauvies Island, carp eire 

 abundant in pcMids which are connected to the Coluntoia River 

 during hi^ water periods; these fish then destroy the 

 aquatic vegetation (J. Kagan, pers. comm.). In California, 

 the historiczd collecticm from the vicinity of Hcward Lake, 

 in the Cocist Range, was not relocated in 1979 or 1980. The 

 status r^»rt by Griggs and Dittole (1979) suggested that 

 cattle grazing and traitpling may have eliminated the 

 population, thou(^ they recaranended further surveys earlier 

 in the season, before cattle eire allowed in the area. Ihese 

 past edterations have apparently extirpated H. aquatilis 

 from approximately crje- third of its known global range. 



