lack of riparian vegetation. 



Pine Marten. Most of the 25,536 acres of terrestrial habitats 

 inundated by the reservoir was assumed to be utilized by pine 

 marten. The 14,959 acres of coniferous habitats inundated by the 

 reservoir were assumed to be the preferred year-round habitat for 

 this species. 



Lynx. An undetermined acreage of serai lodgepole pine stands 

 and dense mature Douglas-fir and western larch were included in the 

 14,959 acres of coniferous habitats inundated by the reservoir. 

 Loss of these areas reduced the overall prey availability and 

 available home ranges for lynx, resulting in a reduction of the 

 population within the area of concern. 



Bobcat. Habitats inundated by the reservoir were probably 

 preferred by bobcats. It was assumed the impacts to this species 

 were fairly extensive due to the large amount of bottomland habitat 

 inundated. A loss of the available prey base and suitable home 

 range sites resulted in a reduction of the population within the 

 area of concern. 



5) Estimated Losses Due to the Project 



Due to the lack of population data for the majority of the 

 furbearers, quantitative loss estimates were not determined. Loss 

 of 14-31 river otter was estimated based on the densities (1.0 

 otter/ 2.7-5.8 km of waterway) observed by Melquist and Hornocker 

 (1983) . 



Qualitative loss estimates were based on the loss of important 

 habitats needed to support the pre-project populations. It was 

 assumed there was a high population of beaver within the area of 

 concern prior to construction of Libby Dam and the reservoir - 

 supporting marginal beaver populations - replaced the high quality 

 aquatic/riparian communities. Moderate populations of muskrat, 

 river otter, mink and bobcat were assumed to have occurred within 

 the inundated area. The total loss of the habitats supporting 

 these populations occurred, resulting in a total loss of the popu- 

 lations. Zackheim (1982) and Melquist and Hornocker (1983) 



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