VI . SUMMARY 



The Libby Dam project inundated approximately 28,850 acres of 

 diverse wildlife habitats, including 3,314 acres of aquatic and 

 25,536 acres of terrestrial habitats, ^proximately 52.5 miles of 

 riverine habitat and 48.8 miles of tributary stream habitat were 

 inundated, including several backwater/slough areas adjacent to the 

 rivers. Twenty-nine acres of standing water were inundated by the 

 project. Riparian areas, totalling 4,051 acres, inundated by the 

 project included shrub, Cottonwood and mixed deciduous/coniferous 

 riparian habitats. Sub-irrigated grasslands/hay meadows, totalling 

 3,404 acres, were found throughout the valley floor; however, they 

 were concentrated north of the original townsite of Rexford. Non- 

 forested upland habitats interspersed with the forested types in- 

 cluded 1,583 acres of grasslands and 159 acres of upland shrublands. 

 The conife habitats were grouped into 5 gtineric types totalling 

 14,959 acres. Talus slopes totalling 16 acres were scattered 

 throughout the pool area. Developments totalled 409 acres and were 

 primarily associated with farmsteads, except for the areas asso- 

 ciated with the 3 towns ites. Loss of these habitats adversely 

 affected the diverse wildlife populations inhabiting the Kootenai 

 River valley. Quantitative and qualitative loss estimates were 

 developed for selected target species and species groups (Table 6) 

 based on available data descriptive of pre- and post-construction 

 population and habitat associations of wildlife species in the 

 project area and similar, nearby areas in northwestern Montana. 



Big game species inhabiting the area of concern were impacted 

 to varying degrees by the construction of the Libby Dam project. 

 White-tailed deer (1,467-2,221 animals), mule deer (716 animals), 

 bighorn sheep (78-102 animals), and black bear (43 animals) popula- 

 tions suffered declines due to the project. These loss estimates 

 were the basis for a qualitative loss estimate of high for each of 

 the species. In addition, beaver and ruffed grouse, both dependent 

 on the riparian areas, were also impacted at a level determined to 

 be high. A moderate to high level of impact was assessed for the 

 effects of the project on the Canada goose population inhabiting the 

 pool area prior to inundation. 



Moderate loss estimates were developed for the mountain lion 

 population (loss of prey base), populations of several species of 

 furbearers - muskrat, river otter, mink and bobcat - (loss of habi- 

 tat) , the seasonal (breeding) population of blue grouse, 2 species 

 of waterfowl - mallard and common goldeneye - (loss of breeding, 

 nesting and brood rearing areas), and the winter population of bald 

 eagle (loss of foraging habitat). Low to moderate qualitative 

 impact assessments were determined for the grizzly bear, wood duck, 

 and harlequin duck populations. These species incurred substantial 

 impacts; however, the impacts did not affect the regional popula- 

 tions to the degree other target species were impacted. 



A low level of impact was assessed for the majority of the 

 remaining species, including moose, pine marten, lynx, spruce 



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