observed a fall concentration of grizzly bears along the North Fork 

 of the Flathead River. 



Many factors affect the time of den entrance, however, general- 

 ly grizzly bears enter their dens in November, often following a 

 heavy snowfall (Craighead and Craighead 1972). Dens are character- 

 istically located at high elevations in remote areas with steep 

 slopes, deep soils, and heavy snow accumulations (Pearson 1975). 



Competition for food resources plays a part in the distribution 

 of grizzly bears within the region. While grizzly bears are not 

 strictly territorial (Craighead and Mitchell 1982), male bears 

 utilize and defend activity centers distributed on the basis of 

 preferred feeding areas (C. Jonkel 1983, pers. commun.). 



3) Popula cion Status 



Limited information on the distribution and number of grizzly 

 bear within the area of concern is available. U.S. Dep. Agric. 

 (1965a, 1966) reported the presence of grizzly bears on both sides 

 of the Kootenai River. Unpublished files for the Kootenai National 

 Forest document the historical observations of grizzly bears within 

 the forest. These reports document the area probably did not 

 contain a large number of grizzly bears, although the bears were 

 distributed throughout the area of concern. 



The current grizzly bear recovery plan (U.S. Dep. Inter. 1982) 

 delineates occupied habitat in northwestern Montana. A gap between 

 the two occupied ecosystems - Northern Continental Divide and the 

 Cabinet-Yaak - exists along the Kootenai River valley where histor- 

 ical observations of grizzly bears have been made. This indicates a 

 decline in the population that at one time occupied at least a 

 portion of the area of concern. 



4) Assessment of Inpacts 



Formation of Lake Koocanusa inundated approximately 25,536 

 acres of terrestrial habitats that could have been utilized by 

 grizzly bears. Loss of this habitat had an adverse impact on the 

 grizzly bears within the area of concern by removing important 

 seasonal habitat components. Inundated riparian and forested areas 

 providing the mesophytic plants preferred by grizzly bears were 

 probably utilized by the bears. Upland grasslands (1,583 acres), 

 sub-irrigated grasslands (3,404 acres), shrub riparian (667 acres), 

 Cottonwood riparian (873 acres), mixed riparian (2,511 acres), up- 

 land shrub (159 acres), and a portion of the coniferous forests 

 (14,959 acres) provided important seasonal habitat components for 

 grizzly bears. The displacement from the preferred spring and fall 

 habitats caused the bears to utilize a smaller amount of optimal 

 habitat and probably caused the bears to use suboptimal habitats 

 and/or move to other areas. The use of suboptimal habitats 

 probably caused a reduction in the overall reproductive rate 

 similar to that found by Rogers (1974) for black bears. Lake 



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