H. GRIZZLY BEAR 



1) Introduction 



Ihe grizzly bear, classified as a threatened species in Montana 

 (U.S. Endangered Species Act, 1973), is a native of the Kootenai 

 River valley. A variety of habitats over a wide elevational gra- 

 dient are required to fulfill the seasonal habitat requirements of 

 the grizzly bear. Formation of take Koocanusa inundated approxi- 

 mately 25,536 acres of terrestrial habitat which provided seasonal 

 habitat requirements for the grizzly bear population utilizing the 

 area of concern. Region One, Montana Department of Fish, Wildlife 

 and parks has ranked the grizzly bear eighth in management priority. 



2) Se^CT^aJl Habitat Preference 



Grizzly bears utilize a diversity of habitats during the spring 

 through fall period. After emergence from their dens in the spring 

 grizzly bears select snowchutes, ridgetops and low elevation ripar- 

 ian areas where succulent forage high in proteins, sugars, and fats 

 is readily available (Jonkel 1982). Mealey et al. (1977), Singer 

 (1978), and Servheen (1983) have documented the importance of stream 

 bottoms, wet seeps, and alluvial areas during the spring. The high 

 water table and alluvial soil deposits in these areas support diverse 

 communities of mesophytic shrubs, forbs, and grasses. Forested types 

 containing these same types of plants, as well as security cover, 

 are also heavily utilized by grizzly bears (Mealey et al. 1977). 

 The succulent vegetation reduces the physiological stress the griz- 

 zly bears undergo during the weight loss period from den emergence 

 to the early summer when berries start to ripen (Jonkel and Cowan 

 1971). In some areas big game carrion is an important spring food 

 (Jonkel 1982). With the abundant big game populations wintering 

 along the Kootenai River valley, a ready source of carrion was 

 available as a food source for grizzly bears. 



During summer, grizzly bears are less restricted in habitat 

 selection because most grizzly bear range is snow-free, and many 

 habitats provide succulent vegetation (Jonkel 1982). Many bears 

 follow the "green up" to higher elevations during this period, and 

 movements to upper elevations can be abrupt, with little use of 

 timbered habitats at middle elevations during this period (Servheen 

 1983). As the various berries ripen in mid-summer, the bears take 

 advantage of this abundant, nutritious food supply to improve tlieir 

 fiiysical condition prior to denning (Jonkel 1982). The shrubfields 

 at the lower elevations ripen earlier and produce a downward 

 movement of bears (Pearson 1975) . 



Fall is a crucial time for bears because they must gain weight 

 rapidly in preparation to denning (Jonkel 1982). Rogers (1974) 

 reported a positive correlation between berry and niast production 

 and the productivity of black bears. During late fall, bears are 

 forced to lowland habitat where they take advantage of the available 

 food (scattered berries and succulent vegetation). Singer (1978) 



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