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most information in questionnaires was based on qualitative appraisal of habitat and population health. Existing habitat conditions on NF's (Sawtooth, Wasatch-Cache, and Uinta NF's) while not rated in the questionnaire can be estimated to be in poor to fair condition resulting from land-use activities, such as, grazing, roading, and mining, with primary contributing factors of de-watering, channel morphology and streambank change, and streambed sedimentation (personal communica- tion, national forest biologists and state fisheries managers, 1995). The loss of species bio-diversity is considered by many scientists to be resultant from anthropogenic habitat fragmentation and is the single greatest threat causing this loss (Noss 1991). Current management opportunities for recovery of existing WB populations are identified in a specific interagency habitat management plan for Nevada populations (Haskins 1987), a Utah conceptual plan for native fishes (Schmidt et al. 1991), a draft Utah BCT conservation agreement and strategy (UDWR 1996), and HNF Forest Plan and wilderness area management goals and guidelines (Whelan 1993). Previous evaluations of WB populations document their uniqueness and differentiation from other sub-populations endemic to the Bonneville Basin (Behnke 1976, Duff 1977, Hickman and Duff 1978, Shiozawa, Evans, and Williams 1992). The genetics of the WB represent the most relict, pure form of BCT and management programs should protect and maintain its genetic integrity. Assessment data and management history sug- gests the Snake Valley populations are the most threatened individual population segment of the BCT in the Bonneville Basin. Due to BeT inter-population differences within the Basin any efforts for recovery of WB populations should be focused on genetic potentials originating in close geographic proximity to the source population (Shiozawa and Evans 1992). For example, in order to protect the unique genetic lineage of the WB, populations of the WB and NB should not be intermixed to accelerate expansion of the WB range. The presence of anthropogenic activities that continue to subject WB populations to habitat fragmentation greatly increases its chances of extirpation. Man- agement guidance at national levels has indicated that, for species survival, responsible managers must treat the causes of habitat disruption rather than just the symptom (National Research Council 1992). Bear River Bonneville This assessment area includes all six sub-basins within the Bear River drainage to the Great Salt Lake. The area contains populations of BCT designated herein as Bear River Bonneville (BRB). Sub-basins are differentiated by two upper Bear River basins (in portions of Utah, Wyoming and Idaho) and four middle and lower basins (in portions of Idaho and Utah). BRB populations will be discussed by State and by sub-basin occurrence. The BRB historically occurred in all six sub-basins, but currently occupy 83% of historic sub-basins, and are extirpated in one sub-basin (Table 2,3). The amount of historic sub-basin habitat was estimated at 1,958 stream miles. National Forest (NF) historic stream miles (Bridger-Teton, Caribou and Wasatch-Cache NF's) account for 29% of total historic stream miles. (Table 6b). A total of thirty-six genetically pure BRB populations occur, including one lake population (Lake Alice, WY, 231 surface acres). These populations occupy only 7% (140.5 stream miles) of total historic habitats and 25% of NF historic habitat (568 stream miles) in the six sub-basins. Based on the assumption that BRB occupied most usable perennial stream habitat on NF's, it is estimated that BRB populations are 65% extirpated on NF's, and 92% extirpated in historic waters in the six sub-basins. As more quantifiable information becomes available in the future refinement of occupancy, status can be ascertained with more certainty. 46