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The BRB also occupies habitat off the NFS lands in Bear Lake on the Utah-Idaho stateline. It presence provides the States of Utah and Idaho with many management opportunities to recover BRB popula- tions (Nielson and Lentsch 1988). A cooperative effort between Utah and the FS provided Bear Lake Bonneville to the Strawberry Reservoir, Wasatch County, Utah. While outside its historic range, this transplant was designated as a management population for recreational purposes. An additional transplant of a pure population on the Wasatch-Cache NF, Rich County, Utah, was made to suitable waters on nearby Deseret Land and Uvestock Company lands for both management and conserva- tion purposes (UDWR 1996). The Lower Bear River basin consists of four sub-basins covering watersheds on the Bear River from Soda Springs, Idaho, to its entry into the Great Salt Lake. Approximately 1,323 historic stream miles occupy these sub-basins with 27% occurring on NFS lands in two NF's (Caribou and Wasatch-Cache NF's) (Table 6b). The assessment indicates the occurrence of six pure BRB populations inhabiting 5% of NFS land on the Caribou NF (18 stream miles). Population occupancy is only 1% of total historic habitat. Based in stream mileage and occupied habitat, BRB populations are estimated to be 85% extirpated on NFS lands and 87% extirpated within their historic range in all sub-basin waters. The occurrence of six BRB populations in three of the four sub-basins should not be viewed as a indication of overall population health within these watersheds. BRB occupancy is fragmented, isolated, and contains marginal habitats with status as "at risk, declining. (ARD). Recent genetic evaluation of these populations indicate their relative purity to bear resemblance to a remnant form of the BCT, but subject to continued threats from exotic species (hybridization) and human activities (dewatering channel morphology changes and grazing). BRB populations on the Caribou NF, have a status 45% "at risk, stable. (ARS) in 50% of the sub-basins and 33% .at risk, declining. (ARD) in 25% of the sub-basins. Two populations have .unknown. status in 2 sub-basins (Table 19). Habitat condition on BRB populations on the Caribou NF indicate 78% occupy fair habitats and 22% occupy poor habitats (Table 20). Habitat trend indicates 44% are stable with the status of 56% unknown. Factors indicated affecting habitat condition were identified as sedimentation (100%), water temperature (78%) , channel modification (66%) and lack of woody debris (56%). Grazing occurred on 78% of habitats and was indicated as the primary cause of habitat deterioration (Table 21). The presence of exotic fish, i.e., rainbow, brown and other cutthroat trouts which occupy same or adjacent accessible waters, is viewed as a threat to all Idaho populations (Table 9). Past and present inventories continue to provide information on presence and absence of BRB populations to help clarify the uncertainty of their status and distribution (Cowley 1995, Nielson and Lentsch 1988, Behnke 1980, Behnke and Proebstel 1995, Nelson 1990, Brown 1935). Overall BRB population status within five occupied Bear River sub-basins indicates all are .at risk., with the upper two sub-basins categorized .stable. (ARS) and lower four sub-basins categorized .declining. (ARD) status. Genetic verification has been accomplished for 37% BRB populations overall with meristic evaluations at 92%. Meristic evaluation for BRB populations on the Bridger-Teton NF are 100% complete, on the Caribou NF 89%, and the Wasatch-Cache NF 80%. Electrophoresis analysis accounts for only 22% of total populations but varied from Bridger-Teton NF (5%) to Wasatch-Cache NF (80%), with none completed on the Caribou NF. Only 5% of the BRB populations have had a mDNA analysis completed. The Wasatch-Cache NF populations indicate 40% mDNA validation with none completed on the Caribou and Bridger-Teton NF's. Nonhern Bonneville The assessment area includes that portion of the eastern Bonneville Basin bordered on the north by the Weber River sub-basin and the south by the Spanish Fork-Utah Lake sub-basin. The area 48