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stream reaches (Behnke 1976, 1992, Brooks 1989, Hickman 1978, Thwaits 1907, Jordan and Ever- mann 1908, Suckley 1874, Yarrow 1875, Cope 1955, Dodge and Cain 1970). The Snake Valley sub-basins contain the most studied WB streams of the seven historically occupied basins (Behnke 1976, Hickman and Duff 1978, Duff 1988, Haskins 1993, 1987). Based on this information an estimated 277 perennial stream miles could have been present within these two sub-basins. Multi-land ownership information is included in this estimate, including NF, BLM, State, and private lands. In Nevada, only one WB populations on the HNF is a remnant population while the remaining three (and 1 BLM population) are transplants from remnant populations in the Snake Valley area While in Utah, two remnant populations occupy BLM lands in the Deep Creek Range (Behnke, 1976). The author discovered the two populations in the Deep Creek Range in 1974 following intensive surveys of WB historic habitats begun in 1972 in coordination with Dr. Robert Behnke, Colorado State University. Another "possible. WB population was discovered in the Pilot Range sub-basin in 1975, however, population sampling by the Utah Division of Wildlife Resources (UDWR) was not conducted until 1978; then meristic analysis by Dr. Rober J. Behnke confirmed this remote, sparse population to be a genetically pure Lahontan cutthroat trout of Pyramid Lake origin (Hickman and Behnke 1978, Hickman and Duff 1978). Considering recovery in the Snake Valley sub-basins, the WB currently occupies only 1.5% of its historic habitat. As an example of WB recovery needs, an estimated 102 stream miles (47 miles on NF, 25 miles on NPS, 27 miles on BLM, and 2.5 on other lands) are estimated to be needed for viable WB population recovery based on historical and current stream information, and the author's profes- sional experience in the area. The HNF stream mileages would account for 46% recovery while NPS could provide 24% of stream recovery. The NPS stream miles were historically administered by the HNF ownership until the creation of Great Basin National Park in 1986. Prior to 1986, the amount of WB NF historic habitat could be stated as 29% in Snake Valley, with a population occupancy of only 5% and a population extirpation of 95%. In addition, recovery potential for WB could be enhanced in cooperation with the Goshute Indian Tribe which indicates an estimated availability of 30 historical stream miles in the Deep Creek Valley portion of the Southern Great Salt Lake sub-basin (personal communication, Buzz Cobell, U.S. Fish and Wildlife Service). Current habitat assessment for the two occupied sub-basins' overall habitat condition is fair to good, and the trend is stable (Table 1 O). The HNF sub-basins rated as 50% good and 50% fair habitat, with grazing occurring on 100% of occupied streams and mining on 50%. There is also a significant uncertainty relative to condition and trend. Specific comments pointed to on-going land activities, i.e. mining, grazing and roading, coupled with stream de-watering, changes in channel morphology, and terrestrial erosion - instream sedimentation as major factors influencing habitat (Table 11). The two WB populations (one remnant and one transplanted) on HNF within the Bonneville Basin could be classed as having a "at risk, stable" (ARS) status due to these on-going activities. The three WB transplanted populations outside the Bonneville Basin have a .stable and expanding" (SEX) popula- tions; the two populations in the Deep Creek Range could be classed as .at-risk, declining" (ARD) , but on-going and future management by state and federal agencies could enhance the stability of these populations (Table 12). Genetic verification has been completed on all populations on HNF through meristic and electro- phoresis evaluation. The one remnant HNF population has been verified genetically pure through mDNA analysis (Table 7). Rainbow trout and other hatchery cutthroat were identified as exotic species and a threat to WB population recovery in all seven sub-basins. These exotic species were present in five sub-basins (71 %) including the two sub-basins occupied by WB populations. Hybrid- ization with exotics and mining are viewed as major threats to existing WB populations. Some quantification of population status is available from state wildlife agencies, in Nevada and Utah, but 45