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<br />Overall, the assessment indicates that a total of 81 pure populations exist within the basin. The
<br />additional populations off NFS lands occur on other federal, state, and private lands. The total
<br />includes those which have been established from remnant populations. Populations occupying NFS
<br />lands account for 83% of BCT populations. The BLM lands account for 14%, while state, county, and
<br />private lands each support 1 % of BCT populations. Although the BCTs current distribution has been
<br />greatly reduced from its historical range, and existing populations throughout the Basin continue to
<br />remain at risk in overall status, the replicated populations tend to be secure, stable, and expanding
<br />within their occupied habitat.
<br />
<br />Other states within the Bonneville Basin, with shared responsibility for BCT management also consid-
<br />er special status for the subspecies. In 1987, Nevada developed an interagency "Bonneville cutthroat
<br />trout species management plan", in cooperation with the FS and BLM for management and restora-
<br />tion activities in the Snake Valley-Spring Valley sub-basins (Haskins, 1987). Nevada formerly classi-
<br />fied the BCT a "state sensitive" species, but in 1995 that designation was dropped, and the BCT
<br />classified only as a game fish with no special harvest restrictions. The BCT is considered a sensitive
<br />species and a species of special concern by: Wyoming, the Forest Service (FS), and by each of the
<br />four Bureau of Land Management (BLM) State Offices. Wyoming developed an interagency 5-year
<br />management plan (1993-1997) to govern management and conservation strategies between the
<br />state, FS, and BLM in southwestern Wyoming sub-basins (Remmick et aI. 1993, Binns 1981).
<br />
<br />Idaho considers the BCT to be a sensitive species. In 1994, Idaho developed an inter-agency "Habitat
<br />Conservation Assessment and Strategy for the Bonneville Cutthroat Trout", in cooperation with the
<br />FS and BLM. They also developed a separate, single drainage, Conservation Agreement (CA) for the
<br />Thomas Fork of the Bear River, in cooperation with the FS, FWS, and the local grazing association.
<br />The intent of these documents was to facilitate management designed to reverse the decline of BCT
<br />habitat and populations in southeastern Idaho (Skully 1993, 1995).
<br />
<br />RESULTS AND DISCUSSION
<br />
<br />This assessment of status and distribution is intended to both expand and reinforce earlier reports
<br />documenting the occurrence and abundance of the BCT (Hickman 19n, Duff 19n, Hickman and
<br />Duff 1978, Duff 1988, Behnke 1992, Kershner 1995). Current information is based on the results of
<br />questionnaires, interviews, ongoing field investigations, and professional knowledge of the subspe-
<br />cies over its entire range. In order to ease reporting and discussion, the findings will be presented
<br />by BCT population, group, location, and hydrologic sub-basins, by state, and by National Forest
<br />(Figures 2 & 3).
<br />
<br />BONNEVILLE BASIN
<br />
<br />The occurrence of the BCT within the Bonneville Basin since the desiccation of ancient Lake Bonnev-
<br />ille left the subspecies isolated in four separate, major geographic areas, namely the WB were
<br />geographically isolated in desert "island ecosystem" mountain ranges, while the three other popula-
<br />tions, i.e. BRB, NB, and SB occupied rather large riverine systems in major basins that contained high
<br />quality habitat and strong populations capable of dispersing within sub-basins supporting metapop-
<br />ulations. However, some populations, like the WB and SB forms, became isolated with no connectivity
<br />to larger waters due to occurrence in mountain streams separated by desert valleys. This assessment
<br />estimates that 90% of Bonneville Basin sub-basins historically contained the BCT (Tables 1,2). Since
<br />the Bonneville Basin occupies a four state area, several sub-basins are shared between the States
<br />of Utah, Nevada, Idaho, and Wyoming. The BCT occurrence in sub-basins will consider each State
<br />
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