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subspecies range but has not been quantified. The Montana and Idaho River Information Systems are lacking information for .population status. screens. Oregon noted that trap counts in 1992 from diversion screenings in the John Day River were 42% of the 10 year average (Kostow et a!. 1994). The Interior Columbia River Basin Project (ICRBP) is currently assessing the status of fish taxa throughout the Interior Columbia River Basin. Westslope cutthroat trout was selected as a key taxa and their present distribution is being described across the assessment area The ICRBP (Draft Report) estimates that westslope cutthroat occupy 74% of their historic range but remain strong in only 13% of the historic range. Estimates were derived by status calls from fishery biologists for each 6th order Hydrologic Unit Code across the assessment area Resident westslope cutthroat trout have been pushed into fragmented headwater habitats where small population size increases the risk of extinction (Rieman et a!. 1993). Migratory forms appear to have suttered the greatest decline. Flathead, Priest, Pend Oreille, and Coeur d' Alene lakes are the only large, natural lakes within the range of westslope cutthroat trout. Losses have not been quanti- fied, but numbers are down. Coeur d' Alene Lake, perhaps has the strongest remaining population which may be reflective of lake trout being absent (Dave Cross, Idaho Panhandle National Forest, personal communication). The maintenance of migratory forms is important in providing genetic exchange and for re-colonizing habitats after local extinctions. Westslope cutthroat trout populations appear to remain strong in roadless areas, wilderness areas, and Glacier National Park (Uknes and Graham 1988; Marnell 1988; Rieman and Apperson 1989), therefore it is readily apparent that human influence has greatly affected this subspecies. MANAGEMENT IMPUCATIONS Westslope cutthroat trout have evolved in relatively sterile environments. It is obvious that these high-quality waters that were once dominated by native fishes are declining. Native fish represent important intrinsic values that cannot be recovered when lost. If this natural diversity is to be retained, protection and restoration measures should not only focus on westslope cutthroat trout but on native species assemblages, including amphibians and invertebrates. Protection and restoration of aquatic assemblages will also need to focus on terrestrial habitats as the biotas are connected. Protection needs to focus on the remaining high-quality habitats, primarily those in roadless and wilderness areas. Preserve designs should consider: minimum population size to prevent losses from stochastic, demographic, and genetic events; distribution and replication of preserves to guard against catastrophic events; habitat and species diversity, and connectivity between preserves to promote genetic exchange while avoiding isolation. Protection of headwater areas will be essential in maintaining water quality. Protection should also focus on maintaining genetic integrity and diversity outside roadless and wilderness areas by safeguarding genetically pure populations against contamination and loss. Lastly, construction of barriers to prevent exotic species contamination may be a tool. However, population size and effects of isolation should be considered and their risks evaluated. Restoration will focus on rehabilitating degraded watersheds or removing undesirable non-native fishes. Many westslope cutthroat populations are isolated, where possible restoration should attempt to re-establish connections between isolated populations which will allow for natural recolonization in the event of catastrophies. Larger preserves that combine pristine habitats with restored habitats will be more resilient to natural disturbances. Restored watersheds will play a crucial role in any conservation strategy. 7