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was expected. Usually this happens because management questions are not posed in ecosystem (whole-catchment) context and actions evolve as interferences with the natural ecosystem connectivity. The example of introducing Mysis as a forage stimulus for sport fishes in a very tightly coupled system interfered with the quasi-equilibrium of the Flathead Lake food web and produced atrophic cascade that ultimately displaced a critically important population of bald eagle. On a larger scale, influences far downstream may have unanticipated effects on the operations of the two large dams in the catchment. In particular, we are concerned that efforts to increase the runs of Pacific salmon and steelhead downstream in the middle and lower reaches of the Columbia River may interfere with mitigation efforts in the Flathead Basin and other headwater reaches that never contained anadromous fishes due to natural barriers. The plight of the anadromous salmonid fishery involves overharvest, continually increasing dominance of runs by cultured stocks (apparently at the expense of naturally reproducing runs, owing to genetic introgression and increased harvest), predation of wild and cultured smolts by resident fishes, highly variable oceanic survival, and passage problems created by the nine mainstem dams (Ebel et al. 1989). Prominent in this discussion is the fact that early summer flood crest of the Columbia River has been eliminated by storage of the spring spate in four large reservoirs (Hungry Horse, Dvorshak, Libby and Mica) in the headwaters. Historically, the flood pulse of the river not only flushed smolts along on their outmigration, it also stimulated bioproduction in the estuarine food web which sustained the fisheries (Simenstad et al. this volume). Recovery plans for the fisheries call for a water budget for the river that mandates "fish flows" that will very likely interact with the economics of hydropower production and the need for flood control in a manner that will introduce a large measure of uncertainty in operations of the headwater dams. Unless the needs of resident fishes directly influenced by these dams have equal priority with downstream objectives, mitigation of resident fish and wildlife in the headwater segments may be compromised by actions for anadromous fishes. Another related problem is the tendency of today's managers to use standardized methodology that often relies on little or no empirical data or data that have little or no predictive power at the ecosystem level. Because of the natural complexities of river ecosystems, the intractability of cumulative effects in large catchments and the cost of long-term data acquisition, managers too often tend to seek simple answers to complex problems. Often this involves nothing more than a formalization and synthesis of "best professional judgment" with no ecological rationale that is empirically based. 20