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steelhead and 90+ percent of the chinook salmon smolts passing Lower Granite Dam in recent years, (1988 and 1989), are of hatchery origin.l Also, during the past 20-30 years wild/natural escapement has declined., The Columbia River Fish and Wildlife Plan of 1987 established the goal of doubling the salmon and steelhead runs from 2.5 million to 5 million. A cornerstone of this program is to fully utilize available habitat to increase wild/natural production. Although we have been producing hatchery fish for many years in the Columbia River Basin, there are still many unanswered questions concerning the use of hatchery fish for supplementation. The 1987 Columbia River Basin Fish and Wildlife Program, Section, 700 (h), recognizes this problem and stated, "Bonneville shall fund research to determine the best methods of supplementing naturally spawning stocks with hatchery fish, particularly in the upper main stem Snake and Columbia rivers." This analysis of supplementation was undertaken to assist in directing which areas of research needs to be prioritized for supplementation in the upper Columbia River. Priority species are upriver chinook salmon and steelhead. The Snake River is the drainage of highest priority. RESULTS General Our review points out the importance of a potential genetic impact from supplementation with hatchery fish. The concern expressed in the published literature review (Steward and Bjornn 1990) and from interviews, indicate that hatchery fish introduction could adversely impact the natural stock. Researchers are attempting to document -any genetic impacts of supplementation. Procedures which are being used to minimize adverse genetic impacts include: 1. Using a proportion of the adults in the wild or natural run as broodstock. 2. Stocking practices should mirror the natural environment, i.e., size, timing, stocking density, and donor stock. 3. Limit the density of stocked fish to prevent displacement or competition with wild/natural fish. There are different perceptions to which supplementation procedures work. The adequacy of supplementation procedures vary regionally. Alaska hatcheries produce and 1Larry Basham, Fish Passage Center, Portland, Oregon, pers. comm., March, 1989. 3