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Figure 1. General success of supplementation with hatchery fish to returning adult. Good Success -- > --------------------- > ---------------------- > --------------------- > Poor Success Increasing length of freshwater residency Good Success -- > --------------------- > ---------------------- > --------------------- > Poor Success Increasing distance from ocean Good Success -- > --------------------- > ---------------------- > --------------------- > Poor. Success Increasing distance between stocks used Good Success -- > --------------------- > > --------------------- > Poor Success Lake rearing Main river rearing Stream rearing Introduced hatchery fish will augment the number of returning adults to a particular area, but if the factors which originally caused the natural runs to decline are not corrected, production will not significantly change. In fact, in some cases the presence of additional hatchery adults can lead to increased exploitation; thus decreasing the natural production even faster. In some studies, wild/natural stocks were shown to be more viable than hatchery stocks. Thus, replacing wild/natural fish with hatchery fish, and cross breeding wild/natural and hatchery fish, can result in less viable production. (Bjornjn and Steward 1990). If su~hplementation is ever going to be successful with hatchery fish, we must make major charges in hatchery management. We must make the fish as compatible with the environment (outplanting site) as possible. The hatchery mind-set works against fish- en~v~ionment compatibility. Changes that appear insignificant at the hatchery, e.g., wring program, outplant timing, and marking etc., can seriously affect the success of supplementation. However, when hatchery experts were questioned, 53 percent responded that fish culture decisions are based primarily on human efficiency not resource concerns (Diggs 1984}. ( Does supplementation of anadromous fish work? We believe that it can work, although success varies dramatically by (1) species, (2) stock, (3) area, and (4) method or type of f supplementation. Also, success depends on goals we are trying to achieve. If we look at natural production, we have very few successful examples. The two basic questions asked in the supplementation "Proposed Five-Year Work Plan", prepared by the Supplementation Technical Work Group (1988), are considered still quite valid. "What 39