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In "Ninety fears of Salmon Culatre at Little ~ti'hite Salmon National Fish Hatchery," ~b'illiam R. Nelson and Jack Bodle give a poignant vignette. The hatchery, on the Little ~4'hite Salmon River near its junction with the Colum- bia in 1~1'ashington about ] "~ miles upriver fi-om Bonneville Dam, ++~as built in 1896 to boost the local fall run of Chinooks. Adults heading up the Little ~1~t~ite Salmon River were trapped to provide spawn for the hatchery. Besides raising mainly fall-run Chinooks in its first 90 years, the hatchery also pro- duced other fish, such as chum, sock- eye and cnho; later, spring Chinook. Annual fall Chinook egg take rose from 2 million in 1896 to 14 million by 1901 and peaked at 40.-1 million in 1917 (Figure 2). The dow~iward trend there- after was generally because returning adults were too fe++~ to provide enough eggs. At first thisw•as undoubtedh~ caused mostly by the intense, largely unregu- lated commercial fishing that had pre- vailed for years. Also, during the next 50 years, as fishing became more regtilated (but remainedgenerallyexcessive),changes occurred in hatchery operations, in- voking rearing the juveniles to greater ages and sizes (instead of releasing them as fry}, using more and more eggs from non-local fish (Figure 3), and feeding "prepared" diets (ultimate]}~ pellets), instead of liver, salmon eggs and car- casses. Some of the changes may have had adverse effects. In 1938 Bonneville Dam was closed. This affected salmon runs, disrupted hatcher}' operations by flooding, and forced hatchery reconstruction. In the 22 years before that, all but three broods had returned in sufficient numbers to pro+ide enough eggs to replace them- seh es. But af~ter+rard, egg take declined about 44 percent, and 14 of the next 25 broods returned in numbers too few to yield eggs enough to replace themseh~es. But until about 1980, except for a big dip in the 1940s (stemming from disruption of 193H-41 releases by Bonne+ille Dam closure) and a few later spells, annual release of fish from the hatch- ery was kept at around 12 million largely by importing eggs from other rivers: after 19EiK, no brood replaced it- self'. Fish marking studies sluit+-ed that after=release. sur- ~ i~ al of the hatchery fish had worsened over the years. At= ter 1976, local egg take un- dcrt+~ent steady decline to a l4iS"~ level so low (Figure 2}, that attempts to maintain the strain were discontinued. Failure of the Little 111~ite River stock of fall Chinook ~~ as attributed to several fac- tors. Bonneville Dam, besides c ausi ng nx)rtali t}' for fish pass- ingthrough the reservoir and dam, disrupted hatchery op- erations for several years. :11so, the intermingling of non-local (less well adapted) swains was cited as harmful: "The importation...ofnoruia- tivestocks occurred 4 tunes... in the first 50 years of opera- 0 a lion and 31 times in the past 38 years. In fact, from 1968 to a 1983, 51 percent of the fall Chinook salmon released in the Little ~~~iite Salmon River z were not native to the system. The eff~~t of these introduc- AC'I'l 11\ 199'2, Figure 2. Number of eggs collected each year from the loll Chinook salmon run in the Little White Salmon River, Washington, for use at its national fish hatchery, or for shipment to other hatcheries. figure 3. Total fall Chinook salmon egg take from the loco] river's spawning run at the Little White Salmon National fish Hatchery, combined with fall Chinook eggs imported from other rivers for use at the hatchery (Gne1 and the number of imported eggs (columns). As time went by, dependency on imported eggs in- «eased. Largely because of the hatchery, the loco] run was failing and could not replace itself.