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Managers in Alaska are doing some lake rearing of Chinook with fish from the Gulkana Hatchery, a Copper River stock. Fed fry ate taken out by plane and planted into lakes in the upper Copper River. This pilot study has just started so no data on survival is available at this time. Sockeye Sockeye salmon are the premier commercial fish with outstanding market value. Therefore, production has increased in PNP and FRED hatcheries. Early hatchery programs suffered from chronic losses to IHN disease;. however, techniques for managing around IHN have now been improved. Also, techniques of both lake fertilization and lake production modelling have progressed so managers can strive for maximum production from rearing waters. Sockeye salmon in Alaska are planted into barren lakes or lakes with adult barriers and to supplement existing stocks. Lakes are usually only a few miles from salt water. A program of lake fertilization is done following a liminological study to identify needed fertilizers. Again, natural broodstock are used where possible. Excellent adult returns have been realized with smolt releases. Adult returns as high as 35 percent were documented at Big Lake. Biologists are expanding sockeye smolt releases because of the phenomenal successes. Following are survival rates of various stocking techniques: Sockeye stockings of unfed fry into lakes; expecting a greater than 1 percent survival in the Gulkana River area. Sockeye stocked in Summit Lake of the Gulkana drainage as unfed fry have returned at 0.8 percent as adults s Some sockeye smolt stocking into Big Lake have adult returns at a rate as high as 35 percent. Planting eyed eggs in upper Thumb River, a tributary of Karluk Lake, has increased adult returns to Karluk Lake and spawners to upper Thumb River. Eyed egg survival to fry is reported as exceeding survivals commonly obtained from natural spawners (White 1986). Fingerling sockeye released into Hidden Lake built up the production for the lake. It was believed spawning area was the limiting factor. Fingerling-to-smolt survival averaged about 20 percent and smolt-to-adult survival averaged around 15 percent (Litchfield and Flagg 1988). 3Ken Roberson, Alaska Department of Fish and Game, Glennallen, Alaska, pers. comm., January, 1990. 24