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For spring Chinook, the survival of wild fish may be as much as three or fourfold greater than hatchery fish. For instance, the Idaho Department of Fish and Game has estimated wild spring Chinook smolt survival to adult in Marsh Creek at 1.2 percent back to Idaho with good flows at Lower Granite Dam. Rapid River Hatchery spring Chinook salmon on the other hand recorded smolt-to-adult survival of 0.3 percent with good flows at the dams Hatchery returns of 0.3 percent on good flow years and 0.03 on low water years indicates that adequate flows are necessary to enhance upriver stocks. Within the last few years, a number of satellite- fish rearing stations have been established in the Clearwater and Salmon River drainages (both tributaries of the Snake River). These satellite .stations are used for .trapping adults and also for partial rearing of juveniles. Satellite stations are programmed to augment the wild/natural runs present in some of the tributaries. Evaluations on the effectiveness of the satellite stations in Idaho have not been determined, primarily because of the relative newness on the program. However, escapement data and snorkeling counts of yearly fish are being documented. Summer -Supplementation of both spring and summer Chinook salmon is a relatively new program in Idaho. Summer Chinook salmon are supplemented primarily on the South Fork of the Salmon River. McCall Hatchery, which started releasing summer Chinook smolts to the South Fork in 1980, has produced significant numbers of smolts. The goal of that facility is 1 million smolts per year. During 1988 and 1989 1,060,400 and 975,000 summer Chinook smolts were released into the South Fork from McCall Fish Hatchery. The program in the South Fork entails a weir on the stream where the adults are trapped and eggs are taken. One-third of the fish are taken for hatchery production and the other two-thirds are passed upstream for natural production. Return rates from coded-wire tagged summer Chinook salmon released at McCall Fish Hatchery indicate a smolt-to-adult survival of 0.80 percent for brood year (BY) 1981, 0.44 percent for BY 1982, and 0.46 percent for BY 1983 (Herrig 1990). Idaho Department of Fish and Game removed natural barriers to allow passage of adult Chinook salmon to Johnson Creek, a tributary to the East Fork of the Salmon River. Summer Chinook fry were outplanted annually from 1986 to 1989. In the fall of 1889, 15 Chinook redds were counted above the removed barriers. Stocking of Johnson Creek is planned to be continued until natural spawning of adults seed the area adequately. Summary Idaho is working to rebuild runs of summer steelhead, spring and summer Chinook salmon in the Snake River Basin. Some streams are designated wild streams where no SCharlie Petrosky, Tdaho Department of Fish and Game, Boise, Idaho, pers. comm., February, 1990. 15