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actively managed in Idaho. The Snake River, from below Hells Canyon Dam <br />downstream to the confluence of the Clearwater River, is the only area where there are <br />still significant numbers of fall chinook in Idaho, The Washington Department of <br />Fisheries, who share management responsibilities on this section of the Snake River, <br />started a monitoring program on fall chinook for this river section.. <br />Idaho is primarily managing three groups of anadromous fishes; summer steelhead, <br />summer chinook salmon, and spring chinook salmon. Steelhead and spring chinook. <br />salmon receive most of the management emphasis. In 1989, over 23 million hatchery <br />fish were released above Lower Granite Dam on the Snake River. Most of these <br />hatchery fish originated from production facilities located in Idaho. Some came from <br />Oregon's Grande Ronde and Imnaha River systems. Of the 23 + million, 9.6 million <br />were spring. chinook and 9.9 million were steelhead -- the 2 major hatchery species <br />reared in the state. <br />We reviewed 10 projects in Idaho; 2 were considered true supplementation, neither of <br />them was evaluated. <br />Steelhead <br />The potential Snake River steelhead run, based on run strength from 1954-1967, was <br />estimated for the Lower Snake River Compensation Plan (LSRCP) as 114,800 (Herrig <br />1990). In 1988, 99,714 steelhead were counted over Ice Harbor Dam. Although this <br />number is approaching the LSRCP goal, it is estimated that 70-80 percent of the <br />steelhead run returning to the Snake River are hatchery fish.l <br />Adult returns to the Snake River above Lower Granite in the past three years (1986- <br />1989) have. demonstrated a greater survival of wild fish over hatchery fish. Data for <br />steelhead indicate that 20 to 34 percent of the adult fish crossing over Lower. Granite <br />Dam are wild. These returns are from an estimated 10 to 18 percent wild smolts passing <br />Lower Granite Dam (Koski et al. 1990). This indicates as much as a two-fold survival <br />advantage of wild/natural steelhead smolts above Lower Granite Dam. <br />Idaho Fish and Game's Anadromous Fish Plan (Anon. 1985) established goals. of <br />returning steelhead and salmon. Steelhead adult returns indicate that the state is <br />nearing their goal of a smolt-to-adult survival of 2 percent for wild/natural and 1 percent <br />for hatchery fish. However, the total number of wild/natural fish returning to Idaho is <br />considered well below carrying capacity of the available habitat. <br />Idaho is in a very large hatchery program. Most of the stocking and outplanting has <br />been done with smolts. Most smolts have been released at hatchery racks and have been <br />1Larry Basham, Fish Passage Center, Portland, Oregon, pers. comm., April, 1990. <br />13 <br />