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had low fry-to-smolt survival. The Stillaguamish River summer Chinook program is <br />currently set up to ,incorporate wild broodstock. The program is also- shifting from fry <br />plantings to smolt plantings with higher survival rates. <br />Chinook -The majority of supplementation work on Chinook in Washington is being <br />conducted by Indian tribes; outplanting approximately 9,000,000 juvenile- Chinook <br />annually. The main purpose of this outplanting is to enhance or establish a fishery. <br />Most of the fish are stocked as fingerlings (> 7,000,000), with survival rates for fingerling- <br />to-adult ranging from slightly less than 1.0 percent to 0.1 percent. Outplanted smolts <br />have slightly higher survival rates, estimated at around 1.0 percent (Appendix A). The <br />Yakima Enhancement Study documented survival for wild Chinook smolts-to-adults at 4.4 <br />percent in 1983, compared to only 0.05 percent for hatchery releases. Trapped <br />outmigrating smolts' had a higher survival rate for those fish that were acclimated and <br />volitional released. However, the survival to adults was the same as those not <br />acclimated (Fast et al. 1988). <br />Summer Chinook salmon are managed primarily for natural production in the <br />Wenatchee, Methow, Okanogan, and Similkameen Rivers. <br />One negative aspect of supplementation recently described was the "pied piper" effect of <br />planting hatchery fish on wild fish. Hillman and Mullan (1989) found that hatchery <br />releases of age-0 spring Chinook salmon in the Wenatchee River "caused" 38 to 78 <br />percent of wild .Chinook and 15 to 45 percent of wild age-0 steelhead to join hatchery <br />migrants unless wild fish could not see them. This early migration of wild age-0 salmon <br />and steelhead was considered a loss to production. <br />Chum -Most chum supplementation efforts in Washington are concentrated in South <br />Puget Sound and its small drainages. Like Chinook, a number of Indian tribes are <br />conducting supplementation work to enhance or provide a fishery. Review of the <br />database (Appendix A) revealed that within Washington over 20,000,000 chum fry are <br />outplanted annually with 0.07 to 1.0 percent return to hatchery. <br />Coho -Coho fry are widely stocked in many small streams in Washington with no <br />separation or differentiation made between hatchery and wild fish. Over 92,000,000 <br />juveniles were outplanted, in 1985 and 1986 combined, to augment harvest with little or <br />no evaluation. Releases of 395,800 yearlings to the Nisqually River has realized a 10-14 <br />percent return to the fishery (Appendix A). Fry outplants in the Chehalis Basin are <br />estimated to be 0.05 to 0.09 percent to catch as adults, depending upon stock.2 <br />ZRick Brix, Washington Department of Fisheries, Montesano, Washington, pers. <br />comm., April, 1990. <br />11 <br />