Alternative barging strategies to improve survival of transported juvenile salmonids, 2006

During spring 2006, we conducted a study to test the hypothesis that releasing transported juvenile Pacific salmonids Oncorhynchus. spp to the lower Columbia River estuary at river kilometer (rkm) 10 would produced higher smolt-to-adult return rates (SARs) than releasing them just below Bonneville Dam at rkm 225. We speculated that releasing transported fish an additional 215 km downstream from the location presently used could decrease smolt mortality due to predation by piscivorous fish and birds. Adults returning over the next several years will provide data to test this hypothesis. Contract no. W68SBV60307671 Contract no. W68SBV60418618