2.2. Rainbow trout All female, diploid, rainbow trout (Kamloops strain) obtained as eyed eggs from Troutlodge Inc. (Sumner, WA, USA) were used. All experimental fish were hatched on-site within a recirculating incu- bation system and then cultured within flow through systems prior to use in the present studies. Equal numbers of fish were stocked in each WRAS to begin each study. Rainbow trout were 151 t3gto begin Study 1 and 18t 1gto begin Study 2.Initialstocking densities for Studies 1 and 2 were 30 and 12 kg/m3, respectively. Maximum densities were maintained at s80 kg/m3.