There is a paucity of information concerning the invertebrate food resources available to juvenile salmonids in the Columbia River as they migrate seaward. Construction of mainstream dams has altered the temperature cycle, flow regime, and substrate which indigenous invertebrates were adapted to. Studies on how the macroinvertebrate community has adapted to these alterations have been neglected. This study was undertaken to help fill this void. Macroinvertebrate drift samples were collected over a three year period in the Columbia . River downstream from Bonneville Dam. Samples were collected with a D-ring plankton net fished on the bottom for one-half hour. Two sites were sampled; Ives Island (RKM 230), from 1987 through 1989, and Lady Island (RKM 193), in 1988 and 1989.