Variations in the feeding intensity of juvenile coho salmonOncorhynchus kisutchand chinook salmonO. tshawytschacollected in coastal waters of Washington and Oregon were examined with respect to year, month, and area of collection and to light intensity, chlorophyll concentration, zooplankton biomass, and salmon abundance measured at the location of capture. Although the absolute amount of food in stomachs increased with increasing predator length, there was not a significant relation between stomach contents (as percent body weight) and predator length for either salmon species. Variations by year and month (but not by area) of collection were significant when examined independently for coho salmon; area (but not year and month) of collection was a significant variable for chinook salmon. Chlorophyll concentration (for coho salmon) and light intensity (for chinook salmon) contributed somewhat to the variability in feeding intensity as determined by a multiple-regression analysis but the abundance of salmon at the location of capture did not. Feeding intensity of juvenile coho salmon was also positively related to the biomass of plankton in surface waters but not to the overall biomass throughout the water column. Feeding success was not adequately described by any one variable examined, apparently because of the interactions among the levels of each variable.