On the basis of 14,564 spottail shiners (Notropis hudsonius) from Red Lakes, Minnesota, growth rates, strength of year classes, and food utilization were studied. Males and females had different body-scale relationships, and females grew faster than males. There was high correlation between water temperature and growth rate. Strength of year classes was closely related to size of spawning population. Food habits were related to food availability in both plankton and bottom fauna. Shiner eggs were significant items of food in larger shiners. Bottom organisms were selectively taken, and larger cladocerans were selected by large fish. Cladocerans were preferred to copepods.