Because the nature and magnitude of species interactions are functions of the traits that species possess, understanding how individual traits affect performance is important to our understanding of community structure. To examine the relation between species traits and performance, we first assessed behavioral responses of two larval anurans to three predator species in the laboratory. We then correlated these responses with growth performance of the two anurans when they competed in the field. In the laboratory experiment, larval bullfrogs (Rana catesbeiana) and green frogs (R. clamitans) exhibited no reduction in activity or spatial avoidance to bluegill sunfish (Lepomis macrochirus), moderate reductions in activity and spatial avoidance of mudminnows (Umbra limi ), and large reductions in activity and spatial avoidance of larval dragonflies (Anax spp.). In the field experiment, these behavioral responses were directly related to corresponding reductions in growth of the anuran larvae. Thus, for both species, changes in growth in the field could be correlated to the behavioral responses observed in the laboratory. Further, proportional changes in behavior in the presence of the different predators appeared to be related to changes in competitive relations in the field.