Predation on juvenile flatfish and recruitment variability

Abstract

Predation on juvenile flatfish may either dampen or generate variability in recruitment. In theory, predation mechanisms which dampen variability include particular types of functional and numerical responses of predators to prey density and density-dependent stage duration. Mechanisms which generate variability include spatial overlapping, variations in predator abundance, alternative prey availability and environmental effects on stage duration. There is good theoretical, circumstantial and direct evidence that density-dependent predation mortality dampens variability in recruitment and thus is a regulatory process. Evidence is presented that predation mechanisms may also generate variability in recruitment. Patterns of expected predation impact and future research directions are proposed.