The objective of this component is to adapt and extend a coupled physical biological 1-D model to investigate production dynamics of the pelagic ecosystem as it pertains to survival of larval pollock. The approach uses field observations to determine rates and appropriate species composition for several of the distinct physical [ Coachman, 1986] and biological [ Smith and Vidal, 1986] domains in the eastern Bering Sea. The present model includes stage-structured dynamics of copepod populations ( Calanus and Neocalanus) and larval pollock feeding and growth (S. Bollens, pers. comm.). The temporal behavior of the mixed layer comes from observations (see below). Model results include that the species composition of zooplankton has a strong influence on growth of larval pollock; the presence of protozoan prey becomes important when young copepods are scarce (i.e., early spring over the slope). Results from the model also suggest that variability of the mixed-layer depth has significant impact on larval growth by affecting lower trophic level production. These results have led to the addition of a research component that addresses the potential importance of protozoans as prey for larval pollock.