To model the state of fish populations, both individual
growth and the population number are necessary. Recently the PICES
MODEL Task Team has generalized ecosystem models for the North Pacific,
and applied the prototype model of lower trophic models (NEMURO)
for the growth of individual fish, at present Pacific saury and
herring. However, the same developments were not implemented at
the fish population level. Clearly, the abundance depends strongly
on reproductive success and fish survival during early life stages,
and these are, in turn, affected by the environment. This session
will review existing models and related scientific knowledge on
fish recruitment under varying environmental conditions, and create
a foundation for their incorporation in the ecosystem model for
the North Pacific and its regions.