The juvenile life history stage of walleye pollock Theragra 
chalcogramma (Pallas) in the Gulf of Alaska and in the Bering Sea, is 
critical to both the recruitment of adult pollock and the trophic web of 
the ecosystem.  Recruitment models of pollock indicate that much of the 
inter- annual variability in mortality occurs during the transition from 
larvae to early juveniles. Although the numerical abundance of a typical 
walleye pollock cohort declines throughout its existence, it has been 
shown that cohort biomass peaks at the early juvenile stage.  The high 
abundance of age-0 pollock, coupled with their high feeding rate, 
suggests that a high proportion of the ecosystem energy flows through 
this stage.  Some investigations of juvenile pollock food 
consumption have been conducted nevertheless,
the energetic demand of juvenile pollock 
in relation to prey availability is still uncertain, and it is still 
unknown what are the main factors that influence age-0 pollock population 
dynamics and distribution.  In this talk I will address the above 
questions by using a bioenergetics model.  Bioenergetics models have been 
shown to provide similar consumption estimates to other methods, and 
their utility in ecological applications is well established. Some 
results will be presented for a study in the Gulf of Alaska. Preliminary 
results will also be presented for a Bering Sea study, in the Pribilof 
Islands.  Specifically for the Bering Sea study, it will be discussed the 
application of spatially and temporally explicit bioenergetics model to 
understand juvenile pollock distribution and population dynamics.