We will test the primary hypothesis that coastward advection of bottom cold-salty water during intense wind-driven upwelling provides conditions conducive forE. pacifica(the more oceanic species) to move onto the continental shelf where they become abundant and available to predators “early” in the season each year. As a corollary, we will test the hypothesis that as upwelling relaxes “later” in the season each year,E. pacificamoves offshore where it is less available to predators, andT. spinifera(the more coastal species) develops, becoming the dominant euphausiid in shelf waters and predator diets.