Underlying our work is the hypothesis that synchronous changes in sardine and anchovy growth rates across locations may be accounted for by basin-wide decadal-scale changes in environmental conditions. Where possible, we will combine long-term datasets on sardine and anchovy growth, with regional and local long-term climate and weather records, and use a common NPZ model coupled to the fish growth and dispersal model to examine consequences of environmental regime changes. Understanding how regime shifts in climatic regimes cascade up the food-web is a good opportunity for using past conditions to infer future effects of climate change.