Case study of sardines and anchovies indicates that natural variability in marine populations is real and large in the absence of fishing

It took decades to realize the importance of different mechanisms of change, such as decadal-scale variability A combination of oceanographic surveys and paleo studies indicate that both population size and distribution of fish and many other marine organisms vary tremendously, perhaps coherently, in different regions of the world’s oceans

Previously unseen populations of anchovies suddenly appeared in sardine catches in the Gulf of California in 1986 Holmgren and Baumgartner, 1993 Ecosystem Management (hard) or Ecosystem Awareness (soft ecosystem management)

Climate Linkage Hypotheses (non-exclusive, non-exhaustive) Changes in basin-scale flow affect larval transport and survival (MacCall) Mesoscale eddies affect larval transport and survival (Smith) Energy flow through food web (productivity) determines larval recruitment (Chavez)

Hypotheses can be tested with sedimentary records

Santa Barbara Basin sediments indicate large climate changes in past 60,000 years that all living marine populations have experienced But future changes may differ from past changes

Fisheries lessons are selectively being applied to other regions (Namibia, spiny lobster, striped bass) Legal, economical and cultural changes are other important possibilities

Invest in technology to preserve fish at sea Find better uses and recipes Change cultural views Anchovy - cheap, nutritious The government subsidizes the soup kitchens, and the fish institute decided to use them to offer anchovy-based meals and to provide training in fish preparation (FAO). 10% efficiency

Sardines were once considered a tasty treat in California. It is time for another social and cultural regime shift!