1995 Sardine spawning biomass reaches 300,000 metric tons, highest since 1954. May be related to interdecadal shifts of the mid-1970s. 1997 Climate models forecast large El Ni o, and monthly CalCOFI cruises are scheduled to study its effects. 1998 Significant data are compiled on consequences of El Ni o to nutrient, chlorophyll, and zooplankton patterns in the California Current, providing a close look at links between ocean physics and biology. Spawning biomass of sardines exceeds 1 million metric tons for the first time since the CalCOFI surveys began in 1951.
Spawning biomass is an estimate of fish population based on a sample of fish eggs and plankton eggs.
A total catch should be a fraction of spawning biomass so that sufficient adults survive to reproduce.