El Niño related to changes in sardine spawning

Abstract

The Pacific sardine, an important species for commercial fishing, spawns off the coast of California. The area and quality of its spawning habitat have been observed to vary from year to year, sometimes changing with El Niño–Southern Oscillation conditions, but smaller‐scale mechanisms also play a role. To sort out the physical forcing mechanisms affecting sardine spawning, Song et al. used data assimilation, combining observational data on sea surface height, sea surface temperature, and salinity data with a physical ocean model. They then looked at how the physical mechanics could explain observed interannual variations in sardine spawning range and egg density