Is there enough zooplankton to feed forage fish populations off Peru? An acoustic (positive) answer

► Information on crustacean macrozooplankton and fish was extracted from acoustic data. ► Euphausiids were the macrozooplankton group that best fitted the acoustic patterns. ► The total macrozooplankton biomass was estimated to about 105 g m−2. ► This biomass estimation is in agreement with new findings in trophic ecology. ► It also supports current hypotheses explaining the system's high fish production.