Predation upon larvae of the pacific sardine Sardinops sagax by cyclopoid copepods

Abstract

Analysis of the zooplanktonic community during a diurnal cycle of sampling at the entrance of Magdalena Bay, during the period of highest reproductive activity of the Pacific sardine Sardinops sagax, showed the presence of 80 zooplanktonic taxa of which only the copepods Corycaeus truckicus and C. japonicus were observed attacking sardine larvae; predation upon eggs was not observed. Most attacks were observed during the early evening and were associated with a high larval abundance, and occurred mostly on larvae less than 7.5 mm standard length (SL). These findings support the hypothesis that marine carnivorous copepods account for mortality of small fish larvae to a high degree.