Diet composition of larval Leiostomus xanthurus in and about the Mississippi River plume

Abstract

The diet of the larvae of the sciaenid fish Leiostomus xanthurus collected within the Mississippi River plume differs from that of larvae collected in adjacent Gulf of Mexico shelf waters. Larvae collected in plume water had eaten twice as many food organisms as had larvae collected in shelf waters. Larvae collected within the plume had eaten mostly small food organisms (tintinnids, copepod nauplii, pelecypod veligers and invertebrate eggs), whereas larvae collected in shelf waters had eaten mostly larger food items (copepodite and adult copepods). Differences in the abundance of food organisms in and differences in the photic environments of these water masses may account for the differences in diet.