Extensive copepod culture using a highly nutitious natural water source

摘要

Living organisms are currently the only suitable nutrition source for cultured marine fish larvae at the onset of first feeding, and some marine fish larvae such as red snapper (Lutjanus campechanus) have only been reared using copepod nauplii as the initial food. The traditional method for obtaining large numbers of copepod nauplii is to fertilize saltwater ponds to promote algal blooms which are grazed upon by copepods. Under these high-nutrient conditions, copepods can reach densities many timesgreater than observed in nature. The copepod nauplii are utilized when the population has reached peak levels either by stocking fish larvae directly into the ponds or removing them from the ponds and offering them to fish larvae in separate rearing tanks. An alternative technique for culturing copepods has been developed which eliminates the use of fertilizers by replenishing large tanks or small ponds with a natural source of highly nutrient-rich water. The Mississippi Sound is aver), productive andnutrient-rich estuary in the northern Gulf of Mexico, USA, which has been described as the "fertile crescent". The water from the Sound has a brown color resulting from dissolved organic material, suspended sediments, and phytoplankton, and has been usedto culture copepods at the Gulf Coast Research Laboratory (GCRL) in Ocean Springs, Mississippi.