Biological viability of producing white shrimp Litopenaeus vannamei in seawater floating cages

Abstract

In the last few years, in an attempt to foment the controlled culture of penaeid shrimp by artisanal fishermen communities, an innovative culture technology using floating cages have been developed in Brazil. In this work, we assessed the biological viability of culturing the Pacific white shrimp Litopenaeus vannamei in floating cages at different stocking densities in Santa María's Bay, México. Additionally, the influence of artificial substrates on growth performance of the shrimp was analyzed. Cages made of PVC-coated polyester mesh supported by wooden poles and PVC tubes were used for this study. Post larvae (PL) were stocked in four nursery cages at 700 PL per m 2. After 30 days of nursery culture, shrimp had reached an average weight of 0.5 g and were then transferred to grow out cages at densities of 100, 150, and 200 shrimp per m 2, with and without the addition of artificial substrates. Survival rate was neither affected by stocking density nor by the presence of added artificial substrates. In contrast, final shrimp weight was higher for those reared at low densities (100 shrimp per m 2) and the use of artificial substrates showed a positive effect on final shrimp weight. After 2 months of culture survival rate was above 90%, the shrimp weight ranged from 6.94 ± 1.51 g to 9.33 ± 1.48 g and yields varying from 818 to 1297 g/m 2 were recorded. The high shrimp production in floating cages was probably due to optimum environmental and rearing conditions provided to the shrimp. The present results confirmed the deleterious effect of high stocking density on shrimp growth, demonstrated the benefits of adding artificial food substrates to the cages, and proved the biological viability of culturing L. vannamei in seawater floating cages in México.