SPECIES AND SYSTEM SELECTION FOR SUSTAINABLE AQUACULTURE IN THE REPUBLIC OF THE MARSHALL ISLANDS. SPAWNING AND LARVAL REARING OF THE STREAMLINED SPINEFOOT Siganus argenteus (QUOY & GAIMARD, 1825)

The Republic of the Marshall Islands, as other nations in the region are facing many severe upcoming challenges due to climate change. Coastal resources management are important issues in order to adapt to the increasing severity of this challenging changes. Aquaculture is a potential adaptation option to reduce the impacts on native populations .

The streamlined spinefoot , Siganus argenteus  inhabits  tropical coastal and inner reef slopes and lagoons , ranging from East Africa to French Polynesia.  They are predominantly herbivorous, accepting a wide variety of food in  captivity. They spawn pelagic eggs and the reproductive cycle is synchronized with lunar periods , producing eggs throughout the year.  These characteristics along with the fact that they are much appreciated locally ,  make it a potential species for aquaculture.

The aim of the research is to develop the basic technology for culturing S . argenteus in order to meet demand for seafood, food security and stock enhancement, encouraging and helping farmers and fishing communities to improve their socioeconomic condition supporting healthy ocean populations and ecosystems.

Several a ttempts on the larval rearing of this species were made .  Eggs  were  obtained from natural spawning after full moon  were incubated in 500 liter plastic tanks with green water . The eggs are spherical (diameter 700 µm), transparent, contain a single lipid globule. Recent hatched larvae (TL= 1.5 mm) are  transparent and  after two days (TL= 2.5 mm) yolk was already absorbed at 30 ° C.  Different feeding schedules, illumination and temperatures were tested. R esults showed that the seed production in captivity is feasible, the main factor to be considered is the size of the live prey at first feeding because of the small size of the mouth in the larvae of this species.