Experimental Rearing of the Golden Gray Mullet Liza Aurata (Risso, 1810) in a Recirculating System at the Black Sea

Abstract

Abstract Recirculating Aquaculture Systems (RAS) used in aquatic research and production are a viable alternative to traditional open-sea mariculture. The rearing of marine living resources in controlled environments is one of NIMRD’s constant concerns. Golden gray mullet Liza aurata (Risso, 1810) is spread in the Mediterranean, Black and Caspian Seas, as well as along the Atlantic coast, and culture in extensive and semi-intensive enclosures has been practiced worldwide for centuries, especially in the Far East and the Mediterranean, reaching a global production of 134,329 tons in 2010. The species’ potential for aquaculture is enhanced by its eurihalyne and eurithermal adaptability, allowing it to grow in a variety of ecosystems. The biological material used for the experiment was represented by golden gray mullet fingerlings fished using the beach seine from the Black Sea. They were monitored for health state, growth rythm (mean length and weight determinations), behavior under RAS conditions, survival rate and overall adaptability. The growth of juveniles after 90 days was 89.2% for total length and 246% for mean biomass. Concerning overall adaptability, after approximately one month, the golden gray mullet individuals fully adapted to rearing in the RAS tanks and handling during measurements. Moreover, the food administered (Skretting Classic K) was easily accepted, active feeding behavior being observed even in the presence of NIMRD’s staff. The fish’s health state was good, with no mortalities caused by infections or parasites. The survival rate upon completion of the two monitoring months was 76.66% (23 of the 30 individuals included in the experiment). The preliminary results obtained showed a good adaptability and a normal growth rate, which makes Liza aurata a potential candidate for aquaculture targeting the national and regional market.