Recirculating Aquaculture Systems (RAS) are a proven technology increasingly employed in the freshwater stage of Atlantic salmon production. Over the last decade many salmon producing regions have already begun to take advantage of the potential benefits of RAS technology in order to increase production and the overall size of Atlantic salmon smolt produced. The experience from a number of commercial farms is showing that smolts produced in RAS show better production performance in terms of growth and/or survival in sea cages than smolts from FT systems, however there is a need to verify these observations in a controlled manner (Ulgenes et al., 2008; Kolarevic et al 2014).
This study describes the design and performance of a small research recirculation system used in the production of Atlantic salmon smolts. Two commercial strains of Atlantic salmon were reared from first feeding to smolt in this RAS unit, the growth and performance was compared with fish reared in a conventional flowthrough system. The final weight achieved by the RAS stocks was 280g – Stock 1, 347g – Stock 2 and the flowthrough system, 89g – stock 1, 110g stock 2. After smoltification the fish were transferred to the Lehanagh Pool Marine Research Site, Marine Institute and the performance was monitored through four months post transfer.
*Jamie.downes@marine.ie
Acknolwedgement:
This project is funded by the European Maritime and Fisheries Fund under the BIM knowledge Gateway fund 17/KGS/009.
References:
Ulgenes, Y., Attramadal, K., Terjesen, B.F., 2008. The motivation for using recirculation in Norway — a shift from the need for restricted water consumption to better control of the culture water environment and higher product quality. Aquacultural Engineering Society’s Fourth Issues Forum. Aquacultural Engineering Society, Roanoke, Virginia, pp. 80–93.
Kolarevic, J., Baeverfjord, G., Takle, H., Ytteborg, E., Reiten, B. K. M., Nergård, S., & Terjesen, B. F. (2014). Performance and welfare of Atlantic salmon smolt reared in recirculating or flow through aquaculture systems. Aquaculture, 432, 15-25.