Production of market-size European strain Atlantic salmon (Salmo salar) in land-based freshwater closed containment aquaculture systems

Authors: CROUSE, CURTIS - Freshwater Institute; DAVIDSON, JOHN - Freshwater Institute; MAY, TRAVIS - Freshwater Institute; SUMMERFELT, STEVEN - Superior Fresh; GOOD, CHRISTOPHER - Freshwater Institute

Submitted to: Aquacultural Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/9/2020
Publication Date: 11/19/2020
Citation: Crouse, C., Davidson, J., May, T., Summerfelt, S., Good, C. 2020. Production of market-size European strain Atlantic salmon (Salmo salar) in land-based freshwater closed containment aquaculture systems. Aquacultural Engineering. 92:102138. https://doi.org/10.1016/j.aquaeng.2020.102138.
DOI: https://doi.org/10.1016/j.aquaeng.2020.102138

Interpretive Summary: Land-based recirculation aquaculture systems (RAS) are an increasingly used technology for commercial Atlantic salmon production with several new farms operating and other start-ups in planning and construction phases. Yet, Atlantic salmon performance data from land-based RAS is limited, particularly for European strain salmon reared through their full lifecycle in freshwater. Accordingly, eight groups of European-sourced Atlantic salmon were raised in freshwater land-based systems from fertilized egg to market-size food fish. Under these conditions Atlantic salmon reached 4-5 kilograms in 24.7 to 26.3 months post-hatch, and all-female salmon generally grew faster than mixed-sex groups. During a comingled production cycle, diploid all-female salmon grew faster than triploids; however, triploid salmon did not mature. Ultimately, selection of triploid stocks may reduce the risk of financial losses related to early maturation in RAS. This research provides data that will inform decisions regarding Atlantic salmon stock selection and optimize operational and financial projections for land-based salmon farms.

Technical Abstract: Interest in land-based farms using recirculating aquaculture systems (RAS) for market-size Atlantic salmon (Salmo salar) continues to grow, and several commercial facilities are already rearing fish. Performance data for commercially available mixed-sex, all-female, and triploid all-female Atlantic salmon reared to market-size in freshwater land-based facilities, however, are limited, particularly for European strain fish. Accordingly, eight groups of European-sourced Atlantic salmon (five groups of diploid mixed-sex fish , two groups of diploid all-female fish, and one group of triploid all-female fish) were reared from eyed egg to market-size in a semi-commercial scale land-based aquaculture systems over five separate production cycles to quantify performance metrics. Fish reached market-size (4-5 kilograms) in 24.7 to 26.3 months post-hatch. Fish were reared at a mean water temperature of 12.3 to13.7 degrees Celsius from first feeding to a mean size of 466 to 1265 grams, then 13.3 to15.1 degrees Celsius during growout. On average, all-female groups grew faster than mixed-sex groups; however, performance of individual cohorts varied. In a comingled production cycle, diploid all-female salmon grew faster than triploid counterparts. Early maturation rates ranged from 0 percent to 67 percent, with a mean maturation rate of 34 percent for diploid mixed-sex fish and 67 percent and 13 percent for two diploid all-female groups, respectively. Triploid all-female Atlantic salmon did not mature. This research confirms biological and technological feasibility of growing Atlantic salmon to market-size in land-based systems, but controlling early maturation of diploid salmon remains a challenge . This research provides important data inputs to optimize operational and financial projections for existing and potential land-based Atlantic salmon farms.