Transition towards sustainable waste valorization from agricultural production systems: Insights from salmon aquaculture and aquaponics

Summary

This study focuses on optimizing waste streams from land-based Atlantic Salmon fish farms in Nordic countries. Fisheries are in a transition period as global demand continues to increase and global wild catch has plateaued. In 2016, the world passed a milestone where now over half of the world's fish supply is from fish farms. Nearly three quarters of Atlantic salmon are produced in farms. As the economic costs associated with sea lice and infection increase, and recirculating aquaculture systems technology improves, firms are now moving smolt production and even the entire production process (Langsand Laks) on land. It is currently more expensive to produce fish in these systems, but firms can receive a price premium for sustainably produced fish, particularly when marketed to high-end restaurants. We are witnessing the beginning of a transition in fish production to land-based systems motivated by sustainability: maximizing fish in/fish out ratios, and thereby minimizing waste (i.e., organic residue). Options for valorization of the waste production include integrated algae systems, hydroponic systems, and centralized processing operations that return the residue into the larger bio-economy. These technologies will therefore become more important in the near future. We conducted semi-structured interviews at two entrepreneurial firms: Langsand Laks in Hvide Sande, Denmark, and Aquaponics in Evje, Norway. We used a global value chain approach to structure the interview questions. In this study, we identify some potential technical, economic, and regulatory barriers and opportunities to the expansion of land based aquaculture and waste utilization. We find that regulation and entrenched food distribution regimes can hamper the development of novel systems like aquaculture. Furthermore aquaponic systems make more economic sense at larger scales.