The Marine Donut, in operation in Romdalsfjord, Norway.
Bluegreen Group
Bluegreen Group has released an update on performance of the Marine Donut during the summer.
The facility, a floating closed containment system which was acquired by SalMar in September 2022, was stocked with its first batch of salmon in May this year.
According to an update posted on the Bluegreen Group website, the first few months following stocking have been a success. Project manager Geir Andresen stated "the facility has delivered on all fish health parameters", with minimal fish mortality, no sea lice infestation, and the feeding system working as planned.
"The fish are thriving. We can see this by how they are evenly distributed throughout the water volume and are feeding well," the blog states.
The only issue the team encountered were "short periods with slightly lower water temperatures in the facility than expected, which slightly reduced the fish's activity".
However, "That’s a known issue. We draw water from a depth of 40 meters. It maintains a consistent temperature of around 8°C year-round," Andresen explained in the post. "This is in contrast to open net pens, which have warmer water temperatures in the summer and colder in the winter. The fish in Marine Donut will therefore have steady growth throughout the year."
The company says that its focus is now on optimization of operations and gaining valuable experience. The Marine Donut facility is now fully operational, and the team has identified the need to fine-tune aspects of sludge collection, dead fish handling, and flow patterns, which they are optimizing through real tests with live fish rather than computer simulations.
The facility is approved to handle 1,100 metric biomass tons (MBT). As they approach this capacity, a test will be conducted involving the removal of around 25,000 salmon. The remaining fish will stay in the Marine Donut until they reach a slaughter weight of 5.5 kg, expected in October.
Andresen notes that it usually takes 90 days for fish to grow from 2.5 to 5.5 kg, but since this is the first batch in the controlled environment of the Marine Donut, the growth rate could differ.