In February, 100,000 fish were released in Atlantis and submerged 30 meters below the surface at the Skrubbholmen site south of Rørvik. The experiences are positive according to a new report.
This was the first time ever that salmon and biomass of this size has been put in a pen and submerged 30 meters below the surface. With 100,000 fish in the pen, the project is getting close to a normal operational situation and Project Manager Trude Olafsen can report that the growth has been good and that the fish learned to use the airdome.
Normal behaviour
“We are very pleased with the results so far. The fish quickly calmed down and resumed a good pattern of movement inside the pen. Close surveillance of the fish revealed normal behaviour and feeding pattern throughout the whole period. The growth was about the same compared to ordinary pens at the site. The conclusion is that the fish learned to use the airdome in order to fill the swim bladder sufficiently and that the fish welfare was good,” Olafsen says.
The fish, which is about 3 kilos, was treated for lice before it was released into the pen and was harvested in April (25,000 fish) and the rest in June. The project has done a few changes since the first round of fish, including the instalment of load shackles to get a better overview of how the environmental forces are impacting the pen construction. The control system with associated technology has been built into a container to allow easy transfer between barges.
Lice
"During the test period, the lice's life cycle and development in Atlantis did not differ significantly from what we know as normal / expected development in traditional surface pens. The results indicate that some larvae reach their infectious stage in the depth. Occurrences of deep-going lice have also been registered in other sites but at a lesser extent than in traditional surface pens. During this test period, there have been no control pens at the site that can be compared to the lice development in Atlantis and this makes it difficult to discuss and conclude regarding the lice's development in Atlantis,” Olafsen says.
The pen was deloused once during the production period.
The pen and belonging technology are certified after NS 9415. The first prototype of the system was completed in May 2019 at Gjerdinga – a site location owned by SinkabergHansen north of Trøndelag, Norway. Atlantis Subsea Farming AS is owned by SinkabergHansen, AKVA group and Egersund Net.
You can find more information in Norwegian at atlantisfarming.no.
Contact person: Trude Olafsen (TOlafsen@akvagroup.com), +47 91557400
