NRS will cease production of triploid salmon by the end of 2023. Photo: NRS.

Triploid salmon use to be paused in Norway due to welfare concerns

Norway Royal Salmon is to wind up its use of triploid salmon over the next two and a half years because of welfare concerns about the fish and a decision by regulators to impose a temporary block on new triploid production.

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Triploid salmon have three sets of chromosomes instead of the normal two (diploid salmon). The extra set of chromosomes renders ther fish sterile so they cannot interbreed with wild salmon in the event of an escape but also appears to make them more vulnerable to disease.

 The use of triploid salmon is stipulated in 18 “green” licences held by NRS. Regulators recently altered the terms of the licences to allow the company to grow diploid salmon.

A significant effort

“In collaboration with the Institute of Marine Research and other professional institutions, NRS has for many years made a significant effort to develop and improve the production of triploid salmon,” the company said in a press release last night.

“One of the experiences with triploid salmon is that it seems to be more exposed to bacterial and viral diseases. As a result, NRS has had a dialogue with the Ministry of Trade and Industry, where the Ministry has come to the conclusion that they will adjust the condition of use of sterile fish until there is a decision of the authorities on whether triploid production is fish welfare sound or not.”

The Norwegian Food Safety Authority (NFSA) announced yesterday that it will not allow more projects for testing of the triploid salmon method other than the current NRS “TripWell” project.

“When the project is completed, the authorities will decide whether triploid salmon is a method that is suitable for safeguarding fish welfare,” said NFSA.

“The Norwegian Food Safety Authority will give its professional assessment to the Ministry of Trade and Industry, which will decide whether the method can be used in commercial farming.”

Separate units

The NFSA’s decision follows the Ministry of Trade and Industry’s changes to green permit conditions in March, which now state that use of sterile fish applies “as far as such use is permitted by the Norwegian Food Safety Authority”.

Diploid fish can be used, but diploid and triploid fish must be kept in separate units.

The NFSA has ruled that no triploid smolts shall be put in the sea after the spring of 2022, and that all production of triploid salmon in the sea shall be completed by the end of 2023. 

Three companies holding green licences with triploid salmon stipulations are affected by the decision – NRS, Nor Seafood AS, which is one of the companies under the NTS umbrella, and Wilsgård fiskeoppdrett AS, in which NRS has a 37.5% stake.

Predictability in production

NRS said: “In the period up to the end of 2023, NRS will gradually reduce production of triploid salmon and replace this production with diploid salmon. The other conditions for the green licences continue to apply unchanged.

“There is still a strong environmental profile on the green licences, and consideration for fish welfare has made an adjustment necessary until a decision on fish welfare soundness has been made.

“NRS is satisfied with the decisions of the Ministry of Trade and Industry and the Norwegian Food Safety Authority, and this clarification will give NRS predictability in planning of the future production.”