Grieg Seafood harvested approximately 8,200 tonnes of gutted weight fish during the first quarter of 2026, according to a trading update released on April 8. The company noted that environmental challenges and specific treatment decisions impacted its operations in Rogaland.
Following a period of high seawater temperatures in the second half of 2025, the group faced increased sea lice pressure and lower survival rates.
Grieg Seafood responded by initiating mechanical delousing treatments before a period of prolonged cold water temperatures began in the first quarter of 2026.
The combination of these thermal changes and the mechanical treatments reduced the share of "superior-quality" fish to 60 per cent. This resulted in lower price realisation and higher farming costs for the harvested volumes, the company stated.
Grieg Seafood estimated the total impact on its profit for 2026 will range between NOK50 million ($4.7 million) and NOK75 million.
The majority of this financial impact is expected by the company to be recognised in the first quarter of 2026. The group has discontinued the specific mechanical treatment used during this period.
"This outcome is not satisfactory, and decisive actions have been implemented to avoid similar situations in the future," Grieg Seafood stated.
Most fish currently in the sea and scheduled for harvest later this year were not subjected to the discontinued treatment. The company considers the incident a one-off event that does not reflect its historical performance in the region.
The average number of treatments per post-smolt group has remained below one despite the recent increase in activity. Grieg Seafood plans to publish a more detailed trading update for the first quarter on May 21.