Norway farmed salmon mortality rate fell below 15% last year

The annual mortality rate for farmed salmon in the sea phase in Norway – the world’s biggest producer of Atlantic salmon - fell to an estimated 14.2% last year, the Norwegian Veterinary Institute said today. In comparison, the mortality rate in 2024 was 15.4% and 16.7% in 2023.

The calculations are made on the basis of monthly records of the number of dead and live fish farmers report to the authorities during the year, when producers in Norway harvested more than 1.4 million tonnes of salmon (round weight).

“Several players have reported lower loss figures in 2025 and the Veterinary Institute’s calculations support a positive development in terms of mortality risk for farmed salmon in the sea phase in 2025,” said Ingunn Sommerset, director of the Department of Fish Health at the Institute.

“It has been several years since the national mortality rate was calculated to be below 15%. It is nevertheless important that the systematic work to improve fish health and welfare continues, so that we can see a lasting decrease.”

The number of dead farmed salmon in 2025 is reported to be 54.9 million, which is a decrease from 57.8m in 2024 and 62.8m in 2023. In 2024, a marked increase in the number of salmon lost in the category “Other”, which is not included in the figures for calculating mortality, was recorded. The use of the loss category “Other” in 2025 is approximately at the same level as in 2024, so that the reduction in the number of dead fish from 2024 to 2025 cannot be explained solely by increased reporting in this category.

The Institute pointed out that there may be changes in the figures for 2025 due to subsequent reporting, which may result in some minor corrections to these overall figures.

Variation by area

There is still a relatively large variation in mortality between different production areas, which start at production area (PO) 1 in the south and end at PO 13 in the far north.

The largest decrease from the previous year was in PO 6 – Nordmøre and Sør-Trøndelag. There, mortality fell from 22.3% in 2024 to 14.6% in 2025. The largest increase is found in PO 9, Vestfjorden to Vesterålen, with 9% in 2024 and 16.1% in 2025. Production area 3 Karmøy to Sotra has had a particularly positive development in the last three years, from 25.7% mortality in 2023 to 17.5% in 2024 and 15.2% in 2025.

The Institute said it uses a well-documented and established method to calculate annual mortality. This is done by calculating an average mortality rate for each month, which is added together to form an annual rate. This can be converted into an annual mortality risk, which is given as a percentage. The method takes into account that the amount of fish in the cages varies throughout the year, and provides a good picture of the situation at the facilities during the relevant period and is well suited as an indicator of fish health and welfare.

Fish Health Report

“We will return to further interpretations of the mortality figures in 2025, as well as other factors that affect the health and welfare situation of Norwegian farmed fish, in the Fish Health Report,” says Sommerset.

The Institute’s Fish Health Report will be presented at an open event in Bergen on March 11.

The table shows annual mortality per production area, expressed as a percentage.