Norwegian salmon biomass grew 2.6% year-on-year at end of May, accelerating from near-flat growth of 0.3% in April, according to a sector flash from Arctic Securities published June 20.
The improvement came despite a 1.1% decline in fish numbers in sea. Average fish weight rose 3.8% year-on-year, feeding increased 9%, and mortality fell 51% year-on-year — the lowest monthly figure on record. Only 2.95 million fish died in May, against a five-year monthly average of 5.4 million.
Total biomass in sea reached 870,000 tonnes by end of May, matching August 2025 levels. Peak 2025 biomass was 908,000 tonnes, just 4.4% above current levels. Arctic Securities said this indicates farmers are already at peak licence capacity, which has driven a recent surge in harvest volumes.
The bank warned the update is “negative in terms of short-term spot prices and earnings momentum” and expects stocks to react accordingly on Monday.