Claims Overfishing Narrative Does Not Fully Explain Mackerel Decline
Pelagisk Forening has challenged the repeated claim that overfishing alone is responsible for the current crisis in Atlantic mackerel, arguing that the explanation does not stand up to scrutiny when examined against revised scientific data.
In a joint article, Mariann Frantsen and Kristian Sandtorv of Pelagisk Forening say the situation for mackerel entering 2026 is serious, but caution that public debate has become overly simplified. The International Council for the Exploration of the Sea (ICES) advised a 2026 quota of 174,357 tonnes, a reduction of 70 percent compared with 2025.
According to ICES, the spawning stock biomass is now estimated at around 2.7 million tonnes, down sharply from levels recorded a decade ago. However, Pelagisk Forening notes that comparisons with earlier years are misleading because historical stock estimates have since been revised upwards.
Retrospective Stock Revisions Alter Historical Picture
The organisation points out that in 2014 quota advice was based on a spawning stock estimated at roughly 4.5 million tonnes, not the nearly 13 million tonnes that retrospective assessments later suggested. That upward revision was made years after the quotas were set, using updated models and improved data.
Pelagisk Forening argues that this raises legitimate questions about how quota advice might have differed if today’s understanding of stock size had been available at the time. Frantsen and Sandtorv state that it is difficult to reconcile claims of prolonged overfishing with the fact that the stock was later assessed to have been far larger than originally believed.
They also note that fishermen and some scientific voices warned more than a decade ago that mackerel abundance appeared greater than survey data indicated, and that food availability could become a limiting factor if the stock continued to grow.
Weak Recruitment Identified As Main Driver
According to Pelagisk Forening, the dominant factor behind the current decline is several consecutive years of very weak recruitment, meaning fewer young fish entering the stock. The organisation accepts that overfishing may have occurred in recent years, but says this cannot explain the longer-term trend on its own.
The authors argue that portraying overfishing as the sole cause risks distorting the debate and undermining trust, both domestically and internationally, at a time when difficult management decisions are unavoidable.
Reputational Risks For A Key Export Fishery
Mackerel remains one of the most valuable species for the Norwegian fishing industry, with exports valued at NOK 8.5 billion in 2025. Pelagisk Forening warns that an inaccurate public narrative damages the sector’s reputation in key markets.
Frantsen and Sandtorv say research institutions and scientists should be clearer in communicating that current evidence points to prolonged weak recruitment as the primary driver of the decline, and that revised stock estimates significantly change the interpretation of past management. They argue that failing to correct media portrayals centred solely on overfishing risks leaving an incomplete and misleading picture of the mackerel crisis.
