Atlantic bluefin tuna has been added to the list of the most sustainable fish to eat following its resurgence in British waters, according to an updated assessment by the Marine Conservation Society. This development comes after years of global conservation efforts, which have helped increase bluefin populations to the point where they are now considered a "best choice" for sustainability.

Previously rated amber in Cornish waters for having room for improvement, bluefin tuna in this region have now been upgraded to green, the highest rating. Other UK waters were assessed for the first time in this update, and bluefin stocks there were also classified as green.

The update also highlights progress for several herring populations, which had sharply declined in the 1970s due to overfishing. North Sea herring fisheries, in particular, have been upgraded from amber to green following reduced fishing intensity and the implementation of long-term management plans.

Technological innovations are playing a role in improving sustainability for some species. Fishermen harvesting European king scallops in Lyme Bay, Devon and Dorset, have introduced LED-lit pots that attract scallops, dubbed “disco scallops.” This method reduces seabed damage compared to traditional dredging, though the species remains rated amber.

However, the guide also reports setbacks, with several species experiencing downgrades primarily due to overfishing. Hake caught in the North Sea, Celtic Seas, and Bay of Biscay has been moved from green to amber. Similarly, Dover sole has been cautioned against because catches exceed recommended levels in the North Sea and Channel, compounded by the inadvertent capture of plaice in the nets. Cod generally remains on the red list, indicating that it should be avoided to protect vulnerable stocks, though Icelandic-caught cod is an exception.

Brooke Schlipf from the Marine Conservation Society advised consumers to diversify their seafood choices by trying lesser-known species and recommended swapping cod for sea bass, which is currently faring well in UK waters. She emphasized moving away from the “big five” commonly consumed species—haddock, cod, salmon, prawns, and tuna—except for Atlantic bluefin tuna.

UK fishermen continue to face economic challenges, particularly due to rising diesel prices that have forced some operators in southwest England to sell their boats. Meanwhile, a recent increase in octopus populations has proven lucrative for some fishers, though it has also caused difficulties for others, as octopuses prey on shellfish stocks.

The Marine Conservation Society’s updated Good Fish Guide reflects these mixed trends, showing both positive outcomes in fishery management and ongoing concerns that require continued attention.