Bluefin tuna in Cornwall's waters

The bluefin tuna was once an abundant apex predator in British waters. In the 1960s, these warm-blooded aquatic hunters disappeared. Overfishing pushed them to the brink of extinction in the eastern Atlantic.

However, Atlantic bluefin tuna have made a significant comeback along the Cornish coast, with sightings increasing since their reappearance in 2014. This resurgence is primarily due to better conservation efforts and the rising populations of small prey fish, like sardines, in UK waters. Researchers from the University of Exeter are tracking bluefin tuna to understand their migration patterns. These iconic fish return to British waters each summer and autumn before migrating across the Atlantic.

In Cornwall, Atlantic bluefin tuna have recently gained attention as some of the most valuable fish in the region. Their commercial catch is allowed under strict licenses. One notable example was a 245-kilogram bluefin tuna that was sold for over £3,400 at £14 per kilo. Cornwall's bluefin is highly prized for its quality and limited local supply, contributing to its high market value.

As of September 2024, the MMO (Marine Management Organisation) had granted 13 licenses to UK fishermen to catch bluefin tuna. However, they can only be caught by rod and line with lures, and a closely monitored system ensures that the fisherman reports as much information on the catch as possible. They are allowed one fish per day per trip.

At the end of 2023, the UK concluded its first commercial bluefin fishing season in over 60 years. Now, scientists are cautiously celebrating a "remarkable" resurgence for the fish, signalling hope not just for the bluefin tuna but also for coastal communities that once relied on it.

The programme, known as 'Chart,' allowed ten boats to catch 39 tonnes, equivalent to a few hundred fish.

Over 3,000 bluefin tuna were tagged over 1,647 fishing trips during the programme between 2021 and 2023. A socioeconomic study of the scheme estimates that it gave a £2.6m economic boost across the bluefin-fishing season, which runs from mid-August to mid-December.

The increased availability of bluefin tuna has caught the attention of top chefs in Cornwall, who are excited to incorporate this sustainable, locally sourced ingredient into their menus. While overfishing led to population declines in the past, the species has since shown signs of recovery, with regulatory oversight from the International Commission for the Conservation of Atlantic Tunas. However, careful monitoring ensures that the population remains stable and sustainable.