As European-owned fleets have caught a third of all tropical tuna in the Indian Ocean over the last decade, companies based in the bloc have frequently reflagged their vessels to get around EU commitments to cut back on overfishing practices.

According to a report released by the Blue Marine Foundation and global investigations firm Kroll, companies from the EU are the beneficial owners — meaning they reap the financial benefits even if they don't appear as the registered owner — of more than 50 massive fishing vessels, known as purse seiners, that operate in the Indian Ocean. This comes as the EU has set a goal to cut back on the yellowfish tuna catch for European-flagged vessels by 21%, to allow dwindling populations in the Indian Ocean time to recover from years of overfishing.

"Despite the EU frequently pointing to the sacrifices and catch reductions made by its fleet, the reality is that EU-owned tuna fleets have gone from catching just over 220,000 tonnes of tropical tuna in the Indian Ocean in 1996 to more than 340,000 tonnes in 2024," the report reads. 

EU companies have sought to obscure their involvement in overfishing in the Indian Ocean and take advantage of more generous quotas in other countries by making the ownership structures of their purse seiners substantially more opaque, the report asserts. In one example, a purse seiner was found to have been flagged to the Seychelles, with a registered owner based in Curacao, and a beneficial owner based in Spain.

Over the years, EU firms have reflagged their purse seiners to an assortment of other non-EU nations, including Mauritius, Tanzania and Oman. European companies also account for the entirety of Seychellois, Mauritian and Tanzanian-flagged purse seiner fleets, which catch thousands of tonnes of tuna each year.

Overall, the 54 purse seiners identified in the report list more than 20 different companies as registered owners, many of which are small and local to coastal states along the Indian Ocean. However, the vast majority of those vessels are actually controlled by seven EU entities, while one — Spain-based Albacora Group — is the beneficial owner of a quarter of them.

The report notes that a wider collapse in tuna populations in the region would have the biggest impact on local coastal communities, which don't have the luxury of being able to fish elsewhere. Comparatively, EU firms would be the most insulated from the consequences despite bearing the largest responsibility, given that they can simply move their fleets to the Atlantic or Pacific Ocean as they see fit.