Reports handed to EU claim vessels likely to have entered coastal states’ waters where stocks are dwindling

European fishing fleets have been illegally netting tuna from dwindling stocks in the Indian Ocean, according to data presented to EU authorities and analysed by expert groups.

EU purse seine (a type of large net) fishing vessels were present in the waters of Indian Ocean coastal states, where they were likely to have carried out unauthorised catches, and have reported catches in the Chagos archipelago marine protected area and in Mozambique’s exclusive economic zone.

Two investigations were made of fishing in the Indian Ocean, one conducted by the group OceanMind and another by the charity Blue Marine Foundation along with Kroll, the corporate investigation company. The first report found evidence, from the publicly available data published by the EU from its fishing fleet from 2016 to 2020, that EU vessels fished in the region, where the main catches include the skipjack, bigeye and yellowfin tuna species. Blue Marine Foundation subsequently established that the vessels were not authorised.

The second report, by Blue Marine Foundation and Kroll, examined data from ships’ monitoring software, called the automatic identification system (AIS), and found that some vessels in the region had switched it off, which could be an indication of unauthorised fishing.

Populations of tuna are under increasing pressure as industrialised fishing fleets cash in on the growing market for the popular fish. The expansion of tuna fisheries could lead to extinction, scientists have warned.

The latest NGO findings, presented to government representatives at a meeting of the Indian Ocean Tuna Commission in Seychelles this week, highlight the problem of illegal, unreported or unregulated (IUU) fishing around the world, and of EU vessels taking catches from the depleting stocks of developing countries.

The analysts also found instances where vessels had “gone dark” – turned off monitoring through the AIS, which transmits a ship’s position and is a safety tool that can also be used to ensure fishers keep within the rules – at key points, suggesting they may have engaged in IUU fishing.

Some EU vessels in the western Indian Ocean went dark for an average of three-quarters of the period from 1 January 2017 to 30 April 2019, according to the Blue Marine Foundation findings.

The Guardian has spoken to a person familiar with the licensing situation, who confirmed EU vessels have had no licences to fish in Somali waters since 2013. Blue Marine Foundation said the Indian authorities also confirmed they had not issued licences to EU vessels.

Anne-France Mattlet, the tuna group director for the EU fishing trade association Europêche, said: “The EU purse seine vessels did not fish in Somalian waters.”

An official for the European Commission said: “The EU has a strict zero tolerance for IUU. In order to fight IUU in the IOTC convention area, the EU has also tabled a proposal to establish a high-sea boarding and inspection scheme, based on the work already done within the IOTC.

“This would be an important tool to control better the fishing activities in the high seas and continue to fight against IUU fishing. We have also tabled a proposal to improve the traditionally weak IOTC compliance process, by putting more emphasis on the categorisation and follow-up to established situations of non-compliance.”

The spokesperson said fishing crews may have valid reasons for switching off their AIS technology, and that the transmission power and signal can vary from place to place.

“[Going dark] does not imply that they fish illegally. The AIS might be switched off under certain circumstances by professional judgment of the master,” the spokesperson said. “The information given by the AIS may not be a complete picture of the situation in the area and of the vessel’s activity.”

Charles Clover, the executive director of Blue Marine Foundation, defended its claims. “The report showing the locations of EU vessels is based on the findings of a study commissioned by Blue Marine Foundation and undertaken by OceanMind – a highly reputable organisation – which in turn was based on publicly available data reported by the EU and published by the Indian Ocean Tuna Commission on its website,” he said.

“This data shows, for example, evidence of fishing on the part of vessels flagged to Spain in the waters of Somalia, in 2017 and 2018, and India, in 2018 and 2019.”

He added: “There is evidence to suggest that some of these fleets are fishing in coastal states’ waters without any kind of authorisation and we call on the European Commission to investigate these instances as a matter of urgency.”

The Guardian also approached the Spanish government for comment.