Last week Greenpeace claimed to have exposed an illegal tuna purse seiner, the "Queen Evelyn 168", in a pocket of international waters between Papua New Guinea and the Federated States of Micronesia.

Greenpeace activists checks on juvenile yellowfin and skipjack tuna in the hold of Philippine mothership the Kenken 888. ©Greenpeace/Paul Hilton

This Philippines-flagged vessel was at the site of a transfer of tuna between her sister vessel and a refrigerated mothership, the "Kenken 888". It is likely that a transfer of fish at sea involving an illegal vessel was about to occur, says Greenpeace, but the arrival of the organisation prevented it from taking place as the vessels immediately separated and fled.

"Transfers of fish at sea are well known to be facilitating pirate fishing around the world now we also have the proof of this in the Pacific. It is unacceptable that this is still allowed to continue", said Greenpeace Australia Pacific campaigner Lagi Toribau on board the "Esperanza". "The pockets of international waters between Pacific island countries are especially prone to pirate activities and should be closed down to all fishing. Transfers of fish should only be allowed to happen in port so they can be monitored properly."

A statement from Greenpeace states that the "Queen Evelyn 168" is not authorised to undertake any fishing activities in this part of the Pacific. All vessels were registered to the Philippines. The "Queen Evelyn 889" and the "Kenken 888" have legal permission to operate in this area. However, Greenpeace is demanding that tuna transfers happen only in port, where the amount of the catch can be accurately monitored.

"At-sea transfers result in massive underestimation of the Pacific tuna catch. For years tuna have disappeared unreported on motherships like this. The Western and Central Pacific Fisheries Commission - which is supposed to protect tuna from overfishing - is clearly failing to do so. The only hope for Pacific tuna fisheries and the tuna themselves is to close the Pacific Commons to all fishing as marine reserves and to ban all transfer of fish at sea," said Toribau.

Greenpeace activists later boarded the mothership with the permission of the ship's Captain and documented the contents of the hold predominantly of juvenile yellowfin and skipjack tuna. Activists obtained information from the Captain about six other transfers of tuna he had done over the last month in the same pocket of international waters. These transfers alone added up to 675 tonnes of skipjack and yellowfin tuna onboard and were mainly from boats flagged to the Philippines belonging to the same company, TPS Marine Industries.