"We call them the zombie ships. They are the un-dead," said Sara Holden, by satellite phone from a Greenpeace boat off West Africa. "We came across them here, literally appearing out of the gloom. We thought they were abandoned, rusting ships, but as we got closer we realised there were people living on them."
Holden was describing a dozen Chinese fishing boats that are crumbling into the Atlantic - floating scrapyards with fallen masts, broken machinery, gaping holes and snapped cables. "If you sneezed, they would fall apart," she said.
The crews are fishermen, unable to work for lack of fuel, or because engines and winches have broken. They have no radios, navigation systems or basic safety equipment. They catch fish to eat and have desalination kits for drinking water, but most are dangerously short of essentials. Some have been anchored like this for months, waiting, they say, to re-equip and start fishing again.
Zombie ships exist on the border of legality. They do not have licences because they are not currently fishing, but they are part of a larger fleet (many of them have the same name, such as Lian Run, followed by a distinguishing number) which does fish. They never visit a port, but are refuelled and unloaded by licensed ships at sea. Their catches are then transported to European ports to be laundered.
In ten days in Guinean waters, Greenpeace found 67 vessels bearing the flags of Korea, China, Italy, Liberia and Belize, of which 19 were unlicensed. Pirate fishing, it says, is depleting stocks and threatening the oceans and all who depend on them.
Greenpeace and its partner, the Environmental Justice Foundation, working with the Guinean authorities, seized the Lian Run 14 on 28 March. They saw it fishing without licence and then found fish boxes on board marked with the names of licensed boats.
Greenpeace says many countries can't cope. "The Guinean authorities only have the type of skiff you'd use on a canal to patrol their territorial waters," said Holden. "We want to show that the responsibility lies with all states, not just the countries whose waters the ships are in, but also the countries from which the ships leave, and those where they port." And as Las Palmas is known as the fish-laundering capital of the world, Greenpeace says, the EU is particularly to blame.
While the oceans are being plundered, the fishermen are victims, too. Some have been at sea for two years and have no prospect of getting home. One zombie ship sank last year, taking its crew of 14 to the bottom with it.