After our cameraman left the Esperanza, Greenpeace continued their journey, and captured these images of the world's biggest purse seiner, with a capacity almost four times larger than the New Guinea vessel. It's a Spanish ship fishing for Pacific tuna to stock European supermarkets. The presence of such large vessels, from countries that have already over-fished their own tuna stocks, has riled the operators of local fishing fleets, perhaps with some justification. Some biologists have recently warned that tuna populations in the Pacific will be crashing within five years unless urgent action is taken. Perhaps it's time to think again about the ways we fish. These pole and line fishermen are Solomon Islanders, and this fishing is a local industry. They target specific species, and mature individuals.
There's almost no by-catch - no sea birds, no sharks. And they can be selective, flicking juvenile fish off their hooks so they can grow and breed. Because it's impossible to hook every last fish in a school, some are always left to fight another day. And since the fish don't suffer for hours in nets, this meat is of a high quality. These fishermen may not catch as many fish as a purse seiner, but then, that's the point. Whether any fishing is sustainable depends on how many fish are caught, how many are left to breed and how many other species are caught by accident. But these fishermen may have got it about right. The Marine Stewardship Council assesses the environmental impacts of the world's fisheries, and they believe that pole and line fisheries have the potential to be approved as officially sustainable. So now it's down to us, the fish-eaters. It may cost a few pennies more to buy a tin of tuna labelled "sustainably caught", but it could ensure future generations can also enjoy a tuna sandwich, tuna steak or sashimi. And protecting the fish will ensure a healthy ocean for all the marine life of the Pacific. It will require international commitment and co-operation, but the whales are a reminder that it can be done.
For the whales, for the fish, and for ourselves, the way we harvest the Pacific is key to protecting this fragile ocean paradise.