Our Executive Director John Sauven, writing for comment is free explains why tuna, once the 'chicken of the sea', is now at grave risk from overfishing.
The MV Esperanza confronts overfishing and pirate fishing in the Pacific.
Tuna, particularly the canned variety, has long been one of the UK's staple foods and most of us probably have a couple of tin or two somewhere in our cupboards. More recently, we've been developing a taste for raw tuna, as sushi bars continue to spread throughout the country.
So, what's the problem? Tuna is a wild source of protein. We don't farm tuna; we catch it from the great oceans of the world. And that is where the predicament starts, because global tuna stocks, like those of other species, have been grossly overexploited and are now in big trouble. The iconic bluefin tuna, widely used in sushi, is critically endangered. Bigeye and albacore tuna are also under threat, while yellowfin tuna is in decline globally. Worldwide, up to 90 per cent of stocks of large predatory fish, including tuna, have already been fished out.
The organisations responsible for managing the international tuna fisheries have failed dismally. But where governments have failed, retailers, restaurants and consumers can help turn the tide.
Greenpeace is campaigning to stop the collapse of the world's remaining tuna fisheries, pushing for the creation of large scale marine reserves and changes in fishing practices to allow tuna and other fish stocks to recover.
This month, the Greenpeace ship Esperenza is confronting tuna boats that are fishing unsustainably in the Pacific. Meanwhile, today, more than 80 Greenpeace activists used nets and chains to close down the stands of five of the biggest and most unscrupulous tuna suppliers at the European Seafood Expo, the world's largest seafood fair.
The UK is a huge consumer of canned tuna on a global scale. We import well over 100,000 tonnes each year. Sushi sales are also increasing. So, what can we do as consumers?
First of all, look out for restaurants and retailers that show commitment to sustainable seafood when you eat out or shop. For example, it was hearing about the plight of tuna that leading UK sushi chain Moshi Moshi to the decision to stop serving bluefin in their restaurants and to adopt strict sourcing policies. Among retailers, Marks and Spencer has consistently topped Greenpeace's seafood sustainability surveys. Second, avoid red-listed species like bluefin tuna. (You can find a guide to these species here.)
Third, wherever possible, choose pole- and line-caught tuna, the most environmentally friendly way of catching the fish. Other methods of catching tuna, even when the cans are labelled "dolphin friendly", can be very destructive - killing rare giant turtles, sharks, juvenile tuna and many other fish species.
Sustainable seafood is part of the answer, but the science is clear that we also need a global network of no-take marine reserves, like national parks at sea, covering large parts of the oceans. Following the science, Greenpeace is calling for 40% of the world's oceans to be marine reserves, where no fishing is allowed.
By only choosing sustainable seafood in shops and restaurants, we can all make a difference. Alternatively, as professor of marine biology Daniel Pauly, of the University of British Columbia, has said, you don't need to worry about these problems - as long as your children like plankton stew.
