Never mind the dolphins – what about the turtles and sharks?

The tuna fishing industry has reduced its impact on dolphins, but we still need tougher measures

Andy Tait, guardian.co.uk 14 Aug 08;

The campaign to make tinned tuna dolphin-friendly was, in many ways, a success. It showed that the tuna industry could respond to environmental issues.

But being dolphin-friendly is not the end of the story, because it's not the only sustainability issue when it comes to tinned tuna. Some tuna-fishing practices are responsible for wiping out thousands of sharks and turtles every year – including a number of rare and threatened species.

Most tuna for tins is caught using "fish aggregation devices", or FADs, which are used to attract the fish. But they also attract a host of other species including turtles, sharks and juvenile tuna before everything around the FAD is scooped up in a huge net. On average, every time a FAD is used, 1kg of these other species will be caught for every 10kg of tuna. Research conducted in 2005 found that around 100,000 tonnes of so-called non-target species were caught worldwide. These and other problems with the tinned tuna trade are described in a Greenpeace briefing paper Tinned Tuna's Hidden Catch, released yesterday.

The story of tuna is depressingly familiar. Globally, up to 90% of stocks of large predatory fish have been wiped out according to some scientists. We are literally emptying our oceans of marine life and as we do so, we fish further and further down the food chain.

Years of bad management and over-fishing has left tuna itself in trouble. All 23 identified tuna stocks are heavily fished and nine are classified as critically endangered, endangered or vulnerable to extinction. Without effective management even the healthiest remaining stocks will risk collapse in the longer term.

The UK is the second biggest consumer of tinned tuna in the world, after the US. What we do in this country can have a big impact on the tuna industry. And the industry big brands can effectively decide how the raw product is fished.

In Greenpeace's Tinned Tuna League Table also released yesterday, the biggest brands – John West and Princes – who have about 60% of the market between them – have finished last and second last. They scored the worst against a list of sustainability criteria, including apparently indiscriminate use of FADs.

More progressive retailers such as Sainsbury's and the Co-op are moving to sustainable catch methods and sourcing practices. Sainsbury's even tell you on the tin that their tuna is entirely caught with pole and line. It can be done.

But better catch methods alone aren't enough. Marine reserves are also needed to give migratory and other marine species some refuge from fishing fleets. There is overwhelming scientific consensus of the need for large-scale marine reserves to let fish stocks recover from overfishing. Major seafood companies and retailers must act on this issue by supporting proposals for marine reserves and by refusing to accept any fish caught in proposed marine reserve areas.