Greenpeace in the UK has just released a ranking of Tuna brands based on a wide set of environmental criteria, including the way their fish is sourced. In some cases, the fishing method can mean death for large numbers of sea turtles and sharks, or threaten the long term future of tuna itself.

The worst of the worst is Britain's top selling brand, John West.

Sainsbury's came out tops, with only one red mark -- for their failure to express public support the concept of Marine Reserves to protect our oceans.