SUSTAINABILITY logos on fish may not be entirely trustworthy. Some fish that the Marine Stewardship Council (MSC) have certified as sustainable come from unsustainable fisheries or are the wrong species altogether, according to a study of Patagonian toothfish (Dissostichus eleginoides), sold as “Chilean sea bass”.
Only one fishery, around the island of South Georgia in the Southern Ocean, is certified as sustainably fished by the MSC, so all Chilean sea bass (pictured) bearing the MSC logo ought to come from South Georgia.
They don’t, though. Peter Marko of Clemson University in South Carolina and colleagues bought 36 certified fish from shops across the US and checked their DNA. Three came from entirely different species and five carried genetic markers not found in the South Georgia population (Current Biology, DOI: 10.1016/j. cub.2011.07.006). “A significant proportion is coming from some other place,” says Marko.
Rob Ogden of the TRACE Wildlife Forensics Network in Edinburgh, UK, says the sample size is small for such a strong claim. “I don’t dispute their data, but I’m concerned with the strength with which it’s presented.”
The MSC is taking the finding seriously. “We are very concerned about the results,” says Amy Jackson, MSC’s deputy standards director. The group has launched an investigation. Whoever is responsible could have their certification withdrawn.