Eco-labeled seafood is not always what it seems

Aug 22, 2011

When you buy what looks to be a nice piece of certified sustainable fish at the supermarket, you'd like to think that's exactly what you're getting. Unfortunately, things aren't always what they seem, according to researchers who have analyzed DNA isolated from store-bought, eco-labeled Chilean sea bass and report their findings in the August 23 issue of Current Biology.

"We found that, for fish purchased in US groceries, not all those labeled as MSC-certified Chilean sea bass are actually MSC-certified Chilean sea bass," said Peter Marko of Clemson University. MSC stands for the Marine Stewardship Council, an international organization dedicated to recognizing and rewarding sustainable fishing.

In the case of Chilean sea bass, MSC certification labels should indicate that a fish was harvested from the only recognized sustainable Chilean sea bass fishery, a population living in waters surrounding the sub-Antarctic island of South Georgia and a nearby plateau called Shag Rocks, Marko explained.

In fact, some of the fish that his team purchased turned out to be other species entirely. Of those that were Chilean sea bass, some 15 percent were genetically distinct from fish collected previously from the certified fishery. One sample carried a haplotype (defined as a combination of genetic variants in known as ) that has only been found on the other side of the globe, in the southern Indian Ocean. Other haplotypes that the researchers uncovered amongst fish marked with an MSC-certified label commonly trace to South American waters, and still others had never been recorded before in previous genetic surveys.

"The simplest explanation for this result is that other species plus Chilean sea bass from other, uncertified are being added to the supply chain for MSC-certified Chilean sea bass," Marko said. Although unexpected, "the results are not exactly shocking," given widespread mislabeling in the seafood industry and potential profits to be made.

It isn't clear who is responsible for the misleading labels, given that fish pass through many hands from the time they are caught to the time they are purchased.

"There is no question that organizations like the Marine Stewardship Council are trying their best to guide consumers to sustainably harvested seafood, but it is currently difficult to guarantee the geographic origins of ," Marko said. He added that the MSC has been working on ways to confirm fishes' origins, and the new study may serve as a model for how to go about that.

The only thing it seems that concerned consumers can really do for now is keep Chilean sea bass off their dinner menus. "At a grocery or on a plate in a restaurant, Chilean sea bass from South Georgia looks the same as Chilean sea bass from other parts of the world," Marko said.

Explore further: Stanford researchers rethink 'natural' habitat for wildlife

add to favorites email to friend print save as pdf

Related Stories

Seafood stewardship questionable: experts

Sep 01, 2010

The world's most established fisheries certifier is failing on its promises as rapidly as it gains prominence, according the world's leading fisheries experts from the University of British Columbia (UBC), Scripps Institution ...

Gender-changing fish are studied

Apr 11, 2006

A University of New Hampshire scientist is trying to determine what causes sex reversals among black sea bass and how to prevent it.

Recommended for you

Plants with dormant seeds give rise to more species

Apr 18, 2014

Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster. More ...

Scientists tether lionfish to Cayman reefs

Apr 18, 2014

Research done by U.S. scientists in the Cayman Islands suggests that native predators can be trained to gobble up invasive lionfish that colonize regional reefs and voraciously prey on juvenile marine creatures.

User comments : 0

More news stories

Biologists help solve fungi mysteries

(Phys.org) —A new genetic analysis revealing the previously unknown biodiversity and distribution of thousands of fungi in North America might also reveal a previously underappreciated contributor to climate ...

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Ex-Apple chief plans mobile phone for India

Former Apple chief executive John Sculley, whose marketing skills helped bring the personal computer to desktops worldwide, says he plans to launch a mobile phone in India to exploit its still largely untapped ...

Filipino tests negative for Middle East virus

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.