New reports uncover rampant seafood mislabelling

New reports uncover rampant seafood mislabelling

Nov 29, 2011
New reports uncover rampant seafood mislabelling

Yet another investigative report has exposed just how fishy the seafood business can be.

Last year, CBC Marketplace discovered that one out of every five fish they purchased in Canadian stores and DNA tested was mislabelled. It was the same result found by Oceana which tested seafood products in Boston supermarkets. And this summer, scientists published a study in Current Biology that found that eight percent of MCS-certified Patagonian toothfish sampled from U.S. retailers was not actually Patagonian toothfish.

Then, in October, the Boston Globe completed a five-month investigation that found a shocking level of seafood mislabelling in New England. Globe reporters found “that Massachusetts consumers routinely and unwittingly overpay for less desirable, sometimes undesirable, species - or buy seafood that is simply not what it is advertised to be.”

Now, in the December edition of Consumer Reports, the retail watchdog reports on DNA testing done on 190 pieces of seafood bought at retail stores and restaurants in New York, New Jersey, and Connecticut.

How routinely was fish mislabelled?

Consumer Reports found that 22 percent of fish was either mislabelled as different species, incompletely labelled, or misidentified by employees. 

By comparison, The Globe collected seafood samples from 134 restaurants, grocery stores, and seafood markets, and hired the Biodiversity Institute of Ontario to conduct DNA testing. The results showed that 87 of 183 products, or 48 percent, were mislabelled. The investigation focused on tuna and snapper, the species most frequently mislabelled. 

Here are the highlights of the Globe’s investigation:

  • 24 of the 26 red snapper samples were actually other, less prized species;
  • all 23 white tuna samples tested as some other type of fish, usually escolar, which is nicknamed the “ex-lax’’ fish because of digestive problems it is known to cause;
  • frozen fish at grocery stores was far less frequently mislabelled;
  • nearly all of the sushi restaurants surveyed replaced wild-caught red snapper with tilapia, a cheaper fish with significantly lower levels of healthy Omega 6 fatty acids; and
  • in one case, yellowfin tuna at a restaurant chain turned out to be bluefin tuna, an endangered species according to the International Union for Conservation of Nature.

While most tuna was properly labelled, Consumer Reports also found that red snapper was the most routinely mislabelled fish species.


In descending order of percentage mislabelled, by species or group.

Chart showing which fish were switched



This type of fishy business hurts everyone. From ocean to plate, the entire food chain suffers, except the culprits of course. Here's why we all need to be concerned about seafood mislabelling:

  • Consumers are unwittingly paying higher prices for cheaper species that often have lower nutritional value or higher levels of toxins, or which they may be allergic to.
  • Local fishermen have their prices undercut by cheaper fraudulent imports from afar.
  • The environment suffers since endangered species can be mislabelled and then sold to unsuspecting consumers or slipped through import bans.

Thisfish believes traceability can help take a bite out of this crime and reward those who responsibly harvest and handled your catch. Still, we all need to be vigilant when buying seafood. Here are some helpful buying tips.

Leave a Comment
Email Address: