Impostor Fish

By Douglas Fox

illustration ©Christopher Zacharow/

One cool day in January 2006, eight students from Stanford University went on a shopping binge—and not for the latest iPods or Levi’s. They visited two dozen grocery stores, fish markets, and sushi restaurants and brought home 77 fillets of Pacific red snapper.

Back at the lab, the students snipped off bits of flesh, digested them with enzymes, and spun the DNA down in centrifuge tubes. They identified the species of fish by sequencing segments of DNA. Their results raised eyebrows all around.

Those generic strips of flesh might as well have been called marine mystery meat. Sixty percent of them came from species other than what was written on the label, including Pacific Ocean perch and tilapia.

It wasn’t the first time scientists had peeked under the cellophane. Other, seemingly isolated studies have found similar results. For example, in Florida a local newspaper discovered that 70 percent of fish labeled on restaurant menus as grouper were some other fish; in New York City’s Fulton Market, a New York Times survey revealed that six out of eight “wild” salmon fillets were actually farm-raised. In most studies, the sleuths usually end up exposing 25 to 75 percent of the fish as impostors. Yet despite the pattern, a certain denial somehow persists: the studies are local—a drop in the ocean of commercial seafood—surely, they’re not representative.

Stephen Palumbi, the fisheries biologist who led the study at Stanford’s Hopkins Marine Station in Monterey, California, didn’t expect to find so many species among the sample fillets. “We were very surprised by what we saw,” he says. “We didn’t expect species on the fisheries endangered list, and we certainly didn’t expect to see any tilapia.”

Shoppers might bristle at the thought of paying for Pacific red snapper at a sushi bar, only to eat tilapia—which should sell for half the price. But that is, in fact, what happened, according to the Stanford study. The implications, however, go way beyond that.

Pocket seafood guides telling us which fish to eat and which to avoid have become our trusted sidearms in the consumer-centered war on overfishing. But ichthyologic name-swapping undermines a key premise of these save-the-fish campaigns—that ordinary citizens can glean sufficient information from the marketplace to make sustainable choices.

The Stanford study, published in the June issue of Biological Conservation, suggests consumers often have no idea what they’re buying. (1) Labels be damned—and the public with ’em. “The ability of individuals to vote with their restaurant bill is pretty much short-circuited,” says Palumbi.

The handlers of seafood have long treated fish names with slippery finesse, replacing unappealing terms with more gastronomically mellifluous ones as the need arises.

Just as a Hollywood agent transformed Norma Jean Baker into Marilyn Monroe for smoother public consumption, so it went with the Patagonian toothfish. A businessman from Los Angeles discovered the five-foot behemoth one day in 1977, tossed aside as trash on a fishing boat in Chile. He brought her home, dressed her up as “Chilean sea bass,” and turned her into an icon of fine dining.

These makeovers sometimes even enjoy government support. The US National Marine Fisheries Service worked through the 1970s to rehabilitate the images of 18 “underutilized” fish species. Tensile strength, bulk modulus, and other measures of fish fillet texture were assayed at the US Army Natick Research Center in Massachusetts, using the kind of high-tech gadgets that would normally be deployed to test parachutes and body armor. Five-hundred thousand dollars later, the data were leveraged to rename fish according to their taste and feel.

Over the years, slimehead became orange roughy. Stumpknocker became spotted sunfish. And Pacific red snapper became a staple in grocery stores and restaurants across the western U.S. Except for one thing: there is no such thing as Pacific red snapper. This term—essentially a brand name—covers 13 different species of rockfish found up and down the West coast which the US Food and Drug Administration (FDA) allows retailers to sell under a single umbrella. But even that broad umbrella didn’t cover all of the fish that Palumbi’s students found hiding on store shelves.

Sixty percent of the fillets they tested fell outside the FDA’s 13 codified species. Among these were several nonsanctioned species of rockfish—aurora, blue, blackgill, and splitnose—and in sushi restaurants they found things as utterly unrelated as tilapia. All told, over half of the fillets that they tested belonged to species listed by government authorities as overfished (indicating a 75 percent decline from virgin biomass).

It turns any purchase of Pacific red snapper into a game of Russian roulette, says Cheryl Logan, lead author of the Stanford study. “There’s no way you can know whether you’re buying an over-fished species.”
No one knows exactly how often this shadowy practice of mislabeling occurs, but one thing is certain: the seafood trade is as messy as a fish-gutting factory.

Much of that mess arises from the global travels of a fish, beginning from the moment it’s dragged up on a hook. Salmon swimming in the waters off Alaska may be caught by U.S. or Norwegian fishing vessels, travel all the way to Vietnam for canning, then eventually find their way back to grocery stores in the U.S. or Europe.

A fish can change hands half a dozen times as it travels from hook to plate. Along the way it sheds its head, fins, scales, and other identifiable parts. “As distance from the hook increases and knowledge of fish decreases, the likelihood of mislabeling grows,” says Jennifer Jacquet, author of a recent paper examining the consequences of renaming seafood and a PhD student under well-known fisheries biologist Daniel Pauly at the University of British Columbia in Vancouver. (2) Pauly and Jacquet suspect that a lot of mislabeling happens at the hands of distributors and middlemen.

All told, the U.S. imports 80 percent of its seafood—and the FDA inspected only 0.59 percent of it in 2006. Fish imported into the U.S. usually carry species labels, but loopholes still allow fish to arrive under generic names such as “frozen fish fillet.” Contraband, such as illegally caught Patagonian toothfish, sometimes hides among the fish sticks. Even for legally imported fish, mandatory species labeling ends when customs is cleared. From then on, the fish fillet can indulge in that quintessential narrative of immigration: reinvention of the self and adoption of a new, sexier, more glamorous name.

Even when wrongdoers are caught, the fines pale next to the profits. Two fishermen caught poaching American sturgeon caviar in the 1990s paid US$17,375 in fines—compared to their estimated US$2 million in sales. “The picture is consistent,” says Pauly. “There’s lots of cheating going on in all Western countries.”

That deceit carries insidious consequences. “Why on earth should consumers think that any of these species are in trouble if they can always go to the grocery and find something called red snapper?” asks Peter Marko, a biologist at Clemson University in South Carolina, who has tested supermarket fish. “Mislabeling creates a warped perception in the public’s mind.”

Admittedly, mislabeling often shifts consumption from less-abundant fish species (such as grouper) to more-abundant fish (such as tilapia), a direction that should theoretically tilt consumers toward eating less-exploited fish—even if they don’t realize they’re doing it.

Unfortunately, that’s not how it works. Mislabeling and renaming drive a vicious cycle in which preferred species are depleted, only to be replaced by less-palatable fish which in turn are depleted and replaced by even less-palatable ones.

Consider our belated embrace of the slimehead and stumpknocker. “These fish were [originally] given such names,” says Jacquet, “because no one thought they’d ever end up on dinner plates in fine restaurants.” But as favorites such as Atlantic cod grew scarce, ugly-named stand-ins became our fish du jour. In the case of Patagonian toothfish and orange roughy, these stand-ins have themselves grown scarce.

The same goes for monkfish—a dumpster-mouthed angler which prowls the dark waters a kilometer below the surface. “In the 1950s or –60s you would have caught monkfish while fishing for cod, and you would have thrown monkfish away,” says Pauly. This ugly fish was never meant to see the light of day. But by 1997, culinary magazines hailed it as the poor man’s lobster. “They have to cut the head off,” says Pauly, “because it’s so ugly that it would be horrible to see.”

Restocking store shelves with successive waves of stand-ins also creates, and conceals, a geographic problem. Marko saw it in 2004 when he led a DNA study (similar to Palumbi’s) in which he and his students tested 22 red snapper fillets sold in the southeastern U.S.

The fish called “red snapper”—lest the reader misunderstand—bears no relation to those species of rockfish, found along the Pacific U.S. coast, which grocery stores sell as Pacific red snapper. Instead, red snapper represents a bona fide species, which inhabits coral reefs in the Gulf of Mexico, part of an entirely different family—the snapper family. Consumers consider red snapper top-dollar dining. But when Marko’s students tested fillets, they found 77 percent of them to be something else. Most of the counterfeits turned out to be other, less-expensive members of the snapper family; a few were lowly tilapia.

The tale of economic fraud naturally grabbed headlines when Marko published his results in Nature in 2004. (3) But something more subtle caught Marko’s eye. Nearly 40 percent of the fillets came from species found far from the Gulf of Mexico—such as crimson snapper, which ranges from India to Japan to Australia. Foreign fish feeding the U.S. appetite for dwindling red snapper concerns Marko. “Many of the countries that we’re getting these fish from don’t have the same kinds of fishing regulations [that we have],” he says—meaning that exhaustion of U.S. fisheries, or even careful management to limit catches, could lead to overfishing elsewhere in the world.

The problems plaguing consumer choice look a lot like those facing carbon credits, fair labor certification, and other market-based interventions. The likely solutions include tracking fish reliably from hook to plate and providing more complete information on the shopping label, including the exact species name, the farming or fishing method, and the country of origin. To do this, says Jacquet, “we need to work higher in the demand chain than just consumers.” In other words, target the likes of the U.S. seafood restaurant chain Red Lobster, global seafood brands and distributors such as Birds Eye, and governments that import fish.

Whole Foods Market has begun certifying its suppliers of farmed seafood for sustainability and is developing similar standards for wild-caught fish. Certification involves site visits by third-party consultants to ensure that suppliers meet Whole Foods’ guidelines. Those guidelines include a tracking system allowing each crate of fish to be traced back to its original hatching source, farming cage, feeding method, processing plant, and so on.

Wal-Mart has also pledged to develop sustainable, traceable seafood suppliers. And the London-based Marine Stewardship Council (MSC) (formed by a partnership between WWF and Unilever, a major buyer of seafood) has embarked on a program to audit and certify fisheries as sustainable—again, with a chain-of-custody component built in. MSC has certified 32 fisheries to date, with more in the pipeline. “They’re not doing it because nobody cares,” says Carl Safina, executive director of the Blue Ocean Institute. Industry eco-consciousness, he says, stems in part from the pressure applied by consumers who have become educated through these seafood guide campaigns.

Pauly, too, sees these efforts as laudable examples of what should be done. But he cautions that they’re not a complete solution. MSC-certified fisheries still account for far less than 10 percent of the worldwide fish haul. And while a few select stores can guarantee the identity of what they sell, much seafood consumption in the U.S. still occurs in restaurants.

“Chain of custody is a problem,” says Pauly. People in grocery stores can see certification labels on packages, but customers at restaurants have no such opportunities. Conversations with waiters and chefs often produce assurances that the fish on the plate is sustainable, that the swordfish is farmed (no such thing exists), or that fishermen make sure to release “pregnant” swordfish from the net (again, no such thing).

Pauly believes these basic problems will persist until government steps in with regulation, enforcement, and large penalties for mislabeling. He cites U.S. and European government agencies tasked with tracking down counterfeit Gucci bags and pharmaceuticals as examples of what could be done. Counterfeit Gucci bags can net millions in fines. Fake drugs can result in the shutdown of a business.

Government enforcement remains a lofty goal. Consider that the most visible mislabeling studies—Marko’s and Logan’s—were class projects. Another study, reported on August 21 in The New York Times, was done by high school students. (4) Others were commissioned by newspapers investigating local restaurants. These projects occupy the margins of fishery science, far from funding and grant priorities.

The problem of mislabeling arises not just from poor regulation, but also from consumers’ distorted expectations. There exists a fundamental mismatch between how consumers think of fish and how fish actually exist in the real world.

Western consumers, accustomed to a limited pantheon of domestic-raised meats and poultries, seem to expect that kind of uniformity in wild-caught fish. One might call it the comfort of having familiar choices—but only a few choices—on store shelves.

These expectations may encourage retailers or distributors to shoehorn a fish with the wrong-colored spots into a familiar bucket, such as red snapper, Pacific red snapper, or cod. “I don’t think there’s a grand conspiracy,” says Palumbi; “I think vendors have found it easier to call things by generic names that people kind of recognize.”

But what if every single species of rockfish, dogfish, snapper, and cod were labeled correctly? What if supermarket fish counters came to resemble the cheese aisle at Whole Foods Market, with dozens of varieties available? “I think some consumers would enjoy seeing that kind of diversity,” says Marko. But we’re a long way from that kind of awareness and that kind of transparency.

The diversity lurking beneath familiar labels in today’s supermarkets might even surprise scientists. When Marko’s students sequenced DNA from those 22 fillets sold as red snapper, six of them didn’t correspond to any known species. It raises the possibility that their expedition to the seafood aisle actually turned up something that biologists have yet to discover—a species unknown to science but well known to grocery stores. ❧

Literature Cited
1. Logan, C.A. et al. 2008. An impediment to consumer choice: Overfished species are sold as Pacific red snapper. Biological Conservation (141):1591-1599.
2. Jacquet, J.L. and D. Pauly. 2008. Trade secrets: renaming and mislabeling of seafood. Marine Policy 32(3):309-318.
3. Marko, P.B. et al. 2004. Fisheries: Mislabelling of a depleted reef fish. Nature (430):309-310.
4. Schwartz, J. Fish tale has DNA hook: Students find bad labels. The New York Times, August 21, 2008.



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  • khary anderson February 2, 2010 at 8:10 pm

    Deez fish imposterz! There gonna melt all da icebergs if they not careful!


  • Khary Anderson February 3, 2010 at 9:33 pm

    dang i guess i aint be goin to Red Lobster for my girls bday dis year.


  • WILLIAM B. DUFOUR THE THIRD. July 8, 2010 at 11:20 am



  • apandist October 30, 2011 at 7:45 am

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