(CNN) - If you splurge on the sea bass or snapper, you may not always be getting what you pay for, even at the fanciest restaurants and upscale fish markets.
There's something, well, fishy going on with certain favorite fish dishes, according to a new study from the conservation group Oceana.
DNA tests showed that about 21% of the fish researchers sampled was not what it was called on the label or menu. That's despite nearly a decade of investigations, more regulations and Americans' appetites growing beyond fish sticks and tuna surprise.
"Consumers are getting ripped off," said Beth Lowell, Oceana's deputy vice president. Lowell said this isn't an isolated problem. Her organization tested more than 400 samples from 277 locations in 24 states and in the District of Columbia. Oceana did not name the markets, stores and restaurants where it purchased the samples.
Among the samples they tested, seafood was more frequently mislabeled in restaurants and at smaller markets than in larger grocery chains. One out of three stores and restaurants visited by the investigative team sold at least one mislabeled item.
Favorites like sea bass and snapper had some of the highest rates of mislabeling. Sea bass was mislabeled 55% of the time and snapper 42% of the time, Oceana's tests showed. Often, instead of sea bass, they'd get giant perch or Nile tilapia, fish that should be less expensive and is considered lower quality. Dover sole they tested was actually walleye. Lavender jobfish had been substituted for Florida snapper.
"We've been testing seafood for nine years now, and every time we do a study, we think, 'maybe we will no longer see a problem,' but we keep finding it, and we know it's having an impact on our oceans," Lowell said.
Some of the substituted fish was not sustainably caught, even though it was sold as such, meaning an overfished and endangered Atlantic halibut was sold as the more plentiful Pacific halibut. One in four halibut samples the group tested was mislabeled.
For Americans who are trying to be more mindful about the fish they eat; who are worried about the impact of climate change and endangering fish stock; who want to eat food from lakes or oceans closer to home; or for pregnant women trying to avoid fish with high mercury content, this news has got to be frustrating, Lowell said.
"We need to do more to protect consumers," Lowell said.
Oceana's is not the only recent study to find fish fraud. In December, a New York state Attorney General's Office investigation found that more than one in four samples, or 26.92% of the seafood they bought and tested was mislabeled. In that investigation, the problem was in virtually "every tested seafood category."
New Yorkers who paid 35% extra for "wild" caught would be disappointed to learn that the investigation found it was often farm-raised. The fish substitutes were often cheaper.
"You have to imagine how complex seafood commerce is," said Dan Distel, director and research professor at the Ocean Genome Legacy lab at the Northeastern University Marine Science Center. The lab performed the DNA work in the New York Investigation.
"A lot of mislabeling is probably intentional, sure," he said. "There is also plenty that must be accidental or just the result of the ignorance of the rules."
With so many species and with 80% of the fish Americans eat coming from international sources, labeling is complicated.
"In order to maintain accurate labeling, you have to track it from the fisherman, who is sometimes in remote locations or in the developing world. And then you track it through a variety of middlemen to the distributor, the store, to the high school kids stocking the shelves. There are a lot of places where things could go wrong," Distel said.
Names of fish can also be confusing for people who sell them. Something sold as snapper, for instance, can actually be a few different species. If it's sold as the more expensive red snapper, that's got to be a specific fish, according to FDA rules.
Sometimes, rules even allow a fish to be called something else. Chilean sea bass, for instance, is actually Patagonian toothfish or Antarctic toothfish -- not sea bass. But the restaurant or market has to use "Chilean" in the name. If it's just called "sea bass," it's mislabeled.
"With regard to fraud, honestly, it is fairly simple. Yes, there's a complex global supply chain, like there is for so many products, but the reality is, if something is mislabeled or there's some kind of species substitution, it is fraud plain and simple, and it is just illegal," said Gavin Gibbons with the National Fisheries Institute, an association for the industry. "You would not accept this in any other scenario, and you shouldn't accept it in seafood."
He wishes Oceana would have investigated further to find the source of the mislabeled fish, and he doesn't think the industry needs more regulation. He thinks more of the existing laws should be enforced.
In 2014, the federal government tried to do something about mislabeling, creating the US Government Task Force on Combating Illegal, Unreported and Unregulated Fishing and Seafood Fraud. The task force's recommendations in 2018 created the Seafood Important Monitoring Program, known in the industry as SIMP.
SIMP requires traceability and catch reporting for 13 types of imported seafood considered most at risk for mislabeling, including red snapper, Atlantic cod, grouper, swordfish, tunas, king crab, mahi mahi, sharks and sea cucumber. Oceana wants the government to expand the requirements to all seafood.
Some groups have taken on the issue without waiting for additional regulations.
Demian Willette, an assistant professor of biology at Loyola Marymount University, has worked on an investigation of the mislabeling problem in Los Angeles sushi restaurants. That 2017 investigation found that 47% of the sushi it tested was mislabeled.
He works with the Los Angeles Seafood Monitoring Project team, a group effort that purchases fish from area restaurants, runs DNA tests to see whether it is accurately described and then works with the restaurants and regulators.
"This is not a gotcha operation," Willette said. "We're trying to work with those restaurants to improve this issue."
There are steps consumers can take to get a better chance of eating what you ordered.
Gibbons, of the National Fisheries Institute, suggests asking the fishmonger or your server or chef whether the establishment is a Better Seafood Board member. Members must adhere to industry principles that include correctly labeling products.
Oceana's Lowell also suggests asking your server about where the fish is caught. "Their ability to answer might indicate how much information they have about it," Lowell said.
If you can look the fish in the eye, it can also help. "You up your chances of getting what you order if you buy as close to the whole fish as possible," Lowell said. "The more processing, the more opportunity for a bait and switch."
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