A new report from the Food and Agriculture Organization of the United Nations (FAO) finds that fish fraud remains widespread in markets around the world, with studies suggesting roughly 20 percent of the $195 billion global fisheries and aquaculture trade may be subject to some form of deception.

The report, “Food fraud in the fisheries and aquaculture sector,” was produced by FAO’s Fisheries and Aquaculture Division in cooperation with the Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture. While there is no official global baseline, FAO notes that seafood fraud appears to occur at higher rates than in meat or produce sectors, in part because more than 12,000 seafood species are traded worldwide.

The report defines fish fraud as “a deliberate practice intended to deceive others” and outlines a wide range of schemes. These include species substitutions such as selling tilapia as red snapper, or mislabeling of origin of sustainability claims, adulteration like adding coloring to tuna, and counterfeit products, including imitation shrimp made from starch-based compounds. Some fraud also involved disguising over-quota landings or masking geographic origin, posing potential risks to stock sustainability.

Actual studies cited in the report suggest that up to 30 percent of seafood products may be mislabeled in restaurants. In the United States, FAO notes that as much as a third of aquatic products sold may not match what is listed on the packaging, while less than 1 percent of imports are tested.

Economic incentives are a primary driver. Selling farmed Atlantic salmon as wild Pacific salmon can generate nearly $10 more per kilogram, according to the report. Farmed seabass marketed as local to Italy sells for two to three times as much as the sam fish originating from Greece or Turkey.

To combat fraud, FAO advocates harmonized labeling requirements, mandatory inclusion of scientific names where possible, and improved traceability systems. The report highlights analytical tools, including DNA barcoding, stable isotope analysis, nuclear magnetic resonance, enzyme-linked immunosorbent assays, portable X-ray fluorescence, and machine-learning models, to verify species and origin.

In the U.S., SeaD Consulting, a specialized third-party food-testing firm that combats seafood fraud in the Gulf region, uses a tool called the RIGHTest to conduct genetic testing on shrimp served at restaurants and festivals. They have shown that many restaurants have indicated, either verbally or on the menu, that they serve domestic, wild-caught shrimp, when in fact they serve imported shrimp.