In a new report, the environmental nonprofit organization Oceana sought to determine just how much of the wild salmon sold at grocery stores and restaurants is actually legit. And the findings are pretty infuriating. After testing the DNA of 82 varieties of salmon labeled as “wild” in cities including New York, Chicago, and Washington DC, Oceana determined that 43% of these samples were mislabeled. MORE: The Secret to Perfectly Baked Salmon This isn’t the first time Oceana has investigated our salmon supply. But its last report, published in 2013, found that only 7% of wild salmon was mislabeled. So what changed since then? Sure, the fact that the wild stuff is more popular than ever might tempt more purveyors into duping you and pocketing the profit. But there’s more to it. “The majority of our sampling of salmon in 2013 was in the summer, during the commercial fishing season,” explains Beth Lowell, senior campaign director at Oceana. But this new report tested salmon samples during the winter, when wild salmon isn’t really in season. It might not be surprising, then, that wild salmon fraud seems to skyrocket during the colder months, when the fish is harder to get. “It’s not like it was a clerical error. At the level we found, it’s clear that someone is doing this intentionally,” Lowell says. MORE: The 10 Healthiest Fish on the Planet So how can you tell whether the salmon you’re buying is actually wild, and not the farmed stuff that’s pumped up with antibiotics, corn, and soy? For starters, don’t rely on how the fish looks—even if you think you’re really savvy. “We’ve done side-by-side displays [with wild and farmed salmon] and it’s tough to tell just by looking at it, even for fish experts,” Lowell says. Instead, consider these three rules of thumb, especially in the winter: • Look for specifics. The more information that’s available, the less of a chance that your wild salmon is a fake. For instance, salmon labeled as Chinook or King is more likely to be the real deal than just “salmon” or “wild salmon,” Lowell explains. But if the label doesn’t specify…• Don’t be afraid to ask questions. Specifically, “Where was this fish caught?” The answer you’re looking for is somewhere in the Pacific Ocean. “If they can’t tell you or it doesn’t seem like it adds up, pick something else,” Lowell says. And if all else fails…• Consider the cost. Wild salmon isn’t cheap. So if the price seems too good to be true, it probably is. Sorry!