(WASHINGTON) -- Take a close look at that fish you buy from the grocery store or the sushi you order from a restaurant. It might not be what you think it is.
The conservation group Oceana recently sampled 96 supermarkets, restaurants, and sushi venues in South Florida and found that 31 percent of the time, the fish you order or buy is mislabeled. For instance, when you order or buy snapper, you'll sometimes get tilapia because it’s a cheaper variety.
“Most of our mislabeling was, I would presume for economic reasons, where you would get a farmed product being sold as a wild species,” said Oceana's Kimberly Warner.
One of the worst problems, she says, was with white tuna; it was mislabeled at every single one of the sushi restaurants researchers looked at -- and the fish that was on the plate instead, it turns out, can make you sick.
“Everything that was labeled white tuna was actually this escolar species, and it's a fish that the FDA warns people not to eat because of this naturally occurring toxin that it has,” Warner said.
She advises consumers to ask where the fish they're buying was caught, how it was caught, and what kind it is. And just like when it comes to the rest of our food, many believe that more regulation is needed.
“Ultimately, the solution is going to be a full traceability system for our seafood,” Warner said. “Right now, it's really hard to tell where on this very murky supply chain the fish fraud is occurring.”
Copyright 2012 ABC News Radio