Unless you're a fisherman (or -woman) who really knows fish species, it's difficult to fight fish fraud. Still, there are some steps you can take. Whenever possible, purchase a whole fish — fins, head and tail still attached. It's a lot more difficult for swindlers to substitute another fish for the one you're seeking when you can see exactly what the fish you're buying looks like. (Of course, this assumes you know what a red snapper or Chilean sea bass looks like, so bone up on that in advance.) Whether you're dining in a restaurant or browsing a fish market, ask lots of questions. Ask if a particular fish was wild- or farm-raised, where it was raised, or when and how it was caught. If the seller doesn't know or hedges, be suspicious [source: Oceana].
The FDA also maintains a list of acceptable market names for seafood. If you spot a fish labeled with a name that's not on the FDA's list, such as "white tuna," you can pretty much be assured that the fish is actually another species. Vet your fish retailer with the Better Seafood Board. Perhaps the easiest way to fight fraud, though, is to be wary of a quality fish carrying a low price. Sockeye salmon, for example, is not cheap. So if you're ordering or purchasing Sockeye salmon for a bargain-basement price, it's probably farmed Atlantic salmon or something else [sources: Goetz, Lou].
Lest you think the onus of fish fraud is only on consumers, it's not. While some complain the U.S. government isn't doing enough to fight fish fraud, a presidential task force made several recommendations on the topic in December 2015. One was for better international cooperation and collaboration on seafood labeling. Oceana is pushing for an international traceability system. The idea is that fish retailers would be required to know where and when a fish was caught, and even what gear was used, and would also be required to pass this info to consumers [sources: Lou, Barclay]
Scientists at the University of South Florida's College of Marine Science recently unveiled Groupercheck, a portable, handheld sensor that can identify grouper in 45 minutes, using DNA markers only found on real groupers. The device can be used by anyone from distributors to restaurateurs; the scientists hope to unveil similar devices for red snapper, shrimp, tuna and halibut [source: Trigaux].
Now that more attention is being focused on fish fraud, hopefully the practice will soon be on the wane.