Something fishy going on in U.S. seafood market?

Think you're eating red snapper? According to a new report, it actually might be a fish of a different color entirely.

The non-profit advocacy group Oceana says nearly one-in-three fish we eat is mislabeled. "Early Show" Special Contributor Katie Lee explained it's called "fish fraud." That means when you go to your favorite restaurant, grocery store or seafood market, your fish might be something else altogether.

Seafood you eat may not be what you think it is

So what could be going on?

Lee said with a head and tail, you know what you're buying, but with fish filets, it's tougher to tell.

According to Oceana, fish are often replaced with cheaper species. Oceana's report says cod is often oilfish. Wild salmon, they say, could be straight from the farm. And red snapper is something different like tilapia more than 70 percent of the time.

Margot Stiles, a marine biologist with Oceana, told Lee more than 80 percent of the fish Americans eat is brought in from overseas. Stiles added only two percent of that is inspected by the Food and Drug Administration.

Lee reported much of that imported fish arrives already processed, filleted and frozen. So companies like U.S. Foodservice, one of the largest seafood buyers in the country, has their fish DNA tested before they sell it.

They send samples of their seafood to a lab in Florida where the type of fish is confirmed.

LeeAnn Applewhite, chief executive officer of Applied Food Technologies, said, "It's like the CSI of the seafood industry."

Jorge Hernandez, of U.S. Foodservice, said food testing ensures that the product they're selling is the product they say they're selling.

For those of us who aren't scientists, there are some things you can do.

Lee asked, "Whole fish, is this the best way to know you're getting what you paid for?"

Oceana's Stiles said, "It is. Ideally, you can look at the fish and clearly see this is a red snapper."

Lee asked, "So I should just take this and ask my fish monger to cut it up for dinner for me?"

Stiles said, "That would be great, and then right in front of your eyes you know you're getting what you paid for."

But for fish fans, it's not a perfect solution.

One woman told CBS News, "It's a catch-22, are you going to pay for a filet, or are you going to pay more for a fish to see what it is and not eat all of it anyway."

On "The Early Show," co-anchor Chris Wragge remarked that this isn't just an issue of fraud, but a health issue, too.

Lee said, "That's right, it's not just about your wallet. Imagine if you are allergic to a certain type of seafood and it ends up on your plate. You have to make sure you getting what is advertised. And ask questions."