Long John Silver's is on a crusade to get consumers to "Think fish."

The chain is planning a major brand relaunch this year, starting with a new campaign this week with a new tagline, "Think fish," that includes TV spots with environmental messaging. In one spot dubbed "Final frontier," a voiceover narrates, "Anyone ever heard of free range?" with imagery of confined cows. The voiceover next says, "Get your next meal from the real frontier -- fish sustainably harvested from the wildest place on earth."

The spots were created by Louisville, Ky. agency Creative Alliance, and the campaign will also include national print coupon insertions in Sunday newspapers, online ads, social media and direct-to-consumer communication in restaurants.

The three TV spots, "Methane," "Marinated Pork" and "Final Frontier," will air on cable networks like Discovery, HGTV, The Weather Channel, TNT, ESPN2, USA Network and TBS. The company said more ads are in production. The campaign also comes at a time of year -- before Lent -- when other fast food chains typically promote their fish dishes more than usual.

Of course, overfishing is a major concern and is considered by some sustainability experts as detrimental as industrialized farming, but Long John Silver's said it sources fish responsibly.

The chain "sources its core fish (filets, sandwiches) from the North Pacific and only from suppliers who use certified, sustainable fisheries," said a spokesman in an email. The chain also sells shrimp and other types of seafood such as lobster for Lobster Bites (which are being reintroduced for a limited time in February). Non-core items such as shrimp are farmed, but the lobster for the Lobster Bites is wild-caught, according to the spokesman.

"Over the last two years, we've been evolving our menu and communications to contemporize the brand and make it more relevant for how consumers eat today," said Charles St. Clair, chief marketing officer, in a statement. "These new ads are designed to help consumers understand that something new is happening at Long John Silver's," he said, adding that the chain has introduced more non-fried entrees like the Zesty Asian or Creamy Garlic Baked Cod and Shrimp, along with more portable items like the Ciabatta Jack Fish Sandwich and our new Dippin' Fish Strips for on-the-go customers."

The chain, along with most other fast-food chains, had been under pressure for offering fatty food. Long John Silver's in August said it would eliminate trans fat by the end of 2013, after Center for Science in the Public Interest publicized that the chain's Big Catch plate was "the worst restaurant meal in America," with a staggering 33 grams of trans fat.

Last year the chain also unveiled a menu on its website featuring meals under 600 calories.

"We offer a variety of seafood choices including baked cod and baked shrimp to satisfy a broad range of consumer taste options from indulgent to lighter tasting," said Mr. St. Clair in the statement. "The experts agree: Americans should eat more seafood and we're making it easy to do that."

Long John Silvers is the largest seafood chain in the U.S. It had $615 million in U.S. systemwide sales in 2012, down 3.1% from 2011. It was sold by Yum Brands in 2011 and in January 2012, launched what it called its biggest menu overhaul in a decade that included bigger shrimp and non-fried options.