NEW YORK -- Mara's Homemade was "days away" from leasing a space that would have doubled its capacity in New York's East Village, when the restaurant, which sourced 85 percent of its menu from Louisiana, postponed expansion following the worst oil spill in U.S. history.

"I guess I was in denial that oysters wouldn't really be affected, that oil wouldn't get into the marshlands," said David Levi, who purchases the restaurant's ingredients and is married to its owner and namesake.

"People go around the country and say you can't get a bagel like you can in New York, and that's true. You can't get food like you can in south Louisiana," Levi said.

The Louisiana seafood industry has been hit hard since a rig operated by BP Plc exploded April 20 in the Gulf of Mexico. The spill has washed ashore in four states.

Mara's is trying to compensate for shortages of gulf oysters and shrimp with new menu items, like cafe au lait and a Cajun-style hamburger seasoned with the same marinade the restaurant uses for alligator dishes. Mara's is considering filing a claim for damages with BP.

Mara's estimates it is losing about $3,000 to $4,000 a week on canceled menu items and tighter margins.

"Just oysters alone, it's over $1,000," Levi said. "Margins are going crazy."

Gulf Coast sales accounted for about $639 million of the $3.85 billion U.S. market for seafood as of 2008, according to the National Oceanic and Atmospheric Administration. In pounds, the haul accounts for one-quarter of the U.S. catch, excluding Alaska and Hawaii.

Brasserie, in midtown Manhattan, has replaced gulf shrimp with those from Thailand.

"It's a very good product and comparable in flavor and size," said David Pogrebin, general manager of Brasserie. "We're paying close attention to what's happening in the Gulf of Mexico."

While prices for gulf products may be rising, overall seafood costs have fallen, said Eric Ripert, chef of Le Bernardin in Midtown. Le Bernardin mostly uses fish from North Atlantic waters aside from gulf red snapper and hasn't had to change its menu because of the spill.

"I think the snapper is a great fish," Ripert said. "We never prioritize the price, we prioritize the quality."

Louisiana is the largest U.S. oyster producer, with as much as 40 percent of the domestic crop, and contributes $318 million to the state economy, according to the state's Department of Wildlife and Fisheries.

Mara's bought most of its oysters from New Orleans-based P&J Oysters, the oldest continually operating oyster dealer in the U.S. according to its Web site. P&J, located in the French Quarter, sold about 70,000 oysters a day and shucked about 30,000 before the spill, and it is now experimenting with distributing preshucked oysters from the West Coast, said Sal Sunseri, co-owner and vice president of P&J.

"So far it's been a negative response," Sunseri said. "It's not the same quality, texture or flavor."

The company, which plans to file a claim with BP, now sells about 20,000 oysters a day and expects that amount to decline, he said.

After its oyster supply was cut short following the spill, Mara's started buying Delaware oysters at Fulton Fish Market in the Bronx and is using increased traffic from the World Cup to serve lunch again, hoping to make up for narrower margins, Levi said.

"In the restaurant business, it's not what you sell it for, it's where you go to buy it," Levi said.