(July 19, 2010)—Laurentino Cardenas leaned over the edge of his narrow boat, his hands clenched above the murky, green surface of the Gulf of Mexico's Bayou Terrebonne. The name means "good earth" in French, and it indeed has been good to Louisiana.

Oystermen long have scraped the Gulf's floor, clinging to metal rakes as oysters cling to reefs, with a determination that has allowed them to survive nature's wrath and man's mistakes. Until now.

The BP oil spill is killing off a centuries-old way of life, and endangering one of the world's largest wild-oyster systems. Businesses nationwide have been hurt or destroyed because Cardenas and his peers can't work. Along the way, the oyster has become a barometer of the oil spill's economic reach and a portent of long-term effects.

Louisiana's 1.6 million acres of public oyster beds, and more than half of its 400,000 privately leased acres, are off-limits. Hundreds of oystermen have stopped fishing. Processors have shut down. Gulf restaurants have closed, and chains such as Red Lobster have yanked the briny morsels off their menus. What supplies remain have more than doubled in price, with some restaurateurs paying $200 for a 150-count case.

That's only the beginning. Scientists fear generations of larvae and mollusks could be wiped out, destroying harvests for years. The cruelest twist: Oyster beds that survived the now-capped gusher could be leveled by the cleanup efforts.

After the Deepwater Horizon rig explosion April 20, Louisiana officials decided to use Mississippi River water to push back encroaching oil. Culverts built into the river's levee system were opened, redirecting freshwater into saltwater estuaries. The resulting change in salinity can be fatal to the mollusks.

State scientists started checking beds two weeks ago. Their early findings: a wide spread of dead oysters.

"There's a lot of talk that this is killing off the Gulf oyster industry, that after [Hurricane] Katrina and this, it's the end," said Bill Sieleg, who heads a Maryland-based oyster trade group.

European treat

Oysters are a $1 billion domestic industry and a culinary aberration: Most seafood that Americans eat is imported. But oysters, with their heavy shells, are expensive to ship by air. They're also considered best eaten fresh, not frozen. So the majority of oysters we eat come from U.S. coasts, two-thirds of which are trucked from warm Gulf waters.

Oysters long were a European treat for the rich. But it was in Louisiana where this simple bivalve — mild in flavor and traditionally cheap enough for almost anyone to buy a platter — was reclaimed as the Everyman mollusk. Grocers across the country stocked mounds of Crassostrea virginica, allowing cooks to whip up oyster dressing at Thanksgiving.

The oyster is to Louisiana what corn is to Iowa or oranges to Florida — part sustenance, part identity. The ingenuity of the region's chefs turned out oyster fritters, oysters Bienville and oyster po'boys. They gave birth to oysters Rockefeller, reportedly named after oil baron John D. Rockefeller — the only thing richer than the sauce.

So the loss strikes like a bomb in this state.

"Oysters are part of everyone's upbringing. It's family history," said Susan Spicer, a prominent New Orleans chef who is suing BP for the loss of local seafood supplies. "It's unthinkable, a future without them."

At Felix's Restaurant & Oyster Bar, on a brick-lined stretch of the French Quarter in New Orleans, the menu proclaimed that it "only serves LOUISIANA oysters." Owner John Rotonti can't bring himself to print a correction; homegrown oysters were the heart of his business. He wrestled with a disquieting truth: Felix's slowly was changing from a Gulf restaurant into one that's simply on the Gulf.

"It's like part of the restaurant is gone," he said.

Rotonti is using Texas and Florida oysters. His manager called Connecticut to do the unthinkable: Buy Blue Point oysters from the cold waters of the Atlantic — iconic of New England chowder and the Kennedys, not of Creole spice and the soft drawl of the Deep South.

But he may not get them. Many farmers elsewhere have sold their harvests. There are also fewer to buy. It's not clear why, but the ocean waters off Washington state and Oregon are changing: As much as 60 percent of larvae in area hatcheries have died in recent years. On the East Coast, in Chesapeake Bay, beds are recovering from overfishing, disease and pollution.

Americans willing to settle for smoked or canned oysters are in luck. Asian firms, which dominate that market, assure that holiday supplies will be plentiful.

But few foreign companies meet the Food and Drug Administration's strict water-testing requirements that would allow them to sell live oysters in the United States. Meanwhile, prospects of domestic production expanding soon are dim. Regulation of coastal management is strict. Land is scarce. It can take up to four years for an oyster to grow big enough to sell.

Their value isn't just monetary. Oysters help filter the ocean. Their shells shelter other sea life. Their meat feeds snapper, black sea bass and other creatures. They are "the fabric that everything else builds upon," said Michael Blum, an assistant professor of ecology and evolutionary biology at Tulane University in New Orleans.

Economic ripples

State and federal officials started closing oyster beds April 29, and economic ripples were felt far and wide. Oysterman Cardenas and his peers were among the first to hurt.

Born in Querétaro, a landlocked stretch of central Mexico, Cardenas never was enrolled in school. As a teen, he heard a woman gossip about fortunes being made in the Gulf in oysters. So Cardenas sneaked across the border in 1980. He arrived at the fishing town of Houma, La., 57 miles southwest of New Orleans. He was 14.

He married, became a citizen and bought a little white house. Not the riches he heard about as a child. But enough.

Now, unable to pay bills with fishing, Cardenas and other out-of-work oystermen tried to land jobs with BP to clean the Gulf. Out-of-state vessels vied for the $1,200 to $3,000 daily pay. Some were lucky. Not Cardenas. He passes time playing checkers.

But oystermen weren't the only ones affected.

Sales are evaporating at Natural Fibre Products in New Orleans, which sold the burlap bags that transported Cardenas' 100-pound loads from boat to box. Two employees have been laid off; one ekes out 15 hours a week.

At Allen-Bailey Tag & Label in Caledonia, N.Y., which made the shellfish tags affixed to each bag, sales have sagged. On top of that, the firm found out in June that it had won a bid it made before the oil spill to sell as many as 7.8 million tags in Louisiana. Tens of thousands of dollars now could be lost.

Broken shells were sold to Steve Ortego, whose Houma firm used the shards in road projects. Layered under limestone, they kept wet soil from seeping through. Two of his vendors have shut down. The other two struggle to stay open.

Cardenas sold his catch to Mike and Steve Voisin, owners of Motivatit Seafoods in Houma. Their forefathers, who emigrated from France on the eve of the American Revolution, plucked seafood from the Gulf. Before the oil spill, the Voisins' two processing plants employed 200 and handled about 360,000 oysters daily.

Inside the plants, oysters clattered on conveyor belts. They were washed and run through a pressurized system to kill bacteria. The belts don't run as often now. Workers handle 92 percent fewer oysters and scrape by on 30-hour weeks.

In a place where people see many things as God's will, the Voisins turned to their faith. Mike prayed. Steve kept his Bible in the office and read five to six chapters daily. They assured people these dark times were temporary. The beds, they said, were fine.

At home, the brothers wondered whether they were next to closing.

As of July, six major oyster processors in Louisiana and Mississippi had closed, including P&J Oyster in New Orleans. P&J survived the Depression and Katrina, but not this.

As Gulf oyster supplies faded, panic rippled across the nation's maritime food chain. Bill Guerra paced a sidewalk one morning, waiting for a Motivatit delivery. The haggard general manager of King Oyster, a seafood distributor in downtown Los Angeles, resembled a defeated boxer.

He handled 5,000 cases weekly last year. In May: 300. In June: 15.

"This is going to put me out of business," Guerra said.

Lisa Halili's Prestige Oysters in San Leon, Texas, is one of the largest private leaseholders of oyster beds. Hurricane Ike doused them with sediment in 2008. Hermit crabs also have swiped meat. "It's like locusts come in and take over a farmer's crop," said Halili, who's running low again.

And 1,400 miles to the west, in Pomona, Calif., restaurant manager Omar Quezada started placing orders for oysters from the Pacific. In the kitchen of El 7 Mares, there were three cases of oysters: one from Motivatit, two from Baja California. The mollusks from Mexico were bigger, saltier and had a black ring circling the dense meat.

The price had increased, but they were available and met federal regulations. Quezada wondered whether Gulf oysters would ever return. There were media reports of oil found in blue-crab larvae from Louisiana to Florida. Crabs can move. Oysters can't.

His customers wanted oysters. Yet for the first time, they feared eating seafood from the Gulf of Mexico.