• Although aquaculture is billed as a clean industry, pollution from waste water fouled by food, medicine and fish excrement is a threat to sensitive coastal areas.
• A lot of fish in a small area increases the possibility of disease sweeping through the farm and possibly contaminating natural stocks.
• In a headlong rush to exploit resources for cash, many developing countries have allowed fish farms to displace natural fish habitats in wetlands and mangrove forests, causing permanent environmental damage and ruining agricultural areas.
• Start-up costs for some aquaculture operations can be daunting — as much as $4,000 per acre in the United States to create a catfish pond, not counting the land, and operators must wait as long as 18 months for the fish to mature to a marketable size. Also, fish farmers face the same weather and market forces that have threatened disaster for traditional farmers for thousands of years.

Clark Lee carefully manuevers his pirogue from one mesh pen to another. Besides bass, Lafourche Mariculture raises the only farm-produced redfish in Louisiana.

Work and worry
  Wearing jeans and cotton shirts under coveralls, Fernandez and his employees — mostly fishers working there between seasons — scoop dog-food-like pellets from 100-pound bags and throw them across the top of the cages and basins.
  The water froths up like the Amazon in a piranha movie – tails, fins and mouths flashing on the surface.
  On harvest days, the workers don wet suits to corral fish into nets and then into refrigerated trucks for the trip to market.
  Despite his use of modern technology, Fernandez is as much at the mercy of the weather, market prices and plagues as an 1800s sodbuster or a modern-day fisher.
  He’s had an entire crop killed by freezing weather and another washed away by high tides after Hurricane Gilbert. Two other farms, in Grand Isle and Dulac, were wiped out by the hurricane.
  Fernandez guards against plagues by scooping up fish from holding ponds and vaccinating each one against pastorella, a bacterial disease that can wipe out a fish farm in two weeks.
  Fernandez also must traverse a myriad of state and federal regulations before any of his fish can be sold to New Orleans restaurants. His operations are subject to unannounced inspections by federal and state health and wildlife officials and he must keep ‘‘cradle-to-grave’’ paperwork proving each young fish came from an approved hatchery and not the wild.   Through it all, Fernandez is fighting an uphill battle to keep his fish at a price competitive with those caught in the wild.
  The biggest expense, Fernandez said, is the feed developed for redfish and bass of fish. About 40 percent of the material in the pellets is menhaden fish meal, which is mixed with soybean and corn. Fernandez said the fish gain 1 pound for every 2 pounds of feed.
  Until he is able to develop a steady market for the fish, he will be at the whim of market forces. The recent partial ban on gill net fishing in Louisiana waters will help push prices up, but Latin American investors are looking into their own caged redfish operations, which could operate with fewer regulations and lower-paid workers.
  Aquaculture has become a significant cash crop for developing countries, especially the production of shrimp, and often at the expense of fishers and the poor. The farms are bankrolled by foreign investors who keep the profit and ship the fish off to the highest bidders.
  The shrimp are too expensive for native populations. And the farms hire at most a handful of native workers.
  Unfortunately, during the first two decades of the aquaculture boom, the shrimp farms themselves often have been short-lived, according to the United Nations and aquaculture researchers.
  They often are operated as intensive, environmentally degrading businesses that must be abandoned in only a few years, after the investors earn their money back.
  Often what’s left behind is a devastated habitat that once was the nursery for native shrimp and fish, food and cash crop for local people.
  In Ecuador, for example, about 20 percent of the country’s coastal mangrove forests had been destroyed by aquaculture operations by the late 1980s, said Conner Bailey, a fishery development specialist at Auburn University.
  Ecuadorean officials blame the destruction for a dramatic drop in the populations of several wild fisheries.
  That is why Louisiana, a nursery for an incredible bounty of wild fish, could be left out in the rush to farm fish.
  ‘‘You’ll probably never see the expansive shrimp farms in Louisiana of the type that exist in South Carolina or Texas or various tropical countries simply because of the restrictions on coastal land use here,’’ Lutz said.
  ‘‘To be successful here, you’d have to see the same conditions as have destroyed the coastline of Thailand, and even then, they wouldn’t be able to compete because the cost of production would be higher here because you’d be limited to one short growing season.’’
  But growing populations and declining ocean harvests are likely to make fish farming more and more economically attractive.
  What is driving the few operations like Lafourche Mariculture to continue experimenting is marsh landowners’ concern that their traditional sources of revenue — oil and gas and the muskrat and nutria fur industries — are drying up.
  ‘‘Our company, with the decline in oil and gas, had all this land with water on it,’’ Fernandez said. ‘‘They brought me over from Texas and asked, ‘What can we do with it?’ "