Plan to raise Some enterprising scientists and investors believe the Gulf of Mexico might have a bright future as the nation's largest fish farm, thanks partly to research conducted in Hawaii.
fish in cages rattles
some scientists
Gulf coast consortium looks to
technique tested in Hawaii
to boost seafood takeBy Ben Raines
Newhouse News ServiceThey say the Gulf, which naturally produces $775 million worth of seafood a year, could generate millions more if the federal government would allow the aquaculture industry to raise red snapper, cobia and other species in giant underwater cages in the open waters.
The controversial technique has been used around the world with great success -- though sometimes at great cost to the local environment.
The Mississippi/Alabama Sea Grant Consortium is conducting a federally funded aquaculture experiment 20 miles south of Pascagoula, Miss., near a Chevron oil rig. The fish will be hand-fed, then harvested from the cages and sold at market without ever swimming free in the Gulf -- and without ever tightening a fisherman's line or filling a commercial boat's nets.
A similar experiment by Hawaii's Sea Grant lab led to the approval of a commercial offshore aquaculture enterprise just two years after the lab began raising fish offshore. On the Gulf, there is at least one commercial operator ready to start production if permits become available.
Learning from the Hawaii example, the Mississippi researchers believe that simply moving the cages from shallow inshore waters to deeper water offshore will protect the Gulf from a lot of the problems linked to aquaculture. Strong offshore ocean currents, they say, will sweep away waste products and keep the water around the fish more pure, lessening the risk of disease.
They hope the deeper, cleaner water also will eliminate the need for the massive doses of antibiotics often used in salmon farming. Health officials say overuse of antibiotics in both humans and farm operations may have helped produce drug-resistant disease strains. Given that, some say it is unlikely that the government would approve widespread use of antibiotics in the open Gulf.
"In a nutshell, we didn't see any negative environmental impact," said Charles Helsley, who headed the Hawaii experiment.
His group started a batch of fish -- moi, also known as Pacific threadfin -- in the spring of 2000. By the fall of that year, they raised 90,000 pounds of fish, worth about $450,000.
Helsley's team monitored the sea floor under the cage for accumulations of food or waste that might harm water quality. They also surveyed the surrounding waters. Excess food didn't appear to be a problem as the huge cage attracted about 10,000 wild fish that gobbled any leftovers. Helsley detected only a stream of ammonia -- a basic component of fish waste -- coming from the cage. The stream was not detectable 1,000 feet away.
While the program was commercially viable in the Pacific, Helsley said the Gulf will pose new challenges, including rougher seas, shallower water and potential conflict with the high number of recreational fishermen.
The Hawaiian effort was directed in 150 feet of water, but the Gulf experiments are being conducted in water that is only about 80 feet deep. And Gulf researchers had to travel at least 20 miles offshore to find water that deep, while Hawaiian researchers could set up their deepwater operation only a mile from the beach in Ewa.
So far, the Gulf itself is the only thing slowing down the Sea Grant experiment. Shortly after the $100,000 cage was deployed, a December storm ripped the entire structure from its 27,000-pound concrete anchor. The cage disappeared into the depths. While there were no fish in the cage at the time, the loss was a major setback, especially in the eyes of federal regulators, already worried about the impact of escaped hatchery fish on native species.
The cage, provided by the Ocean Spar company, was found weeks later, washed up on the Chandeleur Islands off Louisiana's east coast, miles from where it was anchored.
Chris Bridger with Mississippi/Alabama Sea Grant said the recovered cage will be redeployed offshore in a few months, this time with four anchors instead of one and 10,000 fingerling-size redfish.
The ultimate goal of the program is to grow red snapper, but Bridger said no American hatcheries are producing enough baby snapper to stock the cage.
Proponents say the farming would take nothing from the Gulf and do no harm to its waters while providing jobs and making seafood more affordable. They believe it also will lessen fishing pressure on sought-after species such as grouper and red snapper, now so heavily fished that they are protected with closed seasons and strict limits.