GCRL harvests first shrimp since Katrina

By VETO F. ROLEY
OCEAN SPRINGS -- University of Southern Mississippi marine aquaculture scientists working at Cedar Point facilities harvested their first shrimp since Hurricane Katrina struck the Gulf Coast.
The shrimp were raised at Southern Mississippi's Gulf Coast Research Laboratory facility at Cedar Point. Dr. Jeff Lotz, director of the Marine Aquaculture Program at the GCRL, said the one-acre facility is a research and demonstration project.
Since shrimp are grown in commercial-size tanks at the GCRL facility, Lotz said scientists are able to conduct experiments on the shrimp at a level seen in commercial fisheries. Many times, he said, experiments performed at smaller facilities did not fully reproduce at larger facilities.
Tuesday's harvest is such an experiment, as GCRL officials harvested two tanks in the 12-tank facility. One tank was filled to capacity with water and the other tank was filled to half capacity. With the experiments, officials at the GCRL are able to see how the shrimp grow in different conditions.
More than being an academic site, Lotz said the GCRL is also a demonstration project, meaning that officials hope that technology created at the site can be used by aquaculture farmers across Mississippi and the nation.
Dr. Tom McIlwain said the goal of the program is to show farmers how they could vary their crop program by adding shrimp or other fish to the rotation.
" Raising row crops and raising livestock is different," McIlwain said. "And, there is a difference between livestock and aquaculture. But, all three involve animal husbandry."
As aquaculture develops, McIlwain said he could see farmers with limited space, such as a farmer raising crops on 40 acres of land, being able to get a lot more value off their land.
Lotz noted that a facility like the GCRL could produce 150,000 pounds of shrimp a year. The typical pond-based shrimp farm, Lotz said, produced about 4,000-to-6,000 pounds per acre.
Part of the reason for the increased yield at a facility like the GCRL, Lotz said, is temperature. Since an indoor commercial facility can control the temperature, GCRL-type facilities can grow shrimp year-round, producing three harvests a year rather than one harvest a year at most pond-based shrimp farms.
Increased yields are also made possible because of better water usage. Where pond-raised farms use 250 or more gallons of water to raise a pound of shrimp, GCRL-type facilities can raise a pound of shrimp in 20 gallons of water.
Since the water within the tanks are pumped into a retention pond at GCRL-type facilities and then pumped back into the shrimp tanks, Lotz said waster water was rarely discharged into sewage systems.
"It is environmentally friendly," said Lotz. "Water is a valuable resource, and facilities like this keep water waste low."
Water from the shrimp tanks inside the building is pumped out to a retention pond. There waste from the shrimp settles to the bottom. McIlwain said the waste, once removed from the pond and dried out, had value. The waste, which is rich in nitrogen and nitrates, can be used for fertilizer on crops or burned for energy.
McIlwain noted that commercially produced saltwater shrimp could be grown in water that had as little as two parts salt per 1,000 parts water, which is below the tastible amount of three parts salt per 1,000 parts water. Seawater, such as the Gulf of Mexico, has 30-to-32 parts salt per 1,000 parts water.
The ability to grow shrimp in low-salt water meant that growers might not have to remove the salt before using the solid waste from the facility as fertilizer, said McIlwain.
Another benefit of GCRL-like facilities is size. McIlwain said farmers could convert old chicken houses or other facilities to grow shrimp on small ground plots.
" Farmers know how to put things together inexpensively," said McIlwain, who said a farmer might be able to develop a shrimp farm for around $200,000.
Further, said Lotz, a GCRL-type farm could be put into abandoned big-box stores such as former grocery stores or large general stores. "Because of the technology involved," said Lotz, "the initial cost is a little higher. But, the idea is for farming."
GCRL-like facilities could be put in operation nation-wide, said McIlwain, allowing truly fresh seafood to be served any where in the nation. Much like lobsters are viewed live today by restaurant customers, McIlwain said shrimp, and other fish, could be harvested from a GCRL-like facility in the morning, transported live to restaurants and put in live tanks by restaurants for customers to choose.
"That is the way it is done in Asia," McIlwain said, who said customers in Asia are able to enter the restaurant and pick their dinner swimming in an aquarium. "You know that it is fresh," he said.
Lotz said facility-raised fish allowed customers to know what they are eating, since diet and conditions could be controlled, unlike shrimp in the wild. "The shrimp are very healthy to eat," said Lotz.
Further, McIlwain said commercial fisheries are the wave of the future.
"Wild-captured fish basically peaked out 10 to 15 years ago," said McIlwain. "Today, we catch about as much fish in the wild as we did 20 years ago."
While the harvest levels for fish captured in open seas has remained the same, demand has continued to go up. Today, McIlwain says U.S. consumers eat about one billion pounds of shrimp a year.
"While the wild harvest will still have a major roll to play in supplying demand, we are not going to produce any more from the wild areas then we currently do," McIlwain said.
Because wild harvest is peaked, suppliers will have to turn to commercial, land-based operations. McIlwain said GCRL-like facilities will play an important roll in the future.
"I see aquaculture developing like chicken farming," said McIlwain.
Sixty years ago, he said, free-range chicken was the model for poultry production. Today, the process is much more manufactured. One farmer hatches eggs and another raises hatchlings to production size.
"Fifty years from now," said McIlwain, "we will look at facilities like this as being crude in producing fish."

Source:
The Mississippi Press