Aquaculture May Relieve Problem Of Fished-Out Oceans

June 17, 1999

GAINESVILLE — As more people are turning to fish for a health-conscious food staple, aquaculture could stave off the threat of fished-out oceans in the next 40 years, say University of Florida researchers.

The consumer market for seafood is skyrocketing. With global waters already being harvested to capacity, meeting the demand for food fish will become an increasing challenge.

“The amount of fish available for consumption worldwide has really not grown,” said Jim Cato, director of Florida Sea Grant College at UF. “In fact, about 66 percent of the world’s fisheries are overfished, in a stable state of production or declining.”

Over the last decade, according to Cato, per capita consumption of seafood in the United States has doubled, while in Florida the size of the total fish catch has decreased by about 20 percent. The total value of the Florida catch has increased about 10 percent, with consumers paying more for a smaller amount of fish.

Frank Chapman, fisheries and aquatic science specialist at UF’s Institute of Food and Agricultural Sciences, says declining fisheries are the result of overfishing and laissez-faire fishery management. “The bottom line is that we can only get so much fish out of a given body of water,” he said. “When one type of fish becomes scarce, a new species enters a fishery.”

The result can be the exhaustion of a particular species before it has time to replenish its stocks. Chapman researches the growth traits and reproduction capabilities of sturgeon, a species he says is nearly extinct in Florida, because it takes 30 years to reach sexual maturity.

The orange roughy is headed in the same direction. Discovered by trendy restaurants in the mid- 80s, this New Zealand white fish is on the cusp of endangered status. “In ten years, they’re done,” he said. “This happens over and over and over.”

Aquaculture — or fish-farming — will play an increasingly important role in both conserving existing wild stocks and producing more food fish, says Chapman.

“As the population increases, we’re going to put even more pressure on our food resources. Either we’re going to have to stop eating seafood — which is highly unlikely — or we find a way to make up for that difference. A viable alternative is aquaculture,” he said.

“If an acre of water will hold 1,000 pounds of fish, in an aquaculture pond we can produce 4,000 pounds of fish,” says Chapman. “We can feed a whole lot more people that way.”

Until recently, aquaculture ventures in Florida produced mostly ornamental fish for the tropical fish market, but Chapman says this is changing. “As seafood becomes scarce, we see interest shifting toward food fish,” he said.

In fact, Chapman says aquaculture production has increased over a hundredfold in the last 10 years, making it the fastest growing sector of U.S. agriculture.

He points out there’s plenty of room for U.S. consumers to incorporate farm-raised fish into their diets. “Right now we primarily consume seafood from the wild. A low percentage of our food fish comes from aquaculture. In countries like China, where aquaculture is a way of life, it’s the main source for seafood,” he said.

Despite China’s long history of fish farming, U.S. aquaculture industries are well positioned to compete in global markets since aquaculture research and technology in this country is at the forefront worldwide, according to Chapman.

One fish Chapman sees as a viable candidate for aquaculture is sturgeon. The species remains threatened after being heavily exploited in the early and mid-1900s, primarily for its caviar but also for its boneless meat, which is commonly smoked. Chapman noted that current numbers show only 3,000 sturgeon left in Florida, with most of the population in the Suwannee River, a few in the Apalachicola area and only two in Tampa Bay.

“Sturgeon has all the right characteristics,” says Chapman. “From a consumer’s perspective, it provides two delicious products — meat and caviar; it’s one of the fastest growing fish in captivity, which is good for producers; and to raise and stock sturgeon is the only way we have right now to preserve them in the wild.”

With caviar currently priced around $300 per pound, both caviar and smoked sturgeon are expensive delicacies in most countries. The eggs account for approximately 15 percent of the body weight of a female sturgeon, and a mature female fish native to Florida weighs an average of 80 to 100 pounds but can reach upwards of 400 to 500 pounds. Larger species found in Russia and other areas of the world can grow to 12 feet long and weigh as much as 4,000 pounds, Chapman said.