Volume 19, Number 6 • November-December 2001

The Science of Closed Systems

Yonathan Zohar with
a sea bream.

One of the country's leading research institutions in developing marine indoor recirculating systems is the University of Maryland's Center of Marine Biotechnology (COMB) in Baltimore's Inner Harbor. Led by Yonathan Zohar, COMB is taking a multidisciplinary approach for moving fundamental research from the lab to the farm. While Zohar's work involves analyzing the reproductive hormones and biochemical reactions that cause fish to become gravid, COMB researchers have been focusing on a suite of other issues as well, from nutritional needs of different life stages to new microbial communities that can make marine circulation systems more economically feasible. A major concern in aquaculture of carnivorous species is the use of fish meal in fish feed. As Zohar says, "we're taking fish to feed fish." That is one reason that they have begun studying new feed formulations that can reduce dependence on wild-caught fish.

More than a decade ago, Zohar came to the U.S. from Israel, which has a highly developed aquaculture industry. He and his colleagues in Baltimore have successfully spawned both striped bass and sea bream, a high value and popular European species farmed in netpens in the Mediterranean. Not only have they spawned them, but they have developed techniques to enhance their growth. While sea bream normally take about sixteen months to grow from fingerling stage to one-pound market size, in COMB's specially controlled recirculating marine systems, sea bream have been brought to harvest in a mere nine months.

Sea bream, notes Zohar, appear on the menus of numbers of seafood restaurants in this country, and he believes U.S. aquaculturists could raise sea bream in recirculating tanks and market them profitably. He admits, however, that upfront investment costs will likely prove sizeable, and that despite the high price that sea bream now commands, it may take a private aquaculturist a couple of years to realize profits. These are the kinds of considerations aquaculturists have to deal with as the industry continues to mature.

Top of Page

		Contents of this issue	Other Issues