An expanded Tidewater Research Station provides more aquaculture 

 space for researcher Harry Daniels, pictured with Joanne Harcke. 



Elounder 

 FortheTuture 



By Katie Mosher 



"They may be flatfish, but the market for 

 flaky flounder filets is anything but flat. 



Rounder is popular, both among health- 

 conscious consumers in the United States and 

 in the fresh markets in Asia. But the commer- 

 cial flounder fishery has been limited in areas 

 considered overfished — and some North 

 Carolina waters have been closed to flounder 

 gill-net fisheries because of sea turtle 

 strandings. 



"As demand increases and more 

 restrictions are placed on wild populations, 

 there is a clear opportunity for aquaculture to 

 meet that demand," says Sea Grant researcher 

 Wade Watanabe of the University of North 

 Carolina at Wilmington. "Flounder is a 

 versatile fish, suited to a variety of cooking 

 styles." 



Aquaculture may be especially lucrative 

 to supply the live fish market, where flounder 

 command a premium price. 



Asian flounder aquaculture has been 



successful. In 

 1994, Japan 

 produced about 

 7,000 tons. Korean 

 production is now 

 easily three times 

 that amount, says 

 Harry Daniels, a 

 Sea Grant 

 researcher at North 

 Carolina State 

 University. 



North 

 Carolina is 

 considered a 

 breaking point in 

 the habitat for 

 summer and 

 southern varieties 

 — and Sea Grant 

 research includes 

 both. Researchers 

 anticipate commercial production operations 

 in the state within three to five years. 



"We have the fingerling production 

 problem solved," Daniels says. "We are 

 consistently and reliably producing finger- 

 lings." 



Watanabe anticipates that commercial 

 operations will utilize both natural and 

 hormone-induced spawning. "Both ap- 

 proaches are going to be needed to produce 

 the numbers necessary for commercial 

 operation," he says. 



Both Watanabe and Daniels are now 

 focusing efforts on "grow-out," taking the 

 young, finger-size fish to a market weight. 



An on-farm demonstration project for 

 summer flounder likely will be expanded for a 

 side-by-side demonstration with southern 

 flounder. Watanabe also has a demonstration 

 project in Wrightsville Beach. 



While the state's successful hybrid 

 striped bass industry uses ponds for the grow- 

 out process, flounder production will more 

 likely be done in covered tanks with 18 to 24 

 inches of water. 



Tom Losordo, an aquaculture specialist 

 with the N.C. Cooperative Extension Service, 

 has worked with Sea Grant researchers on the 

 demonstration tanks, while Christopher 



Dumas of UNC-W is reviewing the econom- 

 ics of flounder aquaculture. 



Tank systems encourage flounder's 

 natural instinct to stack on top of one another. 

 "They lay on each other like cats," Daniels 

 says. But in tanks, the feeding instinct changes. 



"In the wild they are lone predators," 

 Daniels says. "In the tanks they can be trained 

 to come up to the surface to eat dry pellets. 

 They almost school." 



Daniels' work has been boosted by an 

 expansion at NC State's Tidewater Research 

 Station in Plymouth. The aquaculture facility 

 has grown to 3,000 square feet. The state 

 legislature funded the initial facility, and 

 Southern States Cooperative funded an 

 expansion for commercial scale fingerling 

 production. 



Like some reptiles whose gender can be 

 determined by the temperature of the eggs, the 

 gender of individual flounder is determined by 

 temperature early in life. Males like the 

 extreme hot and cold temperatures — and a 

 graduate student is doing a thesis project to 

 determine the timing of the determination and 

 the turning point temperature. 



More important to the fish farmers will 

 be that females — which grow to a larger size 

 — like moderate temperatures. 



"We will need good temperature control 

 for year-round production," Daniels says. 

 "The effort will be to produce all female 

 fingerlings." □ 



N.C. Aquaculture 

 Development! Conference 



Aquaculture research, technology and 

 marketing will be highlighted during the 

 annual North Carolina Aquaculture Develop- 

 ment Conference to be held Feb. 1-3. A self- 

 guided tour of aquaculture operations will be 

 offered Feb. LA conference at the Sheraton 

 Grand Hotel in New Bern will be held Feb. 2, 

 while workshops will fill the morning of Feb. 

 3. For more information, call 9191733-7125. 

 On the Web, go to www.ncaquaculture.org. 



For information on Fishery Resource 

 Grant projects in aquaculture go to 

 www.ncsu.edu/seagrant and follow the 

 research links to the FRG pages. 



20 WINTER 2001 



