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Raising red drum in Europe

The red drum is an important fish for United States aquaculture and stock enhancement.

Scientists in Italy have conducted research on the reproductive parameters and larval rearing of red drum  (Sciaenops ocellatus), maintained in captivity for the first time in Europe.

The species is not indigenous to Europe — in the 1980s, it was introduced in captivity in Central America and the Caribbean, Ecuador, Taiwan and Hong Kong.

For this research, juveniles of red drum were taken from the United States in the late 1990s and in early 2013, 40 of them were held in a closed recirculating system at Lestina farm in Southern Italy. The fish ranged from 34 to 47 centimeters in length. The system had a water flow of 6,000 liters per hour, the water temperature ranged from 21 degrees Celsius to 28.8 degrees Celsius and the water salinity ranged from 25 to 27 grams per liter.

During the study, the fish were fed commercial feed pellet containing 46 percent protein at 1.1 percent of body weight every day. By the end of July, about six months into the experiment, approximately 43 spawns were recorded and a mean number of 66.5 million eggs were collected during the spawn period. The fertilization rate was 30 to 80 percent.

Cannibalism was observed as larger larvae preyed on smaller ones, so to limit the phenomenon red drum population was selected for size at 35 days after hatching.

“The red drum is an important fish for United States aquaculture and stock enhancement,” the authors wrote. “Although this carnivorous and euryhaline sciaenid is endemic to the Gulf and Atlantic coasts of the US, its aquaculture production is expanding in several countries.”

The authors, which included University of Bari Aldo Moro’s Mariateresa Lastilla, Gerardo Centoducati and Michele Deflorio and Lesina’s Fulvio Cepollaro and Andrea Novelli, deduced that red drum has certain “desirable characteristics,” well-suited to aquaculture, such as rapid growth, a wide salinity tolerance and a large commercialization size useful for processors.

The researchers concluded that t is possible to spawn red drum in Europe, “it is time to start to study growth performance parameters of Sciaenops ocellatus from juveniles to commercial size.”

“Nonetheless, as aquaculture technologies become more advanced it is likely that red drum production will continue to rise worldwide through increased efficiency of existing farms and expansion to additional countries,” they said. “Further research on feed efficiency, disease treatment, temperature tolerance and rearing in recirculating aquaculture systems will help to ensure the ecologically and economically sound production of this species in coming years.”