Bluefin tuna adapted to conditions in captivity. (Photo: IEO)
Another step forward in the domestication of bluefin tuna
Wednesday, December 01, 2010, 04:40 (GMT + 9)
A team of researchers from the Spanish Institute of Oceanography (IEO) have been able to, for the first time in Europe, adapt captive juvenile bluefin tuna (Thunnus thynnus) in ground facilities. So far, this has only been achieved with four species of tuna in Japan, Australia and the United States.
The project was carried out by scientists Fernando de la Gándara and Aurelio Ortega, and technicians Juan Ramón Prieto and Javier Viguri of the tuna farming team from the IEO. The research is taking place at the Centre for Marine Cultivation of the Oceanographic Centre of Murcia, where they managed to adapt a school of juvenil bluefin tuna, caught off the coast of Murcia, to ground facilities.
The tuna, which weigh one kilogram, have spent the last 15 days in a fiberglass tank where they are being fed chopped anchovy and sardine, and appear to be showing "very active feeding behavior," said the IEO.
This adaptation has been tried unsuccessfully in previous years. This time it was achieved through the use of a tank of larger proportions, and improved methods of capture, transport and handling.
This positive result represents a breakthrough in the domestication of the species, which had been successfully achieved in Japan, Australia and America, with Pacific bluefin tuna (Thunnus orientalis), southern bluefin tuna (Thunnus maccoyii), yellowfin tuna (Thunnus albacares) and blackfin tuna (Thunnus atlanticus), but not for the Atlantic bluefin tuna (Thunnus thynnus).
Some of the bluefin tuna were caught by trolling with a hook without killing them off the coast of Mazarrón, and transported directly to the facilities of the Centre for Marine Cultivation in Mazarrón.
Others were caught off Cape Palos which were previously accustomed to captivity in cages located in the bay of El Gorguel before being transported to IEO facilities in Mazarrón.
In the first case they achieved a 70 per cent survival rate, while the second was 100 per cent, mainly because these fish were already adapted to captivity in cages.
This activity is part of the third phase of the European project SELFDOTT (Self-sustained Aquaculture and Domestication of Bluefin Tuna), which studies the progress of cultivation of bluefin tuna in captivity.
The research aims to develop artificial diets for this species that are efficient and environmentally friendly.
The techniques implemented for the adaptation of bluefin tuna in captivity in ground facilities will be used in the TANQUE project, cofinanced by FEDER.
This project, led by Aurelio Ortega, will provide the IEO with a great facility for the reproduction of bluefin tuna, which consists of a tank which is 25 meters in diameter and 12 meters deep. There they plan to hold the bluefin tuna broodstock to obtain viable eggs from this species.
- IEO begin fattening bluefin tuna born in captivity
- Mass bluefin egg layings obtained without hormonal induction
- Bluefin tuna breeding breakthrough may spur sustainability
By Silvina Corniola