Posted on July, 08 2002

Rome, Italy - A Japanese research institute for fish has announced the first successful breeding of bluefin tuna in captivity. WWF believes that this achievement will do nothing to save blue fin tuna, which is on the brink of collapse due to over-fishing and tuna farming . The captive breeding experiment would take several years to perfect, and meanwhile, the species could disappear in the Mediterranean. "We are in a state of emergency. Experiments in captive breeding of blue fin tuna should not prevent governments and the EU from decreasing fishing effort on wild tuna stock, and from regulating the new and ever-growing trend of tuna farming when reforming the Common Fisheries Policy this year," declared Paolo Guglielmi, Head of the Marine Unit at the WWF Mediterranean Programme Office. Nicknamed "the Diamond of the Ocean", bluefin tuna has great market demand, is highly appreciated by sushi gourmets and therefore sought after by Japanese fishing fleets. It has been reported that Japanese researchers have now managed to breed tuna in captivity, a process that has been earlier attempted with little success by researchers in Japan, Australia, and the Mediterranean region. It remains to be seen if this lab experiment in tuna breeding can be applied on a large scale, a process that may well take several years. WWF believes that this captive breeding, when finally developed, will be ecologically unsustainable due to fishing pressure on small pelagics used for feeding tuna. Tuna is ranked among the top predators of the marine ecosystem. A key study on the contribution of aquaculture on world fish supplies (Naylor et al., 2000, Nature) reports that on average, more than 5kg of wild fish are needed to obtain 1kg of a carnivorous marine fin fish, such as bluefin tuna, from aquaculture. These numbers have significant meaning when considering that tuna is a massive fish that grows to over 3m and weighs more than 650kg. While fish farming may be a legitimate business, farming of fish that eat other fish will not solve the fish supply crisis. In addition, the large quantities of fish caught to feed tuna would not be available for other wild fish species which depend on them for food, thus affecting the food chain and modifying the whole ecosystem. Furthermore, this practice would involve the concentration of tuna wastes in one place, thus polluting surrounding areas. Finally, the economic feasibility of tuna aquaculture remains unaddressed. It is important to ascertain whether breeding tuna is a process that is technically and economically feasible at a commercial level. Reaching this stage of feasibility would take several years at best. The likelihood is that the current system of fishing-for-farming would be far more economically profitable than putting in place a true aquaculture system based on tuna hatcheries to produce tuna larvae, involving high investment. For further information: Anne Rémy Head of Communications, WWF Mediterranean Programme Tel: + 39 06 844 97 424/417 E-mail: aremy@wwfmedpo.org