A vital step towards closed life cycle farming of the commercially valuable Atlantic Blue Fin Tuna (NBT) was achieved in the Adriatic farming sites of Kali Tuna, a Croatian tuna farming company and the laboratories of the University of Split. Marine scientists at Split University have confirmed that gametogenesis was completed and a number of tuna eggs were spawned in cages off the coast of Croatia.
In the experiment over 800 pieces of brood stock were kept in a special cage since the spring of 2006. The fish spawned successfully in the cage during the early summer of 2009. Most of the eggs were released naturally into the water, whilst a number of eggs were collected and later successfully hatched in a Split-based laboratory.
During the past few years the future of the NBT has become bleak, with excessive catch of the coveted fish which claims up to $25(US) a pound on the Tsukiji fish market in Tokyo.
The key to sustainability in the farming of tuna is to domesticate the NBT by creating a ‘closed life cycle’ farming process, as previously has been done with salmon and other species. This process involves breeding the fish in captivity and growing it on underutilized, small pelagic fish. Scientists and tuna farmers in Europe, Japan and Australia have for years tried to achieve hatching in captivity, a task made especially difficult by the lack of knowledge of the mating habits of the tuna. Some success has been recorded to date, by Kinki University in Japan and Clean Seas Tuna in Australia, in each case in artificial, controlled environments.