A group led by Maguro Bunka Kenkyukai（Tune Culture Association）, an NPO association aiming for stable supply of Bluefin tuna, launched a project to develop their own onshore farming system for commercialization. Lacking knowledge on tuna raising, they came to seek the advice of Professor Nobuhiko Akiyama at the Department of Fisheries, School of Marine Science and Technology, who is an expert in the farming of aquatic animals. The collaboration started out as technical assistance, but soon expanded into joint research entitled “Research on Onshore Farming of Tuna Using Underground Seawater.”
Onshore Farming of Bluefin Tuna Using Underground Seawater
Tokai University School of Marine Science and Technology, in cooperation with a private company, is conducting the research and development of a system that would enable complete onshore farming of bluefin tuna. The project aims to farm this large, wide-ranging fish using the University’s proprietary farming technology which utilizes underground seawater. The bluefin tuna raised in five-meter diameter tanks has now grown to exceed 50 centimeters in length. The next step is to study the tuna’s growth, health conditions and meat quality for further farming experiments at a larger farming plant.
Bluefin tuna fry in the farming facility
Bluefin tuna grew to be 3,300ｇ after 5 months
How the industry-government-academia collaboration started
Farming technology using underground seawater – less susceptible to typhoons and water contamination, and prevents marine pollution
The farming tanks are located on the University’s School of Marine Science and Technology campus located in Shimizu District, Shizuoka Prefecture. The underground seawater there has a constant temperature all year round and contains no detectable aerobic bacteria because the water is anoxic, so we can pump clean seawater that is always at a temperature suitable for farming fish. This underground seawater is also used at the University’s aquarium located in the same district. The Department of Fisheries has also been conducting research on new species for farming, including higher added-value abalone and seahorse. From such other projects, a new mechanism was devised in which a semi-circulation system is used instead of constantly supplying fresh seawater. The purpose of this is to save water while maintaining the temperature and quality of the water. This system is now being used for the bluefin tuna farming facility.
This farming technology, which utilizes underground seawater, is a versatile system that can also be used for fish species other than tuna, such as great amberjack and flatfish. Compared to offshore fish farms, onshore tanks reduce the risk of loss due to typhoons and water contamination, prevent marine pollution from leftover feed and fish droppings, and allow feed intake traceability to ensure safety and security of food. This joint research aims to utilize the new technology of using underground seawater to commercialize this onshore tank farming system, but the ultimate goal is to establish a complete system onshore for farming tuna from eggs.
Patent: “Onshore Tuna Farming System”
