Aquacultural Survey in Japan
The purpose of this survey was to assess the value of Japan's aquacultural methods in terms of direct or indirect application in other countries, and to evaluate present and future status of aquacultures in Japan. The aquacultures discussed are: Ayu, Japanese eel, Yellowtail, Japanese oyster, and the Japanese Kuruma shrimp. Japan is faced with serious problems in most of its aquacultures. Only a few of the methods of culture developed can be applied in other countries. If present methods are continued, many cultures will suffer limited growth and some may decline. The most serious problem and the ultimate limiting factor is the cost of production. Feed and labor are the two primary cost items of all cultures. Pollution is another problem. Another problem is having to depend on natural populations for young animals for stocking. A potential disease problem results from the feeding of uncooked trash fish also, and this particular problem has manifested itself in the yellowtail culture. Various stocking programs and ways to artificially reproduce fish stocks are discussed.