The earliest attempts to breed them artificially were in Japan. The fish were held in coastal cage nets. But although the enclosures were large, the tuna could not swim as freely as in the open sea, and often crashed into the nets and killed themselves. So the Japanese switched to catching one- to two-year-old juvenile fish to try to rear instead.
將活生生的黑鮪魚帶回陸地的困難度太高，最早試圖進行黑鮪繁殖的日本，在海邊進行箱網養殖，空間再大，還是不如大海空闊自由，黑鮪魚常常撞網而亡，日本也改由從捕捉一、二歲的小魚著手。