The Tōhoku earthquake occurred on March 11, 2011, and was the most powerful reliably measured earthquake in Japanese history. The resulting tsunami swept the "Sai-shou-maru" out to sea and inundated its storage compartments with seawater containing marine life, including several beakfish larvae. During the ensuing two year drift across the Pacific Ocean, the fish matured into juveniles. Scientists speculate that the fish were deposited into the ghost ship by sea waves either off the coast of Japan or Hawaii.