[3] The Shōnan Maru 2 is similar in design and appearance to whale catchers used by the ICR such as the Yūshin Maru series, the primary external differences being the presence of a crane near the aft end of her superstructure used to launch and recover rigid-hulled inflatable boats (craft not carried aboard other ICR whale catchers), minor differences in the design of the bridge section and forward catwalk, and the absence of a structure on her prow used to recover fired harpoons.

Originally, the Shōnan Maru 2 sported the same blue & white paint scheme as the ICR whale catchers, but in late 2011 she was repainted to an overall white scheme, the word "Research" on the side of her superstructure being replaced with "Government of Japan" In late 2009, the Shōnan Maru 2 intercepted and pursued the MY Steve Irwin, being shown with a water cannon mounted on the bow in place of a harpoon.

The ship trailed the Steve Irwin from a distance before closing in and engaging the Sea Shepherd vessel with water cannons and a long-range acoustic device (LRAD).

[5] The New Zealand government expressed concern at the risk of human lives in the hostile environment, and it also repeated its opposition to whaling in the Sanctuary.

AMSA was unable to verify claims made by Sea Shepherd, while the Japanese government declined to participate with the investigation, saying any information it had might be needed for an inquiry by its own authorities.

[9] On February 15, 2010, Peter Bethune, then member of the Sea Shepherd Conservation Society and the skipper of the Ady Gil, boarded the Shōnan Maru 2 without permission.