According to the Sea Shepherd Conservation Society, the Willassen Senior is the fifth Norwegian whaling vessel to come under attack for illegal whaling activities since 1992. The list to date includes:
The Nybraena - scuttled dockside in December 1992 (Reine, Lofoten Islands).
The Senet - Scuttled dockside in January 1994 (Fredricksberg, Norway).
The Elin-Toril - Severely damaged in 1997.
The Morild - Sunk in 1998.
The Williassen Senior - Sunk in August 2007 (Svolvaer, Lofoten Islands).