After her commissioning, the Stickleback arrived at Guam on August 2, 1945. After several days of training, she sailed for the Sea of Japan. She was one of the second wave submarines to enter the "backyard sea" after the Hellcats. On August 13, she made it through the Tsushima Straits mine fields safely, but the atomic bombs had already been dropped and it was certain that the war would end soon. After two days on war patrol, no worthwhile targets were encountered and a cease fire order ended the extremely brief fighting career of the Stickleback.