Croaker was a Gato-class submarine, SS-246. Electric Boat at Groton laid her down on 1 April 1943, launched her on 19 December 1943, and the Navy commissioned her on 21 April 1944. John E. Lee had her from that day. The Dictionary of American Naval Fighting Ships prints the launch as 19 December 1942. That date cannot follow a keel laid in April 1943, so the date kept here is 19 December 1943.
Her first patrol left Pearl Harbor on 19 July 1944. On 7 August, west of the Amakusa Islands, she sank the light cruiser Nagara. She also sank two freighters, on 14 August and on 17 August. The Dictionary of American Naval Fighting Ships gives the boat a Navy Unit Commendation for the patrol.
She made six war patrols. Three battle stars are recorded, for the first, the second, and the fifth.
The Dictionary says she was decommissioned and placed in reserve on 15 May 1946. NavSource dates that decommissioning 15 June 1946. She was recommissioned on 7 May 1951, decommissioned on 18 March 1953 for a hunter-killer conversion, designated SSK-246 on 9 April 1953, and recommissioned on 11 December 1953. She was decommissioned again on 2 April 1968 and struck on 20 December 1971. She is a museum ship at Buffalo.