A voracious green and silvery fish with elongated pike-like body and long narrow jaws.
The first Guardfish, a fleet submarine, was launched by the Electric Boat Co. of Groton, Conn., 20 January 1942, sponsored by Mrs. Edward J. Marquart. She commissioned at New London, Conn., 8 May 1942, Lt. Comdr. T. B. Klakring in command.
After conducting shakedown out of New London, Guardfish departed that base 28 June 1942 for Pearl Harbor via the Panama Canal, and arrived there 25 July to prepare for her first cruise. Her first war patrol was in the hitherto unpatrolled waters off northeast Honshu. Guardfish departed Pearl Harbor 6 August 1942, sank a trawler 22 August, and 24 August sank 3,114-ton cargo ship Seikai Maru off Kinkasan Harbor. Eva'ding escort vessels, she proceeded up the coast and found a convoy 2 September. Guardfish attacked the next day, sinking 5,253-ton Kaimei Maru and 1,118-ton cargo ship Tenyu Maru. Chita Maru, a 2,376-ton freighter, retreated into the harbor and anchored, but a remarkable long-range shot from Guardfish left her resting in the mud. Guardfish returned to Midway from her spectacularly successful first patrol for refit 15 September 1942.
Guardfish departed Midway on her second war patrol 30 September and headed for the East China Sea. Surviving a violent attack by patrolling aircraft 19 October, Guardfish closed a seven-ship convoy 21 October, sinking a 4,000-ton freighter and 6,362-ton Nichiho Maru north of Formosa as the convoy scattered. After evading pursuing aircraft and surface ships, Guardfish returned to Pearl Harbor 28 November 1942. For her outstanding success on war patrols 1 and 2 Guardfish received a Presidential Unit Citation.
Moving her base of operations to the Truk area, Guardfish departed Pearl Harbor 2 January 1943 to patrol off the Japanese stronghold. She sank a Japanese patrol craft 12 January west of Kavieng, and a 1,300-ton cargo ship the next day. Attacked by destroyer Hakaze 23 January, Guardfish sent her to the bottom with a well-placed torpedo. Moving south toward Rabaul, slip attacked a largo convoy near Simpson Harbor, but was driven off by concentrated shore fire and escort attacks. Guardfish ended her third patrol by arriving at Brisbane, Australia, 15 February 1943.
Her fourth war patrol was conducted in the Bismarcks. Solomons, and New Guinea area, and Guardfish recorded no kills during this cruise, 9 March to 30 April 1943.
Departing Brisbane for the same waters 25 May 1943, Guardfish sank 201-ton freighter Suzuya Maru and damaged another before being forced down by aircraft 13 June. She picked up a surveying party on the west coast of Bougainville 14 July and returned to Brisbane for refit 2 August 1943.
Guardfish departed Brisbane for her sixth war patrol 24 August 1943, landing a reconnoitering party on Bougainville and then moving into cruising waters. She sank 5,460-ton Kasha Maru 8 October and subsequently spent 2 days as lifeguard ship during the air strikes on Rabaul. Guardfish embarked another reconnoitering party 19 October at Tulagi, landed them on Bougainville, and took vital soundings in Empress Augusta Bay before embarking the Marine party 28 October. These important missions were carrier out a scant 2 days before the American landings at Bougainville. Guardfish reached Brisbane, closing out her sixth patrol, 3 November 1943.
Turning to the shipping lanes between Truk and Guadalcanal, Guardfish began her seventh war patrol 27 December 1943, sinking 10,024-ton oiler Kenyo Maru 14 January 1944. She then closed Truk, and sank destroyer Umikaze 1 February during an attack on a convoy. After serving briefly as lifeguard ship off Truk she arrived at Pearl Harbor 18 February and from there returned to San Francisco for repairs 9 days later.
Guardfish again put to sea from San Francisco and arrived at Pearl Harbor 1 June. She then joined submarines Thresher, Piranha, and Apogon to form the famous coordinated attack group known as the "Mickey Finns," commanded by Captain W. V. O'Regan in Guardfish. The submarines patrolled the shipping lanes around Formosa with spectacular success, Guardfish sinking 5,863-ton auxiliary Mantai Maru, 2,838-ton cargo ship Hizan Maru, and 5,215-ton cargo ship Jinsan Maru southwest of Formosa 17 July. After damaging another freighter 18 July, Guardfish sank 5,872-ton Teiryu Maru the next day, barely escaping the attacks of her escort vessels. She arrived at Midway for refit 31 July 1944, and for her outstanding performance on the eighth patrol was awarded a second Presidential Unit Citation.
Putting to sea as a member of a wolfpack 23 August 1944, Guardfish and the other submarines, Thresher and Sunfish, had a 40 minute surface gun battle with sampans 2 September. On 25 September she attacked and sank 873-ton cargo ship Miyakawa Maru #2 in the Sea of Japan, her cruising ground for this patrol. Guardfish returned to Pearl Harbor 24 October 1944.
Guardfish departed 26 November for her 10th war patrol to cruise in the "Convoy College" area of the South China Sea, with a wolfpack. She recorded no sinkings during this cruise, but nearing Guam in the early morning darkness of 24 January she mistook Extractor, an American salvage ship, for an I class submarine and torpedoed her. Guardfish succeeded in rescuing all but 6 of her crew of 79 from the sea, and terminated her patrol at Guam 26 January 1945.
Guardfish's llth war patrol was spent watching for enemy fleet units attempting to escape from the Inland Sea of Japan by way of Kii Suido. Departing Saipan on this duty 27 February, she found no ships but rescued two downed aviators 19 March before returning to Midway 11 April 1945.
Guardfish departed Midway 8 May 1945 on her 12th and last war patrol, and was assigned lifeguard station for the ever-increasing air attacks on the Japanese mainland. She sank a small trawler with gunfire 16 June, and arrived back at Pearl Harbor 26 June 1945.
The veteran submarine served with the training command after her return to Hawaii, helping to train surface ships in the newest antisubmarine warfare tactics until 25 August 1945. She then sailed for the United States, transiting the Panama Canal 12 September and arriving at New Orleans 16 September. Guardfish arrived at New London 6 November and decommissioned there 25 May 1946.
Guardfish remained inactive until 18 June 1948, when she was placed "in service" for duty as a Naval Reserve Training Ship at New London. Declared in excess of Navy needs, her name was struck from the Navy List 1 June 1960. Appropriately, this ship, one of the most successful of World War II submarines, performed her last service as a target ship for a new submarine torpedo. Dogfish and Blenny sank her with the newly developed torpedoes off New London 10 October 1961.
Guardfish earned 11 battle stars for her World War II service. Her first, second, third, fifth, sixth, seventh, eighth, ninth, and eleventh war patrols were designated successful.