Swan (AM-34), a minesweeper, was laid down at Mobile, Ala., on 10 December 1917 by the Alabama Dry Dock & Shipbuilding Co.; launched on Independence Day 1918, sponsored by Miss Hazel Donaldson; and commissioned at New Orleans, La., on 31 January 1919, Lt. (jg.) Fredman J. Walcott, USNRF, in command.

Swan completed final acceptance trials on 8 June 1920 and was assigned to Division 2 of Mine Squadron 2 of the Atlantic Fleet. She operated out of Portsmouth, N.H., until 23 May 1922, when she was decommissioned there. The minesweeper was placed in commission again on 23 June 1923. That fall, she was assigned to the Washington Navy Yard but operated out of Quantico, Va. By the spring of 1926, Swan changed duty stations again, working for the 15th Naval District out of Coco Solo in the Canal Zone. On 30 April 1931, while still in the Canal Zone, she was designated a "minesweeper for duty with aircraft," presaging her later change of designation. She decommissioned again on 21 December 1933, this time at San Diego, Calif. A little over three months later, on 2 April 1934, the minesweeper was recommissioned and reassigned to the Fleet Air Base at Pearl Harbor. On 22 January 1936, Swan was officially redesignated a small seaplane tender, AVP-7.

For the next five years, Swan operated as a tender for Patrol Wing (PatWing) 2 out of Pearl Harbor. On the morning of 7 December 1941 she was resting on the Marine Railway dock at Pearl Harbor when Japanese planes swooped in on the ships in the harbor. Her crew saw the first bomb dropped on the south ramp of the Fleet Air Base at 0755. Eight minutes later, she opened fire with her 3 inch antiaircraft battery. The next few hours were so hectic for her that her crew could not maintain a chronological log of the action, but they did claim an enemy plane for their 3-inch battery. Though she had been in drydock for boiler upkeep, her engineers had her ready to refloat by 1315.

Swan remained in Pearl Harbor for another month, assisting in the salvage work. Then, on 8 January 1942, she got underway for American Samoa. She arrived at Pago Pago on the 18th and remained until 25 July, except for a voyage to Danger Island in midMarch and a month-long visit to Wallis Island from late May to early July. She headed back to Pearl Harbor on the 25th and arrived on 4 August. She was overhauled there and, after loading ammunition and supplies at Kaneohe Naval Air Station, from 28 to 30 October, got underway to return to the South Pacific. On this voyage, she visited Canton Island, Suva in the Fiji Islands, Funafuti in the Ellice Islands, Gardner Island, Sydney Island, Hull Island, and Palmyra Island. She departed Palmyra Island on 8 December and returned to Pearl Harbor on the 13th. Swan put to sea again on the 30th to carry supplies to Canton Island. She unloaded her cargo there on 7 January 1943 and reentered Pearl Harbor on the 16th. The tender remained at Pearl Harbor until 12 March when she sailed to Johnston Island to tow YC-811 back to Pearl Harbor.

Swan returned to Pearl Harbor on 23 March and from then until the beginning of May, she assisted the fleet air wing by towing targets for bombing practice. From 8 to 22 May, she made a voyage to Tern Island of French Frigate Shoals, located about halfway between the main Hawaiian Islands and Midway Island. Upon her return to Pearl Harbor, she resumed target towing duties, this time for torpedo bombers. Between 1 and 7 June, she made another round-trip voyage to French Frigate Shoals and back, then resumed target towing and torpedo recovery duty.

For the next two years, Swan's area of operations was confined to the immediate vicinity of the major islands of the Territory of Hawaii. She continued to participate in training missions by towing targets and recovering torpedoes for both planes and ships. She also transported passengers and cargo between the islands and rendered other auxiliary services.

By June 1945, she was in the Consolidated Shipyard in Los Angeles, Calif., undergoing a major overhaul. She remained there through the month of July and into August. On 13 August, Swan headed back to Pearl Harbor and arrived on the 21st. She resumed her routine until 6 October, when she set sail for San Diego. After a two-day stop there, on the 15th and 16th, she continued on to the Panama Canal. She arrived at Coco Solo in the Canal Zone on 28 October and, two days later, continued on to Boston, Mass. She reported to the Commandant 1st Naval District, at Boston on 9 November. On 13 December 1945, pursuant to the findings of a board of inspection and survey, Swan was decommissioned at Boston. Her name was struck from the Navy list on 8 January 1946 and, just over nine months later, on 12 October her hulk was delivered to the Maritime Commission at Newport, R.I., for disposal.

Swan earned one battle star during World War II.