Career
Built:	1803
Launched:	6 August 1803
Commissioned:	September 1803
Fate:	Captured at sea, 12 July 1814
General characteristics
Displacement:	240 tons
Length:	94 ft 3 1/2 in (28.7 m)
Beam:	27 ft 9 in (8.5 m)
Draught:	12 ft 6 in (3.8 m)
Propulsion:	Sail
Speed:
Complement:	120 officers and enlisted
Armament:	16 x 24 pounder (11 kg) carronades

The USS Syren (later Siren) was a brig in the United States Navy during the First Barbary War and the War of 1812.

Syren was built for the Navy in 1803 at Philadelphia by Nathaniel Hutton and launched on 6 August 1803. She was commissioned some time later in the month of September, Lieutenant Charles Stewart in command.

The brig departed Philadelphia on 27 August 1803 and reached Gibraltar on 1 October. A fortnight later, she sailed via Livorno to Algiers carrying presents and money to the Dey of Algiers. She then sailed to Syracuse where she arrived early in January 1804.

Meanwhile, the previous autumn, American frigate Philadelphia had run aground off Tripoli and had been captured by Tripolitan gunboats. To prevent the frigate from opposing his planned operations against Tripoli, the commander of the American squadron in the Mediterranean, Commodore Edward Preble, decided to destroy her. To achieve this end, Syren and ketch Intrepid got underway from Syracuse on 3 February 1804 and proceeded to Tripoli which they reached on the 7th. However, before the American ships could launch their attack, they were driven off by a violent gale and did not get back off Tripoli until the 16th, when sailors from the Intrepid succeeded in burning the Philadelphia.

Syren returned to Syracuse on the morning of 19 February. On 9 March, she and Nautilus sailed for Tripoli. Soon after their arrival, Syren captured a polacca called Madona Catapolcana and sent her to Malta. Toward the end of the month, she cast off and captured the armed brig Transfer belonging to the Pasha. Stewart named her Scourge, and she served the American squadron under that name.

Syren cruised in the Mediterranean during the spring and summer of 1804 and participated in the attacks on Tripoli in August and September 1804.

Syren continued to support the squadron's operation against Tripoli which forced the Pasha to accede to American demands. After a treaty of peace with Tripoli was signed on 10 June 1805, the brig remained in the Mediterranean for almost a year helping to establish and maintain satisfactory relations with other Barbary states.

Syren departed Gibraltar on 28 May 1806 and reached the Washington Navy Yard on or about 1 August. She was laid up in ordinary there until reactivated in 1807, and carried dispatches to France in 1809. The following year, her name was changed to Siren.

Little record has been found of the brig's service during the War of 1812, but we do know that she was captured at sea by the 74-gun ship of the line HMS Medway on 12 July 1814 after an 11-hour chase during which Siren jettisoned her guns, anchors, cables, boats, and spare spars in a valiant but futile effort to escape from the British vessel. Among the prisoners was Samuel Leech, who later wrote an account of his experiences.

As of 2005, no other ship has been named Syren.