After trials and operational commissioning at Tobermory, in May 1943, the Chanticleer was assigned to the 7th Escort Group based at Greenock for convoy escort missions in the Atlantic.
In June 1943, she took part in various missions to protect convoys such as a floating dock towed from Oban to Malta by the passage through Gibraltar or the KMF18 convoy escort between Gibraltar and the United Kingdom.
In July 1943, the Chanticleer accompanied the KMF19 convoy during the passage through Beach Head, in Sicily, then joined the Eastern Support Force to support the Allied landings, Operation Husky. Upon liberation from Operation Husky, the Chanticleer resumed the escort of the Atlantic convoys and her support functions.
On 15 November 1943, at 3:24 p.m., during the defence of the combined convoy MKS30 and SL139 against the attacks from U-Boats of the Wolfpack Schill 1 (activated from 16 to 22 November 1943 and composed of the following eight U-Boats: U-211, U-228, U-262, U-333, U-358, U-426, U-516 and U-600), HMS Chanticleer was hit by an acoustic torpedo (T5-GNAT) fired from U-515, 400 kilometres east-northeast of the island of San Miguel, Azores. 29 men died.[2] The severely-damaged sloop was towed by HMS Salveda to Horta in the Azores, where it was declared a total loss.[2]
The ship was then transformed into a hulk and used as a base ship for Royal Navy personnel serving in Horta and was renamed Hesperides.[1] On 31 December 1943, her name was changed to Lusitania II,[3] but the ship continued to be used as a base ship for the remainder of the European War when it was deactivated again. She was sold for dismantling in Lisbon in 1946.[1]
Hague, Arnold (1993). Sloops: A History of the 71 Sloops Built in Britain and Australia for the British, Australian and Indian Navies 1926–1946. Kendal, England: World Ship Society. ISBN0-905617-67-3.