HMCS Tuna was a commissioned torpedo boat of the Royal Canadian Navy (RCN) that served during the First World War. Built as the high-speed civilian yacht Tarantula, the vessel was one of several converted yachts the RCN used during the war.
Built by Yarrow Shipbuilders in the United Kingdom, Tarantula was a high speed private luxury yacht designed for W.K. Vanderbilt, Jr.. Among the first turbine-powered private yachts, she was used for commuting in and around New York City.
In 1914, Jack Ross, a Canadian industrialist and millionaire, purchased the Tarantula, arranged for her conversion for military use, and donated her to the RCN. The ship was commissioned as HMCS Tuna, with Ross in command. She was designated as a torpedo boat after the installation of two torpedo Tubes. She was also fitted with guns for self-defense, and was assigned to patrol duties. Based out of Halifax, she was a common sight in Bedford Basin. In the spring of 1917, the Tuna was paid off due to an irreparable engine mount fracture. She was sold for salvage in June, 1918, and stripped. Her hull remained in Halifax's Northwest Arm until the 1930s.
Built as the high-speed civilian yacht Tarantula