HMCS Caribou was an armed yacht that served in the Royal Canadian Navy during the Second World War.

Caribou had a maximum speed of 11 knots (20 km/h; 13 mph) and was armed with one QF 12-pounder 12 cwt naval gun and depth charges.

[2][3] Constructed by Defoe Shipbuilding Co. at Bay City, Michigan with the yard number 126, the yacht was launched in 1928 as Memory III on behalf of A.E.

[1][2] The vessel was sold to Sherburn M. Becker in 1930, retaining the name Memory III and remained registered in New York City.

[1] After failing to acquire any British vessels at the outset of the Second World War for auxiliary purposes, the Royal Canadian Navy discreetly searched the American market for suitable ships.

[4] Elfreda was one such ship and was acquired and renamed Marita II before being handed over to the Royal Canadian Navy in 1940.

She and fellow armed yacht HMCS Husky were the only warships patrolling the Bay of Fundy and the approaches to Saint John until the arrival of motor launches in October.