CGS Margaret was a Canadian Government Ship, and was the first vessel to be built specifically for the Customs Preventive Service. Delivered in 1914, she was transferred to the Royal Canadian Navy and served as HMCS Margaret during World War I. Following the war, Margaret was returned to the Customs Preventive Service, and was transferred to the Royal Canadian Mounted Police in 1932. Sold shortly thereafter, she was subsequently acquired by the Brazilian Navy and renamed Rio Branco.