South Australia Kangaroo Island and Backstairs Passage / from the survey by B. Douglas Esq. Naval Officer and Harbour Master Nov. 1857 ; lithographed by Rich d Jn. Loveday

William Bloomfield Douglas (25 September 1822 – 5 March 1906), was a Welsh naval officer and public servant. During his career, he served in various positions in South Australia, including Government Resident of the Northern Territory (1870–1873), the Straits Settlements, Acting Resident of Selangor (1875–1882). In December 1854, Douglas assumed the role of naval officer and harbour master in Adelaide, South Australia. He took on additional responsibilities, including Collector of Customs, Master of Trinity House, and chairman of the Harbour Trust. These positions were later consolidated into the Marine Board, with Douglas appointed as its first president. Douglas was involved in official inquiries regarding lighthouses, harbours, and defence's in South Australia from 1855 to 1858. He conducted surveys of Kangaroo Island, the Backstairs Passage, and the mouth of the Murray River.