Early history The Ashmore and Cartier Islands have been visited by Indonesian fishermen since the early 1700s. Ashmore Reef was discovered by Europeans in 1811 after Captain Samuel Ashmore sighted the islands aboard the ship
Hibernia, while Cartier Reef and the neighbouring Hibernia Reef were discovered by Captain Nash in 1799 or 1800 aboard the ship
Cartier. The islands were visited by
HMS Barracouta in 1876, and two years later the government of the British
colony of Western Australia chartered a ship and authorised its captain to lay claim to the islands. The annexation was initially repudiated by the
Colonial Office as an overreach of the colonial government's authority, but in 1878 Britain took possession of the territory. At around the same time the islands were claimed on behalf of the Netherlands and the United States, but neither pressed their claims. In October 1878, the American whaling captain Amasa T. Webber claimed Ashmore Island for the United States under the
Guano Islands Act and purported to rename it the Caller Group after his vessel, the
Sadie F. Caller. The
U.S. Department of State rejected his claim two months later. Webber subsequently formed the Melbourne Guano Company with a group of Australian investors and obtained a licence to exploit its guano reserves. In 1906 reasserted possession of Ashmore Reef on behalf of the United Kingdom. The ship's commander, Captain
Ernest Gaunt, went ashore accompanied by five officers and around 200 seamen, erecting the
Union Jack on a flagpole and singing "
God Save the King", while
Cambrian returned a
21-gun salute. Britain extended its claim to include Cartier Island in 1909. There were regular reports of illegal fishing in the islands in the early 20th century, which occurred alongside poaching on islands within the state boundaries of Western Australia. Beginning in 1919, the Western Australian state government made several appeals to the Australian federal government to target vessels from
Koepang in the
Dutch East Indies. In 1923 the Australian businessman Henry Hilliard petitioned the
Department of External Affairs to grant him a fishing concession over Ashmore Reef and "complained of
perahu from Java and Timor denuding the reef of its
trepang,
trochus and seabird populations". The Australian government's response to these issues was constrained by its lack of sovereignty over the islands.
Australian administration In 1924 the Premier of Western Australia
Philip Collier requested that the territory be brought under his state's jurisdiction to combat illegal fishing.
James Henry Thomas, the British government's
Secretary of State for the Colonies, proposed in the same year that Australia begin managing the issuance of fishing licenses for the Ashmore and Cartier Islands. Australian Prime Minister
Stanley Bruce informed the Western Australian state government in February 1925 that Britain was prepared to transfer the territory to Australia, and the Western Australian premier responded that his state would be willing to administer the islands. A British
order-in-council dated 23 July 1931 stated that Ashmore and Cartier Islands would be placed under the authority of the Commonwealth of Australia once Australia passed legislation to accept them. The Commonwealth's resulting
Ashmore and Cartier Islands Acceptance Act 1933 was passed on 15 December 1933, and on 10 May 1934 the islands formally became part of Australia. The act authorised the
Governor of Western Australia to make ordinances for the territory. Due to a set of legal complications surrounding the administration of the islands by Western Australia, the state abandoned its attempts to take control of the islands in 1937, and the federal government designated the islands as part of the
Northern Territory from 19 July 1938. During the
Second World War the islands were visited by naval ships, and in the following years the territory was used for weapons testing. Navigational lights and weather monitoring stations were installed on the islands during the 1950s and 1960s. The islands also continued to be regularly visited by Indonesian fishermen; a 1949 surveying visit reported that there were 23
prahu anchored at Ashmore Reef. A
memorandum of understanding was signed with Indonesia in 1974 to allow traditional Indonesian fishermen access to parts of the territory. In 1978, when the Northern Territory was
granted self-government, administration of the Ashmore and Cartier Islands was retained by the federal government. The Ashmore Reef National Nature Reserve was established in 1983, and was followed by the Cartier Island Marine Reserve in 2000. Cartier Island was used by the Australian Defence Force as a weapons range for training exercises until sometime before 1980, and an operation was conducted in 1986 to remove
unexploded ordnance that had been left on the island. ==Geography and climate==