These uninhabited islands came under Australian authority in 1931; formal administration began two years later. Ashmore Reef supports a rich and diverse avian and marine habitat; in 1983, it became a National Nature Reserve. Cartier Island, a former bombing range, is now a marine reserve.
Indonesian groups challenge Australia's claim to these islands; Australia closed parts of the Ashmore and Cartier Reserve to Indonesian traditional fishing and placed restrictions on certain catches