is an uninhabited and unvegetated sand cay in a platform reef in the Timor Sea
north of Australia
and south of Indonesia
. It is located at 12°31'S 123°33'E, on the edge of the Sahul Shelf
, about 300 kilometres off the north west coast of Western Australia
, 200 kilometres south of the Indonesian island of Roti
, and 70 kilometres south-east of Ashmore Reef
. It is within the Territory of Ashmore and Cartier Islands
, an external territory
The area within of the centre of the reef is protected as the Cartier Island Marine Reserve
. At the southern edge of the reef is a shipwreck
of the Ann Millicent
, an iron-hulled barge of 944 tons wrecked in 1888. The remains of an RAAF Beaufighter
can also be seen at low tide. Formerly used as a bombing range
, access to the island is prohibited because of the risk of unexploded ordnances
. The area is still a gazetted Defence Practice Area, but is no longer in active use.
Cartier Island is completely unvegetated except for the seagrass Thallassia hemprichii
, which grows in pockets of sand within the reef, and may be exposed at low tide.
The island was charted in 1800 and named after the ship Cartier
. Its charted position was somewhat inaccurate until corrected in 1878 during a hydrographic survey by Lieutenant William Tooker in the Airlie
. On 5 January 1888 the Ann Millicent
was wrecked on the island during a voyage from the Gulf of Carpentaria
, South Australia
. In 1909 it was annexed by the......