In 1983 Ashmore Reef National Nature Reserve (583 sq km) was established under National Parks and Wildlife Conservation Act 1975. Cartier Island Marine Reserve was established in 2000.
Access to East and Middle Islands the main sea bird breeding areas is by permit only. Under a Memorandum of Understanding signed by Australia and Indonesia in 1974 Indonesian traditional fishermen are allowed access to the lagoon and the fresh water supply of West Island.
Illegal killing of protected wildlife by traditional Indonesian fishermen and fishing by non-traditional Indonesian vessels are ongoing problems in the Territory and the surrounding waters.
The Royal Australian Navy and Coastwatch conduct sea and aerial surveillance of the area sometimes accompanied by officers from Department of Environment, Water, Heritage and the Arts during the fishing period (March to November). When illegal activity is suspected crews are arrested prosecuted and vessels impounded.
Following an increase in illegal fishing activity the Department of Foreign Affairs and Trade and the Australian Fisheries Management Authority conducted information and education visits to Indonesia to discourage non-traditional visits.
Ashmore & Cartier Islands Tourism