The remaining species provide us with the resources and the recreational opportunities we need. That means our biodiversity is coming under increasing pressure . Australia's marine biodiversity Australia, the world's largest island, has a perimeter of about 36 000km. The coast and marine environments range from the tropical north to temperate southern zones. The boundary of the exclusive economic zone is 200 nautical miles from the coast so our marine environment covers about 9 million square kilometres of oceans and seas.
Many habitats occur around the coastline.
Rocky shores , sandy beaches, algal reefs and kelp forests dominate the cooler, temperate south. Coral reefs, bays, estuaries, mangroves and tropical saltmarshes dominate the north. Australia has some of the most diverse, unique and spectacular marine life in the world. It has the largest area of coral reefs, the highest mangrove species diversity, the highest diversity of marine macroalgae and the highest diversity of temperate seagrass in the world. All major groups of marine organisms are present in Australian waters, and many are endemic or unique to Australia.