Aerial Reef Scene	Coral Reef
Fish and Coral	Temperate Reef

Coral reefs can only thrive in the tropics where warmer water temperatures promote the chemical processes that allow calcium to be deposited from seawater. Coral reef ecosystems cannot exist in water where the winter water temperature drops much below 18 degrees celcius. Although individual corals can live in southern Australia, where temperatures drop below 12 celcius, they do not form reefs in these cold waters. The digestive processes of many groups of coral reef fishes are also temperature-dependant and these fishes cannot survive in cooler waters. (Extract from: 'The Great Barrier Reef - A World Heritage National Park'. Click HERE to purchase this book now.)