The Great Barrier Reef in Australia

The Great Barrier Reef is the world's largest reef system composed of over 2,900 individual reefs and 900 islands stretching for over 2,600 kilometres over an area of approximately 344,400 square kilometres.The reef is located in the Coral Sea, off the coast of Queensland in north-east Australia.One of the natural wonders of the world, the Great Barrier Reef off the east coast of Australia is the world’s largest coral reef. It has the distinction of being placed in the World Heritage as well as the National Heritage lists.With more than 600 islands and coral cays, the reef covers more than 300,000 sq. km. Corals make up the reefs and cays and are responsible for a huge variety of sea life in the reef — green turtles, several varieties of whales and dolphins, the dugong, about 4000 types of mollusks, 1500 different species of fish, as well as beautifully colored bird life encompassing at least 200 species. The Great Reef Marine Park is a huge tourist attraction with millions of tourists visiting the area each year. Sporting activities include reef sailing, scuba diving, and snorkeling, amongst others.

The Great Barrier Reef can be seen from outer space and is the world's biggest single structure made by living organisms. This reef structure is composed of and built by billions of tiny organisms, known as coral polyps. This reef supports a wide diversity of life, and was selected as a World Heritage Site in 1981. CNN labeled it one of the seven natural wonders of the world.The Queensland National Trust named it a state icon of Queensland. A large part of the reef is protected by the Great Barrier Reef Marine Park, which helps to limit the impact of human use, such as fishing and tourism. Other environmental pressures on the reef and its ecosystem include runoff, climate change accompanied by mass coral bleaching, and cyclic population outbreaks of the crown-of-thorns starfish.