The Great Barrier Reef is the world\’s largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over 2,600 kilometres (1,600 mi). It is located in the Coral Sea, off the coast of Queensland in north-east Australia. The world’s largest coral reef is the only living entity that is detectable from outer space. New research shows it is also in steep decline, with half of the reef vanishing in the past 27 years, caused by various factors, including cyclones, coral bleaching and the Crown of Thorns starfish.
credit: Paul from www.Castaways.com.au