I agree, the Great Barrier Reef is an ecosystem on itself, supporting the world’s greatest concentration of marine life in the planet as we know. 15,000 fish species, 350 kinds of coral, molluscs made up 4,000 of the species type and 10,000 on just the species of sponges. It is also the breeding area for seabirds, dugongs, sea turtles and humpback whales. Not only that, hundreds of algaes species and seaweeds all live on the reef, becoming a vital part of the reef life. It’s a habitat and shelter for millions of marine organisms.