Chapter ONE THE GREAT BARRIER REEF Glittering coral reefs dot the shallow tropical oceans forming a broken necklace around Earth’s equator Diving down into the reefs visitors are surrounded by thousands of rainbow-colored fish darting among a forest of coral heads and branches They see the waving tentacles of corals and anemones with shy eels and octopi peeking out among the branches They see sea slugs and crabs crawling over the Many species of coral fish and other organisms make up the ecosystem of the Great Barrier Reef off the coast of Australia 5
Coral structures that are a part of the Great Barrier Reef can be seen above the water reef surfaces The largest jewel in this necklace of teeming underwater cities is Australia’s Great Barrier Reef Roughly the size of Germany or half as big as Texas the Great Barrier Reef GBR can be easily seen from space The GBR is the world’s largest barrier reef and the world’s largest living structure It stretches along the northeastern coast of the Australian state of Queensland reaching 1,400 miles 2,300 km from north of Cape York peninsula down south almost to Brisbane The Great Barrier Reef Marine Park which contains and protects the GBR is between 40 and 155 miles 60 and 250 km wide and covers an area of nearly 133,000 square miles 344,000 sq km Its treasures include approximately 3,000 individual reefs and more than 1,000 islands 1 6
The GBR is not only a region of unsurpassed beauty it is also essential to Australia’s life and economy The Australian government protects and manages the GBR through the Great Barrier Reef Marine Park Authority The reef is zoned to allow different sustainable human activities including tourism fishing boating and commercial shipping in different areas of the park Tourism commercial fishing and recreational fishing on and around the reef add 6 9 billion in Australian dollars to the Australian economy every year 2 These industries support approximately 70,000 jobs 3 But this vibrant community is dying Many scientists think it is already doomed The Great Barrier Reef Marine Park which contains and protects the Great Barrier Reef is the size of 70 million football fields 4 BIODIVERSITY OF THE GBR From the air one can see the jagged structures of the GBR curve around the coast of Australia lighter in color than the surrounding water Occasional islands break the surface The structures are masses of hard corals plus sponges and other organisms The corals produce their own hard skeletons of calcium carbonate or limestone The reef has more than 600 species of corals Some are reef-building hard corals Others are soft corals such as sea fans Living coral polyps contain single-celled algae The algae use photosynthesis to provide themselves and the polyps with energy These symbiotic algae plus the reef’s free-living algae support the ecosystem’s food web In deeper waters where the sun can’t reach hard corals cannot build massive reef frameworks but near shore sunlight and therefore reefs extend down to an average depth of 115 feet 35 m The reefs support an ecosystem of amazing complexity 7
