The largest reef in the world is the Great Barrier Reef located off the coast of Australia. Bigger than the entire country of Italy, this reef system measures 1,249.1 miles (2,011 km) in length and 44.7 miles (72 km) across at its widest point. The reef is not a continuous structure but is made of more than 2,800 individual reefs. More than 400 types of coral, 1,500 species of fish, 4,000 types of mollusks, and 400 kinds of sponges make their homes in the Great Barrier Reef. Other animals there include anemones, worms, crustaceans, and echinoderms.
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| Great Barrier Reef located off the coast of Australia. Source from: australia.gov.au | . |
The reef supports sea grass beds that are feeding grounds for the dugong, an endangered mammal, as well as for the endangered green and loggerhead turtles. The reef is also used by humpback whales that travel from the Antarctic to give birth in its warm waters.
The Great Barrier Reef is the bestknown marine protected area in the world. Because it is a living classroom of natural history and science, the reef was declared a marine park in 1975 to preserve its condition while providing reasonable use.