Great Barrier Reef Marine Park

conservation area, Australia

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Last updated

July 16, 2026

Quick Summary

The Great Barrier Reef is the world's largest reef complex, stretching over 1,250 miles off Australia's northeastern coast in the Pacific Ocean. It is composed of approximately 2,100 individual reefs and 800 fringing reefs, formed over millions of years by the skeletons of marine organisms like coral polyps and coralline algae. This vibrant ecosystem supports over 1,500 species of fish, six of the seven sea turtle species, and numerous other marine and bird species.1

The Great Barrier Reef Marine Park, established in 1975, manages the majority of this area and was designated a UNESCO World Heritage site in 1981. Despite its natural beauty and importance as a tourist attraction, the reef faces significant threats, including coral bleaching events linked to climate change, invasive species like the crown-of-thorns starfish, and tropical cyclones. These factors have led to substantial coral loss in recent decades.1

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Great Barrier Reef
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…largely the responsibility of the Great Barrier Reef Marine Park (declared in 1975), which encompasses the vast majority of the area. There are also smaller state and national parks. In 1981 the Great Barrier Reef was added to UNESCO’s World Heritage List.
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…largely the responsibility of the Great Barrier Reef Marine Park (declared in 1975), which encompasses the vast majority of the area. There are also smaller state and national parks. In 1981 the Great Barrier Reef was added to UNESCO’s World Heritage List.
Read More