40 Interesting Facts About the Great Barrier Reef
Below, you’ll find 40 interesting facts about the Great Barrier Reef, from its formation and history to its present condition and future preservation status.
Australia’s Great Barrier Reef is one of the great wonders of the natural world. It is the world’s largest reef system located in the Pacific Ocean.
1. The Great Barrier Reef is the world’s largest structure made of living organisms.
2. The Great Barrier Reef stretches 2300 km (1,400 mi) off the coast of Queensland state in northeastern Australia. Its width ranges from 60 to 250 km (37 to 155 mi).
3. At 344,400 km2 (133,000 mi2), the Great Barrier Reef is the world’s largest coral reef system.
4. It is around twice as large as the world’s second-largest reef, the Mesoamerican Barrier Reef System, off the coast of Mexico, Belize, Guatemala, and Honduras. It is 27 times larger than Ningaloo Reef on the country’s opposite (western) side.
5. The Great Barrier Reef is larger than Vietnam or the US state of New Mexico.
6. The Great Barrier Reef is visible from space and from the moon. It is the only living thing visible to the naked eye from space.
7. The Great Barrier Reef lies at a distance of 16 to 160 km (10 to 100 mi) off the coast.
8. More than 2900 individual reefs and 900+ islands make up the Great Barrier Reef.
9. The reef’s coral is at an average depth of 35 m (115 ft) below the surface. Some of it reaches the surface, while others are deeper than the Empire State Building.
10. The reef is composed of billions of tiny organisms called coral polyps. Each coral polyp ranges in size from 1 to 125 mm. Most are less than 10 mm.
11. There are about 40 different types of reef-building coral on the Great Barrier Reef.
12. These corals grow at an average rate of just over 1 cm (0.4 in) per year.
13. Coral has been growing on the Great Barrier Reef for 500-600,000 years. The current coral dates back about 20,000 years.
14. The Great Barrier Reef accounts for about 10% of the world’s coral.
15. The Great Barrier Reef has no atolls (ring-shaped coral reefs around a lagoon). There are about 440 atolls in other reefs around the world.
16. The Great Barrier Reef has more than 30 reef bioregions, with different types of reef structures and wildlife in each one.
17. The water temperature on the Great Barrier Reef ranges from 23°C to 29°C (73°F to 84°F), with visibility ranging from 10 to 40 meters (33–131 ft).
18. Aboriginal Australians and Torres Strait Islanders have known about and recognized the importance of the Great Barrier Reef for thousands of years.
19. French explorer Louis de Bougainville found the reef in 1768, while Captain James Cook crashed his ship on it in 1770.
20. The Englishman Matthew Flinders, the first to circumnavigate Australia by ship, named the Great Barrier Reef.
21. There are at least 800 ship and plane wrecks in the Great Barrier Reef area.
22. Most of the Great Barrier Reef is a protected area called the Great Barrier Reef Marine Park, which was established in 1975.
23. Queensland has over 200 national parks, many of which include parts of or are adjacent to the Great Barrier Reef.
24. UNESCO designated the Great Barrier Reef as a World Heritage Site in 1981. In the same year, it was added to the Australian National Heritage List, along with the likes of Uluru and Sydney Harbour Bridge.
25. CNN has called the Great Barrier Reef one of the World’s Seven Natural Wonders.
26. The Great Barrier Reef is home to over 1500 species of fish, 125 species of shark, ray, skate, and chimera, 30 species of cetacean (marine mammals), 330 species of ascidians (sea squirts), and 500 species of algae or seaweed.
27. Six of the world’s seven species of sea turtle, all of which are endangered, live on the Great Barrier Reef.
28. The nautilus lives in the Great Barrier Reef. This marine mollusk species has lived unchanged for hundreds of millions of years, leading some to call it a “living fossil.”
29. Crocodiles, seven species of frog, 118 species of butterfly, and 200+ species of bird also live near the reef.
30. Humpback whales migrate from Antarctica to the Great Barrier Reef to breed from May to October.
31. Fishing is allowed in 67% of the Great Barrier Reef Marine Park but is strictly regulated.
32. Tourism to the Great Barrier Reef generates over AUD5 billion per year, with over 2 million visitors annually.
33. There are dozens of scuba diving and snorkeling operators accessing the Great Barrier Reef, with the highest concentration in the city of Cairns and around the popular Whitsunday Islands.
34. Many operators send divers to stay aboard platforms or ships parked permanently on the reef, leading to increased diseases on those reefs.
35. More than 50% of the Great Barrier Reef’s coral has been bleached or died since 1995. Causes include farm runoff, climate change and ocean warming, dumping, and outbreaks of the crown-of-thorns starfish, which eat the coral.
36. The Great Barrier Reef is slowly moving southward and could reach as far as Tasmania within 300 years.
37. Google Maps has several underwater “street views” of the Great Barrier Reef.
38. Australian scientists discovered a new 1.5 km (0.9 mi) wide, 500 m (1640 ft) tall reef in the Northern Great Barrier Reef in 2020. It was the first new one to be discovered in 120 years.
39. In 2020, the third mass bleaching event in five years occurred in the Great Barrier Reef.
40. The Australian government has a Reef 2050 Plan, but experts and UNESCO have doubts that the plan will adequately protect the Great Barrier Reef from destruction.