40 Awe-Inspiring Facts about the Great Barrier Reef

Australia’s Great Barrier Reef is one of the great wonders of the natural world. Below you’ll find 40 interesting facts about the Great Barrier Reef, from its formation to present condition and future preservation status. 

  • The Great Barrier Reef is the world’s largest structure made by living organisms.  
  • The Great Barrier Reef stretches 2300 km (1,400 mi) off the coast of Queensland state in northeastern Australia. It’s width ranges from 60 to 250 km (37 to 155 mi). 
A map of Australia with the Great Barrier Reef labeled
Australia, with the Great Barrier Reef indicated at the top right
  • At 344,400 km2 (133,000 mi2), the Great Barrier Reef is the world’s largest coral reef system.  
  • The Great Barrier reef is larger than Vietnam or the US state of New Mexico.  
  • The Great Barrier Reef is visible from space and from the moon. It is the only living thing visible with the naked eye from space. 
Image of the Great Barrier Reef shot from the sky
The Great Barrier Reef from above
  • The Great Barrier Reef lies at a distance of 16 to 160 km (10 to 100 mi) off the coast.  
  • More than 2900 individual reefs and 900+ islands make up the Great Barrier Reef. 
  • 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.  
Different kinds of coral on the Great Barrier Reef
Various types of coral growing on the Great Barrier Reef
  • There are about 40 different types of reef-building coral on the Great Barrier Reef.  
  • These corals grow at an average rate of just over 1 cm (0.4 in) per year. 
  • Coral has been growing on the Great Barrier Reef for 500-600,000 years. The current coral dates back about 20,000 years. 
  • The Great Barrier Reef accounts for about 10% of the world’s coral. 
  • There are no atolls (ring-shaped coral reefs around a lagoon) in the Great Barrier Reef. There are about 440 atolls in other reefs around the world.
A large new coral growing on top of old coral
New coral grows atop dead coral skeletons.
  • The Great Barrier Reef has more than 30 reef bioregions, with different types of reef structures and wildlife in each one. 
  • 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).
  • Aboriginal Australian and Torres Strait Islanders have known about and recognized the importance of the Great Barrier Reef for thousands of years.  
A shipwreck on Australia's Great Barrier Reef
A shipwreck from above
  • It was the Englishman Matthew Flinders, the first to circumnavigate Australia by ship, who named the Great Barrier Reef. 
  • There are at least 800 ship and plane wrecks in the Great Barrier Reef area.  
  • Queensland has over 200 national parks, many of which include parts of or are adjacent to the Great Barrier Reef.  
Aerial view of white beaches on the Whitsundays
The Whitsunday Islands, famous for their white-sand beaches, are some of the most famous in the GBR
  • 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 the likes of Uluru and Sydney Harbour Bridge.
  • The Great Barrier Reef is home to over 1500 species of fish, 125 species of shark, ray, skate, and chimaera, 30 species of cetacean (marine mammals), 330 species of ascidians (sea squirts) and 500 species of algae or seaweed. 
  • 6 of the world’s 7 species of sea turtle, all of which are endangered, live on the Great Barrier Reef.  
Epaulette shark swimming by some coral reef
An epaulette shark on the GBR
  • 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.”  
  • Crocodiles, 7 species of frog, 118 species of butterfly, and 200+ species of bird also live near the reef.  
  • Humpback whales migrate from Antarctica to the Great Barrier Reef to breed from May to October.  
  • Fishing is allowed in 67% of the Great Barrier Reef Marine Park, but is strictly regulated.  
A pair of nautilus swimming by coral reef
The ancient nautilus lives on the Great Barrier Reef
  • Tourism to the Great Barrier Reef generates over AUD5 billion per year, with over 2 million visitors annually.  
  • 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.  
  • Many operators send divers to stay aboard platforms, or ships that are parked permanently on the reef, leading to an increase of diseases on those reefs.  
Some people snorkeling on a coral reef
Snorkelers on the Great Barrier Reef
  • 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. 
  • The Great Barrier Reef is slowly moving southward, and could reach as far as Tasmania within 300 years. 
  • There are several underwater “street views” of the Great Barrier Reef on GoogleMaps.  
  • 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.  
A section of coral reef that has been bleached
Bleached coral
  • The Australian government has a Reef 2050 Plan, but experts and UNESCO have expressed doubts that the plan will succeed in adequately protecting the Great Barrier Reef from destruction.