Ecosystems · Oceania and Southeast Asia

Great Barrier Reef And Coral Triangle

The richest marine life on Earth, built by tiny corals.

The Great Barrier Reef off north-eastern Australia is the largest coral reef system in the world. Further north, the Coral Triangle around Indonesia, the Philippines and Papua New Guinea has the highest marine biodiversity on the planet.

Reefs are built over thousands of years by tiny animals called corals.

The Landscape

Shallow, warm, clear water allows corals and the algae living inside them to thrive. The reef includes thousands of individual reefs, cays and lagoons, with seagrass beds and mangroves nearby.

Who Lives Here

Clownfish shelter among anemones, Green Sea Turtles graze seagrass, and Manta Rays glide through the channels. Giant Clams, reef sharks and Humphead Wrasse are among thousands of other species.

Through The Year

Water is warmest in the southern summer, when marine heatwaves can cause coral bleaching. Many corals spawn together on a few nights after a late-spring full moon. Cyclones can hit in summer.

Pressures And Care

Rising ocean temperatures, which cause mass bleaching, plus poor water quality, crown-of-thorns starfish, cyclones and overfishing, are the main pressures. Cutting emissions and improving water quality are the most important steps.

Visiting Well

Never touch or stand on coral, use reef-safe sun protection, choose accredited operators, and do not take shells or coral.

Look for

Green Sea Turtle
Clownfish
Manta Ray
Giant Clam
Humphead Wrasse

Often a good time to visit: June, July, August, September, October. Conditions vary from year to year and place to place.

Related habitats

Coastal