Coral reefs are primarily found in tropical and subtropical ocean waters, mostly between 30° north and 30° south of the equator where the water is warm and sunlight can penetrate. These reefs thrive in shallow, clear waters up to about 150 feet (45 meters) deep because they depend on sunlight for the symbiotic algae living within them
. More than half of the world's coral reefs are concentrated in six countries: Australia, Indonesia, Philippines, Papua New Guinea, Fiji, and the Maldives. The Indo-Pacific region, including the Red Sea, Indian Ocean, Southeast Asia, and the Pacific, accounts for over 90% of global coral reefs, with significant reef areas also found in the Atlantic and Caribbean
. Notable coral reef locations include:
- The Great Barrier Reef in Australia, the largest reef system in the world
- The Philippines, with one of the largest reef areas in Southeast Asia
- The Raja Ampat Islands in Indonesia, known for the highest marine biodiversity
- Florida Reef Tract along the coast of Florida, the third largest barrier reef system globally
- Bermuda, which hosts the northernmost coral reef system due to warm Gulf Stream currents
- The world's northernmost and southernmost coral reefs are found in British Columbia, Canada, and Lord Howe Island, Australia, respectively
In summary, coral reefs are found mainly in warm, shallow tropical and subtropical waters around the equator, with major reef systems distributed across the Indo-Pacific and Atlantic regions
