Coral Triangle

Total area: 2.3 million sq. miles
Reef building coral species: 600+
Reef fish species: 3000+
Marine mammals: 22
Sea turtle species: 5


The Coral Triangle is defined as the global epicenter of marine species diversity and is one of the top priorities for marine conservation. This magnificent region of the ocean covers an area of 5.7 million km2 and contains more than one-third of all the world’s coral reefs. It harbors more than 600 species of reef-building coral, or 75% of all known coral species, and over 3,000 species of reef fish. It also holds nearly 75% of the world’s mangrove species, over 45% of seagrass species, 58% of tropical marine mollusks, five species of sea turtles and at least 22 species of marine mammals also occur in the region – an astounding level of diversity concentrated in less than 1% of the world ocean’s surface area. Moreover, large numbers of these species occur nowhere else, including 97 species of reef fishes endemic to Indonesia, and more than 50 in the Philippines.

In broad geographical terms, the Coral Triangle includes portions of two biogeographic regions and encompasses East Timor, Indonesia, Malaysia (Sabah), Papua New Guinea, Philippines and Solomon Islands. Indonesia and the Philippines together hold a massive 77% of the regions’ coral reefs.


  • Blast Fishing
  • Fishing with poisons
  • Runoff and sedimentation
  • Sewage
  • Mining of reefs

Coral reefs and other marine habitats within this region are severely threatened by human activities. Over 150 million people live within the Coral Triangle, of which an estimated 2.25 million are fishers that depend on marine resources for their livelihood. The most pervasive threats are overfishing, threatening 64% of Southeast Asia’s reefs, and destructive fishing practices, threatening two-thirds of the reefs in the Philippines, Malaysia and Taiwan, and 50% of the reefs in Indonesia. Sedimentation and pollution associated with coastal development and changes in land use also put 37% of the regions reefs and marine habitats at risk.

 Page 2 | Coral Triangle: Conservation in Action