Colourful and full of life, coral reefs support a great diversity of life. They require shallow seas with suitable conditions: temperature, wave exposure and water quality.

Reefs provide many resources for people, not least as marvels for divers to wonder at. They are under threat, but MCS is striving to reverse the destructive trends.

coral facts

• Coral reefs are built from the limestone remains of coral skeletons and coralline algae - but corals are not restricted to the tropics. They thrive in temperate seas, in the cold blackness of the deep oceans and even under polar ice. But in the absence of warm water and symbiotic algae they are unable to grow into reefs.

• reef action: The Semporna Islands Darwin Project is an initiative involving local communities in coral reef conservation in theTun Sakaran Marine Park, Sabah, Malaysia. The project is managed by the Marine Conservation Society.

  The basic ‘unit’ of a coral is the polyp - a small anemone-like animal. The branching, massive. plate-like or encrusting corals that build reefs are colonies of hundreds or thousands of polyps held together by soft tissue and the calcareous skeleton they secrete. Symbiotic algae (zooxanthellae) living within the tissues of corals are of fundamental importance in reef building.
• Innumerable habitat types, thousands of fish species and tens of thousands of invertebrates and algae combine on coral reefs to produce the highest biodiversity of all shallow water marine ecosystems.
• Healthy reefs have enormous potential for diving and recreation and boost the economies of many countries.
• Coral reefs act as natural self-repairing breakwaters, protecting adjacent land from storm-driven waves and reducing coastal erosion.
• They are rich fishing grounds for molluscs, crabs, lobsters, fish and other edible species. Many people depend on reef produce for their everyday needs.
• Resist the temptation to buy shells, corals, or other marine curios when on your holiday
  Reefs provide exotic non-food products such as shells for decoration and live fish and invertebrates for the aquatic trade.
• Certain reef organisms contain compounds with important pharmaceutical properties which can be used to develop sunscreens and powerful drugs.
• Some types of coral skeleton can be used as bone graft substitutes, for example to repair bones damaged by cancer. They are not rejected and are proving highly successful.