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Ocean life

Coral bleaching

Coral bleachingCoral bleaching The National Oceanographic and Atmospheric Administration (NOAA) in the US has announced that the rising temperature of ocean waters has triggered coral bleaching across tropical parts of the Pacific, Indian and Atlantic oceans. Corals all over the world are in danger of being wiped out. Even though they cover only 0.1% of the sea bed, coral reefs, often called the “rainforests” of the ocean, are home to 25% of ocean species, which rely on them for their food. Corals are vital to ocean ecosystems, with even many non-reef species dependent on them. Most open-ocean fish, such as tuna, start their lives as larvae feeding in the waters of coral reefs. The disappearance of coral would have devastating effects on ocean life.

Corals owe their colours to the presence of algaeCorals owe their colours to the presence of algae


A coral reef is is formed from the hard skeletons of tiny animals: coral polyps, or corals for short. They live together in colonies of millions of individuals. Corals are marine invertebrates, related to sea anemones and jellyfish. Each measures only a few millimetres across. Algae called zooxanthellae actually live inside the bodies of the corals. In return for providing them with a habitat, the corals receive nutrients from the algae.

The Maldives lost about 90% of its reefs during the 1998 global coral bleaching event.

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