Geographical Distribution: Tropical and sub-tropical oceans around the world.
Often referred to as the “rainforests of the seas”, shallow-water coral reefs form one of the most diverse ecosystems on Earth. Although they cover less than 0.1% of the world’s ocean surface and about half of France’s surface, they are home to at least 25% of all marine species.
Coral reefs are sensitive ecosystems, in part because of their sensitivity to water temperature. They are threatened by climate change, ocean acidification, explosive fishing, sunscreen use, overexploitation of reef resources, and harmful land use practices such as urban and agricultural waters, and water pollution.
Corals are ancient animals associated with jellyfish and anemones. Each coral is known as a polyp, a very small and simple organism consisting mostly of a single stomach with a tentacled mouth at the end. Thousands of polyps with similar characteristics live together and form a coral colony.
Reefs form in shallow areas where only sunlight can access, due to the relationship between coral and algae. Various species of microscopic algae, also called symbiodinium, live inside the coral, providing nutrients to the coral and helping the coral grow faster. In many ways, corals that make up reefs are animals that move like plants because they stay in one place and get their energy from the sun.