Corals are tiny animals that live in large communities made up of individual polyps that secrete a calcium carbonate substance that hardens and builds up to form the reef structure over time. There are different types of corals, such as brain corals and fan corals, that form different types of structures. The coral polyps live symbiotically with algae that provides them with their food. Disease, temperature extremes and pollution can cause corals to expel the algae, leaving only the white calcium carbonate skeleton behind, an event called coral bleaching. Coral bleaching is a worry with global warming heating up the oceans and carbon dioxide causing the oceans to acidify. Coral reefs are important ecosystems because they support larger communities of fish, mollusks, crustaceans and other sea creatures.
Scientists on a 30-day expedition off the coast of Ecuador have mapped two coral reefs and two seamounts more than 1,000 feet beneath the ocean surface.
Every austral summer, Rangiroa and Tikehau atolls in French Polynesia host a mysterious assembly of female great hammerhead sharks — a critically endangered and typically solitary species.
The unprecedented water temperatures — reaching up to 95 degrees Fahrenheit in some places — could intensify storms and hurricanes in the Sunshine State.
Nature's red flag is the eerie white glow of one of the ocean's most biologically rich ecosystems.
Frequently mistaken for discarded piles of beach trash, ropelike sea whips are a type of colorful coastal coral.
Hot water is killing Florida's coral reefs. But it's not the only factor bleaching them white.
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