Bleached Corals

Preview These bleached corals in the Gulf of Mexico are the result of increased water temperatures.
(Emma Hickerson/NOAA)

What is coral bleaching? These white corals in the Gulf of Mexico’s Flower Garden Bank National Marine Sanctuary are bleached due to an increase in water temperatures, which causes corals to lose the microscopic algae that provide them with food. Bleaching spells trouble for coral reefs. Learn more in the Coral Reefs section.