Most reef-building corals are found in warm, tropical and subtropical waters between 30° N and 30° S latitudes, indicated here with red dots. Coral reefs around the world are threatened by a variety of forces, and destruction of reefs is on the rise.

NOAA estimates that 75% of coral reefs worldwide are threatened by human activities or environmental changes. The two graphs below show the percentage of coral reefs already destroyed and the threats facing those that remain. Overfishing alters the community makeup, disrupting important relationships that keep the reef alive and healthy; heavy nets can also directly damage coral reefs themselves. Coastal development can add sediment to water, making it cloudy; in some areas, coral reefs are actually mined for limestone building materials. Pollution, whether from land or sea (ships), can directly harm coral as well.