Coral reefs provide a barrier for coastal areas by breaking the waves of severe storms. They help prevent coastal erosion, flooding, and the loss of property along the shore. Many coastal communities also benefit from the tourism and fishing generated by coral reefs. Like tropical rainforests, the rich biodiversity of the coral reef ecosystem may serve as a source for unique chemicals with medicinal properties, just waiting to be explored and discovered. Coral itself can be used in human bone grafts.
Sponges growing on reefs can provide virus-fighting agents.
Endangered Coral Reefs For all their splendor and biodiversity, the world's coral reefs are endangered. Fishermen stun tropical fish by squirting cyanide into the reefs. This technique enables them to capture live fish for aquariums. In the process, the cyanide poisons both the reef and many of the invertebrate species living in its ecosystem. Sewage, fertilizers, and pesticides all originate on land and often run off into the ocean.