Coral Reefs
Despite covering less than 1 percent of the ocean floor, coral reefs are home to 25 percent of all fish species. Fish harvested from coral reefs feed tens of millions of people in developing countries and reef-related fishing, trade and tourism generates up to $30 billion annually, accounting for more than 15 percent of the GDP of 23 nations. Reefs also help protect more than 93,000 miles (150,000km) of coastline in 100 countries.