Some refer to coral reefs as the “rainforests of the ocean” because of their importance to marine ecosystems. Even though coral reefs make up only one-tenth of the ocean, 25% of all known marine species live there. According to the World Resources Institute, coral reefs generate about $1.6 billion for the Indonesian economy yearly. However, increased global warming, ocean acidification and over-fishing are causing a decline in coral reefs across the world. This may lead to irreversible damage to the marine ecosystems that so many species, including humans, depend on.