Warnings over the poor state of the world's coral reefs have become more frequent in the past decades as pollution, increasing pressure on fish stocks, and the effects of global warming on the marine environment – in the form of higher sea temperatures and slightly elevated levels of acidity in the ocean – have taken their toll.
Last year, scientists estimated that 75% of the Caribbean's coral reefs were in danger, along with 95% of those in south-east Asia. That research, from the World Resources Institute, predicted that by 2050 virtually all of the world's coral reefs would be in danger.
This decline is likely to have severe impacts on coastal villages, particularly in developing countries, where many people depend on the reefs for fishing and tourism. Globally, about 275 million people live within 19 miles of a reef.