Unesco's meeting in Bonn will decide whether to list the Great Barrier Reef, which has lost half its coral in the past 30 years, as "in danger". The Australian government fears the move would affect its A$6 billion-a-year tourism industry.
The Great Barrier Reef (GBR) is a 2,300km-long ecosystem off the coast of Queensland made up of thousands of reefs and islands made out of over 400 types of hard and soft coral. It is the home of 1,500 species of fish and 4,000 types of mollusc. It is also the habitat of species such as the dugong (sea cow) and the large green turtle, which are threatened with extinction.
GBR was nominated in 1981 by Unesco (United Nations Educational Scientific and Cultural Organization) for inclusion in the World Heritage List.
It has economic significance for regional communities in Australia because some uses, such as marine tourism and finishing, depend on an intact ecosystem.
The 2009 Outlook Report identified the long-term challenge for it's conservation was associated with climate change, and such factors as the declining water quality from land based sources, and the loss of coastal habitats.
The 2014 Outlook report noted sea temperatures were expected to continue to rise, with gradual ocean acidification. More intense weather events should also be expected.
* The proposal to exploit the underground coal reserves in the Galilee basin in Queensland - an area of underground coal the size of Briitain - is controversial because the Abbot Point port would be expanded, and the passage of container ships along the narrow lanes would put pressure on the reef. Conservationists also argue that carbon emission from exporting the coal should be taken into account when assessing the project.
* A proposal to classify the GBR as "in danger" could restrict the funding need to develop the Galilee basin coal reserves because most major financial institutions have signed up to the Equator Principles, a set of standard that deter the funding of projects that harm world heritage sites.
Date written/update: 2015-05-22