Mangrove forests are very productive ecosystems and of major ecological and economic importance. Clearing and development continue to be a major threat while only 8 per cent of mangroves are in protected areas. A threat to saltmarshes in developed areas is land reclamation. Extensive areas have been filled for ports, marinas, canal estates and urban and industrial sites. The total loss of saltmarshes in Australia is highly significant as habitat although it has not been great in area, with most loss concentrated in the south-east where the initial area was small.
Coral reefs are among the most productive, diverse and complex ecosystems in the world.
They are also under global threat. It is estimated that around 70 per cent of all the world's coral reefs are degraded in some way. This decline in the world's coral reefs has made the conservation of Australia's reefs of growing importance. Coral reefs are well represented in marine protected areas. Although most reefs are still in a relatively good condition, recent comparisons of several sites in the GBR show major changes have occurred to some of the reef flats over the last 40 to 100 years.