Coastal saltmarsh has been listed as an Endangered Ecological Community in New South Wales. Recent research has highlighted the importance of coastal saltmarsh as a source of nutrition for fish, a nocturnal feeding habitat for microbats, and a roosting habitat for several species of migratory shorebirds. Since European colonisation, coastal saltmarsh has been reclaimed for agricultural, residential and industrial use, and the past five decades has seen a consistent replacement of saltmarsh by mangrove throughout SE Australia. Analysis of data from the network of Surface Elevation Tables in NSW and Victoria has demonstrated a link between the replacement of saltmarsh by mangrove and relative sea-level rise. However, this is not the only potential climate change impact, given the strong inverse relationship between saltmarsh diversity and temperature in Australia. Saltmarsh species diversity increases with latitude, with temperature explaining more than 80 percent of variability in saltmarsh species numbers between bioregions. A southward translation of climatic zones in Australia would pose significant challenges to the preservation of saltmarsh diversity at a continental scale.