The state and trends of the living (biotic) and nonliving (abiotic) environment in the coastal zone are the result of both historical and contemporary pressures, and our attempts to ameliorate these pressures. The state of most coastal biological components is in decline, particularly habitats and species that overlap with coastal land use. Much of Australia’s native coastal vegetation has been lost to clearing, soil quality has diminished, and island flora and fauna suffer from invasive species. The dynamic land–water interface of sizeable stretches of coastline has been altered from a natural state by development, resource extraction, invasive species and recreational use. Several estuaries and bays around the nation are centres of urban, industrial and agricultural activity, and the pressures from such intense development often reduce water quality, and change the fish and invertebrate communities that use these critical coastal features.

The distribution of threatened species around the nation is generally related to the distribution of the human population and the intensity of our activities. The species group of most concern is migratory shorebirds, which are declining because of habitat loss and impacts on critical parts of their migratory route in Australia and overseas. This is occurring despite protection in Australia, and looks to continue unless multilateral management can be achieved. Saltmarshes are also in a poor state. Their extent around urban centres is a fraction of their pre-European settlement state, and they are now subject to further clearing and drainage, and the encroachment of mangroves. Saltwater crocodiles are doing well because they are protected from harvesting, and their predominantly northern distribution spares them from the bulk of pressures associated with coastal development. Vital ecological processes are in a poor state nationally as a result of multiple pressures on coastal ecosystems.

Coastal heritage requires greater documentation, particularly in relation to Indigenous heritage, which is currently under-represented. There have been recent advances in this field, including recognition in the Great Barrier Reef outlook report 2014, and incorporation of threat and risk assessment into the Marine Estate Management Act 2014 of New South Wales, but further progress is needed.