Community Description

• Coastal Saltmarsh in the New South Wales North Coast, Sydney Basin and South-east Corner Bioregions is an Endangered Ecological Community associated with the intertidal flats on the shores of estuaries and lagoons (including when they are intermittently closed) along the NSW coast.¹
• Characteristic plants within Coastal Saltmarsh include:
• sedges such as Baumea juncea, Isolepis nodosa, Juncus krausii (Sea Rush),
  
• tidal flat specialist plants such as Selliera radicans, Samolus repens (Creeping Brookweed), Sarcocornia quinqueflora (Glasswort, Samphire), Suadea australis (Austral Seablite) and
  
• grasses such as Triglochin striata (Streaked Arrow Grass), Zoysia macrantha (Coast Couch) and Sporobolus virginicus (Sand Couch).¹
• Species composition varies with elevation, Sarcocornia quinqueflora (Glasswort, Samphire) dominates at lower, more frequently inundated levels, while Sporobolus virginicus (Sand Couch) likes the mid area and Juncus krausii (Sea Rush) prefers the upper saltmarsh areas.

Importance of Saltmarsh

Saltmarshes are habitats for communities of salt-tolerant vegetation, a wide range of invertebrates, and low-tide and high-tide visitors such as fish, waterbirds and mammals.

Saltmarsh is important as it:

• Plays an essential role in estuarine foodchains as they are an important food source for juvenile fish and crustaceans.
• Acts as an ecological buffer balancing nutrient and organic matter content between dryland vegetation communities, mangroves and water systems.
• Provides a protected environment for marine and terrestrial organisms.
• Protects coastal shorelines.
• Traps and binds sediment.
• Improves and maintains water quality through filtration.
• Supports commercial fishing industry by acting as a food source and nursery.
• Provides places for bird watching.

Habitat Requirements

Landform: Occurs on the Coastal mud flats that are just above, or level with, Mean High Water Mark and are regularly inundated by king tides.

Distribution: Occurs in localised areas along the NSW Coast, within sheltered coastal lagoons and bays.¹ Locally this community occurs in small areas on the margins of coastal estuaries, creeks, and lakes.

Soil: Fine-grained dark coloured sediments usually in excess of 2 metres deep. Coastal Saltmarsh is most commonly found on estuarine soils associated with the Mangrove Creek or Cockle Bay Soil Landscapes of the Central Coast.²

Hydrology: Saline, waterlogged and periodically inundated areas associated with tidal flats which are regularly inundated by king tides.

Where this community can be found

Gosford: Patonga Creek, Cockle Bay, Kincumber, Davistown, Empire Bay.

Wyong: At the extremity of the mouth of Wyong River at Rocky Point; around the foreshores near Toukley Golf Course; and along the foreshores at Charmhaven.

Lake Macquarie: West of Lambton Parade, Swansea Heads, north end of Park Street at Swansea; and at Five Islands Reserve, Teralba.

Threats

• Reduction in size of areas of Coastal Saltmarsh.
• Fragmentation into smaller or more isolated occurrences.
• Pollution (including household / garden waste, oil, chemicals).
• Infilling and earthworks associated with development or waste disposal.
• Modified tidal flows by installation of artificial structures.
• Weed invasion.
• Damage such as grazing and trampling by domestic and feral animals.
• Human disturbance (eg foot tracks, vehicle, 4WD, BMX pushbike, horse riding or trail bike damage).
• Altered salinity (by discharge of stormwater into or near salt marshes).
• Invasion by mangroves.
• Rubbish dumping.
• Climate change and associated sea-level rise.
• Altered fire regimes.

• Clearing of native vegetation.
• Invasion of native plant communities by exotic perennial grasses.
• Alteration to the natural flow regimes of rivers, streams, floodplains and wetlands.

• Human caused climate change.

Management Issues

• Minimising and controlling human disturbances such as pedestrian and vehicle access and pollution from rubbish, chemicals, oils, freshwater runoff and nutrient / fertiliser input.
• The expansion of mangroves in Coastal Saltmarsh areas.
• Alteration to natural hydrological regimes may result in changes to the extent and composition of this community.
• Coordinating planning and management practices for Coastal Saltmarsh across whole catchments.

Useful Web links:

• Department of Environment and Climate Change – www.dec.nsw.gov.au

Further Reading:

• Keith, D. (2004) Ocean Shores to Desert Dunes: The Native Vegetation of New South Wales and ACT. Dept of Environment and Conservation (NSW).
• Bell, S.A.J. (2002) The Natural Vegetation of the Wyong Local Government Area, Central Coast, New South Wales.      Vegetation Community Profiles. Final Report to Wyong Shire Council.
• Bell, S.A.J. (2004) The natural vegetation of the Gosford Local Government Area, Central Coast, New South Wales:    Vegetation Community Profiles. Final Report to Gosford City Council.
• National Parks and Wildlife Service (2003), Lower Hunter and Central Coast Regional Environment Management
  Strategy Vegetation Survey, Classification and Mapping: Lower Hunter and Central Coast Region. CRA Unit, National Parks and Wildlife Service, Hurstville.

Bibliography:

1. C.L. Murphy Ed. (1993) Soil Landscapes of the Gosford/Lake Macquarie 1:100,000 sheet, Soil Conservation Service of NSW.
2. NSW Scientific Committee (July, 2004) – Final determination to list Coastal Saltmarsh in the NSW North Coast, Sydney Basin and South East Corner bioregions as an Endangered Ecological Community.