Did you know? Over half of NSW’s coastal wetlands have been lost since 1788. Unfortunately, even today, they are continuing to decline in health and extent, despite the many benefits they provide us. You can read more about why wetlands matter here. 

Threats to coastal wetlands in NSW include:

• Sea level rise and climate change. As sea levels and temperatures rise, and severe weather events become more frequent, the conditions coastal wetlands evolved to thrive in are changing quickly. While some wetland forms like mangroves have a natural capacity to raise themselves upwards (accretion) or retreat inland, sea level projections will overwhelm this adaptive capacity in some instances. We must restore wetlands now so they have time to build up sediment, provide them buffers so they can retreat inland, and engage in active coastal management to ensure sea level rise does not destroy these ecosystems.
• Inappropriate development. Inadequate planning legislation continues to allow developments in NSW that harm coastal wetlands. This includes through habitat clearing, acidic sediment runoff, the loss of habitat corridors, and blocking the natural retreat of coastal wetlands as sea levels rise.
• Invasive species. Especially once disturbed or degraded, wetlands are susceptible to invasion by non-native species. Both aquatic and terrestrial weeds can reduce the biodiversity, water purification, and habitat values of wetlands. Similarly, invasive animals such as cats, foxes, deer, pigs and invasive fish, can predate or outcompete native animals, while also destroying their habitat.
• Pollution: Although wetlands are excellent water purifiers, they are also vulnerable to pollution. While persistent toxic chemicals from industry continue to impact wetlands, today the biggest threats come from the runoff of acid-sulphate soils, nutrients, pesticides, herbicides, and organic matter. This pollution is primarily a consequence of altered floodplain hydrology and runoff from agriculture and development. In some coastal wetlands in NSW, the situation has gotten so bad that the water pH has become more acidic than vinegar or lemon juice.
• Unnaturally altered flows. Excessive upstream extraction, diverted watercourses, drainage channels, flood gates, dams and levees continue to severely damage coastal wetlands. These changes in catchment hydrology have led to the collapse of many systems across rural and urban environments alike. Coastal wetlands rely on adequate flows and a naturally regulated balance of fresh and saline (salty) water. Too little water, or an unnatural change in water salinity, can harm wetland vegetation and the animals that depend on them.

Case study – Saltmarsh

Scientists have predicted that, under most climate change projections, saltmarsh lacks the natural capacity to retreat quickly enough to keep pace with rising seas. In many instances, this has already led to the encroachment of retreating mangroves into saltmarsh, leading to further losses of these globally threatened ecosystems. To save saltmarsh and its' resident species, we must limit climate change and sea level rise, provide buffer space for coastal wetlands to retreat, and intervene to restore saltmarsh where they will be safe from retreating mangroves and rising seas.

Map of coastal wetland loss

To illustrate the impact these threats are having, we've made a statewide, interactive map showing just how much coastal wetland vegetation we've lost. To view or learn more about our interactive map, click here or on the image above.

The good news is that with enough will, NSW’s coastal wetlands can be restored in our lifetime. We need to:

• Conserve, rehabilitate, and responsibly manage what’s left.
• Restore and regenerate what we’ve lost.
• Allow and assist coastal wetlands to adapt to climate change, and retreat from rising seas.

Support our campaign to restore and conserve NSW's coastal wetlands here!