Queensland's Wetlands

Wetlands are an important resource

While wetlands are often under threat and falsely denigrated as infested swamps, they are a valuable resource for recreation, education and science.

By absorbing and slowly releasing floodwater, wetlands conserve water and provide a buffer against coastal erosion, storm surges and flooding.

Wetlands filter out excess nutrients and sediment from run-off which would otherwise go into creeks and rivers, and in coastal regions they are a nursery for varieties of fish and crustaceans.

Wetland plants shelter and provide habitat and roosting sites for countless animals and birds and are vital for the survival of many threatened species.

Inland wetlands, though sometimes dry, provide an important habitat for wildlife, especially waterbirds.

Both coastal and inland wetlands provide breeding sites for local waterbirds as well as habitat for migratory birds.

Wetlands are alive!

Wetlands support a diversity of plants and animals that depend on one another for food and shelter.

Algae and other wetland plants grow under water, providing food and oxygen for animals that live in and on the wetland. Around the shoreline, some plants grow partly in the water, storing food in their roots and bulbs. Sedges and rushes around the water’s edge provide roosting and nesting sites for birds. Grasses grow on the surrounding mudflats and in shallow areas. Marine wetland plants such as seagrass provide important habitat and food sources.

Fringing the wetland are trees such as melaleucas and river red gums which can tolerate water-logging. Birds and other animals find food among the wetland sedges and tea trees, especially in pools left behind when water levels drop.

Frogs and tortoises live in and around freshwater wetlands and some reptiles and insects spend part of their life cycle in wetlands.

River estuaries and swamps in tropical Queensland are important habitats for freshwater and saltwater crocodiles.

Many plants and animals have adapted to living in inland wetlands. After rain, waterbirds travel long distances to feed on fish and other creatures found in these temporary waterholes and lakes.

Threats to survival

For years, the role of wetlands in promoting a healthy environment was poorly understood. Lack of awareness of the role of wetlands has been the single greatest threat to their survival.

According to the Australian Department of Environment and Water Resources, about half of the nation’s natural wetlands have been destroyed since European settlement.

Experts believe the greatest threats to Queensland’s wetlands are:

• decisions made without coordinated planning and management of wetlands
• inadequate buffers between wetlands and surrounding lands
• changes to wetland drainage and water flow.

With more than 70 percent of Queenslanders now living within 40 kilometres of the coast, the pressures on coastal wetlands are immense. Some wetlands have been drained to provide land for agriculture or forestry, or reclaimed for urban development.

In the past, some wetlands were dredged for sand, and seagrass beds have been damaged by boat propellers. Dykes, ponded pastures and constructed barrages in coastal areas have affected the flow of saltwater into the wetlands, upsetting the natural balance.

Several wetlands have come under immense pressure from heavy metals, insecticides, fertilisers, sewage and other forms of pollution.

Traditionally, wetlands have provided reliable water supplies in drier areas, but water use, siltation and run-off have reduced the natural availability of water and adversely affected wetland wildlife.

While artesian water and bore drains have increased surface water availability and favoured species such as kangaroos in some areas, these artificial waters have not created the complex riparian habitat essential for maintaining wildlife throughout the landscape.

Flood control and water conservation works can affect wetlands. Some wetlands have been inundated to form water storages, while others have been damaged by works to prevent flooding and ‘improve’ drainage.

Fringing wetland plants have commonly been removed and as agricultural areas have expanded, wildfires have damaged some ephemeral wetlands, particularly where introduced drainage measures caused the wetland to dry out.

Introduced livestock and feral pigs grazing around wetland edges can damage fragile wetlands plants and cause sedimentation. Introduced plants have choked some wetlands and introduced fish have preyed on and destroyed native wetland species.

Coastal wetlands also face damaging natural threats, such as from cyclones and storm surges, and this becomes more of a problem where only a small amount of coastal wetlands remains.

Apart from direct threats, wetlands can also suffer from interference to the surrounding catchment. Increased run-off following clearing in wetland catchments can cause nutrient overload and excessive siltation.

Changing a river flow also affects wetlands. When a river is controlled, the floodplain wetland can be destroyed. Removing water from rivers can affect the natural flooding process which is crucial for temporary wetlands and the breeding cycles of some animals.

Wetlands in Queensland

Almost four percent of Queensland is permanently or periodically covered in water. Queensland’s 39 wetland types include about 400,000ha of mangroves, more than 600,000ha of saline coastal flats, and almost 300,000ha of intertidal flats.

Wetlands are found throughout Queensland, from the Gulf of Carpentaria and Cape York Peninsula in the north, along much of the east coast south to the Gold Coast, and inland to the semi-arid areas of the south-west.

Extensive seasonal wetlands around the Gulf of Carpentaria attract many birds and provide temporary homes for migratory birds. Large numbers of birds live on and around permanent lagoons along the east Queensland coast, especially during the dry season.

Tropical wetlands include the seasonally flooded fan palm forests, crater lakes and Eubenangee Swamp, which is one of the few remaining lowland freshwater tropical wetlands.

The central Queensland coast has many wetlands, from tea tree swamps in the Proserpine area to mangroves around Repulse Bay and Cape Palmerston.

Great Sandy Strait near Fraser Island has extensive mangroves and tidal flats which provide roosting and feeding habitat for migratory waterbirds.

In the south-east, the upper Noosa River, Pumicestone Passage and much of Moreton Bay are outstanding wetlands for nature, recreation and fish breeding.

Lake Jabiru on Moreton Island is the most extensive habitat for the threatened Oxleyan pygmy perch.

The Channel Country in the far south-west is one of arid Australia’s most important ephemeral wetlands. After heavy rains, slow-moving floodwaters of the Diamantina River and Cooper Creek create a vast wetland of meandering channels and floodplains.

Currawinya National Park, with the saline Lake Wyara and the freshwater Lake Numalla, is an internationally significant wetland. Lake Bindegolly to the north-west is an important waterbird breeding site.

Wetland Summary Information

For more wetland information based on a particular basin, NRM region or local government area.

Last updated: 22 May 2008