The Northern and Yorke region contains a diversity of wetland ecosystems. These ecosystems are critical to improving water quality, regulating water availability and the conservation of biodiversity. Find out more about the wetlands in our region.
What are wetlands?
Wetlands are areas that are seasonally or permanently waterlogged or inundated. This includes natural wetlands and those that are constructed to improve water quality.
Why wetlands are important
Wetland ecosystems are important because of the services they provide such as:
- improving water quality through the capture, retention and breakdown of excess nutrients, sediments and pollutants
- improving seasonal water availability and reducing erosion through the capture and slow release of water
- carbon storage within the soil and living plants
- providing critical habitat for native species (many of which are threatened and restricted to such ecosystems)
- supporting recreational activities, tourism and cultural heritage.
Wetlands in our region
The majority of wetlands within the Northern and Yorke region are naturally saline and are varying in environmental condition.
The salt lakes located in Dhilba Guuranda-Innes National Park are in excellent condition and are without doubt the best examples of salt lake systems on Yorke Peninsula. The ‘heel’ of Yorke Peninsula (near the township of Yorketown) is characterised by over a 100 circular salt lakes. Very little native vegetation in this area remains due to clearance. Further north, toward the township of Minlaton, is the last remaining forest of Eucalyptus camaldulensis (Red Gum) which is located in a seasonally inundated flat.
Inland wetlands are sparsely distributed over the remainder of the Peninsula, but more saline lake systems are found further north starting at the township of Lochiel. A band of salt lakes located on the Condowie Plains runs parallel to the Hummock and Barunga Ranges. These salt lakes are in agricultural lands that are largely cleared. One of the largest lakes, located near Lochiel (Lake Bumbunga), is a source of gypsum. This band of salt lakes terminates near Crystal Brook in the north.
Several fresh water bodies are located in the Southern Flinders Ranges, with Beetaloo Reservoir contained in Beetaloo Valley being one of the most prominent. Nelshaby Reserve Reservoir near Port Pirie is used as a secondary water supply and contains significant aquatic and terrestrial habitats.
Wetlands of National Significance in our region
There are seven wetlands of National Significance in the Northern and Yorke Region.
- Upper Spencer Gulf: an inverse estuary containing shallow, warm saline waters. The area is charactarised by intertidal mangrove forests, tidal sand and mud flats, with some areas of shingle and sandy beaches. The mud flats are dissected by a network of tidal channels including Chinaman Creek, First-Seventh Creek, Port Davis Creek and Fisherman Creek. Below sea level, extensive shallow seagrass meadows give way to a silty sea floor in deeper waters.
- Innes Salt Lakes: low-lying open saline lakes with established buffer vegetation and dense borders of samphire species around the waters edge. They are excellent examples of a larger salt lake system within Dhilba Guuranda-Innes National Park. Inneston Lake has one of the few examples of living stromatolites in the State.
- Clinton: Consists of a mangrove/samphire estuarine area with many large tidal channels fringed by mangroves. The Wakefield River is the only major drainage channel in the area and the only major input of freshwater into the tidal flat Gulf system. The hinterland consists of alluvial fan deposists with small creek gullies. These creeks either fan out onto the tidal flats, depositing red clay loam and gravel on the surface, or continue across to the sea.
- Point Davenport: A semi-stranded lagoon that enters the sea through a tidal inlet that is continually undergoing change as a result of a developing sand spit which separates the lagoon from the sea.
- Gum Flat: Containing the only remaining seasonally flooded River Red Gum forest on the Yorke Peninsula. The site is a valuable open space area adjacent to the township of Minlaton and is used for passive recreation.
- Native Hen Lagoon: Fringed by remnant South Australian Swamp Paper-bark. It is a linear wetland with a dense border of Melaleuca on the northern-eastern side. Sedge lands form thick tussocks by the waters edge.
- Wills Creek: Coastal environment consisting of two tidal creeks (Wills Creek and Shag Creek) which form shallow estuaries at Mangrove Point. Mangrove forests line the coast and are dissected by numerous small tidal channels which provide effective drainage when the tide recedes. Salt evaporation ponds are located nearby.