Gawler bioregion
Gawler is an interim Australian bioregion located in South Australia. It has an area of. Gawler bioregion is part of the Tirari–Sturt stony desert ecoregion.
Geography
The landscape consists of rolling terrain, rocky hills, plains, and salt-encrusted lake beds. Ephemeral salt lakes, including Lake Torrens, Lake Gairdner, Lake Macfarlane, Lake Everard, Lake Gilles, Lake Harris, and Lake Acraman, cover extensive areas. The Gawler Ranges lie in the southwestern portion of the bioregion. The Flinders Ranges bound the bioregion to the east. In the southeast the bioregion extends to the Spencer Gulf.Climate
The Gawler bioregion has an arid climate. Rainfall is predominantly in the winter, with a spatially-averaged median of 169 mm annually. Rainfall is higher along the southern edge of the bioregion where it transitions to the Mediterranean climate Eyre Yorke Block.Flora and fauna
The main plant communities are spinifex grasslands, open woodlands, and chenopod shrublands.Endemic plants of the Gawler Ranges include Acacia toondulya, Gawler Ranges greenhood, Gawler Ranges hop-bush, and Gawler Ranges grevillea. The Lake Acraman button-daisy is endemic to gypseous soils of the lake flats.
Native mammals include red kangaroo and western grey kangaroo. Threatened species include the yellow-footed rock-wallaby in the Gawler Ranges and the plains rat in the stony plains.
Threatened birds native to the bioregion include the western grasswren in the stony plains and chenopod shrublands of the Gawler ranges, the western slender-billed thornbill in chenopod shrublands, and malleefowl in mallee woodlands and shrublands.
The Pernatty knob-tailed gecko is endemic to the bioregion. The Lake Eyre dragon is a lizard which inhabits the salt flats of Lake Torrens, where it lives in cracks in the salt crust.
The ephemeral lakes are important breeding grounds for water birds, including silver gull, Australian pelican, black swan, Caspian tern, red-necked avocet, red-capped plover, and banded stilt.
The ephemeral freshwater rock-holes present in exposed granite outcrops are a habitat for unique communities of freshwater invertebrates that are otherwise rare in the region.
Land use
Most of the bioregion, except for the salt lake beds, is used for livestock grazing, mainly sheep with some cattle.The main towns are Whyalla, Port Augusta, Roxby Downs, and Woomera. Mining of copper, uranium, and gold at Olympic Dam mine is a major source of revenue for the local economy. Iron ore is mined around Iron Knob.
Subregions
Gawler bioregion consists of eight subregions:- Myall Plains –
- Gawler Volcanics –
- Gawler Lakes –
- Arcoona Plateau –
- Kingoonya –
- Torrens –
- Roxby –
- Commonwealth Hill –