Arcoona Lakes


Site description (2016 baseline):

Site location and context
The Arcoona Lakes lie between Woomera and Roxby Downs in the central north of SA, ~500 km north of Adelaide. The climate is arid with erratic, variable rainfall (annual average ~150 mm at Roxby Downs and ~165 mm at Woomera).  The Arcoona Tableland, on which the lakes occur, has an area of ~10 000 km2. The lakes are diverse in their hydrology and water chemistry as a result of local catchment characteristics and provide a diverse array of sites. Some of the wetlands are large, shallow and highly saline, providing rich ephemeral shorebird habitat. Others provide deep (4-7 m) freshwater habitats which remain for several years following filling. By their nature, these ephemeral wetlands fill and remain inundated only after well above average rainfall.

Key biodiversity
These intact natural wetlands fill irregularly from local rainfall, providing great pulses of productivity to nomadic desert water birds. The extensive and diverse habitat supports the globally near-threatened Blue-billed Duck, large numbers of congregatory waterbirds such as Freckled Duck, Banded Stilt, Pink-eared Duck, Grey Teal, Hardhead, plus others, along with nesting habitat for biome-restricted terrestrial species such as the Bourke's Parrot.

Habitat and land use
The Arcoona Tableland, on which the lakes occur, consists of dissected stony tablelands and plains with mainly low open shrublands dominated by saltbush Atriplex and bluebush Maireana but almost no trees (apart from significant fringing Melaluca pauperiflora surrounding the lakes). By their nature, these ephemeral wetlands fill and remain inundated only after well above average rainfall, but these wet/dry cycles produce massive resource pulses, providing nomadic waterbirds with extensive feeding and breeding habitat, otfen at times when this is unavailable in other parts of the continent. This IBA incorporates the following 13 wetlands: Coorlay Lagoon, Chances Swamp, Lake Mary, Lake Bessie, Purple Lake, Purple Swamp, Red Swamp, Lake Koolymilka, Lake Echo North, Lake Echo South, Lake Campbell, Arcoona Lake and Lake Richardson. It has a combined area of 12,000 ha, which takes in the wetlands and fringing riparian habitats.

Pressure/threats to key biodiversity
A likely significant future impact is the construction of the infrastructure for expansion of the nearby Olympic Dam Copper/Uranium Mine.  An economic mineralisation of Copper/Uranium also exists at Coorlay Lagoon and could become a significant mining development in the future.
Otherwise Climate Change resulting in fewer, or more intense, rainfall events?
Human Recreation, limited mainly to Lake Mary.  
Changes in pastoral stocking rates may also result in impacts on hydrology and vegetation surrounding the wetlands.


Protected areas
None

Land ownership
Most wetlands lie on 'Roxby Downs, Purple Downs and Andamooka Pastoral Leases' (primary lLessee BHP Billiton, Olympic Dam, recently subleased to the Kokatha People -the local Native Title holders). 
Remainder on Arcoona Pastoral Lease - (lessee Collinsville Pastoral) and Wirraminna Pastoral Lease (lessee Inglewood Proprieters Pty Ltd). 
Additionally, the Australian Defence Force operates the Woomera Prohibited Area on the western part of the area in question - a military testing range.


Site access / Land-owner requests
The Woomera Prohibited Area covers part of the area.  Public access is not possible in these areas without a permit from the Australian Defence Force. Access to the remaining areas is organised by prior consultation with local station managers.

Acknowledgements
Marie and Leo McCormack (former Roxby Downs/Purple Downs Station managers), Peter Paisley, John Read. The Kokatha Peoples.


Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Arcoona Lakes (Australia). Downloaded from https://datazone.birdlife.org/site/factsheet/arcoona-lakes-iba-australia on 23/12/2024.