Description
The Great Victoria Desert (GVD) is the largest of Australia’s deserts, stretching from eastern Western Australia across the western half of South Australia. It is an active sand-ridge desert, consisting of many low and frequently jumbled sand-dunes, with playa lakes bordered by lunettes (crescent-shaped dunes). Creeks are few and rocky outcrops are scarce. Gibber plains are also present.
The GVD supports many vegetation types, including eucalypt open woodlands, mulga woodlands, acacia shrublands, casuarina and mallee shrublands and woodlands, and chenopod and samphire shrublands. Of note are the sparse woodlands of stately marble gums.
More than 15% of the Great Victoria Desert bioregion is held within reserves; with 8.5% of the Western Australian section of the bioregion held within the conservation estate. Reserves include Mamungari Conservation Park (SA), Yeo Lake Nature Reserve (WA), Neale Junction Nature Reserve (WA), Plumridge Lakes Nature Reserve (WA), and Great Sandy Desert Nature Reserve (WA). The Walalkara Indigenous Protected Area (IPA), Mt Willoughby IPA, Watarru IPA and Apara-Makiri-Punti IPA(?) are within the GSD.
The South Australian section of GVD is a declared UNESCO Biosphere Reserve, in recognition of its largely unaltered landscapes.
Geographical area
The Great Victoria Desert bioregion encompasses 420,000 square kilometres of land in the southern rangelands of Western Australia (52% of the bioregion) and the west of South Australia.
Climate
The climate of the GVD is arid, with variable and unpredictable rainfall that can fall in either summer or winter. The median annual rainfall (1890–2005) averaged across the GVD is 162 mm.
Desert communities
Anangu Pitjantjatjara Yankunytjatjara lands; Ngaayatjarra lands. Ernabella, Amata, Pipalyatjara, Oak Valley and Tjuntjuntjara.
Flora and fauna
Much of the GVD is covered by open woodlands with a grass understorey. The sandplains and areas between sand hills support hummock grasslands of hard spinifex (Triodia basedowii) with scattered eucalypts such as marble gum (Eucalyptus gongylocarpa) and large-fruited mallee (E. youngiana) or mulga (Acacia aneura). Sand dunes support spinifex with an overstorey of mallee, acacia and other shrubs. Gibber plains are normally almost devoid of vegetation but following rains they may be densely covered by flowering ephemeral species from the daisy, pea and amaranth families.
The GVD has an exceptionally high diversity of reptiles with 95 species recorded, 18 of which are of conservation significance.
Threatened species
The GVD bioregion supports nine threatened plant species and 24 threatened or vulnerable animal species, including:
- Greater bilby (Macrotis lagotis)
- Crest-tailed mulgara (Dasycercus cristicauda)
- Brush-tailed mulgara (D. blythii)
- Southern marsupial mole (Notoryctes typhlops)
- Sandhill dunnart (Sminthopsis psammophila)
- Warrana/tjakura/Great Desert Skink (Liophilis kintorei)
- Princess parrot (Polytelis alexandrae)
- Chestnut breasted whiteface (Aphelocephala pectoralis)
- Australian bustard (Aredeotis australis)
- Scarlet-chested parrot (Neophema splendida)
- Grey falcon (Falco hypoleucos)
- Mallee fowl (Leipoa ocellata)
Key threats
Introduced predators such as red foxes and feral cats have been a primary cause of the extinction of small- to medium-sized mammals across Australia’s arid inland. Along with wild dogs, they continue to pose significant threats to mammals, reptiles and ground-dwelling birds across all of Australia’s desert ecosystems.
Introduced herbivores such as camels, donkeys, horses and rabbits cause significant damage to desert ecosystems through overgrazing, particularly around water sources where they tend to congregate in dry times. Camels foul waterholes and have significant impacts upon fragile salt lake and freshwater ecosystems.
Of all the invasive species, buffel grass (Cenchrus ciliaris) poses the greatest threat to Australia’s desert ecosystems as it can quickly come to dominate the ground layer of vegetation. It burns hotter and more quickly than the native grasses it replaces. Buffel grass invasion in combination with larger and more intense wildfires driven by climate change have the potential to devastate the biodiversity of arid ecosystems.
Vegetation clearing for mining exploration is a potential threat to ecosystems in the GVD.
Project activities
Buffel Free GVD Initiative (Spinifex Land Management Rangers)