Description
The Great Sandy Desert (GSD) lies between the Kimberley and Pilbara regions in the north of Western Australia. It contains vast areas of red sand plains and dunefields, many of which are longitudinal, as well as scattered rocky outcrops. Surface creeks are few. There are extensive chains of salt lakes associated with ancient buried river systems.
Much of the GSD is covered by spinifex grassland that contains abundant shrubs of acacia and grevillea. These shrubs tend to be more dense in the north of the GSD, where the climate is more monsoonal. The rocky uplands support acacia shrublands. Bloodwoods and desert oaks are scattered throughout.
The permanent freshwater of Paruku (Lake Gregory), which lies on the border between the Great Sandy and Tanami deserts, is one of Australia’s most important inland wetland systems for migratory shorebirds and waterbirds.
Around 3% of the Western Australian section of the GSD bioregion is within conservation estate. The Paruku Indigenous Protected Area (IPA) borders the GSD and Tanami deserts; the Warlu Jilajaa Jumu IPA extends across 1.6 million hectares of the north-west of the GSD; and the Kiwirrkurra IPA extends across the sand hill country of the GSD and Gibson Desert. The Nyangumarta Warrarn IPA extends from the coast at Eighty Mile Beach and into the GSD and contains the Walyarta Conservation Park and Kurriji Pa Yajula Nature Reserve.
Geographical area
The Great Sandy Desert bioregion extends across 390,000 square kilometres of Western Australia and the Northern territory, with 75% of the bioregion in central northern WA, and 25% in the southern NT.
Climate
The GSD has an arid, tropical climate in the north grading to temperate–subtropical in the south. The influence of the monsoon is apparent in north-western part of the region. As with all Australian deserts, rainfall is highly variable and unpredictable. Median annual rainfall (1890–2005) averaged across the entire GSD is 223 mm.
Desert communities
Martu and Pintubi lands, with Kakatju and Walmajari in the north. Jigalong, Punmu, Kunawarritji, Balgo, Mulan.
Flora and fauna
The vegetation of the northern GSD is mainly open hummock grasslands of soft spinifex (Triodia pungens) and feathertop spinifex (T. schinzii) with an overstorey of scattered desert oak (Allocasuarina decaisneana), native walnut (Owenia reticulata) and bloodwoods (Corymbia spp.). Further south, the trees are replaced by shrubs of acacia and grevillea, including Wickham’s grevillea (Grevillea wickhamii) and silver-leaf grevillea (G. refracta). Upland areas have Acacia pachycarpa over soft spinifex while the salt lakes are surrounded by samphire and melaleuca shrublands.
Seventy-three species of waterbird have been recorded at Paruku, 21 of which were breeding. Paruku Rangers captured two images of the endangered night parrot on camera traps set in the GSD in 2017 and 2018.
Threatened species
The GSD supports one threatened plant species and 30 threatened animal species, including:
- Warrana/great desert skink (Liophilis kintorei)
- Princess parrot (Polytelis alexandrae)
- Night parrot (Pezoporus occidentalis)
- Greater bilby (Macrotis lagotis)
- Kakarratul/northern marsupial mole (Notoryctes caurinus)
- Sandhill dunnart (Sminthopsis psammophila; NT section of GSD)
- Northern quoll (Dasyurus hallucatus)
- Australian bustard (Aredeotis australis)
- Brush-tailed mulgara (D. blythii)
- Grey falcon (Falco hypoleucos; near threatened)
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.
Invasive species particularly 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.
Parkinsonia (Parkinsonia aculeata) has been recorded in the GSD. It can form dense, impenetrable thickets around watercourses.
Visiting the Great Sandy Desert
The northern sections of the Canning Stock Route run through the Great Sandy Desert. For more information see Halls Creek Tourism