Gibson Desert

• Category: Desert Biomes.
• Geographic Location: Australia.
• Summary: This largely untouched desert nevertheless faces the decline of many of its species and its biodiversity.

One of the largest deserts in Australia, the Gibson Desert covers some 60,000 square miles (155,400 square kilometers) of western Australia between the salt lakes of Disappointment and Macdonald, south of the Great Sandy Desert, east of the Little Sandy Desert, and north of the Great Victoria Desert. It was named for the explorer Alfred Gibson, who died there on an expedition in 1874. Broadly, the desert can be divided into the lateritic (aluminum- and iron-oxide-rich silica soil) plain, which takes up the bulk of the desert, and the dune field in the northeastern corner. The desert is characterized by red sand plains and dune fields, low rocky ridges, several small saline lakes, and large expanses of thin grass growing out of gravelly terrain. The upland is laterized on Jurassic and Cretaceous sandstone.

The desert's ecosystem is considered to be relatively stable, although a shift to more frequent and abundant rainfall has some climate change experts concerned. The flora and fauna of the Gibson Desert, like many in desert environments, are adapted to take maximum advantage of rainfall. If the rainfall levels increase, the range of many species may also increase, encroaching upon additional territories and destabilizing the biome.

There are few established paths through the desert, and the two main tracks—east-west to Alice Springs via Papunya, and north-south along the Gary Highway—are not always accessible. The land's principal use is for mineral exploration; most of it remains untouched. Little of the known mineral resources have been explored; there are no major mines in the region. A total of 10 percent of the desert is in conservation reserves, including the Gibson Desert Nature Reserve.

The Gibson's rainfall ranges from 8 to 10 inches (20 to 25 centimeters) a year, most of it in the summer, and the climate is generally hot. Summer maximums are around 104F (40C), while winter temperatures vary from 45 to 65F (7 to 18C). Summer rains help prevent summer wildfires from spreading, but are not always enough. Groundwater from the Officer Basin and Canning Basin feeds several springs. The quaternary alluvial is associated with paleodrainage features, supporting coolibah woodlands flora over bunch grasses.

The bulk of the human population in this area have been Indigenous Australians, including the Kiwirrkurra and Wanarn communities and the Pintupi group, who were believed to have been the last uncontacted tribe in Australia until their 1984 departure from the central-eastern Gibson Desert when the prevailing drought depleted its springs and food sources. The few sedentary population centers are scattered around the eastern margin of the desert, such as the towns of Mantamaru, Warakurna, and Warburton—the closest weather station for the region and the source of most climatic data.

Vegetation

Vegetation varies throughout the desert, according to the soil type and landscape features. The lateritic gibber plains of the desert are characterized by mulga parkland (spreads of the short mulga tree or Acacia aneura) over hard spinifex (Triodia basedowii) grasslands. Mulga trees resemble the eucalyptus tree and can live for over 200 years.

The red sand plains and dunes are home to soft spinifex (Triodia pungens), also called porcupine grass, on which may be found a mixed shrub steppe, including species of hakea, acacia, and grevillea. Spinifex roots burrow deeply into the soil and may be found as deep as 20 feet (6 meters) in the soil. The lateritic upland areas are home to mulga scrub in the south and scrub steppe in the north. The grasses have faced a moderate threat from the weed invasion of buffle grass.

Wildlife

No comprehensive biodiversity study has been done of the Gibson Desert. The desert has about forty-five animal species, six of which are exotic mammals introduced recently. Common species in the area include rabbits, foxes, wildcats, and camels. Foxes and cats are persistent threats to smaller mammal and bird species, and have contributed to the decline and near-extinction of several. Though there has been no widespread land degradation, what little occurs is the result of camels and rabbits feeding on vegetation. Several species have disappeared from the region, including the western quoll (Dasyurus geoffroii), numbat (Myrmecobius fasciatus), red-tailed phascogale (Phascogale calura), golden bandicoot (Isoodon auratus), and lesser bilby (Macrotis leucura).

The desert is also home to the red kangaroo, one of the world's largest marsupials, found in Australia's hottest and driest ecoregions. The kangaroo's mode of traveling by hopping evolved to protect its feet from the hot sand and is an energy-efficient use of its powerful muscles, allowing it to travel great distances between food sources—a necessity in the desert.

The bilby, a burrowing nocturnal mammal, survives by sleeping in dens (which are at least 10 degrees F or 6 degrees C cooler than the outside air in the summer) during the day to avoid both the hot sun and active predators. It drinks no water, relying on a highly efficient digestive system that provides water from a diet of fungus, insects, and vegetation.

A lizard (Moloch horridus) known as the moloch, thorny devil, or thorny dragon thrives in the Gibson Desert and is distantly related to the horned lizard of American deserts.

Rare species, some of which may be found in other ecoregions, include the marsupial mole, the rock wallaby, the malleefowl, the princess parrot, and the woma python. Birds are particularly rare in the Gibson Desert, and the princess parrot is the only limited-range bird that has been seen regularly, thanks to a population thereof at Tobin Lake. Emus, hooded robins, jacky winters, and Australian bustards are also found in small numbers. The grasslands are home to a large population of striated grass wrens (Amytornis striatus), while the few wetland areas along Cooper Creek provide waterbird habitats.

Conservation Efforts

In 2007, the faunal attrition index for the desert (a measure of loss of species richness) was high, at 0.45. The faunal contraction index, measuring the decline of range covered by a given species, was 0.44. Similar trends occurred throughout Australia and continued throughout the twenty-first century. Australia's land mammals have faced an exceptionally high extinction rate, with over 10 percent of its endemic species lost in the past 200 years. In 2015, 21 percent of Australia's endemic land mammals were threatened. By 2021, more than 1,900 species and ecological communities were at risk or threatened. Furthermore, the number of threatened species listed has risen for almost all taxonomic groups. In terms of flora, according to Australia's State of the Environment Report, "the oversight of 112 threatened plant species at more than 600 sites for more than twenty years shows, on average, a 72 percent decrease in Australian threatened plant populations." The biodiversity of the Gibson Desert is no exception, though fire burning practices and its lack of human development have protected the area somewhat. However, the processes putting most species at risk are increasing fragmentation in the dune fields, the predation of or competition with feral animals, invasive species, and grazing pressure.

The Gibson Desert's Gnamma Holes and Lake Gruszka are both considered to be wetlands of national significance. Lake Gruszka is considered to be in pristine condition, with no foreseeable degradation; Gnamma Holes requires minimum intervention for full recovery, as the site is no longer maintained by the indigenous people. In both cases, animals are the biggest risk to the ecosystem through predation, habitat building, or land degradation from feeding on plants.

The desert also has five seasonal freshwater/floodplain lakes in near-pristine condition, as well as a seasonal river. All are at mild risk from changes in the Gibson Desert's fire regime.

Bibliography

“Australia's Endangered Animals.” The Nature Conservancy Australia, Mar. 2021, www.natureaustralia.org.au/what-we-do/our-priorities/wildlife/wildlife-stories/australias-endangered-animals/. Accessed 29 Jan. 2025.

Beard, J. S. Plant Life of Western Australia. Kangaroo Press, 1990.

“Biodiversity: Australia State of the Environment 2021.” State of the Environment Report, Australian Government, 2021, soe.dcceew.gov.au/overview/environment/biodiversity. Accessed 29 Jan. 2025.

“Gibson Desert.” ecoxplore, 2025, ecoxplore.org/ecoregions/gibson-desert/. Accessed 29 Jan. 2025.

McInerney, Graham, and Alec Mathieson. Across the Gibson. Rigby, 1978.

Olson, David. “Gibson Desert.” One Earth, 23 Sept. 2020, www.oneearth.org/ecoregions/gibson-desert. Accessed 29 Jan. 2025.

Smith, Emily J.B., and Madison Snow. "Native Title Determination at Pila Nature Reserve in WA's Gibson Desert Sets New Precedent." ABC, 16 June 2022, www.abc.net.au/news/2022-06-16/native-title-determination-pila-reserve-gibson-desert-wa/101158082. Accessed 29 Jan. 2025.

Woinarski, John C., et al. "Ongoing Unraveling of a Continental Fauna: Decline and Extinction of Australian Mammals since European Settlement." Proceedings of the National Academy of Sciences, vol. 112, no. 15, 2015, pp. 4531-40. doi.org/10.1073/pnas.1417301112. Accessed 29 Jan. 2025.