Red Dunes and Braided Rivers
The Simpson Desert is located in the southeastern part of this ecoregion. Here, red, arid dunefields and sandplains are covered with sparse shrubland and hardy clumps of spinifex grass. Cane grass thrives on deep sands along the crests of dunes. Mild winter temperatures in the desert encourage a thriving tourist industry, which falls off in the very hot summer months. Rainfall is low here, averaging less than 7.8 inches (200 mm) per year. In the northeastern part of this region, rivers lined with coolibah eucalyptus trees snake their way through low hills covered with hardy mitchell grass. This area is called "channel country" after the large, braided rivers.
Several sights in the Simpson Desert are not to be missed! The spectacular Big Red is a sand dune of immense proportions, the largest one found in the Simpson Desert. The vast Lake Eyre collects all the runoff from surrounding areas because of its low altitude (52 feet [16 m] below sea level). The lake bed has filled several times during the past century when rains were sufficient. When it is empty, it forms a large, glaring-white salt pan. Colorful desert flowers such as Sturt’s desert peas, Cunningham bird flowers, and billy buttons all bloom at the same time each year, taking advantage of the brief rains.
Animals that live in the Simpson Desert have special adaptations that enable them to survive in this hot, arid environment. So, unless you visit the desert after a good rain, you won’t see the unique water-holding frog. This amphibian can spend up to several years in its burrow, waiting for heavy rains, when it emerges to breed in temporary pans and lakes. Sand-sliding skinks are no easier to spot. These nocturnal lizards that resemble snakes with small limbs will quickly burrow into the sand when disturbed. Telltale signs of their presence can be seen in the distinctive, wavy tracks they leave on the sand dunes. Mammals found in this region, such as the mulgara (a small, mouse-like marsupial) and the spinifex hopping mouse, tend to be small and excrete incredibly concentrated urine to conserve water. The spinifex hopping mouse can normally be seen at dusk, bounding across the spinifex-covered sand dunes. A lucky visitor may see the brown-and-white Eryean grasswren, a rare and elusive bird that lives only in clumps of cane grass.
Cause for Concern
This region is not suitable for agriculture or grazing, so it has been spared those threats. Feral and introduced animals, such as rabbits and camels, are a problem because they eat the native vegetation and upset the natural ecological balance. Tourist traffic is increasing, which could damage the sand dunes and vegetation.
For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.All text by World Wildlife Fund © 2001