Wildlife in the arid and semi-arid areas of Australia has evolved to cope with little or no available surface water. Mammals such as bilbies, mulgaras and dunnarts as well as many insect-eating birds and reptiles can survive without drinking; they obtain all the water they need from the food they eat.
Since white settlement and the development of the pastoral industry, thousands of dams, bores, windmills and troughs as well as thousands of kilometres of bore drains have been built to provide water for sheep and cattle. As a result, millions of hectares once very distant from permanent surface water have become accessible to stock, feral grazers such as goats and rabbits, and predators such as cats and foxes. These vertebrate pests compete with native animals for habitat and food, or prey directly on them, and were previously only able to range into arid areas following rain.
Grazing in these formerly water remote areas has had impacts on native shrub and grassland species. Some species are sensitive to grazing and have been lost from large areas, while others have benefited and expanded their range. Scientists have called these two groups 'increasers' and 'decreasers'.
The 'increasers' are those species that have thrived in the new conditions. The 'decreasers' include plants that are sensitive to grazing and the animals that depend on them, and also animals that are vulnerable to the impacts of grazing and to predators. For example, kangaroos are now able to graze over much larger areas of Australia and their numbers have increased. By contrast, bilby numbers have declined dramatically, and they are now only found in a few areas remote from water in less than one percent of their former range. They and some other arid-zone animals are now listed and protected under the Environment Protection and Biodiversity Conservation Act 1999.
Across much of the Great Artesian Basin area, only tiny slivers of land more than six kilometres from water now remain. With water piping and the multiplication of water points, even these are disappearing. And some areas within the driest parts of Australia, such as the Simpson Desert, are only recently being developed and new water points provided. The Great Artesian Basin Sustainability Initiative program does not fund new watering points in these areas.
If our unique arid-land wildlife is to survive, it is vital that we protect and restore areas that remain free from the threats that accompany new water points.