Boundaries

This ecoregion encompasses the Great Sandy, Gibson, Tanami, and Great Victoria deserts.  It extends south to the coast along the Southern Ocean.

Topography

There is a large plateau in the middle of the ecoregion (500-600 m elevation).  The elevation drops with proximity to coasts on either side.

Freshwater habitats

This vast ecoregion covers 2,363,000 square kilometers, or 30% of Australia.  It consists of isolated, saline lakes and creeks that are mostly dry, except for during brief periods of sporadic rainfall.  Little permanent water has been found, and the region\'s fish exploration is severely lacking.

Terrestrial habitats

There is sparse vegetation in the deserts of this ecoregion.  In the Great Sandy Desert, high, red sand dunes extend in parallel rows for hundreds of miles. The region consists of desert sandridges and sandplains with tree steppe, shrubs, and open hummock grassland (World Wildlife Fund 2001a).

Ecological phenomena

Salt lakes that intermittently fill with water support nationally and internationally significant breeding habitat for waterbirds, although many of these lakes have not been assessed (Duguid et al. 2005).

Justification for delineation

This ecoregion is composed of six paleodrainage catchments (here referred to as the Palaeo-Victoria, Palaeo-Sturt, Palaeo-Internal, Palaeo-Oakover, Palaeo-south-western, and the Palaeo-southern), which were formerly connected to neighbouring drainages but have been isolated for quite some time (Van de Graaf et al. 1997;Unmack 2001).

Level of taxonomic exploration

Taxonomic exploration is good in the few areas that have actually been surveyed. Given that few areas have been surveyed outside of the Northern Territory, it is particularly difficult to assess (Duguid et al. 2005).