Across the rangelands of Australia, the once widespread distribution of Pseudomys desertor is contracting along the southern extent of its range. This change is suspected of being caused by either introduced herbivores removing areas of dense understorey, or a natural consequence of relatively low habitat variability, providing insufficient resources to sustain populations. We propose that the dominant driver will become apparent by investigating the consistency of indicator species, or their traits, identified from within critical habitats. The association between P. desertor and broad habitats will be examined from 2500 sites surveyed during the Biological Surveys of South Australia, and an additional 13 sites surveyed within an outlying population in the southern Flinders Ranges. Broad habitats will be defined using a cluster analysis, and key floristic and edaphic variables identified using an indicator species analysis, in PC-ORD. The abundance of captures will be used to indicate the species’ relative preference for each community. We anticipate the results of these analyses to indicate the relative availability of critical habitat, and if abundant, areas where the management of total grazing pressure need to be carefully managed to prevent further declines in the range of the species.