The Disribution of Pseudomys shortridgei (Muridae : Rodentia ) and its Relevance to that of other Heathland Pseudomys

Abstract

Pseudomyine rodents today often show extremely restricted and disjunct distributions, yet evidence from subfossil deposits suggest these species were widely dispersed and abundant in Recent times. Previous explanations for this decline such as a widespread epidemic, climatic change, and competition with introduced rodents appear inadequate. A new survey technique was used to determine habitat preferences of small mammals in the Grampians region in western Victoria. The distribution of Pseudomys shovtvidgei was demonstrated to be principally confined to floristically rich treeless heath communities. This animal appeared to require the consistent presence within its habitat of a number of plant species, whose availability depends upon a specific fire regime. The habitat requirements of Pseudomys albocinereus and P. novaehollandiae are similar to those of P. shortridgei. Such close habitat association suggests that a change in vegetation may be catastrophic to the small mammal species. A relationship between the alteration and alienation of the Australian environment by European man, and the decline of the pseudomyines, is postulated.