The distribution of the southern brown bandicoot (Isoodon obesulus obesulus) in South Australia

Abstract

This paper describes the South Australian distribution of the southern brown bandicoot (Isoodon obesulus obesulus) on the basis of records of its past occurrence and field surveys undertaken to determine its present distribution. Since European settlement I. o. obesulus has been recorded from four separate regions of the state: the Mount Lofty Ranges, the South East, Kangaroo Island and Eyre Peninsula. Subfossil remains show that I. o. obesulus also once occurred on Yorke Peninsula but there is no evidence that it has existed there in modem times. Field surveys conducted between 1986 and 1993 confirmed that I. o. obesulus still exists in the Mount Lofty Ranges, the South East and on Kangaroo Island. Its status on Eyre Peninsula is uncertain. Isoodon o. obesulus is vulnerable in the South East and Mount Lofty Ranges because of habitat fragmentation and predation by feral carnivores. The Kangaroo Island population is less threatened as large areas of habitat have been preserved and the fox (Vulpes vulpes) has not been introduced. The area of potential bandicoot habitat remaining in these three regions totals approximately 190 000 ha, most of which is already managed for nature conservation. This habitat is highly fragmented, occurring as small remnant patches of native vegetation separated by extensive tracts of cleared and modified land cover. The implications of this habitat configuration for the long-term survival of I. o. obesulus are discussed.