Threatened species - Southern Brown Bandicoot

Introduction

The fauna and flora of Australia is characterised by high natural diversity (variety), unique species (not found elsewhere) and a high susceptibility to extinctions and declines(a). South Australia has a particularly poor record on species extinction with greater than 80% of the original native vegetation in agricultural regions cleared and 63 species, including 20 mammals, now extinct(b). Many species are clinging to survival in small, isolated areas that are vulnerable to outside influences. One such species is the Southern Brown Bandicoot (Isoodon obesulus).

Description

The Southern Brown Bandicoot marsupial has a long snout, small round ears, a short tail and large rump. The bandicoot is roughly a third to half the size of a rabbit (280-360 mm). They have brown fur with a golden speckled appearance and a pale white to cream coloured underside(c).

Status/Habitat/Distribution

The Southern Brown Bandicoot, once common and widespread from the southern Barossa Valley to Cape Jervis, is now restricted to isolated patches in Stringybark open forests and woodlands scattered throughout the wettest parts of central and southern Mount Lofty Ranges(d).

The conservation status of a species can be categorised from highest to lowest according to the following scale: extinct; endangered; vulnerable; rare; uncommon and common.

Due to its patchy distribution in South Australia the Southern Brown Bandicoot is considered to be vulnerable. Currently there are only three isolated groups located in the:

• Adelaide Hills (Belair National Park, Loftia Park and Scott Creek Conservation Park);
  
• Central Fleurieu Peninsula (Cox Scrub and Mt Magnificent); and
  
• Southern Fleurieu Peninsula (Deep Creek and Waitpinga).

A major grouping of bandicoot sites occurs in the Adelaide Hills, including Scott Creek Conservation Park, in part located within the City of Onkaparinga (see map below). Bandicoot corridors appear to exist through to Belair National Park and Loftia Recreation Park where there is anecdotal evidence of bandicoots. At Scott Creek Conservation Park the distribution of bandicoots is widespread along watercourses and usually associated with low, open Eucalyptus species forests or woodlands with dense to very dense understorey and usually blackberry (Rubus ulmifolus), bracken fern (Pteridium esculentum) or common ground pinkberry (Acrotriche fasiculiflora).

The bandicoot is known to use certain plant species for shelter and protection from predators (fox and cat) including introduced plants such as blackberry and Phlaris species (grass) along with native plants such as yacca (Xanthorrhoea species) and sedge (Gahnia species).

Surveys are continuing in Scott Creek to monitor numbers of bandicoots since fox baiting was introduced into the park by the National Parks and Wildlife Service. Survey results in 1999 are encouraging with 27 bandicoot captures, up from 9 in 1998. Surveys have also been undertaken in the Onkaparinga Gorge (near Hackham) however no evidence of bandicoots has been discovered.

Response to pressure

In an effort to protect the Southern Brown Bandicoot possible initiatives include:

• protection of existing and establishment of new vegetation corridors linking known and potential bandicoot sites;
  
• controlled fox baiting and feral animal eradication programs;
  
• careful land management practices (eg if blackberries are removed then replace with suitable local native food species); and
  
• appropriate land use controls to prevent loss and damage to bandicoot habitat.