Eastern barred bandicoot (Perameles gunnii)
|French:||Péramèle À Long Nez De L´est|
|Size||Head-body length: 27 – 35 cm (2)|
Tail length: 7 – 11 cm (2)
|Weight||0.5 – 1.5 kg (2)|
Classified as Near Threatened (NT) on the IUCN Red List (1).
The eastern barred bandicoot is a small marsupial with large, pointed ears, a long, tapering snout, pink nose and whiskered muzzle (3) (4). The soft, sandy greyish-brown fur is patterned with three to four distinctive diagonal pale bars on the hindquarters, giving the species its common name and distinguishing it from the brown bandicoot (Isoodon obesulus), which lacks such stripes (3) (5). The belly, feet and short, thin tail are pale grey to creamy white (3).
There are two very distinct populations of the eastern barred bandicoot, often considered to be subspecies: the mainland subspecies and the Tasmanian subspecies. The mainland subspecies was formerly distributed across south-eastern South Australia and Victoria, but is now thought extinct in South Australia, as it has not been seen there for over 100 years (6) (7), and is extremely rare in Victoria, largely restricted to the basalt plains extending from near the South Australian border to the Melbourne area (1) (7). The other subspecies is found only in Tasmania (1).
Original native habitat is grassland and grassy woodland, usually on flat or gently rolling plains (1), particularly along watercourses (7). In more recent years, the eastern barred bandicoot has adapted to living in highly modified habitats such as tree plantations, farmland, gardens, parklands, rubbish tips, cemeteries and under out-buildings. These areas are often dominated by introduced weed species, providing areas of dense cover close to suitable feeding habitat (1) (7).
This solitary, nocturnal species shelters by day in a simple ground nest of grasses, leaves and twigs, generally under some form of vegetation cover, and emerges at dusk to forage for food (2) (5). Abandoned rabbit burrows are also sometimes used as daytime refuges (5). This omnivorous opportunist feeds at night on a wide range of invertebrates and plants, most of which are found in the soil or leaf-litter (1) (2). The animal’s strong claws and long slender snout are used to dig small conical holes in the ground, from which its quarry is extracted (4). Food items include grubs, earthworms, beetles, grasshoppers, adult weevils, insect larvae and slugs, as well as roots, berries, grasses, mosses and seeds (4) (5).
Individuals come together to breed, but only one adult bandicoot occupies a nest (4). Young are born from June to February in Tasmania and at any time of the year on mainland Australia (5). A female may produce as many as three to four litters during a year in favourable conditions, each litter typically containing one to four young. The reproductive rate is high, but so too is the juvenile mortality rate. Young remain in the mother’s pouch for around 55 days and in the nest for a week or two after that (4). Both sexes begin to breed at four months of age (1).
Mainland populations of eastern barred bandicoots have been devastated as a result of habitat loss, with almost 99 percent of the original habitat destroyed or modified, and through predation by introduced species. Although the species suffers from predation by native snakes, raptors, carnivorous marsupials and, formerly, by dingoes and aboriginal humans, this is now far outweighed by predation by, and competition with, introduced species. The most devastating predators are the introduced red fox (Vulpes vulpes) and domestic cat (Felis catus) and dog (Canis familiaris). The introduced European rabbit (Oryctolagus cuniculus) also impacts the eastern barred bandicoot by reducing habitat through excessive grazing, possibly excluding bandicoots from favoured shelter areas, and perhaps competing for food. Toxoplasmosis has been reported in the eastern barred bandicoot in both Tasmania and Victoria, with cats thought to be the probable carrier of the infection. Poisoning by pesticides, collisions with motor vehicles, fires and accidental trappings in rabbit snares are other significant causes of mortality (1).
Mainland bandicoots, which have declined far more dramatically than on Tasmania, have been brought back from the brink of extinction by an intensive captive breeding and re-introduction programme (3). Captive breeding was first carried out at the Serendip Wildlife Research Station in 1972, although primarily for research purposes rather than breeding for reintroductions (7). At the same time, local conservation actions were initiated at Hamilton, the focus of the remaining population (1). The Serendip captive colony closed down by 1979 but, in 1988, another captive colony was established in large pens at Woodlands Historic Park, and an intensive captive breeding programme was carried out to produce offspring for release into the nature reserve. In 1992, the Zoological Parks and Gardens Board of Victoria assumed responsibility for captive breeding (7). Captive-bred individuals from here have since been released at seven reintroduction sites (7), including two protected by fox proof fences at Hamilton Community Parklands and Woodlands Historic Park, three released into the wild at ‘Mooramong’ near Skipton, Lake Goldsmith Wildlife Reserve near Beaufort and Floating Islands Nature Reserve near Colac, and one on a private property ‘Lanark’ at Branxholme (8). As a result of these efforts, there is now a total population of around 2000 individuals (3). Despite concentrated predator control efforts at Floating Islands and Lake Goldsmith, the populations at these sites have struggled and are now considered lost completely from Floating Islands (8). A studbook has also been established to manage the genetic stability of the captive population (7).
Although the population in Tasmania is still relatively secure, evidence of declines prompted the federal government to fund a recovery programme, and management now focuses on habitat improvement and control of feral and domestic cats. Fortunately, Tasmania has no red foxes, and native carnivorous marsupials do not pose a significant threat (1).
To learn more about conservation of the eastern barred bandicoot see:
Authenticated (27/11/2007) by Professor John Rodger, University of Newcastle, Australia.
- Invertebrates: animals without a backbone.
- Larvae: stage in an animal’s lifecycle after it hatches from the egg. Larvae are typically very different in appearance to adults; they are able to feed and move around but usually are unable to reproduce.
- Marsupial: a diverse group of mammals characterised by their reproduction and development. The embryo is born 11-35 days after conception. The tiny embryo-like neonate crawls up the mother’s belly and attaches to a teat, usually within the marsupium (pouch) where it stays until it is weaned, which can be a relatively long period of time. This long dependence on milk is the only source of nutrition and can last several months in large marsupials, such as kangaroos.
- Nocturnal: active at night.
- Omnivore: an organism that feeds on both plants and animals.
- Subspecies: a population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.
IUCN Red List (December, 2009)