The western barred bandicoot (Perameles bougainville), also called the Shark Bay bandicoot or the marl, is a small type of bandicoot that once lived in dry and somewhat dry areas of southern Australia. It is no longer found in most of the places it used to live and became limited to Bernier and Dorre islands in the early 1900s. Since the start of the 21st century, programs to reintroduce the species have been successful. As of 2025, the western barred bandicoot lives on four islands in Shark Bay and six protected areas on the mainland: one in Western Australia, two in South Australia, and three in New South Wales.

Description

The Western barred bandicoot is smaller than the eastern barred bandicoot (Perameles gunnii) and has darker fur, which is a grizzled brown. It is about 1.5 feet (46 cm) long. The animal has two "bars" across its rump and a short, tapered tail. It was a solitary hunter that was active during early morning and late evening. It ate insects, spiders, worms, and sometimes tubers and roots. When threatened, it usually jumps into the air and then digs into the ground to hide.

Taxonomy

The first recorded description of the Western barred bandicoot came from a specimen collected at Peron Peninsula in 1817 by naturalists on the Uranie. Different populations of the Perameles species have been given various names based on their location in Australia:

• P. myosurus myosurus – King George Sound, Western Australia
• P. fasciata – Liverpool Plains, New South Wales
• P. myosuros notina – St Vincent Gulf, South Australia
• P. bougainville – Shark Bay, Western Australia

Because all mainland species are now extinct, early scientists likely described the same species using differences in fur color from local populations. However, this remains unclear due to the lack of mainland specimens. In 2000, the Environmental Protection and Biodiversity Conservation Act 1999 identified two distinct groups: P. bougainville fasciata was declared extinct, and P. bougainville bougainville was classified as endangered. Today, all are recognized as a single species, Perameles bougainville.

Ecology

The distribution history shows that the species lived in many different types of vegetation, depending on where they were located in mainland Australia. These habitats included areas with Allocasuarina seedlings, open salt bush plains, blue bush plains, stony ridges next to scrubland, and along the Murray-Darling river system. Today, the last natural habitats for the species are in vegetated beach dune scrub, low heath, and hummock grasslands.

The breeding season begins with the first heavy rainfall after the summer drought in autumn. Female Western barred bandicoots reach sexual maturity at 3 to 5 months old and weigh an average of 244 grams (8.6 oz). A female carries 1 to 3 young in her pouch, usually 2 young, with larger mothers having more offspring. Four young have been recorded in pouches in South Australia. The female carries her young from March to November. Male Western barred bandicoots reach maturity at 4 to 6 months old and weigh an average of 195 grams (6.9 oz). Female Western barred bandicoots are larger than males, making them the only bandicoot species where females are bigger than males.

The Western barred bandicoot is a solitary animal that eats both plants and animals. It searches for food alone, consuming plant matter, invertebrates, and small lizards. The animal builds a hidden nest from materials found in its habitat and often uses the same nest every night. Only females share their nests, and they do so only with their young.

Distribution

Before European settlers arrived, the Western barred bandicoot lived widely across southern mainland Australia, from Western Australia to central New South Wales, Victoria, and South Australia in dry and not-so-dry areas. The last known sighting of the species on the mainland was in Ooldea, South Australia, in 1922, and in Rawlinna, Western Australia, in 1929. The species was considered extinct on the Australian mainland, Dirk Hartog Island, and Faure Island before reintroduction efforts began. Today, the only natural populations of the species survive on Bernier and Dorre Islands in Shark Bay, Western Australia.

A program to help threatened marsupials brought the Western barred bandicoot back to mainland Australia in 1995 to Heirisson Prong, Shark Bay, 66 years after its last known sighting on the mainland. This effort did not succeed, and the species is now locally extinct in that area.

However, the species was successfully reintroduced to the enclosed Arid Recovery Reserve at Roxby Downs, South Australia, in 2000, and to Faure Island, Shark Bay, in 2005. It was also reintroduced to a large enclosed reserve at Mount Gibson Sanctuary in Western Australia in 2017, to Dirk Hartog Island in October 2019, to a protected area within Sturt National Park in 2021, and to a fenced private reserve on South Australia’s Eyre Peninsula in August 2021.

In September 2023, the species was released into two large enclosed reserves in New South Wales: the Pilliga Forest and Mallee Cliffs.

Captive breeding programs on the mainland at Dryandra Woodland in Western Australia were not successful. However, captive populations are maintained at the Barna Mia Nocturnal Animal Sanctuary, where visitors can see the animals in a controlled environment within the Dryandra Woodland.

Disease

In 1999, the Western barred bandicoot was found to have skin problems called papillomatosis and carcinomatosis syndrome. This condition is similar to warts and was first seen in animals kept in captivity in 1999. Wild populations were first observed with the disease in 2001. The illness is considered a new disease and is different from any skin conditions previously recorded in Australian marsupials. It only affects adult Western barred bandicoots, with symptoms usually appearing at about 3 years and 2 months old. Lesions grow larger over time and can become serious. Infected animals typically live to be about 4 years and 6 months old, with most surviving about 1 year and 4.5 months after becoming sick, either by natural causes or euthanasia. Today, the disease is only found on Bernier Island and in captive populations from Bernier Island. Until recently, the disease limited the movement of the species to animals from Dorre Island. However, in 2019, animals from Bernier Island were moved to Dirk Hartog Island after being visually checked for signs of the disease.

Predators

There are records showing that the native Gould's monitor (Varanus gouldii) and the western quoll (Dasyurus geoffroii) hunt other animals.

Since European settlers arrived in Australia, predation by non-native species and human activities are considered the main reasons for the loss of many species. These effects mainly harm small and medium-sized rodents and marsupials that weigh between 35 and 5,500 grams. Up to 49% of the original species in New South Wales have been impacted, including the extinction of the Western barred bandicoot on the mainland. Feral cats are believed to have caused the disappearance of many native mammals before 1857. Foxes have become common in the area and are also linked to the decline and extinction of several Australian mammal species.

Introduced rabbits are not predators, but they compete with the Western barred bandicoot for food and habitat. Rabbits also change the plants that the bandicoots rely on for survival. When rabbit numbers decrease, the number of babies born to Western barred bandicoots increases.

In 1990, a fence was built across a narrow part of Heirisson Prong to keep out foxes and feral cats. The goal was to protect a 1,200-hectare area at the tip of the peninsula from non-native predators. The original group of Western barred bandicoots on Dorre Island included 14 individuals. This area was closely watched and managed, offering a safe refuge of 17 hectares (42 acres). The number of bandicoots changed over time, with the highest count reaching 470 in 2006. These changes were connected to the arrival of foxes and cats inside the fenced area. Feral cats were mainly responsible for the extinction of Western barred bandicoots on Heirisson Prong in 2008.

Conservation

Conservation efforts for the Western barred bandicoot began in 1995, when 14 bandicoots from Dorre Island were brought back to Heirisson Prong. In 1990, a fence was built across a narrow part of Heirisson Prong to keep out foxes and feral cats. This allowed a 1,200-hectare area at the tip of the peninsula to be free of non-native predators.

Low genetic diversity can make endangered species more likely to face challenges in conservation efforts. Captive breeding programs can be more successful if scientists understand genetic information. Losses in genetic diversity caused by small population sizes on islands may reduce the species’ ability to survive, making them more likely to get sick, which is already happening.

The Western barred bandicoot lives in limited areas, and the species is very sensitive to human activities, climate change, disease, and predators. These conditions increase the risk of the species becoming critically endangered or extinct quickly.

• International – Vulnerable: The species was previously listed as rare (1982–1990) and endangered (1994–2008). On 16 March 2014, the IUCN changed its status to Vulnerable D2.
• National – Endangered: The species P.bougainville bougainville from Shark Bay is listed as endangered under the Australian Environment Protection and Biodiversity Conservation Act 1999 since 16 July 2000.
• National – Extinct: The species P.bougainville fasciata (eastern), Liverpool Plains Striped Bandicoot, is listed as extinct under the Australian Environment Protection and Biodiversity Conservation Act 1999 since 16 July 2000.
• Western Australia – Vulnerable: Listed as vulnerable under the Biodiversity Conservation Act 2016 (Wildlife Conservation (Specially Protected Fauna) Notice 2018, schedule 3).
• South Australia – Endangered: Listed as endangered under the National Parks and Wildlife Act 1972 since 1 July 2015 (Schedule 7).
• Victoria – Extinct: The Western Barred Bandicoot (eastern subspecies) Perameles bougainville fasciata is listed as extinct under the Flora and Fauna Guarantee Act 1988.
• New South Wales – Extinct: Perameles bougainville fasciata Gray, 1841 (Western Barred Bandicoot, mainland) is listed as extinct under the NSW Biodiversity Conservation Act 2016.