SAC 3: OUTCOME 2: CASE STUDY OF A THREATENED SPECIES – EASTERN BARRED BANDICOOT (PERAMELES

GUNNII)

Indi Campbell

Introduction

The Eastern Barred Bandicoot (Perameles Gunnii) is a small, rabbit sized marsupial native to Tasmania and Victoria, South-eastern Australia. It usually grows up to 35 centimetres long and weighs less than one kilogram. It is a yellowish-brown colour usually with 3-4 pale white bars on its hindquarters with large pointed ears and a tail which grows to 11 centimetres long.

Habitat

On mainland Australia the original native habitat was primarily native perennial tussock grasslands with scattered open woodlands and shrub cover, particularly along waterways. In recent years, the Eastern Barred Bandicoot has survived in highly modified habitats such as tree plantations, farmland, gardens and parklands.

Life history and ecology

The species is short-lived and generally only survives 2-3 years in the wild, but it can be highly fertile. Gestation lasts 12-13 days, and litters comprise of 1-5 young. Young bandicoots remain in the pouch for approximately 55 days, becoming independent and dispersing about three months after birth.

Eastern Barred Bandicoots occupy partly overlapping home ranges, with males occupying significantly larger areas than females. Densities vary markedly within and between sites, and between years. Recorded densities in Victoria range from 0.45 to 5.25 animals per hectare. The Eastern Barred Bandicoot is considered to be primarily insectivorous.

Behaviour

Eastern Barred Bandicoots spend their day resting in their nests. These nests are usually no more than a shallow slump in the ground with a dome of grass pulled over the top.

Usually only one Bandicoot occupies the nest, although young may share the nest with their mother for a week after they first leave the pouch.

After dusk, they immediately emerge and begin foraging for food. Bandicoots are solitary animals and only mix with other animals when breeding.

Life cycle

The Eastern Barred Bandicoot has a life span of up to six years, but generally survives between one to two years in the wild.

The sub-species is generally solitary, polygamous and nocturnal.

The bandicoot uses a nest for daytime refuge as well as breeding.

The bandicoots nests are constructed at, or just below ground level, often under a covering object.

Breeding

The young are born between late May and December. During a single breeding season a female may produce 3-4

litters with a litter size of 1-4 young. A female Bandicoot can potentially give birth to as many as 16 young in one year.

After a Bandicoot has fertilised its egg it is just a short 12 days before the young Bandicoot is born and is roughly the size of a jellybean.

At just nine weeks old after being in the mothers pouch feeding on her milk, the young Bandicoot leaves the nest and becomes independent.

Diet

Eastern Barred Bandicoots are omnivores Eastern Barred Bandicoots mainly eat invertebrates from the

soil. They locate their food using their well developed sense of smell. They then use their strong claws and pointed nose to dig small tapered holes from which they extract their food.

Root-eating grubs such as cockchafers and corbies are some of the foods the Bandicoots enjoy eating along with also feeding on beetles, earthworms, berries and fungi.

Bandicoots do not need to

drink as they obtain sufficient

water from the foods they

consume.

Threats

Introduced predators – Red foxes are considered to be the primary cause of extinction of a

number of Australian mammals, including the Eastern Barred Bandicoot. Control of predators is considered a key requirement for the successful reintroduction of Eastern Barred Bandicoots. Foxes were present at all five reintroduction sites where populations have now became extinct. If fox control is continuous and intensive, Eastern Barred Bandicoot populations can persist in the presence of foxes.

Cats and dogs will also prey upon Eastern Barred Bandicoots, particularly the young, but their impact on populations is less severe than that of foxes. A study showed that of 160 adult deaths have been attributed to the cat, and 3 to the dog.

Threats – continued

Habitat loss or modification – Over 99% of Victoria’s native grasslands and grassy

woodlands, in which the Eastern Barred Bandicoot formerly occurred, have disappeared. Extensive habitat alteration and destruction has occurred through the clearing of woodlands, establishment of exotic pasture grasses, grazing by domestic stock, altered fire regimes, addition of fertilisers, the introduction of rabbits and drought.

Small population size – It is now identified as a threat that inbreeding effects and

very low heterozygosity measures have been identified within the mainland Eastern Barred Bandicoot population.

Conservation status

The Eastern Barred Bandicoot is listed as threatened under the Flora and Fauna Guarantee Act 1988. It is considered critically endangered in Victoria according to DSE’s Advisory List of Threatened Vertebrate Fauna in Victoria.

Formerly widespread throughout Western Victoria, the population of the Bandicoots in Victoria is estimated to be as low as 150 animals. Since European settlement, however, the species has undergone a widespread, sustained and catastrophic decline in range and abundance. Reintroductions have been attempted at multiple locations within the species former range in south-western Victoria, and several small reintroduced populations are currently extant. The Eastern Barred Bandicoot’s range within Victoria is encompassed by the Victorian Volcanic Plains IBRA bioregion.

Captive breeding

A captive breeding colony of mainland Eastern Barred Bandicoots was established in pens at Woodlands Historic Park in 1988, to be used as a source for releases into the nature reserve. Although reproduction did occur, recruitment was lower than expected. In 1992, Zoos Victoria assumed responsibility for captive breeding and switched to intensively managed facilities to breed bandicoots for re-introductions. Bandicoots have since been bred for the recovery program at all three Zoos Victoria properties and at other facilities within Victoria and interstate.

Re-introductions

Eastern Barred Bandicoots were first introduced into extensive fence enclosures, resulting in the establishment of two confined populations. As part of the management plan for the species, one population was established in the 300 hectare reserve within Woodlands Historic Park in 1989. The second population was established at Hamilton in a 100 hectare enclosure within the Hamilton Community Parklands in 1990.

Recovery efforts

The last confirmed sighting of an Eastern Barred Bandicoot in the wild was in 2002 at Hamilton in south-western Victoria. Attempts have been made to establish reintroduced populations at eight sites within the species former range, of which three currently have extant populations.

Hamilton Community Parklands – The Hamilton Community Parklands on the northern perimeter of Hamilton contains an area of 100 hectares of plains grassy woodland enclosed by a 1.8 meter high electrified predator control fence. More than 120 bandicoots were released into the reserve between 1991 and 2003. the population reached a maximum recorded size of about 90 animals during 1993, but declined markedly and was presumed extinct by 2005. the fence design was ineffective at excluding foxes, and in 2005 was upgraded to include a floppy top. Once the reserve was determined to fox-free in 2007, another 30 bandicoots were released. Evidence of breeding was noted just three weeks after the release. The population is increasing and now occupies the entire reserve. No foxes have gained access to the reserve since the release, and fence maintenance is regular and ongoing. The current population size is thought to be 50-80 bandicoots.

References

http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=66641

http://www.parks.tas.gov.au/indeX.aspX?base=4830 http://en.wikipedia.org/wiki/Eastern_barred_bandicoot https://www.google.com.au/search?q=eastern+barred+bandico

ot&newwindow=1&safe=active&source=lnms&tbm=isch&sa=X&ei=9Dt7U-abHcrukgXam4DoCA&ved=0CAgQ_AUoAQ#imgdii=_

http://fame.org.au/news_resources/endangered_species/eastern-barred-bandicoot

http://parkweb.vic.gov.au/get-involved/volunteer/eastern-barred-bandicoots-volunteer-program

http://bird.net.au/bird/index.php?title=Eastern_Barred_Bandicoot http://www.dse.vic.gov.au/__data/assets/pdf_file/0012/103143/0

04__Eastern_Barred_Bandicoot_2009.pdf