Facts

Leadbeater’s Possum. Photo – J.P. Ferrero.

Leadbeater’s Possum was gazetted as the Victorian Mammal Emblem in 1971.

Listed Species

Leadbeater’s Possum is listed under the Victorian Flora and Fauna Guarantee Act 1988 as threatened.

Federally, Leadbeater’s Possum is listed under the Environment Protection & Biodiversity Conservation (EPBC) Act 1999 as endangered.

It is listed as Critically Endangered in The Action Plan for Australian Mammals (Woinarski et al., 2014, CSIRO).

The IUCN (International Union for the Conservation of Nature) Red List of Threatened Animals 1994 lists Leadbeater’s Possum as endangered.

Threats to Survival

Logging of the Mountain Ash forests in the Central Highlands for woodchips (paper production) has resulted in the loss of vast areas of Leadbeater’s Possum habitat.

The fragmentation of suitable habitat by timber harvesting causes isolated small populations of animals, which are then unable to interact with other colonies for breeding.

Stochastic events, such as bushfires, disease, drought (climate change) and collapsing old habitat trees are also threatening processes for Leadbeater’s Possum.

Juvenile Leadbeater’s Possum. Photo: David Lindenmayer.

History

• 1867 First specimens were collected at Bass River in Gippsland, Victoria. Called the Bass River Possum.
• 1909 LbP last collected from the wild – declared extinct in 1950’s
• 1961 (3rd April) Eric Wilkinson rediscovered LbP at Cambarville and Tommy’s Bend, near Marysville in the Central Highlands
• 1971 LbP declared the Victorian State Faunal Emblem, alongside the Helmeted Honeyeater
• 1973 LbP first bred in captivity by naturalist Des Hackett
• 2006 Death of the last Leadbeater’s Possum in captivity in Australia
• 2009 Black Saturday bushfires destroy around 45% of LbP habitat and population numbers in the wild are halved to an estimated 1200 (+ 25%) individuals.
• 2010 Kasia died peacefully in her sleep at just over 10 years of age at Metro Zoo, Toronto Canada. At the time she was the last captive Leadbeater’s Possum anywhere in the world.
• 2011 DSE and Parks Victoria ‘rescue’ the last 3 LbP’s from Lake Mountain (a population of around 300 having been destroyed in the 2009 fires) after a feral cat is filmed hunting near their nest box and a number of animals had ‘disappeared’. They are taken to Healesville Sanctuary. One animal later dies from unknown causes in its enclosure.
• 2012 Healesville Sanctuary begins a new Captive Breeding Program for lowland Leadbeater’s Possums from Yellingbo Nature Conservation Reserve (NCR). The programs “founders”, new wild possums, have been brought into captivity to establish a breeding population. The breeding program is based only on the genetically distinct Yellingbo population of Leadbeater’s Possums. (2015 no breeding has been reported at this time)
• 2013 (July) Two Lake Mountain LbP’s are put on display in the Nocturnal House at Healesville Sanctuary after DEPI refuses to issue a permit to return them to their wild habitat.
• August 2013 Professor David Lindenmayer calls on the Victorian Government to expand the current LbP Reserve System to include all LbP remaining habitat in the Central Highlands (including areas currently available for clearfell logging) in a new Great Forest National Park.

Lake Mountain Leadbeater’s Possum habitat burnt in the 2009 bushfires. Photo: Pam Miskin.

Post Bushfire February 2009

Following the February 2009 bushfires in the Central Highlands, Leadbeater’s Possum is in serious decline. Over 45% of their best territory was destroyed by the intense fires and estimates put the numbers of animals at around 1,200 animals but there could be less than 1,000 remaining.

There are approximately 40 Leadbeater’s Possums living in the Yellingbo State Nature Conservation Reserve alongside with the other Victorian Faunal Emblem, the Helmeted Honeyeater.

Leadbeater’s Possum in captivity / zoos

From the original captive Leadbeater’s Possum breeding program (pioneered by Des Hackett) the last captive possum in Australia died in the Healesville Sanctuary in 2006.

Kasia in Toronto Zoo. Photo: Brent Huffman.

“Kasia” was a 10 year old female Leadbeater’s Possum living at Toronto Zoo. She died in 2010. Descending from Hackett’s original captive bred possums she was the last Leadbeater’s Possum in captivity anywhere in the world. Her parents were born at Healesville Sanctuary in Victoria and were sent to Canada to enhance the captive breeding program. The successful captive breeding program was not continued as there was no structured release program for any of the captive bred animals.

In her last years Kasia was not on display at the zoo but was held in an off display enclosure by herself.

In 2012 a new captive breeding program was begun at Healesville Sanctuary. The program began by sourcing (bringing into captivity) animals from the wild population at Yellingbo. Although the same species, the Yellingbo animals are genetically distinct from the Central Highlands population. As of early 2015 the captive animals have not bred, consequently there is no plan in place for release of any captive bred animals back to Yellingbo, although other areas in the region are being investigated as possible future release sites.  There is no captive breeding program planned for the Leadbeater’s Possums found in the Central Highlands forests – habitat protection by ending logging of Mountain Ash forests in their range is their best hope for survival.

Taxonomy

Common name: Leadbeater’s Possum (at first, Bass River Possum)
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Diprotodontia
Family: Petauridae
Genus: Gymnobelideus
Species: leadbeateri

Gymnobelideus: from Greek: gymno – naked; belideus – dart, arrow; the Sugar Glider was then known as Belideus (dart) because of its flight, Leadbeater’s Possum was naked in that it lacked the glider’s gliding membrane.

leadbeateri: in honour of John Leadbeater (1831-88), a taxidermist, who preserved the first LbP specimens at the Museum of Victoria.

Kasia. Photo: Brent Huffman.

Leadbeater’s Possum features, appearance and diet

Leadbeater’s Possum is a nocturnal, small arboreal (tree dwelling), omnivorous (eats animals and plants) marsupial (mammal which gives birth to tiny underdeveloped joeys, which usually grow in the mother’s pouch).

Body length: 150 – 170 mm
Tail length: 145 – 165 mm
Weight: 100 – 165 g

Colour: Grey to greyish-brown above and paler below. Has a dark mid-dorsal (along centre of back) stripe.
Appearance: Similar to a Sugar Glider, but without a patagium (gliding membrane) and has a long club-shaped tail.
Diet: Exudates (saps and gums) from wattle and eucalypt manna (sweet secretion of leaves & branches); honeydew (droplets of sugary liquid produced when insects pierce leaves) secretions; and a variety of arthropods (invertebrates with jointed legs) crickets, beetles, flies, moths, ants and spiders.

Leadbeater’s Possum a nocturnal animal climbing down tree at night.

 Life history

Leadbeater’s Possum use shredded bark for their nests. Photo: Shire of Yarra Ranges.

• Leadbeater’s possums live in colonies – up to 12 animals
• Only one pair per colony will breed
• Matriarchal society (female dominated)
• Territory is 1.5 – 3 hectares and is well defended
• Breeding can occur twice a year (spring/summer & autumn/winter)
  Up to 2 joeys in a litter
• Females can breed again in the same season if the first litter dies
• Life span in the wild is only about 5 years, but up to 13.5 in captivity

Important forest habitat features for Leadbeater’s Possums

• Number of big, old, hollow-bearing trees available for nesting
• Density and type of wattle trees in the surrounding understorey
• Smooth barked gum trees with hanging bark ribbons
• Number of shrubs in the surrounding understorey
• Slope of the site
• Connectivity, allowing animals to move around their territory

Structure of Leadbeater’s habitat in Mountain Ash forests

Some of the major plants of the regrowth Central Highlands forests inhabited by Leadbeater’s Possum:

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Important habitat feature: old stags.

Stags are the very large, dead or dying trees usually over 200 years old in Mountain Ash forests. Leadbeater’s Possums nest in the large hollow trunks of these trees.

Old stag tree amongst Silver Wattle & Mountain Ash at Cambarville. Photo: Pam Miskin.