Photo: Leadbeater's Possum at Healesville Sanctuary - Najade

This article featured in Wildlife Lands Issue 19

Leadbeater’s possums are the only mammals endemic to Victoria, living almost exclusively in the mountain ash forests of the Central Highlands. Once believed extinct, the species was rediscovered in Marysville by Eric Wilkinson in 1961 to the delight of natural science enthusiasts globally. However, Leadbeater’s possums are still a highly threatened species. Protected under the Victorian Flora and Fauna Guarantee Act 1988, its status was raised from endangered to critically endangered under federal environmental laws in 2015 largely due to dramatic declines in both population and habitat. Habitat loss is the leading threat to the species, mainly due to commercial logging and a natural susceptibility to bushfires. The cumulative impacts have contributed to sustained deterioration of habitat quality and a rapid decline in nest sites.

Nocturnal, arboreal and relatively inactive, Leadbeater’s possums are thought to spend about three quarters of their time in nests crafted from strips of bark in old growth forest hollows. They consume gums, saps and honeydew (a sugary secretion produced by aphids and insects) and derive protein from invertebrates like tree crickets hiding beneath the bark of mountain ash trees.

With a maximum body length of just 17cm, the possums are small, fast and tricky to spot. Their tails are formed club-like, widening slightly close to the tip, and measure around 17cm in length. Typically a greyish brown colour on top with lighter fur beneath, they have a striking black stripe down their back. Their typical life span is five years, with maturity at two to three years. Fully grown, a possum weighs 100g–170g (roughly the same as an orange).

The timber industry is at loggerheads with those dedicated to the recovery of this species. Earlier this year, Federal Agriculture Minister Barnaby Joyce promoted a black-and-white approach, tweeting to put ‘people before possums’ and downgrade the species’ critically endangered status for the sake of Victorian logging jobs. Citizen scientists from both sides are conducting independent counts as they continue to debate the species’ abundance in proximity to native forest logging coupes.

In a recent opinion piece, Professor David Lindenmeyer suggested environmental protection and economic development needn’t be mutually exclusive, arguing for the restructuring of the logging industry to benefit both the possum and the Victorian economy. In his view, when you add the environmental assets of the state’s wet forests to the economic equation, a more sustainable management model would better advance both camps.

The National Recovery Plan for Leadbeater’s possum, finalised in February 2016, holds the species as an ‘indicator’ or ‘flagship’ species, meaning the threats they face are expected to affect many other less iconic species. If antiquated logging practices continue and the possum and other hollow-dependent animals are driven to extinction, the ecosystem function will be disrupted and this will, in turn, negatively impact the logging industry.

Though unverified, the population is estimated at little more than 1,500. However, the threat to their habitat posed by unsustainable logging and a naturally high susceptibility to bush fires (2009’s Black Saturday fires are held to have halved their number) is undeniable. More needs to be done to save this iconic species and private land conservation is central to success.