This week’s awarding of ‘endangered’ status to the large glider may come as a surprise to many Australians, but to experts it’s hardly unexpected.
On Tuesday, Australia’s Environment Minister Tanya Plibersek accepted advice from the government’s science committee on endangered species to “upgrade” the conservation status of the great southern and central glider (Flying petauroidslisten)), a large marsupial that inhabits the forests of the east coast of Australia.
It is the largest of the eastern Australian soaring possums (at least eight others are found here), known for its hairy body, plush ears and a canopy-like membrane that allows it to glide in the airs. Individuals typically reside in “dens” provided by old eucalyptus hollows. Some eucalypts provide the leaves which are their main source of food.
But the destruction of vital habitat during the catastrophic Black Summer bushfires of 2019-2020 pushed the species’ glider populations to the brink.
Extended family: large gliders are separate species and are probably all threatened
The great glider was first listed as vulnerable in 2016 and was considered a species – P flying. But since 2020, experts consider the glider to be at least three distinct species.
P.volans inhabits forests from Proserpine in the Whitsunday region of Queensland on the east coast of the mainland to woodland areas surrounding Melbourne, Victoria. P minor occupies the wet-dry tropical region near Townsville and Cairns in northeastern Australia, and has now been added to the endangered species list as ‘Vulnerable’.
A third species – P. armillatus – is considered vulnerable by the Queensland government and likely faces the same pressures as others.
“Glider taxonomy is not yet fully resolved,” says Professor David Lindenmayer of the Australian National University in Canberra. “There may be as many as five species of large gliders, and none of them are likely to be secure in number.
“We’re going to have to work hard to make sure we can conserve all of these species, as they are all an important part of Australia’s natural heritage.”
There is encouraging language from the Australian government, with Environment Minister Plibersek publicly backing efforts to help gliders recover from the Black Summer bushfires. But while these fires have had a devastating effect on many plant and animal populations, other factors such as climate change, habitat clearance and fragmentation, and timber harvesting pose existential threats to the survival of gliders.
“All of these various threats and factors interacting in different ways ultimately increase the risk of extinction,” says Luke Emerson, a researcher at Deakin University’s Center for Integrative Ecology who specializes in the ecology of arboreal marsupials like the glider.
“Rising temperatures, increased fire severity, shorter fire intervals, logging on top of that, habitat conversion and fragmentation…all of these things interact to exert greater pressure on arboreal marsupials.
“These multiple threats are interacting in ways that we can predict, but there are likely ways that we can’t predict that will also affect them negatively.”
The Bad List: More Australian icons added or reclassified in 2022
The great glider isn’t the only one to be listed on the National Register of Threatened Species in 2022.
Populations of the iconic koala (Phascolarctos cinereus) living in Queensland, New South Wales and the Australian Capital Territory were notably moved from vulnerable to endangered status earlier this year. The yellow-bellied glider (Petaurus australis australis) and long-nosed potoroo (Potorous Tridactylus trisulcatus) were listed as vulnerable in March.
And many non-mammalian species were added to the list in 2022.
by Watson (Litoria watsoni) and Littlejohn’s tree frog (L. littlejohni), gang-gang cockatoo (Callocephalon fimbriatum) and the southern Australian bass thrush (Zoothera lunulata halmaturina) have been added or put on the endangered species list, while the pilotbird (Pycnoptilus floccosus) has been added as vulnerable.
The work of protecting animal species from spiraling extinction is a difficult undertaking at the best of times. Triumphs are rare.
Of note is Zoos Victoria’s 33-year-old captive breeding program for eastern barred bandicoots (Perameles gunnii), which was removed in 2021 when the species – previously extinct in the wild – was downgraded to endangered. The species is now regenerating in specially fenced, predator-free release sites across Victoria.
For Zoos Victoria reproductive biologist Dr Marissa Parrot, the success of the bandicoot program was a career highlight. But alongside these all-too-rare moments of success, there are declines in other species.
“It’s such an amazing feeling to know that you’ve made a difference to a species…but it’s just one of thousands that need help,” Parrott says. “When an animal is added to the endangered species list, it will hopefully get more attention and more funding, and it needs that long-term care.
“But it also means they’ve gotten to the point where they need to be added to a dying list, and that’s quite devastating.”
Parrott believes that improving public knowledge of both the existence of species and the threats that exist in nature can improve outcomes for many animals.
This knowledge building can extend to people taking individual action – like providing appropriate food trees to support endangered animals that are losing their habitat, participating in citizen science programs, or even turning off outdoor lights to support endangered moths.
While the listing of species like the greater glider is a troubling occurrence, Parrott says it can serve to draw people’s attention to the challenges faced by lesser-known animals.
“Animals like the big glider are beautiful, they’re fluffy, and they can really grab people’s attention,” she says. “It’s great that they’re getting this attention, but we also have a lot of species that nobody’s ever heard of, like the pookila (New Holland mouse) and the bogong butterfly, which is also a very small animal, but an amazing species.
“Last week I saw gang cockatoos and grey-headed flying foxes in my own suburb – showing that these endangered species that are in trouble are actually around us [is important].”
Common Causes and Solutions to Endangerment
The challenges faced by large gliders are shared by these other lesser animals.
Although tackling climate change requires large-scale societal transformation, other actions can be taken to bring more immediate relief to native species.
Government conservation advice provided for all animals added or reclassified so far in 2022 indicates that clearing of land and vegetation poses a threat to survival. For gliders, this represents a catastrophic risk.
This is why shifting the forest industry to an entirely plantation-based sector is a critical solution that Lindenmayer says needs to be implemented, and soon.
“It’s time to abandon indigenous logging,” he says. “Western Australians did it: on December 31, 2023, [WA] will no longer exploit native forests.
“Victoria needs to do this at the same time, as does New South Wales. It is really important that we tackle this problem, which makes huge areas of forest unsuitable for animals like large gliders, either permanently or for periods of up to 200 years.
Lindenmayer also points out that the clearing of non-forest lands and the construction of coal mines in eastern states are adding pressure on threatened forest dwellers. But he also wants to see the government take biodiversity seriously.
“The federal minister can actually get seriously involved in this file and not untangle, but improve environmental laws, to ensure that more biodiversity is not lost. It’s essential.
Australia accounts for 35% of the world’s modern mammal extinctions. Over the past 200 years, about 10% of our terrestrial endemic mammals have disappeared.