The team aimed to create something the possums would like, but not love—more gym protein bar than sweet treat, Parrott says. Trials with captive possums confirmed that the animals would eat the bikkies only if they couldn’t get their bogong moths or other natural foods.
In November 2019, Parrott’s team successfully tested their concoction in the wild among the struggling possums in the Victorian boulder fields, using a variety of different home-made feeders. But it wasn’t until January 2020 that the bikkies really proved their worth. That month, Parrott got a call she would never forget. It was Linda Broome, and she didn’t even say hello. “It’s gone,” Broome said. “There’s nothing left.” Bushfires sweeping across vast areas of Australia’s southeast had hit northern Koscuisko National Park, near Cabramurra. The area’s tinder-dry boulder fields were home to a thriving population of mountain pygmy possums that Broome and her team, including PhD students Hayley Bates and Haijing Shi, had discovered in 2010.
Broome knew the possums had likely survived, deep in the damp crevices. But when she visited days after the conflagration, she found the still-smoking hillsides devoid of vegetation and insects for the animals to eat, and no water for them to drink. “Please tell me your food and your feeder worked?” Broome asked Parrott. It was one of the proudest moments of Parrott’s life that she could say yes—that the prototypes had been successful, and that they were ready to deploy.
The Zoos Victoria team sent bags of bogong bikkie mix and prototypes of the feeders to Broome, and the volunteers got making and baking. Every week for the next two summers, the National Parks and Wildlife Service Discovery Rangers, aided with baking by local school children, delivered fresh bikkies to 60 feeders stationed across the burned boulder fields.
By the end of 2022, the animals were thriving without support. “On one of the sites, almost every trap had possums,” says Bates, now an ecologist at the University of New South Wales. Vegetation was returning only slowly, but other prey like bugs and beetles were already crawling around the boulders. The expensive, labor-intensive experiment had worked—proving that in extreme situations, audacious interventions can stave off disaster for endangered species. Unfortunately, the need for them will only rise.
Bushfires are natural in Australia, but their frequency and intensity are predicted to increase as the climate warms. Alpine ecosystems in particular require a long time to recover, especially from consecutive burns. In 2003, for instance, bushfires burned right over the top of Mount Blue Cow. Twisting, skeletal forms still writhe among the boulders—the bleached bones of mountain plum-pine, another favored food source for the possums. Broome transplanted seedlings to replace them, but two decades later, even though the recent fires spared Mount Blue Cow, they’re only just beginning to take.
Then there’s the snow—the emblem of the high country, and the source of the water that feeds the fens and the streams. Snow depth and the number of snow days have been declining in Australia since the 1950s, and climate scientists warn that, by the end of the century, the Snowy Mountains may no longer live up to their name.
“The outlook for the alpine zone as we know it is pretty bleak,” says ecologist Lesley Hughes, an emeritus professor at Sydney’s Macquarie University, IPCC report author and director of the Climate Council of Australia. Even before it’s gone completely, dwindling snow cover will disturb the possums’ winter rest. A thicker layer of snow provides more insulation; without it, the animals’ nests get colder, which could wake them from hibernation before moths arrive or seeds are available, Broome says. Snow is also a barrier to predators, and warmer winters allow feral cats and foxes to range more freely and hunt possums more easily. In 2002, Broome asked rangers to start trapping and killing cats at Mount Blue Cow. They caught 30 that first winter.