When Dean Heinz and Ian Mansergh enter the Viking Lodge in Falls Creek they stand out.
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The pair have a look of sun bleached clothing and skin, something which can only be attained through extensive fieldwork.
Bypassing a tired group of 47 La Trobe university students, who have started their first day of intensive one-week course on alpine ecology, the two scientists steal into the kitchen and fix up some peanut-butter on toast after a long evening of setting traps.
Heinz and Mansergh had set 50 “Elliott” traps, all manufactured by 90-year-old Victorian Joyce Elliott, for a monitoring program in the habitats frequented by the endangered mountain pygmy possum.
The largest of all pygmy possums, the burramys parvus is the only Australian mammal restricted to mountain landscapes and the only native marsupial which hibernates under the cover of snow.
It can grow to about 11 centimetres in length with a pink ratty tail which can be 14 centimetres long.
Their distribution area consists of small community pockets found in the high altitude regions of Kosciuszko National Park in NSW and places like Mount Higginbotham, Mount Loch, the Bogong High Plains, Mount McKay and Tim’s Spur in Victoria.
In recent years the rare critter has become the face of species recovery in Victoria.
First thought extinct and then rediscovered in the 60s, the possums’ numbers have always been low.
In the mid-2000s, however, things got bad according La Trobe adjunct professor Mansergh who has studied them since 1979.
He said the Mount Buller population, which had been isolated for at least 15,000 years, nosedived.
At first it was thought to have been caused by feral pests but Mansergh said it became apparent something else was at play.
“Because of the ski resort there, habitat fragmentation and destruction the population went from 350 in 1996, and genetically healthy ... down to about 30 animals (in 2009) and was genetically very unhealthy, it had become inbred,” Mansergh said.
In 2011, Heinze, who has mostly taken over the work started by Mansergh, introduced six males from Mount Hotham to bring the population back from the brink.
It was a dramatic move.
Heinz said there had been political and scientific opposition to such a play, given, there was in fact a genetic difference between the Mount Buller possums which had been isolated for thousands of years from other members of its species.
The argument against breeding two genetically different animals was the loss of the uniqueness of one, while people like Heinz and Mansergh argued without it the Buller possums would disappear altogether.
Eventually the project was approved and it didn’t take long for positive results.
After the first breeding season in 2011 researchers found 16 hybrid juveniles.
Five years on and Mansergh said the trans-location of the Hotham boys had meant the complete restoration of the Buller population.
“Captive breeding essentially failed to produce animals it thought it could,” he said.
“So this wild-to-wild trans-location we now call gene pool mixing … over time it meant the population could expand and be genetically healthy, so that means they've got a great capacity to adapt to change.”
Morning time at the Viking Lodge and toast gets a re-run for breakfast.
Heinze and Mansergh head off in the early light in a dusty navy-coloured Landcruiser, leading a convoy of students strapped into bus seats.
The vehicles snake along gravel roads into the high plains near Pretty Valley.
It’s too cold on the top of the alps for many trees to grow.
Instead there are grasslands, once grazed by cattle, they are still a food source for wild horses and deer.
The possum men drive ahead of the student group to check their first set of traps while the undergraduates, a few minutes behind, walk up the road used by park management and horse riders.
Heinze and Mansergh stop at what looks like a rock slide.
The former explains the boulder fields are basalt and were formed by the freezing and thawing of rocks thousands of years ago, which geologically speaking isn’t all that long ago.
Mansergh said between the gaps of the many rocks and under the cover of plant growth is where the possums most like to be.
“It's a three dimensional habitat, it has a lot of spaces in the rocks, this is where the Bogong moths fly up to aestivate,” he said.
Heinze further explains how the moths breed on the plains of Queensland and NSW.
“They migrate to the alps to escape the heat, and the place they go is in these boulder fields where they are safest, well presumably,” he said.
“Because there is a species here that knows they are coming here and they harness that enormous amount of food.
“The key thing about alpine animals is being able to live somewhere where they can move around and are not exposed to the harsh temperatures.
“In the rocks (under snow) the temperature is around two degrees, up above temperatures get to minus 20.”
The hinged metal contraptions used to catch the pygmies have been placed in the small crevices, all with a single walnut left inside as bait.
So this wild-to-wild trans-location we now call gene pool mixing … over time it meant the population could expand and be genetically healthy, so that means they've got a great capacity to adapt to change.
- Ian Mansergh
Heinze said most people did small mammal surveys with peanut-butter, which tasted good but was a “pain in the arse” and attracted ants.
Most of these traps were empty, save for a few bush rats so the troupe pushes on to the second trap site.
Heinze says the group were pretty much guaranteed to find a possum there.
After checking about six traps he has already collected three possums including a juvenile.
Heinze tagged 20 animals at the site in a previous year, and the juvenile was a good sign things were progressing as he would take a DNA sample to check its genetics and make sure there’s not another situation like Buller developing.
The small creatures are sensitive but rugged according to Mansergh.
The second site was touched by bush fires a few years ago.
Mansergh said some of these fires were supposed to have been once in a generation.
“Yet we've had three major fires in a decade,” he said.
“I believe that's consistent with a changing climate.”
The animals can recover to an extent.
Heinze, however, said climate change could prove to be a death by 1000 cuts type scenario for the possum.
Warmer temperatures could mean less snow cover and more airflow which would waken the possum too early from its hibernation meaning it would have to find more food which could be scarce.
What happens to mammal’s main food source, the moth, and a higher frequency of fires could also affect it.
As long as researchers like Heinze and Mansergh are around, the possums’ future doesn’t look too bad.
Heinze is working on a second “tunnel of love” at Mount Higginbotham which provides a corridor for the males.
They live in lower alpine sections, to the females, which live near the top.
Mansergh likens the tunnels to the trans-location program except over a shorter distance and within the same population.
“I’m absolutely proud to have been associated with the burramys.
“It’s been good for conservation to have positive stories, it’s a beautiful animal.”
It seems the life-work of these two ecologists could lead to even more positive stories for endangered species.
The success of the possum trans-location project will use a similar idea to link Tasmanian specimens of the Eastern Barred Bandicoot with their Victorian counterparts which have been flat-lining, in a study by the University of Melbourne’s Andrew Weeks and Heinze.