They’re back from the very brink of extinction
THE success of Mt Buller’s Mountain Pygmy Possum recovery program has been highly praised during the opening of the 2016 snow season.
Both ARMB board chair Jennifer Hutchison and chief executive officer John Huber mentioned the success of the program to reinstate a healthy colony of the tiny creatures that were in fear of extinction.
Ms Hutchison related how a ‘few male possums were borrowed from Mt Hotham’.
She said the success of these males being introduced, to boost the gene pool, had been so successful the ‘boys had been sent home early’.
Mr Huber also praised the work of the environmental team on Buller, in particular Louise Perrin, head of the environmental department.
“The mountain pygmy possum story at Mt Buller is a pretty rare example of where Australian threatened species management has succeeded,” Ms Perrin said.
“This past summer, as we undertook our standard monitoring, we were staggered by the numbers – we now have more than 140 mountain pygmy possums – more now than when they were first rediscovered in 1996.
It was initially thought the possum to be extinct, however, a live possum was found at Mt Hotham as early as in 1966.
“They are very small, live deep down in rock boulder-fields (not trees) in tiny habitat patches at high elevations and hibernate from May to October – meaning they are not often seen,” Ms Perrin said.
“Over the years, their habitat has been lost and/or fragmented (meaning loss of genetic diversity) and feral predators (particularly foxes and cats) have been happily munching on them.”
When they were re-discovered at Mt Buller in 1996, around 80 individuals were trapped.
By 2004, this number had dropped to six (bi-annual monitoring takes place in November and February) - extinction was imminent.
Resort management, with BSL and DSE (now DELWP) developed a recovery plan, which was implemented from 2005 to 2010.
Key actions were to connect previously fragmented habitat, revegetate habitat, undertake integrated yearround ongoing predator control programs, reduce sediment impacting habitat and to improve education and awareness of the species.
“By the end of 2010 we had rebuilt habitat using 4000 cubic metres of rock re-creating boulder-fields, installed 10 rock tunnels to link previously fragmented sites and planted around 75,000 food and shelter plants in key habitat areas,” Ms Perrin said.
“We had also developed, and continue to implement, our year-round predator control programs.
“Some 182 sediment traps were installed to catch sediment before it reached boulder-fields and we have established the mini habitat areas in the Village and at the Ski School to raise awareness of the species – along with information available on our websites and through brochures.
“By 2010, we caught 30 animals (remembering that snowgum woodlands which link the boulder-fields had been destroyed by fires in 2006-2007 burning 10 per cent of the boulder-field habitat).
“As population was not recovering as it should we developed the next recovery plan for the species – 2011 to 2016 - and began the next set of works.
“We’d collected genetic material (simply a hair sample containing the hair follicle) from each individual caught over the years of monitoring and the analysis of these samples revealed that although the population was growing, the genetic diversity was still low.”
This was the factor hampering the full recovery of mountain pygmy possums on Mt Buller and prompted the team to take control and undertake a novel in situ translocation project which involved wild-to-wild translocations of six male mountain pygmy possums from Mt Hotham to Mt Buller just as the breeding season started.
The following autumn, more than 50 per cent of the juvenile possums caught had a percentage of Mt Hotham genetics.
“In 2011, we had 48 possums so we were pretty sure we’d hit on the winning formula,” Ms Perrin said.
“We undertook another translocation the following spring with another six males – this time from Mt Bogong (to fully soup up the genetic diversity) and again saw terrific results the following autumn.”
Next on the agenda is the 2017-2021 recovery plan.
“We still have some work to do; we continue to revegetate habitat and we are looking at another novel approach (intra-site translocations) to establish populations in areas of habitat which are currently unused,” Ms Perrin said.
“It’s pretty cool that a small group of passionate people have been able to work together to get this species back on track at Mt Buller.
“And we are providing extremely valuable information not only for management of mountain pygmy possums in the wild in Australia, but also for threatened species management in general,” Ms Perrin concluded.
FLOURISHING: Mt Buller’s manager of environmental services Louise Perrin records details of the mountain pygmy possum population twice a year and is thrilled at the success of an introduced breeding program