Early results from this season’s monitoring of Mountain Pygmy-possum breeding in the Victorian Alps are indicating a turnaround in Pouch Young Litter Loss that has previously been linked to the species’ declining numbers.
Pouch Young Litter Loss is a condition that has been identified in surveys of the endangered Pygmy-possums during the past five years, coinciding with extremely low numbers of Bogong Moths in alpine areas. The moths are usually a key food resource for the possum during their breeding season.
The condition sees female possums with young suffer deterioriation in body condition – including severe weight loss – to the point where they can’t sustain their pouch young. The baby possums die and a new generation is lost.
Biodiversity Project Officer at North East Catchment Management Authority (CMA), Phill Falcke said during 2017 and 2018, surveys at most possum sites found half of the pouch young had died because their mothers had insufficient body condition to feed them.
“At some sites, up to 95 per cent of all the pouch young were lost,” he said.
Mr Falcke said North East CMA was delivering a major project to address the threats to the possum in the Victorian Alps.
This project is supported by the North East CMA, Parks Victoria, Mount Hotham Alpine Resort Management Board, Falls Creek Alpine Resort Management Board and DELWP, through funding from the Australian Government’s National Landcare Program and the Australian Heritage Grants Program.
Mr Falcke said a large part of the project covers monitoring of Pygmy-possum populations to understand how their numbers change from year to year.
It also addresses threats to possum including controlling the weeds that are invading their habitat, and removing introduced predators such as foxes.
“The ongoing monitoring was really important, because that’s how we noticed that Pouch Young Litter Loss was occurring,” Mr Falcke said.
“We were able to achieve additional funding to take a more detailed look at what was going on.
“When we monitored for Pouch Young Litter Loss over the possum breeding season between January and February this year we found almost all the female possums were in fair to good condition. They showed evidence of having successfully bred this season – meaning that Pouch Young Litter Loss didn’t occur this year.”
Mr Falcke said the 2021 results are believed to be due to a general increase in the numbers of Bogong Moths observed in the Alps this year.
He said genetic work now underway is analysing “Possum poo” to better understand the diet of the possums. This work will establish whether Bogong Moths alone are the major driver of Pouch Young Litter Loss, or whether there are other factors. This research is expected to be completed by the end of 2021.
“Being able to better understand how the possum numbers change based on the availability and type of food available will allow us to tackle and manage these threats in the future, making it more likely they will survive future challenges,” Mr Falcke said.
The North East CMA will soon release a video that examines the work being done to improve the possum’s future. It will be made available on the website at www.necma.vic.gov.au.