The squirrel glider relies on hollow old trees for shelter, and feeds at night on insects as well as pollen, nectar and sap.
There are few documented sightings of this species in the Seymour area in the past 30 years.
Ecologists have confirmed the presence of the glider on Ms Buchanan’s property.
Chris Pocknee from conservation group Biolinks Alliance said the squirrel glider was an exciting find.
“There is only one record from 2009 just outside of Seymour, and you have to go back to the 1990s for the next most recent handful of records in the area,” Mr Pocknee said.
“As a threatened species, every record is significant as we try to piece together a clearer picture of where these gliders are in the landscape.
“We hope to get out and survey more of the surrounding area to get a better understanding of the species.”
BEAM Mitchell Environment Group president Peter Lockyer said one of the main threats to this protected species was the fragmentation of habitat.
“This patch of bush is rich in wildlife and should be something we look after for generations to come,” he said.
“We are calling on Mitchell Shire Council to have a good look at how we can protect this area as parkland so that amazing species like the squirrel glider can be safe in their habitat.
“It’s up to us to make sure we look after the spot that this local population is living in.”
The sighting of the squirrel glider has been registered with the Victorian Biodiversity Atlas, a project that tracks wildlife records across the state.