The parrot lives much of the year in Victoria and New South Wales where it feasts on the nectar of flowering gums. But when it migrates to Tasmania to breed, it comes under attack from predatory sugar gliders, research shows.

With an already slim population of less than 2000 birds, conservationists have warned that numbers could halve in just four years – and crash by as much as 87 per cent in three generations, according to findings outlined in a paper published in the journal Biological Conservation.

"These numbers are in free-fall," said Robert Heinsohn, a conservation biologist at the Australian National University. "The swift parrot has been skating on thin ice for decades – now it is just hanging on."

Professor Heinsohn said modelling showed that in 16 years the swift parrot could effectively be extinct.

He lodged a nomination with the Environment Department in Canberra on Thursday, which recommended upgrading the bird's current endangered status to critically endangered.

"It usually takes several months for this to trickle through the processes," he said. "But there is great urgency. If we act now we have the resources to deal with this."

If listed, the red-faced, luminous green bird would join just nine other Australian birds counted as critically endangered.

ANU post-doctoral fellow Dejan Stojanovic discovered the crisis was being caused by sugar gliders, which might have been introduced to Tasmania more than a century ago.

The nocturnal gliders are small enough to wriggle into swift parrot nest holes in gum trees, where Dr Stojanovic gathered evidence that they eat eggs, young and even brooding adult birds.

"The gliders go for pretty much anything they can find," Dr Stojanovic said.

Although swift parrots roam widely through the south-east Australian mainland as they seek gum blossom, in Tasmania they are confined to a band of eucalypt forest on the east coast under pressure from logging.

"To prevent total population collapse in swift parrots, we need to urgently reassess how forests are managed in Tasmania," Dr Stojanovic said.

"Preventing further de-forestation in core swift parrot breeding areas is a basic first step towards avoiding catastrophic population collapse."

BirdLife Tasmaniasaid the models and projections in the Biological Conservation study were conservative, because they focussed on glider predation and did not include other factors such as loss of habitat.

The group's convenor Eric Woehler called for an immediate halt to all logging in swift parrot habitat.

Environment Tasmania this week published a report showing the state government approved logging in five coupes that were swift parrot breeding habitat, despite strong internal scientific advice against it.

The Federal Government's Threated Species Commissioner Gregory Andrews said he was consulting widely on solutions to turn around the swift parrot's decline.

"The Australian Government's $30 million National Environment Science Program's Threatened Species Recovery Hub has a proposal to examine the impacts on swift parrots of sugar gliders," he said. "I am considering that proposal closely."