It's a perfect storm. Viruses that have controlled rabbits for years are now only about one-third as effective as they once were and the best season in years has rabbit numbers soaring.
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But there was nothing in the federal budget for the national rabbit biocontrol program, which runs out of funding on June 30, jeopardising research into new measures.
Back when the myxoma virus or "myxo" was released in 1950, it killed 99.8 per cent of infected rabbits.
Since then, the effectiveness of Australia's rabbit control viruses has been dwindling. The 2017 release of RHDV1-K5 knocked down just 34pc of rabbits.
In eastern Victoria, Procull's Dave Rowlands can't keep up with demand.
"The virus just isn't working or the rabbits have become immune to it, but we've got rabbit work coming out our ears and the proverbial at the moment," he said.
It reminds the 54-year-old of his childhood on a West Gippsland dairy farm when, aged 6, he learnt to shoot rabbits until myxo brought them under control.
Now, Mr Rowlands is out again with his own daughter, shooting hundreds of rabbits a night.
West of Broken Hill at Thackaringa Station, grazier David Lord is seeing numbers explode, too.
In 2002/03, he ripped about 28,000 warrens on his 66,000-hectare station using D5 and D8 bulldozers.
It cost "more than buying out the neighbours", Mr Lord said, but together with biocontrols, that work held the local population at bay for years. The results were so dramatic, he took photos to document the change.
"That vegetation came up during the Millennium drought," Mr Lord said.
"There was very limited rainfall. The only thing that was different was we had removed the rabbit."
Now that the drought's broken and the insects are back to carry the viruses, rabbit numbers should be under control.
"I'm not seeing the numbers decline," Mr Lord said. "Now, that's really, really scary."
Rabbits are developing a natural immunity to the haemorrhagic viruses and, ironically, well-intentioned land managers are making things worse.
Releasing a haemorrhagic virus during breeding season can be disastrous because rabbits less than 10 weeks old won't die. Instead, it provides life-long immunity to the virus.
New research by the University of NSW showed that 74pc of releases in Australia were done at the wrong time.
In a good season like this one, rabbits could breed year-round, creating a double whammy of ballooning populations and immunisation created by mistimed releases.
That, Centre for Invasive Species Solutions chief executive Andreas Glanznig said, was why his centre wanted to reintroduce a national coordinator.
"That new evidence highlights how we're not getting the best value from the biocontrol agents that we have at the moment," he said.
It's all created a race between the growing immunity of the rabbits and the development of new virus strains.
Scientists have begun culturing viruses in petri dishes rather than in rabbits, hoping they will find new mutations that might evade immunity quicker.
Once a breakthrough is made though, it can still be years before any new control measures are allowed to be implemented.
"Not only have you got to do the science, then you're going to spend three years or so working through all these regulatory and policy approval processes," Mr Glanznig said.
But hopes of a long-term solution are now pinned on a new form of control: genetic infertility. The question is whether there's enough long-term funding to match, Rabbit Free Australia chairman Adjunct Professor Wayne Meyer said.
"Given the kind of decreased effectiveness associated with viruses, you could see very large numbers of rabbits coming again within a decade," Adj Prof Meyer said.
Thackaringa's David Lord said there was no "plan B" without effective biological controls.
"The government's going to drop the ball by removing funding from biocontrol and what we did in terms of mechanical habitat destruction is not possible in a lot of parts of Australia," he said.
The National Farmers Federation had lobbied for a $10 million a year investment in the Centre for Invasive Species Solutions over the next five years to be included in the federal budget but nothing was announced.
A government spokesperson said a rabbit biocontrol strategy report by the Centre for Invasive Species Solutions would receive further consideration.
The federal government was investing over $650,000 until June 2024 in rabbit biocontrol research with the NSW Department of Primary Industries that would test rabbit haemorrhagic disease virus delivery methods.
While virus delivery methods were important, Adj Prof Meyer said, it was essential to find totally new methods of controls as rabbit immunity strengthened.
"Unless you've got something in the pipeline and being worked on for 10 years from now, you're simply not going to have anything to replace them," he said.
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Marian Macdonald
Writing for farmers in the Stock & Land, The Land, Queensland Country Life, Stock Journal and FarmWeekly, farming in Gippsland.
Writing for farmers in the Stock & Land, The Land, Queensland Country Life, Stock Journal and FarmWeekly, farming in Gippsland.
