Five hundred million dollars has been lost at the farm gate due to mouse plagues which have devastated parts of NSW, according to a preliminary estimate.
That figure is expected to exceed a billion dollars as the natural disaster continues and farmers abandon their crops, according to NSW Farmers vice president Xavier Martin.
"The flow-on-effect in the NSW and Australian economy is likely to be in the region of three to four billion dollars even if we could get on top of this plague quickly," he said.
"At the moment that's not happening."
A rolling survey by the state's peak farming association of more than 1100 primary producers found 40 per cent will reduce their winter crops, including barley and canola, due to concerns about the plague.
Beer production is just one of many industries which could be impacted in the coming months due to a lack of grain.
The majority of farmers surveyed said despite having used rodent bait to combat the plague, they have still suffered heavy losses to machinery, crops and stored grain.
The cost of poisons has been high, with farmers spending thousands on baits, and close to 80 per cent saying the cost of purchasing them has increased.
Only 30 per cent said their health has been directly impacted by the plague, but over 90 per cent said they were concerned about illness if their homes became unsafe from infestation.
Nearly all farmers said the influx of mice had left them stressed, with many saying it had impacted their sleep, social interactions, finances and general outlook.
'Dysfunctional': Concern about NSW government response to mouse plague
Mr Martin said the hesitancy shown by many members to plant winter crops as planned is in part a consequence of the NSW government's "impractical and dysfunctional" response to the plague.
"I've had members say to me until the mice come to (Agriculture Minister Adam) Marshall's door, he's not going to realise," Mr Martin said.
Despite the government announcing a $50 million support package, rebates for the purchase of baits applying to households and commercial businesses will not be available until July, and they will not be extended to primary producers.
Instead, Minister Marshall's plan for affected farms is to ask the federal government for an exemption to use a deadly restricted, rodenticide bromadiolone, on a massive broad-acre scale.
The poison is usually restricted to domestic use because it can enter the food chain and kill pets, livestock and wildlife.
Farmers are currently using an average of 70 tonnes of zinc phosphide a day, an agricultural poison that generally kills mice within an hour, and leaves the environment quickly.
According to Mr Martin many NSW Farmers members expressed concern about using bromadiolone outside federal guidelines, as proposed by Minister Marshall.
"The way our members stay in business is to trust the science," he said.
"When we see a minister politicking the science, our antennae go up as to just what is going on."
Agriculture Minister Adam Marshall has been contacted for comment.
'Catastrophic': Mice take emotional and financial toll on farmers
Coonamble farmer David Chadwick told Yahoo News Australia his northern NSW community was impacted between August and March, costing him hundreds of thousands of dollars due to crop losses.
Locals had been pinning their drought recovery on a bumper crop this year, prudently storing reserves for the next one, but for many the mice devoured it all.
“It was catastrophic, financially and emotionally for a large number of people,” Mr Chadwick said.
“The sadness of it was our first opportunity to build some serious fodder reserves (since the drought) and it’s cleaned us out.”
For four months, Mr Chadwick said he was filling up a 20 litre drum twice a day with dead mice.
Dogs dead, houses stinking, mice caught in women's hair
Coonamble farmers have reported that the “stink” of mice has permeated everything. They broke into homes, defecating and urinating on everything - socks, underwear, shirts and trousers were all left soiled by the vermin.
Some women in the community were sleeping in their cars because mice were getting tangled in their hair as they slept.
“For anyone not living here, it’s impossible to grasp the concept of a mouse plague,” Mr Chadwick said.
Farmer Adam Macrae bailed 2300 bails of hay throughout October and November at his Coonamble property, and buried 500 in February as part of an effort to drought-proof his future.
He was left devastated by the loss of the majority of those bails to the plague.
"You try not to think about it, all that effort everyone went to," he said.
"It was beyond people's capacity to do anything about it.
"We may not feel it right now, but a little later down the track when we've got hungry cattle and not much feed in the paddock we will.
"Those reserves keep the businesses running, and keep people employed as well, and without that small rural communities suffer."
Across in Tamworth, farmer Mark Walters was devastated by the drought, but has downplayed the impact on his own farm.
While he wasn’t as badly affected as others, nonetheless the toll was still immense.
Despite aerial baiting around his crops, the mice have persisted.
Even worse, he is one of a growing number of farmers to have lost a pet dog to rat bait.
“Bloody hell that ripped me apart, my little mate” he said.
“But compared to other people I’m okay.”
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