Plague of mice threatens huge tracts of land in Australia

Vast tracts of land in Australia’s New South Wales state are being threatened by a mouse plague which was described by the state government as “absolutely unprecedented”.

Just how many millions of rodents have infested the agricultural plains across the state is guesswork.

One family blamed mice chewing electrical wires for their house burning down.

Agriculture minister Adam Marshall said this month: “We’re at a critical point now where if we don’t significantly reduce the number of mice that are in plague proportions by spring, we are facing an absolute economic and social crisis in rural and regional New South Wales.”

“We just sow and hope,” he said.

The risk is that the mice will maintain their numbers through the Southern Hemisphere winter and devour the wheat, barley and canola before it can be harvested.

NSW Farmers, the state’s top agricultural association, predicts the plague will wipe more than one billion Australian dollars (£547 million) from the value of the winter crop.

Critics fear the poison will kill not only mice but also animals that feed on them, including wedge-tail eagles and family pets.

Mr Marshall said: “We’re having to go down this path because we need something that is super-strength, the equivalent of napalm to just blast these mice into oblivion.”

The plague is a cruel blow to farmers in Australia’s most populous state who have been battered by fires, floods and pandemic disruptions in recent years, only to face the new scourge of the introduced house mouse, or Mus musculus.

The worst comes after dark, when millions of mice that had been hiding and dormant during the day become active.

By day, the crisis is less apparent. Patches of road are dotted with squashed mice from the previous night, but birds soon take the carcasses away.

Haystacks are disintegrating due to ravenous rodents that have burrowed deep inside. Upending a sheet of scrap metal lying in a paddock will send a dozen mice scurrying. The pavements are also strewn with dead mice that have eaten poisonous bait.

But a constant, both day and night, is the stench of mice urine and decaying flesh. The smell is people’s greatest gripe.

“You deal with it all day. You’re out baiting, trying your best to manage the situation, then come home and just the stench of dead mice,” said Jason Conn, a fifth-generation farmer near Wellington in central New South Wales.

“It doesn’t relent, that’s for sure.”

Colin Tink estimated he drowned 7,500 mice in a single night last week in a trap he set with a cattle feeding bowl full of water at his farm outside Dubbo.

“I thought I might get a couple of hundred. I didn’t think I’d get 7,500,” Mr Tink said.

Mr Barnes said mouse carcasses and excrement in roofs were polluting farmers’ water tanks.

“People are getting sick from the water,” he said.

The mice are already in Mr Barnes’ hay bales. He is battling them with zinc phosphide baits, the only legal chemical control for mice used in broad-scale agriculture in Australia. He is hoping that winter frosts will help contain the numbers.

But then, the pandemic brought a labour drought. Fruit was left to rot on trees because foreign backpackers who provide the seasonal workforce were absent.

Plagues seemingly appear from nowhere and often vanish just as fast.

Disease and a shortage of food are thought to trigger a dramatic population crash as mice feed on themselves, devouring the sick, weak and their own offspring.

Government researcher Steve Henry, whose agency is developing strategies to reduce the impact of mice on agriculture, said it is too early to predict what damage will occur by spring.

He travels across the state holding community meetings, sometimes twice a day, to discuss the mice problem.

“People are fatigued from dealing with the mice,” Mr Henry said.