Australia mouse plague spreads towards South Australia farms, experts warn

A mouse plague has hit Australia with billions of dollars of cops at risk. Photo / CSIRO

Farmers in Australia are facing plague levels of mice with favourable breeding conditions leading to an explosion of rodents.

Steve Henry, who researches mice and their effect on farming for the Commonwealth Scientific and Industrial Research Organisation, said mice had reached “well above plague levels” in Western Australia and were surging in the south, he told the Guardian Australia.

“That’s real cause for concern. It’s a plague under any circumstances.”

Plague levels are reached when there are more than 800 rodents per hectare, according to Henry.

“When we see a plague, it’s more like a whole lot of satellite populations growing and growing until they all join up,” Henry said.

Australia's Mice Alert website shows the spread of the plague. Photo / Mice Alert

Speaking to 9News, Henry said farmers were resorting to burning their crops or trying to shoot the mice.

The farmers have already been hard hit by wild weather and are operating in a fuel crisis.

Experts said the plague could threaten Australia’s A$3 billion ($3.6b) grain and food exports.

Andrew Weidemann, from Grain Producers Australia, told the outlet it was devastating for everyone.

“This is another kick in the guts, not only for our farmers impacted, but it’s the community, it’s anybody. It’s small business, it’s supermarkets, it’s the baker,” he said.

Western Australia’s wheatbelt region is already in the grip of the plague, which is now spreading towards South Australia – a state still recovering from heavy rainfall and flooding.

Writing in the Conversation, associate professor in wildlife conservation Robert Davis said mouse plagues often occur after cyclones and floods. Conditions became ideal for mouse populations, with warmer temperatures and abundant crops providing food and shelter.

He said this event was an “unsettling reminder” of the mouse plagues of 2020 and 2021 throughout Australia.

A mouse plague has hit Australia with billions of dollars of cops at risk. Photo / CSIRO

While mouse numbers have exploded in Australia, New Zealand farmers don’t need to reach for the gun or burn their crops.

Professor Carolyn King, an expert on conservation and pest control from the University of Waikato, said New Zealand didn’t have the conditions or enormous wheat farms like Australia.

However, King said New Zealand was still vulnerable to mouse plagues during a mast year when southern beech trees drop their seeds at the same time, which happens about every three to four years.