The Australian government has confirmed that an ongoing series of mice plagues, which have devastated parts of the country’s eastern agricultural regions, are now spreading towards major grain export hubs. The development raises concerns for the UK’s new trade agreement with Australia, signed in December 2021, which allows for tariff-free imports of Australian wheat and barley.
According to the New South Wales Department of Primary Industries, the mouse population has exploded in the state’s Riverina region, a critical producer of wheat, barley, and canola. Farmers report crop losses of up to 20 percent in some areas, with rodents contaminating stored grain and damaging harvesting equipment. The plague has been exacerbated by a prolonged drought followed by heavy rains, which created ideal breeding conditions.
“The scale of the infestation is unprecedented,” said Dr. Sarah Johnson, a pest ecologist at the University of Sydney. “Mice are now moving into commercial storage facilities and transport infrastructure. The risk of contamination spreading through supply chains is significant.”
The UK-Australia Free Trade Agreement, which came into effect in May 2023, eliminates tariffs on Australian agricultural products over a phased period. British farmers have long warned that Australia’s lower animal welfare and pesticide standards could undermine UK biosecurity. The mice plague underscores those fears: residues from rodenticides used heavily in Australia may persist in grain shipments, raising food safety questions.
A spokesperson for the UK’s Department for Environment, Food and Rural Affairs stated that the government was monitoring the situation but had no plans to suspend imports. “We have robust border controls in place. Any consignment found to contain contaminants would be rejected.” However, industry groups note that border inspections are random and do not test for all potential contaminants.
The Australian Wheat Board has assured trading partners that it is implementing additional cleaning and fumigation protocols. But experts argue that repeated outbreaks suggest systemic vulnerabilities. The plague is now moving towards the port of Newcastle, a key terminal for bulk grain exports.
Singapore and Japan have already tightened import requirements for Australian grain. The UK may face pressure to follow suit, particularly as it negotiates other post-Brexit trade deals. “This is a test of the UK’s biosecurity framework,” said Professor Timothy Wilson, a trade policy analyst at King’s College London. “Allowing contaminated grain into the market without full assessment would set a dangerous precedent.”
The Australian government has allocated A$50 million in emergency funding for baiting and research. But with mice breeding rapidly, the window for containment is closing. For the UK, the immediate concern is not just economic but institutional: upholding standards that protect both consumers and domestic agriculture.
