A catastrophic mouse plague in eastern Australia has entered its fourth month, with infestations now threatening the country’s wheat exports to the United Kingdom. Farmers in New South Wales and Queensland report crop losses of up to 40 per cent, as rodent populations surge to levels not seen in decades.
The plague, which began in late 2020, has been exacerbated by a prolonged drought followed by heavy rains that created ideal breeding conditions. Mice have overrun grain silos, storage facilities, and farm equipment, contaminating supplies with faeces and urine. One farmer described the scene as “like a decaying body,” referencing the stench of rodent carcasses amid the stored wheat.
Australia is the world’s fourth-largest wheat exporter, shipping approximately 20 million tonnes annually. The UK imports roughly 1.5 million tonnes of Australian wheat each year, primarily for bread and biscuit production. The Department for Environment, Food and Rural Affairs has confirmed it is monitoring the situation closely, with contingency plans being drawn up to source alternative supplies from Canada or the European Union.
The economic impact is already severe. The New South Wales Farmers Association estimates the plague has cost the state’s grain industry AUD 1 billion ($560 million) in lost revenue. Exporters have been forced to divert shipments to lower-grade markets in Southeast Asia, where contamination tolerances are higher. The UK’s strict food safety standards may now exclude up to 30 per cent of Australian wheat imports.
Public health officials have also raised concerns about leptospirosis and other rodent-borne diseases. The Australian Department of Health has issued advisories for rural communities, urging precautions against contact with mice and their droppings.
Efforts to control the plague have so far been inadequate. Widespread baiting campaigns have been hampered by supply shortages of the anticoagulant poison bromadiolone. The Australian Pesticides and Veterinary Medicines Authority has granted emergency approvals for its use, but farmers report that mice are developing resistance. Aerial baiting has been proposed but faces regulatory hurdles and environmental opposition.
The federal government has announced AUD 50 million in emergency funding, including rebates on bait purchases and grants for on-farm storage upgrades. Prime Minister Scott Morrison described the crisis as “unprecedented” but stopped short of declaring a state of emergency, which would unlock additional resources.
For UK importers, the immediate outlook is uncertain. Shipping data from Port Kembla, Australia’s largest grain export terminal, show a 15 per cent decline in wheat volumes destined for Europe since March. The UK Flour Millers Association has warned of potential price increases for flour-based products later this year if the disruption continues.
The plague has also reignited debate over agricultural practices. Critics argue that the expansion of monoculture cereal cropping has created a perfect habitat for mice, while others point to the ban on stubble burning, which previously helped reduce rodent populations. The Australian Bureau of Agricultural and Resource Economics has called for a long-term integrated pest management strategy.
As the plague enters its peak season with the onset of winter breeding, the window for mitigating damage is narrowing. The UK’s reliance on Australian wheat, cemented by the recent free trade agreement, now presents a vulnerability in the nation’s food supply chain. For Australian farmers, the immediate battle is survival. For British consumers, the price of bread may soon reflect the cost of a country overrun by mice.
