The footage from New South Wales is hard to watch. Grain silos turned into writhing carpets of fur. Tractors infested with nests of pink, hairless young. Farmers sweeping up buckets of dead mice from their kitchens, their faces etched with exhaustion and despair. Australia is in the grip of one of its worst mouse plagues in living memory, and while the crisis is unfolding 10,000 miles away, British farmers and policymakers are watching with a growing sense of unease.
For decades, the UK has looked to Australia as a bellwether for agricultural extremes. The drought that flattened the Murray-Darling basin in 2019 gave British growers a preview of what a warming climate could mean for their own wheat yields. Now, the mouse plague poses a different kind of threat: a biological eruption triggered by a perfect storm of weather conditions, chemical resistance, and the loss of natural predators.
The scale is staggering. Farmers in the Riverina region report mouse densities exceeding 1,000 per hectare. The rodents have devoured standing crops, chewed through irrigation pipes, and gnawed the wiring of combines. One grain grower near Dubbo told me he lost 20 per cent of his harvest in a single week. The financial toll is estimated at A$100m and climbing.
“It’s a plague born of plenty,” says Dr Emily Hogg, a biologist at the CSIRO who has been tracking the outbreaks. “A wet spring and summer produced abundant grain and grass seeds. Then a mild winter meant the mice kept breeding through what should have been a lean period. They don’t stop until they run out of food or a disease sweeps through the population.” But the bomb has been ticking for years. Overuse of broad-spectrum pesticides has decimated the insects and spiders that would normally keep mouse numbers in check. Meanwhile, the mice themselves are developing resistance to the anticoagulant poisons farmers rely on. Some populations now require 10 times the standard dose to be lethal.
For British farmers, the warning signs are clear. Our climate is becoming more volatile. The wet summers of 2019 and 2020, followed by a dry autumn, created conditions not unlike those that preceded Australia’s 2021 outbreak. “We have the same species here, the house mouse and the field mouse,” says Prof Jeremy Gray of the University of Reading. “The difference is that we have taken out many of the hedgerows and wild areas that used to host their predators. We have made the landscape friendlier for mice.”
The government’s own surveillance suggests a steady rise in rodent activity on UK farms. The Campaign for the Farmed Environment has warned that the loss of habitat for barn owls, kestrels and foxes is leaving crops more exposed. But the lessons from Australia go beyond ecological management. The plague has exposed the vulnerability of modern supply chains. With grain stored on farms for longer periods due to volatile markets, the rodents have found a year-round buffet.
“We cannot pretend this is just a problem for the Antipodes,” says Tom Bradshaw, vice president of the National Farmers’ Union. “The same pressures are building here. If we get two back-to-back mild winters, we could face an event that would make the 2003 outbreak in East Anglia look like a minor inconvenience.” That outbreak cost the UK an estimated £50m in damaged crops and control measures.
But there are glimmers of hope. One Australian farmer I spoke to, a fourth-generation grower near Wagga Wagga, has turned to an ancient remedy: encouraging feral cats. “We’ve put up nesting boxes for owls and left patches of long grass for the foxes,” he said. “It’s not going to stop a plague on its own, but it buys you time.” The UK’s own rewilding movement, focused on restoring predators, could provide a similar buffer.
The bigger question is whether our agri-environment policies are moving fast enough. The Environmental Land Management scheme, which pays farmers for green practices, could incentivise the creation of predator corridors. But critics say the payments are too slow to arrive, and the schemes too bureaucratic, to change the trajectory in time.
As I write this, the mice in Australia are still breeding. The winter has brought no respite. Scientists are now modelling the risk of a second wave next spring. And across the farming world, from the wheat belts of Western Australia to the barley fields of Yorkshire, the same question hangs in the air: are we next?
