Australia: Will the mouse infestation ever end?
The biblical mouse plague ravaging Australia is showing no signs of letup, said Daniella White in The Sydney Morning Herald (Australia). The millions of mice now scurrying across the southeast have gobbled some $775 million worth of crops and are gnawing through anything in their path—including barns, homes, and even cars. A rural prison in the state of New South Wales was being evacuated this week because mice had chewed through ceiling tiles and wiring and their stinking dead bodies are piling up in wall cavities. Once the rodents start rotting, says state prison commissioner Peter Severin, “the next problem is mites.” Some 420 inmates and 200 staff will be relocated while the facility is purged, and more such evacuations could follow. Blame the British, said The Economist (U.K.). Australia was mouse free until British convict ships arrived there in the late 18th century, carrying both prisoners and rodents. The mice spread rapidly—a female mouse can bear a litter every month—and have been wreaking havoc ever since. The current plague is likely a result of this year’s heavy rains, which “allowed grain growers to plant the largest area of winter crop ever recorded.” With plenty of food in the fields and populations of their slower-breeding predators reduced by two years of drought and bushfires, the conditions were perfect “for a mass mouse-breeding season.”
The infestation is so severe “that mice are biting people in their beds, sending some residents to the hospital in a critical condition,” said Lucy Thackray in ABC.net.au (Australia). Dozens of people have contracted leptospirosis, a bacterial infection that if left untreated can cause kidney failure and meningitis. Farmers are baiting fields with the poison zinc phosphide, which is expensive and time-consuming, but the worst part is the ick factor. “Farmers and their families are unable to get a decent night’s sleep,” said John Warlters of the charity Rural Aid, “without mice chewing on toes and scampering across beds.” Some have resorted to placing the legs of their beds in buckets of water to stop mice from scuttling up in the night. Mice are even showing up in the stomachs of fish, said Matilda Boseley in The Guardian (U.K.). Freshwater Murray cod tend to vomit when they’re hauled into the boat, and these days the river fish are hacking up half-digested mice. The upside is that cod stocks, depleted by drought, are rebounding. The downside is that nobody wants to eat mice-gorged fish.
It’s going to be “a long battle,” said Peter Hannam in The Age (Australia). Population growth should slow now that the Australian winter has arrived. But “the mice are expected to return with renewed menace” when spring crops ripen. Some farmers had placed their hopes in New South Wales’ emergency appeal to the federal government to allow use of the banned poison bromadiolone, an anticoagulant known as “mouse napalm.” The federal government said no, because the bromadiolone would likely kill too much native wildlife. The plague will likely only end with the right combination of weather, food shortages, and rodent disease. Until then, farmers must cope with “the gruesome task of disposing of thousands of dead, stinking mouse corpses.”