North East Wildlife Control catcher Jeff Davies said conditions across the Goulburn Valley had been ripe for mice.
“The population has definitely grown — they've bred and bred and bred all of this year,” he said.
“It's been a really good harvest and there's all this grain sitting round . . . so mice are moving where the food source is.”
Recently, Mr Davies caught 30 mice on his Benalla property in just 36 hours.
“I got two mice in one trap in under an hour, with nothing attracting them apart from shelter and water.”
Mr Davies said with an increasing number of mice being found, he had also seen more snakes than usual at residential properties.
Although mice number are on the rise, Echuca's Ridley's Pest Control owner David Hodgens said it wasn't enough to call it a "plague".
“We've definitely seen an increase of mice around and I'd say it's ahead of when it normally is,” he said.
“We tend to get a rush around late-March or into April when everything has cooled down, but we started to see them come out in late February this year because the autumn weather has come early.”
An Agriculture Victoria spokesperson said the department was aware of increased mice populations in some parts of the state, but believed it was not widespread.
“Agriculture Victoria is closely monitoring the situation and supporting farmers with management advice,” the spokesperson said.
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