More rodents than ever before are being spotted in broad daylight, scuttling across roads in the town centre and scampering along Oban's beaches.
The Black Lynn, where youngsters feed the ducks, is particularly worrying, says community councillor Dougie Graham.
'They [the rats] are not shy and they are big,' he said. 'One woman even stopped her car in George Street to let one cross,' he added.
'It's an epidemic. The problem has got very bad. I don't think it's just a coincidence. They are swarming and scary. The community council is worried and wants to know what the council's environmental health department is doing about it.
'These things spread diseases. What happens if a child drops a toy where one has urinated or if children who run their hands on the rails by the Black Lynn catch something terrible?
'We are looking for answers to what can be done,' said Mr Graham.
Argyll and Bute Council has not had an increase in complaints about rats.
A council spokesperson said: 'Our teams work hard to keep our communities free of waste, but everyone needs to play a part.
'We encourage everyone to follow some basic steps to control pests, including rats, by denying them access to food. Bag up waste properly, keep lids on bins and keep them clean, and don’t drop food on the ground.
'If you feed wild birds, consider stopping for a while or at least move the feeders about regularly.'
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