If it walks like a duck, swims like a duck, and quacks like a duck – it's probably a duck.
And if you can see a lot of them – you may well be in Stowmarket.
The mid-Suffolk town has long had a large population of mallards which can be seen wandering around the town centre and holding up traffic.
Mayor Keith Scarff says the birds have been ever-present during the 30 years he has lived in the town.
He said: "It's always fun to see them.
"They hold the traffic up sometimes when they cross the road. You see the traffic stopped and think 'why's the traffic stopped?'.
"Then you see a parade of ducks crossing the road, completely oblivious to the fact that they're crossing a highway and if somebody hadn't stopped it would've been a massacre.
"They bring a cheer to people when they see them.
"I think they'll appear anywhere people lay food out for them and lots of people do lay food out for them – I know the youngsters like feeding them.
"But they do have their favourite haunts."
According to Suffolk Wildlife Trust artificial feeding can increase duck populations to such an extent that they damage natural habitats.
The wildlife group warns that artificially feeding ducks on a small body of water can "lead to visually unattractive muddy ponds devoid of plants and species-poor habitats".
However, Mayor Scarff said there may actually be fewer ducks in the town at the moment than in past years.
"I go down to the river quite regularly with the Pickerel project and from our experience we haven't seen as many down in the river," he said.
"There's usually quite large numbers in between Station Road and up to the bridge.
"They quite often get up as far as behind Barnards but we haven't seen quite so many – maybe they're in town doing other things."
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