The council had a number of the South American birds removed in 2006 during the Environment Agency's flood defence work on the Waits and is keen not to have more arrive in the town.

The council says duck droppings are making a mess of the scenic riverfront. They have been looking into having ducks, which originally escaped into the wild from farms where they were bred for meat, relocated to a sanctuary in Bedfordshire. However, instead of numbers going down the sudden arrival of the ducklings has seen the population grow.

Town clerk Alison Melnyczuk said: "We definitely don't want any more of them. They may look nice, but they make an awful mess.

"We do have a problem with people bringing them into town. Some have been let loose this week which is a major concern because the town and district council have to clear up after them. We believe some have made their own way back, but someone has been bringing them in, although we have no proof."

The clerk explained the council was looking into ways to relocate more of the ducks and added: "We're talking to RSPCA about having them relocated. We don't want any harm to come to them."

The RSPCA told the Town Crier that they would not get involved just because the ducks were unwanted, only if there was an immediate threat to their welfare, as with the flood defence project.