"They are on the back doorstep every morning, jumping up and down for their breakfast. They have a paddling pool in the back garden to swim in. They are also about a week short of having their final flight wings."
With help from neighbours, he went out and cleaned up the scene of the impact.
They took the injured bird to New Zealand Bird Rescue Charitable Trust, who then shifted it to a veterinary clinic. The duckling had been stitched up and was back with Valentine-Burt on Sunday, being nursed back to health in a big dog crate.
The SPCA had not been informed of the incident.
Valentine-Burt described the offending car as being dark in colour. After allegedly hitting the birds he said the car turned around and came back down the road, its occupants yelling something before driving away.
The incident was also "ironic", he said, in that a month or so ago the local business association had provided him with a professionally made "Ducks Crossing" sign.
It had lasted only a week before it was stolen - though Valentine-Burt doubted it would have stopped the group from mowing the birds down.
His road had multiple speed bumps along it, so it would have been an effort for the driver to get up the speed he was travelling at.
"He would have had to slow right down for the judder bar, then floor it to get up to the speed they were going when they drove through the ducklings."
Valentine-Burt called the incident "savage". He was disappointed no one had managed to gather the details of the car the youths were driving, and wanted them held to account.