At least 14 sulphur-crested cockatoos and a crimson rosella were poisoned last week in Wentworth Falls.
A spokesman for NSW Wildlife Information, Rescue and Education Service (WIRES), John Grant, said volunteers had collected 10 carcasses from a property in Dalrymple Avenue on Wednesday and a couple more from the street the following day.
They took the bodies to Taronga Zoo where experts confirmed that the birds had been poisoned, Mr Grant said.
The owner of the property, who didn’t want to be identified for fear of reprisals, said he believed poisoned seed had been thrown over his back fence.
“I saw this seed and everything seemed alright. Then I saw a little bird dead,” he said.
He also heard a car out the front and found a woman from WIRES who had responded to a call about a dead cockatoo.
He said some of the birds managed to fly away but one was caught in a nearby tree and hung in a branch by its wing. “When I next looked, it was gone,” he said.
The man said he occasionally put seed out for birds but never got more than a dozen cockatoos in his yard and no one had ever complained.
“You don’t throw poison into people’s yards,” he said. “It’s a cowardly act. And what if you’ve got animals or children?”
He said he had two cats himself who never went near the birds and he made sure they didn’t touch the seed.
He said he had raked up the seed and hosed the area down for about 15 minutes. Then he drafted a note about the poison and letter-boxed people in the street “to warn them”.
A spokeswoman for the Environmental Protection Authority issued a statement to the Gazette.
“Twelve sulphur-crested cockatoos and one rosella were reported dead in the vicinity of Dalrymple Ave, Wentworth Falls on Wednesday.
“National Parks and Wildlife Service, EPA, Department of Primary Industry, RSPCA, Taronga Zoo and NSW police have all been involved and investigations are continuing.”
Anyone with information is asked to call the environment line on 131 555. WIRES is on 4754 2946.