Hundreds of sparrows have been discovered lying on central New Plymouth streets, and scores of them have died.
Between 50 and 100 of the birds died and a similar number were been successfully revived by the local SPCA.
The New Plymouth District Council spokesperson Lloyd Crow says the council received a number of reports of sparrows on the ground in the Devon Street East area on Friday morning.
Mr Crow says some of the dead birds have been taken to a vet clinic for testing to find out what caused their death, however he suspects it was from natural causes.
He says they may have died from from exposure in the heavy rain, and fallen from the roosting tree nearby, as most of the birds were young and their crops were empty.