The native parakeet, the Kakariki, has caused excitement amongst researchers after breeding on Motutapu in Auckland's Hauraki Gulf.
The population of Kakariki was released on near-by Motuihe and researcher Luis Ortiz Catedral said a group of the birds were spotted on Motutapu last week.
"I trust parakeets will become the most noticeable bird in the Hauraki Gulf in no time," he said.
Mr Catedral said only one of the birds had a metal band attached to a leg and therefore came from Motuihe.
"The surprising thing is that they have started breeding," Mr Catedral said.
He said the birds were released on Motuihe because it is pest free and could act as a starting spot for Kakariki breeding.
"They will become more and more common as time goes by," he said.
Mr Catedral said he is hopeful that the birds will be established on Motutapu after the breeding season and he will do a count in March when juveniles can be seen.
"It's early days because there are also reports of four birds flying around the crater on Rangitoto but we still haven't worked out the number because servicing the island is difficult and parakeets blend in with the background," Mr Catedral said.
Motutapu Restoration Trust chairwoman and former Auckland mayor Christine Fletcher said the sighting is the best Christmas present she could have hoped for.
The trust has planted nearly 500,000 trees on the island, by the trust at Home Bay, and Mrs Fletcher said Kakariki will provide the 1000 regular volunteers with a "beacon".
"It's only the beginning when you think of other species," Mrs Fletcher said.
She said the Kakariki's presence shows the importance of Motutapu for the environment and for tourism. The island is a 20 minute ferry ride from downtown Auckland.
Kakariki are island hoppers and can fly 60km with stops along the way.
Mr Catedral said parakeets are found on inhospitable sub-antarctic islands and the Kermadec Islands.
They can feed on grass, invertebrates and the flesh of animals, including washed up penguins.
Asked if they could one day populate Auckland, Mr Catedral said it is possible but rats and cats will hamper any breeding effort.
He said Kakariki sometimes nest on the ground making them easy prey predators.