Some Australian migrants have made a small contribution to reversing the flow of traffic across the Tasman.
Thirteen Pelicans have made New Zealand their home, settling on the banks of the Northern Wairoa River, known as the Big Muddy, near Dargaville. The flock is exciting birdwatchers and locals, who would normally be able to see pelicans only in a zoo.
Experts believe the rare visitors could start breeding here and make the Northland river their permanent home.
"Nothing is impossible," said a Massey University zoology lecturer, Dr Phil Battley, who believes the birds made their way here on an "unhelpful wind".
Dr Battley said the birds would need an adequate food supply for several months, and undisturbed sandbanks to nest on.
He said there were at least four cases of the Australian pelican species drifting over to New Zealand before, one involving three birds, but the flock of 13 in Kaipara was thought to be a record.
Professor Richard Kingsford, a University of New South Wales expert on pelicans, also believes the birds could make New Zealand their permanent home, "if there is sufficient food supply".
The Northern Wairoa river is known to have a rich supply of mullet which is thought to be a favourite food of the pelicans, he said.
The managing director of Kaipara Water Transport, Wayne Eyles, spotted the visitors as he cruised along the river more than a week ago and has seen them every day since.
"I couldn't believe it when I saw them at first. I've been on the ocean nearly all my life in New Zealand and I've never seen a pelican before."
Mr Eyles said the birds were in two groups, six at the Ruawai site and seven spotted at the Aratapu bank.By Rose Stirling