A seabird thought for more than a century to be extinct has been found breeding on an island in Auckland's Hauraki Gulf in what is being labelled an "internationally significant" find.
A team of researchers, led by Chris Gaskin and Dr. Matt Rayner from the University of Auckland, said they were "elated" to find the sparrow-sized New Zealand storm petrel - thought extinct since the 19th Century until being rediscovered in 2003 - breeding on Little Barrier Island Hauturu.
"It's an amazing result for our enthusiastic and dedicated team," he said.
The seabird is listed as critically endangered by the International Union of the Conservation of Nature and finding the breeding site was vital for conservation, researchers said.
In order to find the bird the team of researchers camped on the Poor Knights Islands, the Mokohinau Islands and Little Barrier Island, using radio receivers to zero in on the breeding site.
Gaskin said it was like "looking for a needle in the haystack".
A critical breakthrough came last year when the project team found incubation patches on birds caught at sea. This determined the timing of incubation and the best time to find breeding birds on land.
This year, 24 birds were caught at sea using specially designed net guns and small radio transmitters - weighing just one gram - fitted to each bird. Team members, based at a remote camp on Little Barrier Island, used handheld receivers and spotlights, to confirm that birds were coming ashore under the cover of darkness and moving inland.
When a signal was picked up of a bird stationary in forest at night, team members were able to get a clear fix on where that site was.
Rayner said the site being monitored was very fragile and with birds at a delicate stage in their breeding cycle.
"We are using automated equipment for the most part and maintaining a hands-off approach, although team members visiting the vicinity have also been keeping watch.
"On Friday morning a bird was discovered on the ground, possibly having just left its burrow. At the same time team members detected another bird, this one most probably on a nest," Gaskin said.
Members of the research team will remain on the island over the coming weeks. Aerial surveys are also being carried out to try and establish the distribution and size of the population.
Hauraki Gulf Forum chairman John Tregidga said locating the breeding ground was internationally significant and further highlighted the importance of the Hauraki Gulf Marine Park as a "globally significant biodiversity hotspot".
- © Fairfax NZ News
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