One of Northland's largest tracts of native forest will soon echo to the haunting call of the kokako.
Three of the endangered birds were released in Puketi Forest, which straddles the hills between the Bay of Islands and the Hokianga, on Friday and should be followed by seven more in coming weeks.
The release is a major milestone in the efforts of the Puketi Forest Trust, which is working to restore the forest and re-introduce locally extinct birds. Since 2003 the volunteers have been trapping pests in 5500ha of the 15,000ha forest.
The first species to be re-introduced, and now breeding successfully, was the toutouwai (North Island robin) in 2009.
Unlike the toutouwai, which vanished from Puketi a century ago, the loss of the kokako was recent and dramatic.
From a population of 120 in 1986 the population plummeted to just seven males in 2003, one of the sharpest declines ever seen in a native species.
Trustee Gary Bramley, of Kaeo, said the first three birds were caught at Mataraua Forest, near Waipoua, at 6.30am on Friday and taken by helicopter to Puketi Forest, where they were released at 11am. A team of eight experts remain at Mataraua hoping to catch five pairs in total.
''It's a big milestone for the project. It's been a long time coming,'' Mr Bramley said.
Mataraua is home to the only viable population of kokako left in Northland; a census in 2010 showed numbers were high enough to allow a transfer to Puketi. The trust has permission to move 10 birds this year and 10 more in 2013.
Mr Bramley said the trust was trying to transfer pairs in the hope they would stay together and breed. The birds had been fitted with radio transmitters so they could be tracked.
Recorded kokako calls were being played to persuade the birds to stay in the core pest-trapping area. If the birds moved the volunteers would have to follow them by expanding the trapping area. Rats and possums are their main threat.
The kokako project is led by the Trust with help from the Department of Conservation, Te Roroa of Waipoua, and Piki Te Aroha Marae.
The kokako has grey feathers, a black mask around its eyes and bright blue wattles below its beak. About 1400 survive in the North Island; a South Island subspecies is thought to be extinct.
The number clinging on at Puketi before the release is not known but could be as low as two. Two Puketi kokako are being bred at Hamilton zoo and two more are on pest-free Lady Alice Island in Bream Bay. They will also be brought home to Puketi.
Go to www.puketi.org.nz to find out more.