The first translocation of kōkako has taken place to predator-free Kāpiti Island for more than a quarter century.
Kōkako. Photo: RNZ / Jessie Chiang
This week 11 birds were moved from Pureora Forest to the island - the first of 35 scheduled to make the shift over the next two years.
Department of Conservation ranger for Kāpiti Lee Berry said it was hoped they would help to build up an "insurance population" of kōkako on the island.
"Which means if anything happens on the mainland, which it can do, we can restock from the birds here on Kāpiti which are really genetically diverse, really robust and a really strong population."
Berry said the new birds would top-up the existing 100 pairs on Kāpiti and add to the genetic diversity of the kōkako population there.
Kōkako were last reintroduce to Kāpiti in 1995 and it was always planned to continue that work.
Only 33 birds came across and just 11 bred successfully, meaning the existing population on the island lacks genetic diversity.
Berry said the new birds were captured at dawn in Pureora and accompanied by members of Ngāti Rereahu.
"Who brought them carefully and lovingly to our boat at Paraparaumu Beach and brought them over to one of the southern bays at Kāpiti.
"And 11 birds were released in a very moving ceremony in the forest with members of our local iwi Ngāti Toa, Te Ati Awa ki Whakarongotai and Ngāti Raukawa who were there to welcome them along with some our sponsors, the mayor and DOC rangers."
Berry said the kōkako would make a huge contribution to the population on Kāpiti.
"It is unfinished business for the genetic diversity of kōkako on Kāpiti which is really an insurance population for the mainland bird sites, so the idea with Kāpiti is that it's protected, it's safe, it's an island. The birds can't fly anywhere from here and if we can get a really good genetic mix of birds from a lot of locations in the North Island it will be a insurance population."
Berry said Kāpiti was still recovering from a fire which ravage the island about 200 years ago, but had enough habitat for the birds.
"We've got some fantastic stands of older growth forest and we've really got a kōkako strong hold in the centre of the island around the visitor area where we've got a couple of valleys of really good old forest.
"It's been regenerating in leaps and bounds since pests were eradicated, first of all possums and then rats in 1998, so the habitat is recovering and restoring itself. And we've now got almost the whole island, which is 2000 hectares, of suitable kōkako habitat."
She said the next step would be to relocate nine more birds from a different part of Pureora by the end of the year.
Although the national population of kōkako recently reached a milestone of 2000 pairs in the wild, predators remain a significant threat to kōkako.
DOC Technical Advisor and member of the Kōkako Recovery Group Tertia Thurley said the partnership enabling this translocation couldn't come at a better time.
"The kōkako on Kāpiti have been breeding well, especially over the past three to five years when numbers have nearly doubled. But with such a small number of founders, the population is not as robust as it could be.
"By adding bloodlines from key populations not already represented, we can build a really robust safe-haven for the species."
The translocation work was made possible through a partnership between DOC and Fonterra Brands New Zealand.
Tertia Thurley said the Recovery Group identified the top-up transfer to Kāpiti as one of the highest priorities for the species' national recovery, but the fast-breeding birds on the island would soon fill up available territories.
"The window of opportunity to add new birds was closing quickly. The partnership with Fonterra has enabled this crucial work to happen just in the nick of time."
Fonterra Brands managing director, Brett Henshaw, said the company was proud help support the population of kōkako on Kāpiti Island.
"We approached DOC wanting to support a significant conservation project in the Kāpiti region which recognises and appreciates the cultural and community significance of Kāpiti island," he said.