Kakī/black stilt adapting to life in Mackenzie Basin

Almost 150 of one of the world’s rarest bird species are adapting to life in Te Manahuna/the Mackenzie Basin.

This month 143 hardy kakī/black stilt have been released in the Godley River, and the Tasman River and include juveniles from an important female bird remaining in captivity named Māwhero.

She had several clutches of chicks with a new mate named Manunui, who she paired up with in a remarkable way, after tragically losing her first partner Wiremu.

Department of Conservation (DOC) Kakī Recovery Programme Wild lead Claudia Mischler said the bird’s wild adult population is up to about 156 adult birds (not including those just released), and was generally trending up over time, though it does fluctuate.

“They [kakī] have had a long journey since the 1980s when they were down to 23 adults – they’ve come a long way now,’’ Mischler said.

Raised in captivity, the critically endangered birds were released in time for Conservation Week, from August 14-20.

The annual week celebrated conservation work across the country and encouraged people to take action for the environment.

Mischler said staff will provide the newly released subadult kakī with supplementary feeding for the next few weeks to help them settle into their new environment while they learn to fend for themselves.

She said the breeding programme was successful and work continued to improve the birds’ survival rates in the wild.

Kakī were vulnerable to introduced predators and extensive trapping took place across the Mackenzie Basin, including through the Te Manahuna Aoraki Project and Project River Recovery programmes, with support from landowners.

“An action people can take to help kakī is to be aware and take care if fishing or otherwise out on riverbeds, as kakī or other birds may be around – especially over summer months when birds are nesting.

“If there’s a bird nearby, and it seems to be annoyed, move on and give them space.”

Te Rūnanga o Ngāi Tahu kakī species representative Rynee de Garnham had been at kakī releases over the past five years and said releasing the birds for their first flight in the open was always a special experience.

“Being able to see that, and watching the population increase, there’s nothing else like it,’’ de Garnham said.

She said it was important there were opportunities such as this for Ngāi Tahu whānau to engage and be better acquainted with the species, and to contribute to its success in the wild.

“My dream is for kakī to one day be found all across Aotearoa, and there will no longer be a need for the Kakī Recovery Programme.”

Captive rearing for wild release takes place at DOC’s Twizel facility and The Isaac Conservation and Wildlife Trust in Christchurch.

One significant bird held in captivity is Māwhero, who comes from a lineage underrepresented in the wild which means she was important for the genetic diversity of the species.

She was offered several suitors and originally partnered with a male called Wiremu. The pair had a very successful first breeding season but then Wiremu died suddenly due to cancer in February 2022, leaving Māwhero to raise the chicks on her own.

In November, a wild male kakī began hanging around DOC’s captive breeding aviaries in Twizel. He was particularly interested in Māwhero so staff opened the door and let the male in, and they soon formed a pair.

Looking back at the records, it was determined the male, named Manunui, was one of the birds originally trialled with Māwhero. Although they were friendly then, there did not seem to be any romance between them, so Manunui had been released into the wild in January.

The new couple were very successful this breeding season, raising several clutches of chicks, which means Māwhero’s valuable genetics were passed on and spread into the wild.