North Island kōkako disappeared from Waikato’s Mount Pirongia in the 90s. A vision by the Pirongia Te Aroaro O Kahu Restoration Society to bring them back is being realised as this season’s fledglings take their first leap of faith.
By Carisse Enderwick, Community Ranger, Waikato
What’s it like to stand inside an ancient forest, to be held in the still embrace of a maunga on a crisp early morning, sensing the movement of life all around you?
To hear, see and feel the trees, the plants, the hum of insects waking up, the music of a thousand resident birds greeting the dawn.
What’s it like to hear a birdsong so beautiful your soul responds to it like an old friend?
We’re in a time where we need to fight to answer those questions.
Waikato’s Pirongia Forest Park is a natural home for North Island kōkako (Callaeas wilsoni), an endemic, blue-wattled bird with a charismatic black mask. It’s been said to sing the most beautiful bird song in the world (there’s probably some competition for the title, of course).
Kōkako disappeared from the maunga in the 1990s because their population couldn’t cope with the impact of rats, possums, and mustelids (stoats, weasels and ferrets). The birds can only survive in native forests with areas that are actively managed to reduce these pests. Under relentless attack through egg predation, overgrazing of food supplies, and the killing of chicks, kōkako stood (and stand) little or no chance without pest management interventions.
In 2002 the Pirongia Te Aroaro O Kahu Restoration Society was formed.
Its founding members had a vision: to return the world’s most beautiful bird song back to the maunga. It was an ambitious dream. It began with pest control over just 250 ha of forest which eventually grew to 1030ha, and then a further 1000ha at Pureora was taken on in 2016 to benefit kōkako directly living there. By 2017 the first 20 birds, hailing from Pureora Forest Park, were brought back to the maunga. In 2018 a further 14 birds were translocated from Tiritiri Matangi Island in the Hauraki Gulf, followed by another 10 from Pureora, and by April 2020 these avian pioneers had fledged 18 chicks. The 2021 breeding season has just ended and there’s hope for another 20 fledglings.
Fledging birds is no easy feat. There is a process, and it requires patience, skill, dedication, and a lot of teamwork. It begins at the courtship stage. Dave Bryden and Amanda Rogers are ecologists who work with kōkako closely and have been collaborating with the Society to return the birds to the maunga. Dave and Amanda go into the predator-controlled area and locate pairs early in the season (around September/October).
The birds are known for their secrecy, often heard, not seen, and so locating them is not an easy task.
“We listen for kōkako calls and wingbeats, and use playback if we need to,” says Amanda. “If a kōkako is defending a territory, it will come out from its treetop hideouts to investigate the song.”
A territory range can be 4-25 hectares, depending on food sources and the pressure for space from adjacent pairs.
“Once a pair has been identified, it becomes a waiting game,” Amanda says.
Dave and Amanda watch from the ground for any signs of nesting: birds carrying sticks, moss or fluffy fern scales; males feeding females beak-to-beak; or a female disappearing into a tree for a long time.
“Dave and Amanda are really sharp at trying to work out by indirect means where the birds are and what’s going on in the nest,” says Clare St Pierre, Chairperson of the Society.
“The more they watch, the more they can confirm the birds are there. It’s a process that can’t be rushed and it takes a lot of skill and patience.”
When a nest is found it’s monitored twice a week by volunteers who will go up and spend an hour watching it.
“If a female is incubating or brooding, the male will usually feed her on the nest,” says Amanda.
“If there are chicks, we gauge the age of the chicks by the time a female spends on the nest, and how frequently one or both parents bring food. As the chicks develop feathers, mum can be off the nest for longer periods of time, and as the chicks grow, both parents become focused on frantic food-gathering.”
Because each nest is so precious, and every female incubating is an easy target for predators, the Society leaves nothing to chance. Beneath the nest at the base of the tree, 20 rat traps and one to two possum traps are set, known as a “ring of steel”. Volunteers check these traps every four days, resetting and adding more bait where necessary.
“Rats and possums have been caught,” says Clare “…so it’s worth doing. It is necessary.”
This season seven pairs were identified in the predator-control area; one in the Kaniwhaniwha catchment; and one next to the Sainsbury mountain bike park. This year nearly all the nests have been close to walking tracks, so they’ve been easier to get to.
And finally when all the nest-watching hours, days, weeks have been clocked, the day comes when the birds are ready to fledge. Clare lights up.
“Their parents will make tiny, sustained contact calls from a neighbouring tree, encouraging the chicks to leave the nest. The youngsters run up and down the branches, daring themselves a little further away from the nest each time,” she says .
At some point in our lives we’re all called to take a leap of faith, to trust we’ve been given everything we need to make the jump and, with some hope and luck, the universe catches us. Mostly.
“But there are times when a fledgling ends up on the ground,” says Clare “So they may spend a day or two close to the ground to regain confidence before trying again.”
And isn’t it just a beautiful metaphor for life?
Once a young bird has left the nest, it’s considered fully fledged. When a nest is successful there’s a personal sense of accomplishment, yes, but it’s more than that.
“We couldn’t have this success without our volunteers and support from DOC and iwi,” says Clare. “It wouldn’t work with even just a few of us. There are trappers, volunteers, ecologists – it’s a massive, coordinated group effort. And we all love it because we know together we’re making a difference to kōkako.”
When asked what keeps her personally motivated to keep going, Clare becomes serious and reflects.
“These birds used to be so widespread before colonisation. The people who came here and cleared the forests probably didn’t know what they were doing. But now, how could we as a society be part of wiping out the most beautiful song in the world? I don’t want to be a part of that. I want to be a part of bringing it back.”

📷: photo Carisse Enderwick
And so at the close of the nesting season, there are 23 fledglings. It’s a celebration because none of this is easy or certain or comfortable, and those that do the work never expected it to be, nor do they expect it will be.
But our soul’s calling will likely lead us to places of difficulty, uncertainty, uncomfortableness; to places where we’re invited to jump in with both feet trusting that this is what we’re meant to be doing. The uncomfortableness of it all is something we learn to lean into, because it’s in that space the good stuff happens: the growth, the miraculous, the prevailing.
Folks like the Pirongia Te Aroaro O Kahu Restoration Society show us that when we jump together (especially into the hard stuff) beautiful things happen. Forests come back to life, songs get sung, and new life itself is given a chance to leap and then, with sustained group effort, soar.
Read more about this work: https://www.doc.govt.nz/news/media-releases/2021-media-releases/pirongia-kokako-fledglings-taking-the-leap/