For the first time in more than a century, kākāpō have been heard booming on the North Island of mainland Aotearoa New Zealand.
Iwi Ngai Tahu revealed today that at least two of Sanctuary Mountain Maungatautari’s three resident kākāpō have completed their first season of booming.
Booming is one aspect of the elaborate breeding behaviour of male kākāpō, designed to attract the attention of potential mates.
It is a very low-frequency sound, almost like a heartbeat, with a quieter boom and a stronger one.
Taeatanga, 11, started booming in December and 6-year-old Tautahi followed suit. It’s unknown if Bunker, the third and youngest male at the site, boomed this year.
There are currently no female kākāpō at Sanctuary Mountain Maungatautari.
Department of Conservation Kākāpō Recovery Programme operations manager Deidre Vercoe said returning the booming sound to mainland Aotearoa after decades of kākāpō existing only on offshore islands was very special.
However, there was still a lot of work to be done.
“It’s still too early to know whether [Sanctuary Mountain Maungatautari] could one day support a breeding population.
“These males have been supplementary fed over the last six months to help with the challenges of keeping them settled inside the fenceline.
“It is likely this has helped them reach booming condition, so we don’t know if they would boom on the maunga without this feeding.
“Males have also been known to boom without the presence of females before, at island sites that didn’t support a breeding population. It will be many years before we know enough about this site and its future for kākāpō.”
Te Rūnanga o Ngāi Tahu representative on the Kākāpō Recovery Group Tāne Davis said hearing the endangered bird boom at the Waikato sanctuary was a significant milestone.
“While males booming does not necessarily mean that the maunga will be a successful breeding site in future, it is a clear sign that the manu are feeling at home and comfortable to exhibit their natural behaviours,” he said.
Ngāti Korokī Kahukura representative and Sanctuary Mountain Maungatautari cultural advocate and educator, Bodie Taylor said hearing the booming of kākāpō back on Maungatautari was a privilege.
“[It’s] a testament to the importance and success of our relationship with Ngāi Tahu. We are looking forward to the next steps in this journey to hopefully welcoming female kākāpō to Maungatautari one day, and the opportunity of being able to contribute to the population growth of these precious manu,” Taylor said.
Sanctuary Mountain Maungatautari chief executive Helen Hughes said the booming was to be truly celebrated.
“It has been a wonderful, and at times challenging, 18 months of learning, both for the birds and for everyone involved in this ground-breaking recovery effort... The booming is an extremely positive sign for the future of kākāpō at Sanctuary Mountain Maungatautari,” she said.
Before sending out their booming call, kākāpō males find a prominent spot to form a bowl in the ground. Settled in this bowl they inflate air sacks in their chest which creates the boom sound.
The males would emit a low-frequency boom every 1 to two seconds, which can be heard a few hundred metres away on flat ground, or up to 5km away in the mountains.
After 20–30 booms they make a high-pitched “ching” sound which helps any interested females to locate them.
The booming and chinging serenade can last for up to eight hours without any break.
Those hoping to hear the birds boom during a visit to the sanctuary are expected to be out of luck, as the birds have likely finished booming for the season.
The Sanctuary Mountain Maungatautari kākāpō trial began in July 2023 when the first cohort of four birds moved to the Waikato site. In September 2023, the trio was joined by a sextett.
Since the birds arrived at Sanctuary Mountain Maungatautari, they have kept rangers on their toes with numerous escapes.
As a result, the number of birds has been progressively reduced. The last bird to leave the Waikato site was Ōtepoti who left in June last year. He passed away due to unknown causes in September after being found underweight and unwell.
Kākāpō are nocturnal and flightless parrots native to New Zealand.
Today, kākāpō are critically endangered and have been recovering from a population as low as 51 birds in 1995. At one point they were believed to be extinct. The current population is 243.
They ususally live at predator-free offshore islands in the South Island.
The trial is run by DoC’s Kākāpō Recovery Programme, with support from its National Partner Meridian Energy, together with Treaty Partner Te Rūnanga o Ngāi Tahu, Sanctuary Mountain Maungatautari, Ngāti Koroki Kahukura, Ngāti Hauā, Raukawa and Waikato.