Waikato kākāpō reveal their escape strategies in new fence trial

The kākāpō trial at Sanctuary Mountain began just over a year ago. Photo / Jake Osborne

It has been a year since the Waikato made history as the first home for kākāpō on the mainland in 40 years.

The Department of Conservation (DoC) said it was a year of many learnings, including how the chunky and flightless parrots have continued to escape their fenced home at Sanctuary Mountain Maungatautari (SMM).

DoC operations manager for kākāpō Deidre Vercoe said DoC, Ngāi Tahu and the sanctuary had learnt a lot over the past 12 months about how kākāpō had taken to their new habitat and they continued to learn and adapt.

The first four kākāpō, Bunker, Māhutonga, Ōtepoti and Motupōhue, all 5-year-old males, moved to the fenced predator-free wildlife sanctuary between Te Awamutu and Putāruru on July 19, 2023.

On September 13, the quartet was joined by six more when males Elwin, 16, Kanawera, 8, Manawanui, 5, Tautahi, 5, Taeatanga, 10, and Manaaki, 5, moved in. They all came from predator-free islands off the South Island.

The sanctuary covers an area of 3400 hectares, separated into different enclosures and surrounded by 47 kilometres of predator-proof fence.

Department of Conservation kākāpō recovery operations manager Deidre Vercoe introduces Manawanui to the crowd at Sanctuary Mountain. Photo / Danielle Zollickhofer

Before the birds arrived, 38km of fencing had to be “kākāpō-proofed” with 400mm of thin stainless steel to stop the birds getting out – kākāpō can’t fly but they are known to be good climbers.

Despite the fence modification, Tautahi made headlines as the first kākāpō to escape SMM about a month after he moved in.

In November, DoC and SMM revealed another two birds had escaped.

It was suspected they used trees and bushes to boost themselves over the fence and onto neighbouring farmland.

DoC and SMM have since run climbing trials that have shown this initial theory to be correct.

Sanctuary Mountain Maungatautari general manager Helen Hughes said the team set up a pen replicating the perimeter fence, including the kākāpō barrier and overhanging vegetation.

“We essentially created a mini-sanctuary inside the big sanctuary to see how the birds use or don’t use the fence.”

Over five nights each, Tautahi, Ōtepoti and Bunker took turns in the pen while being observed by two team members and infra-red cameras.

“The trial confirmed the birds cannot climb the fence but use overhanging vegetation that moves with their body weight to get over it,” Vercoe said.

“We also saw that kākāpō have a good memory for previous escape options.”

Over the five nights, Tautahi and Ōtepoti made multiple escapes while Bunker showcased his climbing abilities but didn’t leave the pen.

SMM and DoC have a two-strike policy for the kākāpō: if a bird escapes twice, it is removed from the trial.

The first three birds were removed in November, followed by a further two in January and one in February.

Last month, the team decided to remove Ōtepoti from the trial too.

Hughes said that, with three escape attempts, Ōtepoti was a “good candidate” for the climbing trial.

“After reviewing the results from the trial, he was selected to go back down south.”

Sanctuary Mountain Maungatautari covers an area of 3400ha, with 47km of predator-proof fence. Photo / Danielle Zollickhofer

The kākāpō removed from the trial were all moved back to the offshore islands they came from.

There are now three kākāpō still in Waikato. They are Tautahi, Bunker and Taeatanga.

Bunker is the only one who hasn’t escaped the sanctuary – yet.

Former Waikato residents Elwin, Kanawera, Manawanui and Motupōhue continue to be trailblazers as they have been selected to start a new habitat trial on Coal Island Te Puka-Hereka in Fiordland in May.

Meanwhile, DoC and SMM are working on improved GPS tag technology to better monitor the birds.

“People think the birds have a GPS tracker and we can see where they are on our phones at all times. This is not the case,” Hughes said.

Tautahi is one of only three translocated birds still in the Waikato sanctuary. Photo / Jake Osborne

All three remaining kākāpō wear backpack-style GPS transmitters but the team has to use triangulation to find them – determining their position based on their distance from other points or objects with known locations. This is time-consuming and the accuracy can vary.

The system currently being trialled uses a range of different tags.

“The new technology sends signals more frequently, which makes the birds easier to locate because it’s more accurate,” Hughes said.

“We’re now getting new signals every five minutes. With the previous technology, we had new signals every 30 minutes.”

One of the tags was a remote-download GPS tag, which has already shown promise.

DoC is now working on a version with a bigger battery for longer-term use.

DoC said all three remaining birds were still frequently found near the fence line.

“One new theory for this is that the easy travel and interesting food sources, such as blackberry and grass seed, around the perimeter could be why they enjoy living on the edge,” a statement from a DoC newsletter said.

“If so, it could be that they are unintentionally ending up on the other side, rather than any drive to get out.”

As a short-term measure, the team started a supplementary feeding regime to encourage the birds to move inland.

Taeatanga, who recently turned 10, was the first to be enticed and it appears he settled into a new range a safe distance from the fence.

Overall, Hughes said she was very pleased with the trial.

“The trial has delivered far, far more than we anticipated,” she said.

Māhutonga and Motupōhue were part of the first cohort of four kākāpō that moved to Sanctuary Mountain Maungatautari. Photo / Danielle Zollickhofer

“It’s been an amazing year, but we’re still in the early days. It’s been very busy, exciting, challenging, but also informative.

“Our hope is that this information can be used to grow the number of birds at Sanctuary Mountain Maungatautari.”

However, there were currently no plans to increase the number of kākāpō in Waikato.

Hughes said she wasn’t worried about having the number of birds reduced from 10 to three.

“At the end of the day, it’s still a trial. Ultimately, our approach is about what’s right for the birds.”

Waikato kākāpō trial timeline

• July 2023: Bunker, Māhutonga, Ōtepoti and Motupōhue move to Waikato
• September 2023: Elwin, Kanawera, Manawanui, Tautahi, Taeatanga, and Manaaki join the quartet
• October 2023: Tautahi is the first bird to escape the sanctuary
• November 2023: Tautahi escapes a second time, Motupōhue and two other birds breach the fence and the decision is made to relocate Motupōhue, Manawanui and Kanawera to a southern predator-free island
• January 2024: Elwin escapes twice, Manaaki and Elwin are removed from the trial
• February 2024: Māhutonga returns to his original island home after breaching the fence twice in a short period
• May 2024: Former Waikato residents Elwin, Kanawera, Manawanui and Motupōhue move to Coal Island Te Puka-Hereka and the DoC and SMM team starts trialling new GPS tags
• June 2024: Ōtepoti is removed from SMM and moves back down south

What are kākāpō?

Kākāpō are nocturnal and flightless parrots native to New Zealand.

They evolved without the presence of mammals: in the 1860s, Fiordland surveyor Charlie Douglas described the birds as being so populous “you could shake a tree and the kākāpō would fall down like apples”.

As the birds evolved, they gained weight and lost their ability to fly, making them vulnerable to introduced cats and stoats.

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.

Since 2016, the population has doubled to reach a high of 252 birds in 2022 and their island homes are almost at capacity.

The current kākāpō population is 247.

Kākāpō chick Heather One. Photo / Brett Phibbs

The birds can climb well and walk several kilometres at a time. When they’re disturbed, kākāpō freeze and camouflage.

They are notoriously slow breeders, with females laying between one and four eggs every 2 to 4 years. The next breeding season is predicted to be in 2026.

Kākāpō are the heaviest parrot species in the world: females weigh around 1.4 kg and males 2.2 kg. Before a breeding season, they can pile on 1kg of fat.

They are herbivorous, meaning they eat only plants, and they have an estimated life expectancy of 90 years.

Until the habitat trials in Waikato and Coal Island, kākāpō were present on only four offshore islands: Anchor Island/Pukenui and Chalky Island/Te Kākahu o Tamatea in Fiordland, and Whenua Hou/Codfish Island and Pearl Island near Rakiura/Stewart Island.

The famous "mating" incident during filming of a Stephen Fry BBC TV series in 2009.

Each kākāpō has its own personality and they are usually solitary creatures, although females and young birds are occasionally found together in small groups of two to four.

In 2008 and 2020, the kākāpō was crowned bird of the year.

The species rose to fame internationally after New Zealand’s official spokesbird for conservation, Sirocco, had a special encounter with zoologist Mark Carwardine.

Carwardine was filming the BBC documentary Last Chance to See with British actor Stephen Fry and footage showed a rather frisky Sirocco attempting to mate with Carwardine’s head.

Danielle Zollickhofer is a multimedia journalist and assistant news director at the Waikato Herald. She joined NZME in 2021 and is based in Hamilton.

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