Dozens of giant wētā have been set free on Motuihe Island in Auckland's Hauraki Gulf as part of efforts to bolster the number of the rare and threatened creatures.
A breeding and conservation programme involving Auckland Zoo, DOC and local iwi has returned about 5000 of the prehistoric-looking insects to the pest free island since 2012.
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Auckland Zoo's ectotherms team leader Don McFarlane said 70 adult-sized wētāpunga were let go on Motuihe Island a few days ago and the colossal plant munchers play a vital role in keeping the forest healthy.
"In terms of specialness they're certainly endemic to New Zealand, found nowhere else on the planet," he told Checkpoint.
"The Department of Conservation considers them nowhere near doing as well as they should, so they've been listed as a species that needs action and help."
They are rightfully named 'giant', McFarlane said, as they are in the Guinness Book of Records for being one of the world's largest insects.
"These guys are in the record books at being 70 grams, which is getting on for the size of a saddleback… which is one of their main predators."
The release of the wētāpunga has been the realisation of a dream for McFarlane, and it is something he would like to see continue on islands around the Hauraki Gulf.
Breeding was not such a problem for the insects, he said, but rearing the young was where help was needed.
"They can produce many hundreds of nymphs or babies. We collect six from the 'founder' island Hauturu. So we can have in our wētā breeding room over 2000 individuals.
A wētāpunga - giant wētā - to be released on Motuihe. Photo: Auckland Zoo
"But to get them to six months - 2000 hungry mouths across the line so they're ready and strong for release - is a huge commitment, so we're talking three days a week, eight hours each day, and we have a specialist team which collects all the food they need, so it's quite a commitment.
"It's safe to assume they were [on the islands] before humans arrived, so they belong there," he said.
"They've been called forest regenerators, they've been called the mouse of New Zealand. They are like many other wētā species in New Zealand, they belong in the forest, they return nutrients to the soil through their gigantic poos, I think one of the largest poos for any insect.
"When they hit the ground from the trees I can tell you, you can hear it, certainly in our room with 2000 wētā, you can hear them all, almost pooing in synchrony.
"That's their contribution to the nutrient cycle on the forest floor, so that was missing before. The forest is only healthier with the addition of wētāpunga."
To some they may look creepy, but McFarlane says beauty is in the eye of the beholder.
A wētāpunga - giant wētā - to be released on Motuihe. Photo: Auckland Zoo
"Their whole life cycle is fascinating, and with fascination comes appreciation… They have a certain beauty in my eyes."
On the islands, workers track the wētā development with new tools including a unit that entices the insects with bait and captures photos of them, which are automatically uploaded.
"So we can remotely see what's visiting … and get an idea of whether they're there, what stage they are and, hopefully, numbers."