Return of the giants: More giant wētā released in the Bay of Islands

Reporter·Northern Advocate·

20 Jun, 2023 05:00 PM3 mins to read

The wētāpunga, one of 11 species of giant wētā, is the world’s second-biggest (but heaviest) insect. This one isn’t even an adult. Photo / Darren Markin

The chances of survival of a massive insect barely changed in 190 million years have been boosted by another release of giant wētā in the Bay of Islands.

Last week’s release of wētāpunga — the biggest of all 11 species of giant wētā — was the third carried out by Project Island Song, a community initiative to restore the native flora and fauna of the Ipipiri islands between Russell and Cape Brett.

The 164 near-adult wētāpunga were split between Motuarohia, Moturua and Urupukapuka islands, project general manager Richard Robbins said.

The biggest weighed more than 30g but adult females could tip the scales at 70g, as much as a small bird.

The group had now released 365 wētāpunga across the three pest-free islands, all of them bred at Auckland Zoo from insects captured on Te Hauturu-o-Toi/Little Barrier Island.

The Bay of Islands had the world’s only wild population of prehistoric creatures outside the Hauraki Gulf.

Robbins said the wētāpunga were separated into age cohorts, between 14 months and two years old, before being taken to the release sites in the hope they would reach breeding age around the same time.

He was also hopeful the new arrivals would breed with wētāpunga already on the islands, descended from the first insects released into the treetops in 2020 and 2021, to boost the population’s genetic diversity.

Wētāpunga lived on average for three years but only started breeding in their final year of life, he said.

The wētāpunga from the first release were now nearing the end of their lives but their offspring had been detected on previous visits.

Ben Goodwin, a senior keeper in Auckland Zoo’s ectotherm team, shows the kids a wētāpunga. Photo / Darren Markin

Giant wētā played a vital role in the ecosystem before they were all but wiped out by introduced pests, Robbins said.

They ate leaves and fern fronds and produced droppings that recycled nutrients from the treetops to the forest floor.

That was especially important in New Zealand, which had few deciduous trees and hence no leaf cycle to ensure nutrients were returned to the soil.

They were also fascinating creatures, he said.

“They’ve hardly changed in 190 million years and they’re the second-largest insect species in the world. They’re reasonably placid for a wētā, they’re pretty chilled out, and I think they are quite stunning.”

The giant wētā are accompanied deep into the island’s forest by Auckland Zoo staff, Project Island Song volunteers and curious visitors. Photo / Darren Markin

More than 100 people took part in the June 14 release. They included members of Ngāti Manuhiri, who are the mana whenua of Te Hauturu-o-Toi/Little Barrier, and a film crew working on a TV series about Auckland Zoo’s conservation work.

Bay of Islands hapū Patukeha and Ngāti Kuta welcomed the wētāpunga at Rawhiti Marae before they were transported to the islands in Project Island Song’s newly acquired boat.

Robbins said he was grateful to sponsors and grant organisations, and especially the partnership with Auckland Zoo, that made the reintroduction of giant wētā possible.

Next on Project Island Song’s reintroduction wishlist was the Northland green gecko, which Robbins hoped would be scampering through the islands’ undergrowth in 2024, and the tītīpounamu or rifleman, New Zealand’s smallest bird, which could be released at the earliest in 2025.