The giants are back.
After an absence of more than 180 years one of the world's biggest insects is once again clambering through Northland tree tops.
More than 120 wētāpunga — the biggest of New Zealand's 11 species of giant wētā — were released last week in the Bay of Islands.
Once fully grown the females will weigh as much as a small bird and measure up to 20cm long, about the size of an adult hand.
Wētāpunga were once widespread in Northland but the gentle giants are highly vulnerable to introduced predators, especially rats, cats and mice.
They were wiped out on the mainland in the 1800s. Until 2012 the only wētapunga left on the planet were clinging to survival on Hauturu (Little Barrier Island).
Since then Auckland Zoo has worked out how to breed them in captivity and has returned thousands to pest-free islands in the Hauraki Gulf.
RETURN OF THE GIANTS
• New Zealand has more than 70 species of wētā, including 11 species of giant wetā, but the wētāpunga is the biggest of them all.
• Female wētāpunga can reach a weight of 35g, more than a sparrow. They can grow to 20cm long, including antennae.
• Wētāpunga were once common in Northland and Auckland but introduced pests wiped them out everywhere but Hauturu (Little Barrier Island). They were last recorded in Northland by missionary William Colenso in the 1830s.
• Wētāpunga are tree-dwelling herbivores that hide during the day and feed at night. They live for up to three years.
• Auckland Zoo has bred and released more than 4000 wētāpunga onto pest-free islands in the Hauraki Gulf. This week's release was the first outside the Auckland area.
&bull: They're big and scary looking but wētāpunga are gentle creatures. That big spike on the female's rear end isn't a stinger, it's a tube for laying eggs in the soil.
• Wētāpunga are even more ancient than tuatara. They've been around for 190 million years.
• So far 46 wētāpunga have been released on Urupukapuka Island, 42 on Moturua and 40 on Motuarohia, all in the eastern Bay of Islands. Thousands more could follow during the next three years.
• The islands have been pest-free since 2009 thanks to Project Island Song, an ecological restoration project. Tens of thousands of trees have been planted and species such as toutouwai (North Island robin), pateke (brown teal), tīeke (saddleback), pōpokotea (whitehead), kākariki (red-crowned parakeet) and Duvaucel's gecko have been reintroduced.
• Project Island Song is a partnership between community group Guardians of the Bay of Islands, Te Rāwhiti hapu Ngāti Kuta and Patukeha, and the Department of Conservation.
On Wednesday it was Northland's turn to welcome back these ancient creatures, whose 190-million-year lineage makes even the tuatara look with a newcomer.
The young wētāpunga, about 8 months old, were transported from Auckland in individual bamboo tubes by staff from Auckland Zoo.
After an early-morning welcome at Rāwhiti Marae they were taken by boat to the islands of Urupukapuka, Moturua and Motuarohia with about 40 released on each.
After a karakia volunteers tied the tubes to suitable branches and removed the mesh keeping the insects inside.
The wētāpunga were expected to wait until nightfall to emerge and seek out their favourite food, punga fronds.
The islands, part of an ecological restoration project called Project Island Song, have been pest-free since 2009 and are already home to many endangered birds and reptiles.
Project coordinator Richard Robbins said the release of wētāpunga, the first invertebrates to be reintroduced, was a major milestone.
''It's out of this world,'' he said.
''Because of the name Project Island Song people think it's all about birds but it's so much more. It's also invertebrates, it's reptiles, it's plants. This is a really special moment, having our first invertebrates. Hopefully we've got many more to come.''
The day did not go entirely to plan, however.
The releases were to have been done one after another but a delay on Urupukapuka plus the approach of wild weather mean the last two had to be done at the same time.
And at least one giant wētā tried to make an early break for freedom before it was spotted by Robbins.
''The best-laid plans don't always come together but it's all good. We achieved what we came to do, which was to release the 128 wētāpunga.''
He was optimistic the insects would thrive on the islands.
Another six or seven releases were planned over the next three years though the exact number would depend on how well the zoo's breeding programme went.
He expected the number of wētāpunga released would eventually add up to thousands.
Wednesday's release on Moturua was watched by about 40 people, including Project Island Song volunteers and descendants of the Clendon and Maioha families who lived on the island until the 1960s.
Kaumātua Matutaera Clendon, who grew up on Moturua, said he was ''really thrilled'' to witness the next stage in the island's restoration.
Giant wētā are an important but missing part of the New Zealand forest ecosystem. The only natural predator of adult wētāpunga is the ruru.