One of the world’s most remarkable insect recovery stories has been officially documented. The wetapunga, or Little Barrier giant weta, New Zealand’s heaviest insect, has staged a comeback after 15 years of captive breeding and translocation.

Tens of thousands of weta were bred at Butterfly Creek and Auckland Zoo, enabling 45 translocations of 11,000 weta to 10 new wild sites, according to a paper in the New Zealand Journal of Zoology. The species’ status improved from Threatened, Nationally Endangered in 2004 to Threatened, Nationally Increasing in 2022.

The programme began with just a handful of adults collected in 2008 and 2009, after field surveys showed too few juveniles in the wild to move directly.

“The journal paper summarizes one of the most comprehensive case studies of invertebrate conservation breeding ever undertaken,” said lead author Dr Chris Green of the Department of Conservation.

Why it matters: the weta, which can weigh as much as a mouse, is an ecosystem engineer, recycling forest canopy nutrients to the soil.