New Zealand's giant wētāpunga rebounds after massive breeding and release effort

The wētāpunga, a cricket-like insect weighing up to 35 g and once restricted to Little Barrier Island, has made a strong comeback thanks to a novel breeding scheme led by Butterfly Creek and Auckland Zoo. Scientists fed the nymphs a mix of fresh leaves, fish flakes and leaf litter, raising them in large communal cages until they could survive on their own. Beginning in 2010, more than 11,000 individuals have been translocated to predator-free islands and two mainland fenced reserves, establishing multi-generational populations.

Recent surveys recorded an average of 28.5 insects per person-hour of searching, far exceeding the 1.4 recorded on the original island. The Department of Conservation’s assessment in 2022 downgraded the species from “Endangered” to “Threatened - Nationally Increasing.” Researchers hope the techniques can be applied to other at-risk invertebrates such as the Canterbury knobbled weevil and native stag beetles.