Orthopterans are one of the most diverse orders of insects globally, with more than 20,000 described species. 

In Aotearoa New Zealand, there are about 162 species of orthopterans listed nationally in 2022 as part of the New Zealand Threat Classification System (NZTCS). 

All our wētā in Aotearoa New Zealand are endemic, meaning they only occur naturally here and nowhere else in the world. They are quite large compared to other insects, with some weighing more than a sparrow. There are wētā that hiss, bite and wave their spiky legs when threatened, while others leap up to 3 metres. And then there are the wētā with curved tusks designed for combat. 

Despite their fearsome looks, wētā are elusive creatures being more threatened than threatening – and they need our protection. 

Wētā are important ecologically. Most species are omnivorous – they consume vegetation and small invertebrates.  

The main threat to all our endangered Orthoptera is predation by introduced mammals, followed by habitat loss.  

All species of giant wētā are currently confined to predator-free islands or to high alpine regions because they cannot coexist with mammalian predators, including rats, mice, hedgehogs, cats and mustelids (stoats, weasels, ferrets). All species of ground wētā and of cave wētā found in Otago are also suppressed to lower numbers than they would naturally be found in because of mammalian predation.  

Wētā also compete with introduced species like mice and rats, which occupy a similar niche. Introduced species tend to disrupt ecological food webs – for example, mice may eat the same things as wētā – but they do not provide food for native species like kiwi or tuatara. 

In Otago, the total number of wētā, cave wētā, crickets, grasshoppers identified is 42 species. Of these, 39 species were listed nationally in 2022 as part of the NZTCS. The remaining three species have been described since the assessment for the NZTCS.

The number of wētā, cave wētā, crickets, grasshoppers that are regional endemic to Otago is six. Being a regionally endemic species means they naturally occur only in a region.