Pūtangatanga

Tree wētā are hard to misidentify. They are large, striped and adorned with brilliant spikes down their legs. Females and males are distinct too. Males have large dark coloured heads with big mandibles used to fight other males over mates. Females have smaller heads but a large spike emerging from the end of their abdomen. This curved spike is not a stinger, it is an ovipositor, an egg laying appendage.

They differ greatly in appearance with cave wētā as they are in distinct families. Cave wētā have much longer legs with smaller bean-shaped bodies.

Giant wētā are in the same family as tree wētā, but their shield-like thorax (middle body segment) is larger than their heads.

Ground wētā have small bodies and small legs and burrow underground.

Pūtangatanga are arboreal, but sometimes venture on the ground. During the day they hide in tree cavities, always head first with their spikey legs facing the entrance. At night they emerge from their holes to forage on plant matter, though they will opportunistically scavenge dead animals. Wētā have been recorded dispersing seeds from native plants, but they have to be small enough not to be destroyed by their mouth parts.

Males compete for mates, with large males defending a harem of females. Females lay their eggs in soil using their probing ovipositor. The eggs hatch in spring and out emerge mini wētā. Wētā go through several moults before reaching adulthood around 18 months after hatching. Pūtangatanga can live for three years.

There are several species distributed broadly across the motu. Some species have large ranges like the north island Hemideina thoracica and the central New Zealand/west coast Hemideina crassidens. Other species are more restricted like the West Coast bush wētā and the Banks Peninsula tree wētā. They are all forest dwellers except for the alpine stone wētā which lives in rocky crevices above the treeline.

The forest dwelling tree wētā species are generally not threatened. Tree wētā have survived on the mainland despite the extinction of their cousins the giant wētā, or wētā punga. Both groups are large bodied, flightless and nocturnal, much like many of our threatened birds. However tree wētā were adaptable to a life with mammals unlike the giant wētā. They are smaller in the presence of mammals like mice and rats, and are less active. Their ability to hide in tree hollows and aggressively defend them with their spikey legs has made them more resiliant. In areas where pests are entirely absent however, pūtangatanga grow larger, more numerous and more active.

There are two tree wētā species present at the Sanctuary. The most common, and often seen by visitors in our wētā hotels is the Wellington tree wētā, or Hemideina crassidens. Despite the name, this species is widely distributed from the lower North Island, through Marlborough, Nelson and the West Coast. The other species in the Sanctuary is only found on the higher altitude ridgeline. This is the Canterbury tree wētā, or Hemideina femorata. Pūtangatanga do incredibly well in the Sanctuary where pests are eliminated, however mice continue to have some impact. In our mouse exclosure we find a higher abundance of wētā, including some of monstruous size.

Pūtangatanga have ears on their legs! They communicate by stridulating, rubbing their spined legs across their body to create a sound.