The giant Weta is another native animal unique to New Zealand. There are around 100 species in the country, 16 of which are endangered. It is an amazing looking creature – an invertebrate with a large body, spiny legs and curved tusks. The giant weta has remained virtually unchanged from190 million years ago. Having outlived the dinosaurs, they are sometimes known as the dinosaurs of the insect world. The 100 species are divided into 5 groups – giant, tree, cave, tusked, and ground. The most endangred species of weta is the Middle Island Tusked Weta (Motuweta isolata) but all three species of tusked weta are protected.
The weta can grow up to an incredible 82 mm – incredible that is for a creepy crawly insect. They will only bite when threatened but can look very aggressive, and will throw their hind legs into the air when they perceive they are in danger. The creature’s Maori name is Wetapunga, and is known as “the god of the ugly things” by the Maori.
Wetas are nocturnal and are often found in trees, under rocks, rotting logs, in trees and under plants. They often seek cover in these natural hiding places to avoid detection during the day. They too have been victim to natural predators, as they move very slowly and cannot jump due to their weight. Thus introduced predators such as stoats, rats, ferrets cats and hedgehog have preyed on them and reduced their numbers. The weta’s habitat (including shrub land, caves, forests, grassland) has also been destroyed by human behaviour – clearing land, for example for agriculture. Wetas are mainly herbivorous, but there is some evidence that they sometimes eat other insects.
The life span of a weta is a mere two years, an especially short time since they only mature at the age of eighteen months. At this age the male will select a female and they will stay together for six months before the female lays 100 to 300 eggs. The weta eggs will hatch 3 to 5 months later, but the parents will have died by then.
Though many are endangered, there has been a concerted and successful recovery effort. Wetas are mostly adaptable to a changed habitat and as a result captive breeding programmes have been very successful. Invertebrates such as the weta also need much less space for survival than other animals, and therefore can adapt to a smaller habitat than originally.