Weta a Beautiful Thing

Big is beautiful right? Irresistible! It’s sort of like that bruise you get and while it hurts plain and simple you just can’t resist pressing it to REALLY know it hurts right? In the same way, the fascination I feel is more than I can resist when it comes to seeing them face to face. They seem frightening at first but in actuality, they’re just big old gentle giants.

Here in New Zealand we have some bold and beautiful creatures like giant wetas. Some of the more salient facts about wetas are that “they (Deinacrida, Hemideina) are one of the world’s most ancient species still living today. Fossil records from the Triassic period taken from Queensland, Australia show that it has changed little in 190 million years. More than 70 endemic species of weta have evolved in New Zealand with some reaching a gigantic size.

Tuatara, kiwi, saddleback and laughing owl are native predators of weta. Weta assumed the role in New Zealand’s original mammal-free native forests and shrublands that small rodents normally take in other ecosystems. Weta can be described as nocturnal grasshoppers, in fact the name Deinacrida means demon grasshopper. Like mice and rats they stay secluded during the day and emerge at night to eat vegetation, forest floor debris and sometimes sick or dead insects.

Unfortunately the weta’s ecological place has changed since Polynesians brought the kiore (Pacific rat) to New Zealand, and ship rats came with European settlement. The passive weta is now easy prey for the introduced rodents. The rat-sized giant weta reaches mammoth insect proportions, up to 6 inches in length. A gigantic record holding wetapunga (Deinacrida heteracantha) has weighed in at 71 grams (2.5 ounces) which is heavier than a thrush. It’s the heaviest insect in the world, but smaller in size than Titanus giganteus from French Guiana; goliath beetles of West Africa Goliathus goliatus and Goliathus regius; and the elephant beetles of South America Megasoma elephas and Megasoma actaeon.

The Gentle Giant of the Insect World
By all accounts he’s the gentle giant of the insect world. Really, he is. They get a bad rap because of their looks but hey I’ve seen some humankind that deserved the bad rap more! The male tusked weta looks all set for battle with its fearsome tusks (used to butt other males) and armour plating on its back. They appear even more scary when raising their long spiny back legs in defence.

Wetapunga
Maori in the Hauraki Gulf call giant weta ‘Wetapunga’ after the god of bad looks, and in the South Island they are known as ‘Taipo’ which means demon. Also known as ‘devils of the night’, they hardly live up to this bad name and are harmless to humans unless provoked because they are mainly herbivores. A weta is quite content sitting on people and will not bite or scratch if they do not feel threatened.

Any species surviving for such a very long time, outliving dinosaurs and making it through ice ages, has to be pretty tough. When naturalist Sir Walter Buller needed dead weta for his collection, he kept one under water for four days. Incredibly, it kept living, as did another that was dropped in near boiling water. For children reading, DO NOT do this at home! It is known that weta can survive in freezing climate conditions despite their lack of an antifreeze agent that other animals have to tolerate cold.

The smaller Stephens Island giant weta weighs 30 grams which is twice the weight of some mice. The Nelson alpine weta is the smallest at 7 grams. Until recently, there has been little scientific research on weta. The many different types of weta can be categorised as tree weta, ground weta, cave weta, and the spectacular tusked weta.

A strong physical characteristic is the extremely long antennae, which are normally twice the body length, however, the cave weta has antennae that are four times longer than its body. As far as insects go, weta have long lives, with 18 months to two years to adulthood, and then another six months to two years as an adult.

All of the three species of tusked weta are recent discoveries. The Middle Island tusked weta that is carnivorous and has been named “Jaws”, was found in 1970 by lizard expert Tony Whittaker in the Mercury Islands off the east coast of the Coromandel Peninsula. Another species was found in 1995 in the Raukumara Range on the East Coast of the North Island. Tusked weta are so named because the males have two tusks which they use to butt other males, or rasp together to warn off competitors.

A hundred Middle Island tusked weta raised by the Auckland Zoo and Landcare Research were released on rodent-free Red Mercury and Double Islands in 2000. These translocations will provide backup populations for the first tusked weta found on adjoining Middle Island.

At Risk
Sixteen of New Zealand’s wetas are at risk. Giant weta were once widespread throughout North Island lowlands. The Mahoenui giant weta was thought to be extinct on the mainland, until 1962 when a colony was rediscovered in an isolated King Country gorse patch. Department of Conservation biologists translocated 200 of them from the colony, south of Te Kuiti to Mahurangi Island off the Coromandel Coast, where they are breeding after four years.

In 2007, 100 rare Cook Strait giant weta Deinacrida rugosa were released into the wild at the Karori Wildlife Sanctuary in Wellington. It is the first translocation to re-establish the species since they became extinct on the mainland over a century ago. At about 70mm long, and weighing up to 27gm, the mouse-sized insects are among the world’s heaviest and most fearsome looking, however, they are much less ferocious than the smaller tree weta found in New Zealand homes and gardens.

The translocated weta were collected on Matiu (Somes Island) and released at two locations in the Karori sanctuary, where they will be protected from the rats and stoats that lead to their extinction everywhere, except a few offshore islands. Four transfers of 450 weta are planned over four years.”

Awe-inspiring
There is something very awe-inspiring about a creature that is millions of years old. I hope you agree, it would be lovely to have them around for a whole lot longer too. The best advice I can give you if creatures like wetas freak you out. Walk away. They’re not everyone’s cup of tea and mostly they get themselves in a whole lot of hot water just because of the way they look BUT sometimes under that big burly exterior beats a heart of pure innocence. Weta beautiful creature!