Auckland Tree Weta
The Auckland tree weta is a relatively large member of the cricket family. They are an insect and as such have six legs. The back pair of legs is covered with large spikes that are used for defense. Some individuals have small wings but these are incapable of allowing them to take flight.
Males and females differ slightly in their appearance. The males head is almost twice as long as the females and they have larger mouthparts which are used to defend their harem of females against attack by rival males. The female has a large ovipositor on the rear which is used to deposit their eggs.
Protruding from the top of their head are a pair of antenna.
Their head is a dark brown or black colour with the body ranging in colour from white to brown and patterned with black spots or stripes.
Adults measure up to 40mm (1.6in) and weigh 3-7g (0.1-0.25oz).
The tree weta is an omnivore. They feed on a range of leaves, fruit, seeds and insects. Those living at a higher elevation will feed on more insects.
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The Auckland tree weta is native to New Zealand. Here they can be found across much of the Northern portion of the North Island including around their namesake city of Auckland.
Auckland tree weta are found in forests and scrub.
As their name suggests they live in trees inside a burrow known as a gallery. This has often been bored out by beetle larvae or through rot originally. Once they move in the tree weta will use their strong mandible to help shape out the tunnels in to their home and to chew away bark growth around the tunnel opening.
They are also able to survive in suburban backyards. In some parks in New Zealand groups will build a weta hotel which they use as their habitat.
The female Auckland tree weta is able to lay eggs almost year round though a break is observed in Winter.
Both the male and female will mate with multiple partners throughout a breeding season. Eggs typically hatch in Spring.
Their eggs are laid in the soil or rotting wood. Once these hatch they are provided no care by the parents. Females may lay up to 300 eggs throughout their life.
At birth a young Auckland tree weta resembles a smaller version of the adult. Throughout their development they will shed their exoskeleton and then grow slightly. It will take 8 instars (the space between sheds) for them to reach their adult size.
Young weta take 2 years to reach adult size and are able to begin breeding soon after.
Auckland tree wetas live in their galleries with a group of others. This group is typically made up of a single male and up to 10 females or young.
They can produce a hissing sound by rubbing the legs against their abdomen.
This species is nocturnal and during the day they will reside in a tree hollow.
Predators and Threats
Since the establishment of mice and rats in New Zealand they have been outcompeting the Auckland tree weta for food.
When threatened the Auckland tree weta will hiss or bite. They will also flick their back legs which are spiked at predators.
The ear of the weta is found just under their knee.
Weta have been around for over 190 million years.
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James O’Hanlon / CC BY (https://creativecommons.org/licenses/by/4.0)
Ambrose, J., 2015. Wildlife Of The World. 1st ed. London: Dorling Kindersley,
Gibbs, G, 1994, THE DEMON GRASSHOPPERS, New Zealand Geographic, Available at https://www.nzgeo.com/stories/the-demon grasshoppers/#:~:text=For%20an%20insect%2C%20a%20weta,live%20longer%20than%20giant%20weta.Science Learning Hub. 2020.
Wētā. [online] Available at: <https://www.sciencelearn.org.nz/resources/1962-weta> [Accessed 10 June
Wetageta.massey.ac.nz. 2020. Tree Weta. [online] Available at: <http://wetageta.massey.ac.nz/Text%20files/treeweta.html> [Accessed 10 June 2020].
iNaturalist NZ. 2020. Auckland Tree Weta (Hemideina Thoracica). [online] Available at: <https://inaturalist.nz/taxa/85221-Hemideina-thoracica> [Accessed 10 June 2020].