New Zealand Insects You Won’t Forget in a Hurry
by Helen Cordery
It’s happened to the best of us. You’re walking along the forest floor listening out for the heavy flap of a kererū’s wings when all of a sudden you notice something in your hair. Or maybe you’re busy peering at a gorgeous rimu trunk when you realise that what you thought was lichen was actually the camouflaged hide of some kind of creepy crawly.
We would forgive you if you let out a little scream (we’ve all done it) but it’s time to turn that shriek of despair into one of excitement.
Some All of the bugs we have here at Pūkaha are amazing, part of the tangled web we call the ecosystem, and without them, the world would be a very different place. So let’s take a moment to wonder at a few of our favourite New Zealand insects and discover the fascinating role they play in this game called life.
Even though it’s called a weevil, its name is deceptive – it is not a weevil. Instead, it is an endemic beetle of the Brentidae family. They are also sexually dysmorphic, which means that males and females look different from each other. The male grows to about 85mm and has a huge, elongated head (rostrum) which they use for fighting with other males. The females, on the other hand, grows to about 45mm and have a much smaller rostrum which is used to bore holes in the ground for their eggs (between October and March). Once hatched, the larvae then spend a good two years living inside the tree before exiting as fully-grown huhu beetles.
Take a good look if you come across them at Pūkaha – if you peer closely you may see hundreds of tiny mites on their bodies. Four different types of mites have been found hitching a ride on the giraffe weevil but the reason why is still not known.
The Huhu beetle is a much-loved treat of our tuatara and is also the largest beetle in New Zealand. They are also known as ‘haircutters’ because they have the unfortunate reputation of getting tangled in hair and having to be cut out thanks to the tiny hooks that line their tiny legs.
The beetles start off as the infamous huhu grub, a white larva that grow to 70mm long and lives in trees or in rotting wood. They especially prefer damp wood, which they eat at a frenetic pace resulting in long tunnels that are loved by other creatures as well as fungi and important bacteria that work to decompose waste.
The beetles leave the tree after about 25 days, particularly during December and January. They enjoy the dusk, but have to be careful of ruru (morepork), magpies and kiwi who all love them! Traditionally, huhu grubs were enjoyed by Māori (they are especially tasty fried or roasted) and were also used as bait when fishing for tuna (eel).
While these insects get pretty long, they can be really tricky to spot in the forest. That’s because they are masters of disguise, looking just like branches, logs or even leaves. They are most active at night which is why so little about them is known, a surprising fact considering stick insects can be found all across Aotearoa New Zealand.
Did you know they are related to wētā and grasshoppers? There are 21 species of stick insect in the Phasmatodea order and they also have some rather peculiar habits that are little understood. For example, females can reproduce without males (parthenogenesis) and they also ‘dance’ for hours on end, swaying on branches for a reason scientists have yet to comprehend. If you find a stick insect, it may even appear dead but don’t be fooled – this is one of their greatest defence mechanisms and they have been known to act lifeless for hours.
The wētā is probably New Zealand’s most famous insect, known for its large size and unusual habits. While the wētā has relatives that can be traced all over the world, our iconic wētā is endemic and unique. Although you can find cave wētā at Pūkaha (keep your eyes peeled near our glow worm cave on a Night Tour), the tree wētā is the most common, being found in New Zealand gardens nation-wide. As you walk around Pūkaha, take a look in the ‘wētā hotels’ which you can find dotted around the Reserve as well as in our new space, Te Wāhi Wētā.
The tree wētā we have here usually grow to about 40mm long and weigh between 3-6 grams. They live in holes in the trees and especially love the tiny burrows made by Puriri moths. Males have harems with lots of females, whom they guard ferociously at the tunnel entrance. They leave their home only at night when they search for a nice dinner of bark, leaves, other insects and fruit.
While they look pretty frightening, wētā are closely related to crickets and grasshoppers. That thing that looks like a huge stinger? That is actually an ovipositor, which the female uses to lay its eggs in the soil, while the male has two long sensors called cerci.
Wētā are very important to our ecosystem, and have been described as the “rodents of New Zealand”. This is because they occupy the same niche on the forest floor. For more on the wonderful, wacky world of wētā, have a read of this blog here.
Before you go
Please remember that New Zealand’s insects are special creatures that are important. They are important to our ngā manu as well as our plants and have as much right to be here as anything else. We love our creepy crawlies and we hope you do too!
If you’d like to find out more, join a Behind the Scenes tour (you may get to see where we breed insects for our birds) or enrol your child in our Junior Rangers School Holiday Programme which takes place every school holidays and involves lots of bug hunts. Let us know what your favourite New Zealand insect is by sending us a photo on Facebook or tagging us @pukahanz on Instagram. Together we are all forest guardians!