If you go into the forest at night and shine a torch around the tree trunks, you will see tiny pinpricks of light. It is the reflection of spider eyes.
These spiders are not the ones that live in our houses – they are nearly all newcomers, accidentally introduced from other countries. The spiders in the forest all belong there, some of the 2500 odd species native to New Zealand.
At night, spiders are out hunting. In the trees the orbweb spiders sit in the centre of their symmetrical web. Other spiders build a web like a trampoline. These sheetweb spiders lurk in the foliage, holding a few supporting threads and feeling for the vibrations when an insect blunders into their web. Then they will race along the threads and bite the victim.
One bite will finish off a small insect but larger prey may struggle free so they need to be wrapped up in silk threads until the spider venom does its work. The spider will then suck out the soft insides of its parcelled prey. Spiders cannot chew because they have no teeth.
In crevices on the tree trunks you will see small round holes, edged with spider web. These belong to tunnel web spiders. They hide inside their silk-lined tunnels, waiting to pounce on any insect that scurries nearby.
Amongst the leaves roam jumping spiders. They are hard to spot, patterned and coloured to match the leaves and bark. Jumping spiders don’t build webs. They stalk their prey, leaping long distances and relying on their bungy cord of silk, should they fall. Down amongst the leaf litter roam hunting spiders, which look quite big and fearsome – and they are too – if you are a beetle!
All these spiders, and the ones in your garden or house, kill and eat other insects and invertebrates and maintain the web of living things on which we all depend.
Look at them more closely. Don’t be alarmed. Spiders may look scary – and they do kill flies, moths, mosquitoes and other insects – but they are timid and will only try to bite you if you provoke them. And a spider bite is only a nip, not like the sting of a bee or a wasp. In our country only the venom of the rare katipo is really dangerous and that of the white-tailed spider is painful.
You may spot a jumping spider on the window sill. It will be looking at you with its eight eyes, ready to spring on its eight legs. Don’t kill it. It will roam the kitchen, pouncing on pantry moths and flies, a far better way of pest control than fly spray!