What's the deal with all the paper wasps – and should we be scared?
Not all wasps are bad. Some are annoying. Others are terrifying. New Zealand has native wasps which have evolved here and dont sting. They contribute to plant pollination along with other insects. Australian paper wasps have been in New Zealand since the 1880s, Asian paper wasps since the 1970s. READ MORE: * 'Game changer' wasp control insects on verge of release * Wasp baiting brings back the sound of birdsong in Nelson Lakes * Wasp Wipeout: Do your bit to help eliminate wasps this summer They are active from early spring to late summer, which is why you might have noticed them hovering about recently, or even seen a nest. Paper wasps don't normally cause problems except for gardeners occasionally getting stung when they get too close to their nest, says Peter Lo, an entomologist at Plant and Food Research. One tip for identifying paper wasps: they hover with their legs hanging down like a drone. Far worse are the two types of Vespula wasp: German and common. Vespula wasps are the ones that bother you when you're having a picnic or sitting on a deck with food they can smell, says Lo. They are the ones that can sting you, and if you stand on their nest, they'll come out and swarm, attacking dogs and people. The Department of Conservation (DOC) names them as one of our most damaging insect pests, causing problems for people and competing with native birds and insects for vital food and resources. They are also a major pest of the beekeeping industry, robbing beehives and killing honey bees. First found near Hamilton in 1945, German wasps became widespread, invading native forests. With no natural wasp predators New Zealand has some of the worlds highest densities of common and German wasps. There is an average of 12 wasp nests per hectare or about 10,000 wasps per hectare in beech forests at the top of the South Island, according to Manaaki Whenua Landcare Research. During summer these forests can have 1 0,000 times as many wasp queens as people in New Zealand. The wasps compete with other wildlife for nectar and pollen, as well as feeding on a lot of insects and vertebrate life, says Lo. Thats insects that other animas like birds would otherwise be feeding on. Wasps have even been seen killing newly hatched birds. Most wasps nest die out over winter, with a queen that survives to make a new nest in spring. But when nests survive for a second season they can become huge washing machine sized, says Lo. Wasp can be bothersome for trampers and hunters. Lo recalls coming across a huge wasp nest high up in a tree, when hiking in Whangarei. The track ran under the nest and some kids in the group were stung as they ran past. Recently a school trip in rural Canterbury turned nasty after several children and adults were repeatedly stung by wasps . The Craigieburn area infestation was tackled by volunteers as part of Wasp Wipeout, a campaign launched in 2016 when Stuff partnered with DOC and conservation groups to slash wasp populations. Nests are typically in rotten wood or in the ground. Lo recalls a giant nest on a colleagues Hawkes Bay lifestyle block that was found to be the size of a Mini under the ground, once it was killed off and later collapsed. Lo and his wife have dealt with a few nests in the past using an insecticide dropped around the nest entrance. Doing so involves expertise and protective gear such as bee suits. You have to get very close to the entrance of the nest, and that is where it can get very tricky, says Lo. When you start doing that, they come and swarm you, and they are spraying the air with venom. It is seriously scary, says Lo, who advises people not to mess with a big nest unless you know what you are doing. Wasp traps use a targeted protein-based bait. Traps for garden and general use can be bought from hardware stores. After a decade of rigorous research, a g ame-changing biocontrol programme involving insects is also on the verge of release. If this programme is successful, it is hoped that the buzz of ransacking wasps in beech forests of the Nelson Lakes might one day be gone for good.