How To Identify These Pests And Protect Your Bees
Wasps are a recognisable pest in New Zealand, and one you don’t want hanging around your property. Not only are they a nuisance to humans, but they also pose a significant threat to bees, native insects and even our native birds.
To feed their larvae, wasps need sugar and protein so they spend their days competing with bees for flower nectar and honeydew. They have no boundaries – they’ll attack a hive that’s stored with honey or sugar syrup, eat eggs and larvae and even attack the bees inside.
But there are things you can do to keep that from happening. We’ve outlined everything you need to know about wasps – from wasp ID to keeping them out of your hives.
Wasps vs bees
Though at first glance they may appear similar, bees and wasps are very different creatures. Here’s how you can tell them apart:
- Wasps are thinner and bees are rounder in shape.
- Wasps have a ‘waist’ where their body joins that bees do not have.
- Wasps have longer legs and bodies.
- While they are a similar colour, the yellow stripes on a wasp are much brighter and more obvious than that on a bee, which is more orange-brown.
- Bees are furry, while wasps have a smooth, shiny body.
- Wasps are generally more aggressive than bees and hang around humans, food or rubbish.
Impact of wasps on our environment
No one wants a wasp hanging around their home. A wasp sting is not only painful, it can be dangerous – some people are allergic to the venom transmitted to humans through a sting. But the impact of wasps goes far beyond human annoyance – their growing population is damaging to honey bees, other insects and native birds.
In a hive, wasps can cause havoc. They will steal honey stores, eat eggs and larvae and even attack and kill adult bees. It takes around five honeybees to kill a single wasp, so it can be almost impossible for your bees to fight off a major invasion.
Wasps are also big fans of honeydew – a sugary liquid produced by the bark of the beech tree. Honeydew is an important food for birds in beech forests, so overconsumption by wasps poses a threat to our native birds and the forest ecosystem. There have also been reports of wasps eating native insects and even killing newly hatched birds.
Types of wasp in New Zealand
In New Zealand we have several types of native wasps – these evolved here and don’t pose a huge threat. But since the 1940s, four different wasp species have been accidentally introduced to our ecosystem. These are all now classified as pests: the German wasp, common wasp and two types of paper wasp.
- German wasp (vespula Germanica)
The German wasp arrived in the country accidentally in the 1940s – migrating back with soldiers on a ship at the end of the Second World War. German wasps are slightly larger than honey bees, at around 12-17mm in length. They are bright yellow and black, with a distinctive row of black dots along their backs.
German wasps live in large colonies and their nests are grey. This is the most commonly found wasp pest in New Zealand. Due to our mild winters and abundance of food, New Zealand has some of the highest densities of German wasps in the world.
- Common wasp (vespula vulgaris)
Common wasps are well established in New Zealand – taking over beech forests as the main type of wasp found in these areas. This species is similar and size and colour to the German wasp, but has broader black bands without the pattern of spots along their backs.
Common wasps were first found in New Zealand in the 1920s, but they weren’t classified as a pest until the 1970s. You can identify a common wasp nest by its dull brown colour.
- Paper wasps
Two main paper wasp species have made their way to New Zealand over the years – the Asian paper wasp and the Australian paper wasp. Neither poses as much of a threat as common or German wasps, but it’s still important to be aware of them and know how to tell them apart.
Asian paper wasps vary in size – generally between 13 to 25mm long, whereas Australian paper wasps are smaller, only 10 to 15 mm long. Both species are thinner than their cousins and have long, tan legs, yellow and black bodies, and red-brown wings.
Signs of a wasp infestation
The first sign of a wasp infestation is large groups of wasps around your property, indicating a nest nearby. Wasps tend to build their nests in sheltered spaces: the ground, in sheds, in the wall or roof, in bird boxes or somewhere close to wood.
They make their nests from chewed wood pulp and saliva, giving them a paper-like appearance. Nests vary in size, colour and shape depending on the type of wasp, but they’ll generally increase in size throughout the summer before reaching their peak in autumn.
Prevention and control
There’s no way to eliminate wasps, but there are a few things you can try. Here’s how to manage wasps in your home or hive:
- Prevention is key
The easiest way to avoid wasps is to prevent them in the first place. Maintain a healthy hive, keep an eye out for wasps, and immediately eradicate any nests.
- Make the area unattractive
Try growing plants that have scents that repel wasps, such as mint, eucalyptus, wormwood and citronella, to keep them away from your space.
- Keep tabs on food waste
Wasps are attracted to meat or food scraps. Gather fallen fruit of trees as soon as you can, and ensure lids are tight on your compost and rubbish bins.
- Create a fake nest
Wasps are territorial creatures and are likely to steer clear if they think there are other wasps around. Make one out of a crumpled paper bag and string, or buy one.
- Get a trap
Catching wasps is an effective way to keep their population down and lessen the chance of them building a nest. You can buy a trap, or make your own using a plastic drink bottle, detergent and tape. Make sure to use a savoury, meat-based bait to ensure you trap wasps and not bees.
Here’s how to deal with a nest
- Wear appropriate protective clothing (including a veil and a mask) – removing a nest is risky and you need to protect yourself.
- Deal with the nest at a time when wasps are less active – this should be in the early morning or at dusk.
- Spray the nest with insecticide spray at a safe distance so you don’t get stung or inhale the spray. For a natural alternative, you can use a mix of detergent and water.
- Underground nests can be trickier. If you can see where wasps are entering, pour the spray into the hole and then cover it with stones or soil.
- Don’t stress if you don’t get rid of every single wasp. Removing the majority will still be beneficial to your bees.
Wasp the problem?
Wasps are not only a pain during a summer barbeque with friends, they also cause significant harm to our native wildlife and our bees.
Keeping an eye out for these nasty invaders is the best way to prevent serious damage to your hives – your bees will thank you for it.
Want to learn more about wasps and other pests? Check out our articles here.