Wasps are one of the major reasons why monarch butterflies are declining in New Zealand.

I feel I need to talk more about these dreadful predators more at my talks which has been one of my focuses. As many people don’t understand why their precious caterpillars go missing.

Paper wasps, are similar to German and Common wasps but are skinnier with longer, dangly legs. See photo below.

While wasps can have their benefits (pollination, pest control, eat dead insects etc) here in NZ they actually have a negative impact on our native bird life and our eco-system as a whole. They outcompete some of our native birds for their food sources and are estimated to heavily damage or destroy 8-9% of honeybee hives.

Wasps are one of the most damaging invertebrate pests in New Zealand. They cause subtle but key changes to the food web of our native ecosystems. Wasps actively hunt for food sources such as moths and caterpillars (live protein).

In New Zealand, the wasps find huge quantities of honeydew in our native forests produced by sap-sucking scale insects. This energy-rich food would normally provide food for native birds, bats, insects and lizards. Wasps out-compete these native creatures for this rich resource putting pressure on the natives to survive. I have seen this first hand and have lengthy talks with a DOC worker, who was passionate about eradicating the wasps when staying in overnight huts in the Lewis pass.

When walking through parts of the forest you can hear the hum of the wasps. No sooner 9 people out of 12 in our group got stung. It was noticeable the lack of bird life within the forest. Wasps also attack beehives and steal their honey costing the industry an millions of dollars.

Paper wasps rely heavily on live prey means they aren’t attracted to the protein-based bait Vespex, which is highly effective on German and common wasps populations.

Wasp traps are given to each school that I teach at thanks to EASYTRAP. These are hung in their playground as there is a major problem down there. As we need to get a handle on the wasps so our caterpillars can thrive into healthy monarch butterflies. Plus this also protects our children at lunchtime when eating their lunch and the wasps arrive due to the smell of food.

How you can help against wasps in your own back yard and protect your caterpillars.

  1. Observe the direction in which the wasps leave your garden, as you maybe able to follow to the nest, as they don’t travel far.
  2. Find out more from Merchento manufacturers and suppliers of Vespex, and how you could use Vespex bait to control the Paper wasps https://www.merchento.com/
  3. If you find the nest place a plastic bag over [the nest], pick it up and put it in the freezer and freeze them.
  4. Place your swan plants around your garden next to shrubs and bushes for protection so your caterpillars are not easily visible and harder for the wasps to find.
  5. Once you see caterpillar eggs on your swan plant/milkweed leaves, cover your plants securely with insect netting or bring the plant inside if they are in pots.
  6. The best way to get rid of the paper wasp nests was to douse them in fly spray in the evening, when the paper wasps are less active and less likely to sting.
  7. You could also purchase a ‘caterpillar castle’ which is like an enclosure that keeps them totally safe. These are avialable on my website – but currently out of stock.

Please be careful disturbing the nests, and they could come at you and maybe get stung.

How to recognise a paper wasp:
– They have a longer more slender body than the German and common wasps
– They are orange and black in colour instead of yellow and black
– They have an obvious waist between the abdomen and wings
– They build small, pear-sized nests using wood fibres
– Nests hang from small shrubs and trees, fences and walls and often under the eaves of houses

You can also purchase wasp traps which are really cheap from your local garden centre or supermarket. The ones in the picture are from EasyTrap & NZ made. German and common wasps are also a huge problem these traps will catch the common ones.

Mixture for the traps – There is also a recipe on the box.

Combine 2 cups of apple cider vinegar, 2 cups of sugar and 1 cup of water in a large bowl. Whisk or stir the mixture until the sugar is dissolved. The sweet combination of sugar and apple cider vinegar attracts wasps. Add some cat meat to the mixture or other meat that you may left over as they are attracted to the protein. The vinegar that is used will stop the bees entering. There are many other mix solutions that you can find online.

In addition to diseases & parasites that kill our caterpillars, unfortunately there are many predators that will kill our monarch caterpillars to survive.

Hedgehogs & wasps eat the chrysalides & as well as when they are in a “J” state which is when at their most vulnerable.

Ants & wasps eat monarch eggs and also carry away the newly hatched caterpillars to feed their young.

Please keep an eye out around your plants to see if you have predators. You can protect them with netting around the swan plants and insect castles. Although this is just part of natures food chain, this is why the clever Monarch butterfly lays over 400 eggs as many do not make it too adulthood.

Top Left Stink Bug | Top Middle Assassin Bug | Top Right Ant | Bottom left Shield Bug

A few of the known predators here in New Zealand

Want to know more about taking care of vital pollinators and would like to purchase my book that has all you need to know about creating a beautiful butterfly garden and raising healthy monarch butterflies. Click below and purchase my excellent colourful A4 resource book.

My excellent A4 book. “An Educational Guide on Monarch Butterflies”

USA residents please purchase via Amazon only $11.58 USD.

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