I first noticed them in kunekune pig manure in 2018. Reportedly first seen on Banks Peninsula in 2004.
Adult bugs are up to 8mm long and emerge to fly to new sites after spending their juvenile phase inside the manure.
Over the past few years we (and others out there) have been experiencing an explosion in the number of green shield / vegetable / stink bugs (Nezara viridula). We try and be accommodating to the various other creatures we share the world with, however these things are especially annoying with the damage they do to summer vegetables and fruit. In particular we find they enjoy tomatoes, beans and corn with lesser damage done to capsicums and fruit.
While there are a number of documented predators of this insect the only ones I have actually seen in action are poultry and spiders.
A year or two back I introduced a juvenile bug to a small jumping spider who quickly pounced and commenced feeding. More recently some visiting students noticed a decent sized wolf spider (Lycosidae) lunching on an adult shield bug.
It's reassuring to witness the local ecosystem operating to maintain balance and equilibrium. As the population or one organism increases so does the opportunities for their predators. Knowing this it is essential that our gardens provide adequate and appropriate habitats for these various helpers. And while our tendency for binary, black and white thinking makes us quick to label species as friends or foe we should take a moment to contemplate that, just like humans, other organisms have multiple roles to play, giving and taking as they participate in the dance of life.
So far this summer, which has been punctuated by many brief cool and rainy periods, we have seen very few of the green stink bug. Plenty of other flying insects around, including as small wasp I noticed exploring calendula seed clusters, a popular location for freshly hatched shield bugs.
Here a preying mantis devours a fly on a pear tree.
The good news is... while verroa mites have been found on bumblebees they are not able to reproduce on them however this does make the bumblebee a vector for spreading the mites.
This approach of trying to passively replace grass using seed dispersing annual flowers did not work. Poppies returned for a few seasons before vanishing.
There is a contented buzzing humming emanating from the wall and every now and then individuals can be seen bumbling in and out.
Selected species include:
- Silk tree
- Tree Lucerne
- Winter Sweet
- European hazelnut
- South African tree heath (pictured)
- Shining gum
- Flowering ash
- Hybrid witch hazel
- Green flowered hellebore
- Golden rain tree
- Amur maakia
- Kobus magnolia
- Fraqgrant epaulette tree
- Japanese fodder willow
- Chinese sweet box
- Chinese wisteria
- Black Locust