You would think that a spider as robust (and venomous) as a huntsman spider (Sparassidae) would be pretty safe from predatory and parasitic insects. But not so. This article is the first in a series on the insects which make a meal of large spiders.
A few years ago I witnessed a titanic struggle taking place on a window at the front of our house. A large spider hunting wasp (or ‘spider wasp’) was pulling a huntsman spider backwards up the window glass.
This spider is a female of the species Cryptocheilus bicolor of the order Pompilidae. These gorgeous black and orange wasps find a large spider and sting it to paralyse it.The female spider wasp doesn’t feed on the spider herself – the spider is food for her offspring.
Earlier that day I had seen our wasp digging a nest hole in the sand bank at the rear of our house. Many species of spider hunting wasps place their prey in a nest in the ground (one spider per cell) and lay a single egg on it. The hatching wasp grub feeds on the live but immobilised spider.
I saw her trying to fly with the spider but she could barely lift it off the ground – her wings were damaged as you can see from the image above. Dragging the spider was her best option and she was attempting a shortcut up over the house rather than going all the way around!
The glass was slippery and the spider was heavy and down down down she would slip – sometimes all the way to the ground. Each time she fell down she started the climb again. I have no idea why she insisted on going up glass rather than up the house bricks where she would have had more grip.
Eventually after about half an hour of this frustrating struggle she gave up and began hauling the spider around the house – a distance of about 50 meters. She accomplished the task of dragging the spider to her nest in just a few minutes. After about an hour she emerged from the nest and flew away. I assume she had laid her egg and had no more interest in the nest.
When spider wasps move around on the ground they move in a jerky ‘stop start’ manner and constantly flick their antennae and wings. The video below shows typical spider wasp behaviour (featuring a different individual to the one described above).
There are about 230 species of spider hunting wasps (Pompilidae) found in Australia. This is only one of the groups of insects which attack spiders – there are many more. The image below shows some insects from one such group. What are they? You’ll have to wait for the next ‘one minute bugs’!