Ogre-face returns!
If you've been following our website since the early days, this story may be familiar to you. But I think that it is so special that it warrants retelling.
We first discovered the Ogre-faced Netcaster Spider (Deinopis subrufa) in January 2016. A female had taken up residence in the wire-netting guarding our lemon tree from marauding wallabies.
Then just a few days ago, during a late night ramble, we chanced upon another one - this time in a more natural setting on one of our forest trails.
Kerri inadvertently walked through the spider's net and I saw her scrambling up a grass stem to safety (the spider, not Kerri). I took these photos as she gazed at me with her pair of beautiful eyes (ditto). Actually, Netcasters, like most spiders, have 8 eyes, but the middle pair in the back row is greatly enlarged to assist night vision.
So it would seem that this species may be present for much of the year, as we've sighted it in both Summer and late Autumn. But its nocturnal lifestyle means that it is unlikely to be encountered during the day, when it hides motionless in dense shrubbery.
Indeed when I returned to the same place on the trail the next day, there was no sign of her. It was only after darkness descended on the forest that I spotted her - this time in hunting pose, with head down, gazing intently at the ground for any passing prey. She hung suspended from the grass stem on a single thin strand of silk.
She had already made a net and was holding it outstretched in her first two pairs of legs. I went back repeatedly that night and on every occasion she was lying motionless in the same position, waiting for some unwary prey to pass beneath her.
It would have been nice to see her actually put the net into action. But that would require a large slice of luck, I imagine. In any event I was worried about disturbing her with my headlight - and it was a rather cold night!
However I did resolve to catch her in the process of making her net. So last night I headed out to her usual hunting spot on dusk. It was around 5:30pm and just starting to get dark - no sign of Ogre-face.
When I returned at 6:15pm, after dinner, there she was, preparing to catch hers. She was in position to begin net making but hadn't yet started.
Then just 10 minutes later - at 6:26pm - she was underway! She had woven a single horizontal strand of cribellate silk in that time.
I shot a bit of video to show her in the process of making this strand of silk. Note how she repeatedly moves her hind pair of legs up and down. They seem to be linked together by another silken strand.
I returned 20 minutes later, at 6:48pm.
She had made considerable progress in that time, adding several more horizontal rows to the net.
Six minutes later, at 6:54pm, it looked like the net was nearing completion. So the whole process had taken not much more than 35 minutes.
Here are a couple more videos of the net making process (excuse my cough halfway through the first of these!).
There is some complex behaviour going on here - coordinated up and down movements of the hind legs and use of the third pair of legs to pull the net towards her body. At times the mouthparts are used to cut web strands.
By 7:06pm, the Netcaster had finished her net making and had assumed her hunting position - body facing downwards, abdomen suspended by a vertical silk line and net stretched wide apart.
There she will lie throughout the night - or at least until she catches some prey.
This ritual is repeated every night. Not only does the net have to be remade every time, so do the retinas of the giant eyes. The photoreceptors in the retina are destroyed as soon as the flash of daylight strikes them the next morning.
What an industrious creature!
