Large prey for a Redback spider - an unfortunate Grass skink

Such a sad sight, an adult Penny lizard, Lampropholis delicata fallen victim to a Redback spider Latrodectus hasselti.  
Photo Copyright © Gavin Ayre 2014.  

My reaction to walking through a spider's web is automatic; I stand still and wait for a few seconds to see if I can feel something crawling.  Normally there is nothing, but very occasionally I have to brush a very scared Garden orb weaver off my body.  Not an enjoyable situation, but really it's nothing to get overly excited about.  The spider is far more scared than you are, and is unlikely to bite unless it is accidentally restrained or hurt.  Typically it will try to fall off you or crawl to safety.  

When I'm in shorts & bare feet and feel my legs break through a Redback spider's web in the dark, I can't help but cringe.  And that's exactly what happened to me tonight.  I know that more than likely there is a Redback poised in that web just waiting for a small animal to blunder into it's trap.

Redback spiders are something of an occupational hazard here in Australia.  They are found pretty much everywhere in Australia from the heart of our capital cities to our smallest, blink-and-you'll-miss-it country villages.

Their bite is very painful and considered to be a serious threat to young kids and the elderly.  Fortunately there has been an effective anti-venom for over fifty years now.  While I'm neither very young or elderly, I would absolutely prefer to avoid being bitten by a Redback thanks.

Aussie folklore romanticises about Redbacks sitting on toilet seats waiting for the unwary, but that's not at all likely in people's houses.  I have seen Redbacks happily living in "pit toilets" in our local National Parks, but even there Redbacks are pretty easy to see and avoid.  About the only place they are not common in Australia is untouched bushland.  This is not to say they are absent in the bush.  They typically are associated with rubbish or disturbed areas when I've encountered them in the bush.

So how did I instantly know that I'd walked into a Redback's web in complete darkness tonight? Their webs are very strong and have a distinct tangled construction.  There are numerous strands of super-strong silk that stretch down to the ground, and they seem to be under tension.  They have sticky droplets on the end of each strand but are fastened to the ground with relatively weak bonds.  When an unfortunate animal blunders into the web it will adhere to the end of a strand of silk and start to struggle.  Chances are it will hit several other strands.  The weak anchor points break, and the unfortunate animal is hoisted into the web.  It's struggles will ensure two things; it will get entangled with more strands of super-strong silk and it will attract the attention of the spider.

One thing you do NOT want to do is attract the attention of an adult Redback spider, especially an adult female Redback spider.  In this species, the female really is more deadly than the male.  She is about 4 or 5 times larger than the male and her fangs are large & strong enough to readily penetrate human skin.

The thing that made me cringe when I walked into that Redback web tonight was you never know how keen the female is to bite.  I don't know if it's an individual temperament thing, or if it is associated with hunger.  Most of the time a Redback would run away if a large animal entered it's web.  But not always.

I'll never forget watching a very large female Redback rush out into the middle of it's web in broad daylight last summer - trying to find the animal in its web to no avail.  The "animal" was my lawn mower.  It was throwing enough dirt & vegetation particles into this spider's web that the it rushed into the web to catch the "prey" in strong sunlight in the middle of the day last summer.  The noise & vibrations of the mower seemed to stimulate rather than frighten the animal.  You've got to be tough to live in Lake Macquarie !

After my encounter tonight with the Redback's web, I waited for a few moments with baited breath, and then walked to the wall and flicked on the lights.  Nothing.  I started to breathe again.  I returned to the web and tracked down the spider.  I was very sad to see the Penny lizard, Lampropholis delicata bound in silk in the Redback's retreat.  I have had a thing for Penny lizards and Grass skinks all of my life.  They are beautiful little animals and incredibly active and alert.  Spend some time sitting quietly in your backyard and you will be almost sure to see one or two of the four common species going about their business.  They will delight you with their antics.  I don't feel much when I see an insect in a spider's web - unless it's struggling for its life.  But to see such an endearing creature  wrapped up in silk in a Redback's web . . . to me that's a sad end . . . Well, I guess I'm not such an objective biologist afterall.

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It can be surprising just how big a prey item a Redback can handle.  I have found Penny lizards and Grass skinks in Redback spider webs on numerous occasions.  I have found huge Funnelweb spiders and trapdoor spiders in Redback webs.  I have seen images of Redbacks that have even managed to catch and kill small snakes.

In fact, when I lived in the wilds of the Northern Territory, I'll never forget the story of a woman who was envenomated by a deadly Western brown snake in the store-room of her shop in Alice Springs. The hatchling Western brown snake was tangled in the web of a Redback spider, and understandably very, very angry.  It bit her numerous times on the foot.  The lady was hospitalised and required antivenom.  Fortunately she made a full recovery, though neither the snake nor the Redback were so lucky - the shop keeper killed both of them . . .