Wednesday, 6 August 2014

A Grasshopper's demise !

 The Wasp Spider first recorded back in 1922 at Rye, has now colonised many suitable habitats throughout the south of the country, the webs are constructed low down in rough long grasses.
where it preys upon grasshoppers and other insects.

Rainham RSPB is becoming a stronghold of this striking Mediterranean spider, with well over a hundred individual webs found this year so far.

And as we approach August / September , the so called spider season, when the female spiders are at their largest, when the males must try and mate, usually to their peril.

There webs can be identified by the strange 'stabilimentum' built into the web, a strange zig zag strand of sticky silk running vertically down the centre of the web. 

You can just make out the 'stabilimentum in this typical view of a wasp spider's web, interestingly, if you look closely at the top of the Stabilimentum you can also make out the form of the much smaller male spider lurking in the background, I didn't notice that at the time.

No one is really sure what the purpose of this 'stabilimentum is, a few theories have been put forward,
 the stabilimentum is meant to reflect ultraviolet light and so attract prey into the web, another theory is that if danger approaches the web, the spider vibrates the web causing the stabilimentum to shake and thus scare away potential dangers, seems unlikely.

While I was watching this particular spider, I think I must have disturbed a grasshopper which landed directly into the web.

The spider with lightning reflexes, appeared to move in, bite the grasshopper with its deadly venom and then appeared to immobilized the hapless grasshopper with the sticky stabilimentum strand on the web,  this may have been coincidence, but you can see the grasshopper with the sticky strand around it.

The spider had the grasshopper disabled within seconds, it then withdrew, presumably to await the deadly venom with its protein dissolving enzymes to do its work.

It would be interesting to observe this spider with other insect catches, I'm sure that this was just coincidence it seems to obvious to have been overlooked by those that study these creatures in detail.

Interesting to watch though.

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