What's this Spider doing?

htcdude · #1 (**permalink**) 27-08-2011, 11:48 AM

Firstly I'm sure this is a Garden Spider.

But what is it doing!?! I'm guessing that's an egg sack on it's back?

And the 2 'coccoon' like packages, what are they? I didn't notice at first but looking at it now, the last photo (which is the same 'package' as the one the spider has clutched in the first 2 photos) might be one of my Orange Swift moths?

Any help much appreciated

Nige

The Woodman · #2 (**permalink**) 27-08-2011, 11:56 AM

Hi Nige

The cocoons are silk wrapped prey, I can't tell what the prey items are but you may be right as you can poke about with them.

After the web trapped prey is subdued with a bite, the spider wraps the prey then takes more time in extracting the body juices - probably assisted with enzyme injection.

You'll hopefully get a better explanation from a spider person that'll come along soon.

Meta menardi · #3 (**permalink**) 27-08-2011, 04:02 PM

I think the spider may be Araneus quadratus, it is full of eggs and I can see nothing on it's back but it's back. The garden spider has a more angular front to the abdomen. Araneus quadratus is quite common at this time of year and when full of eggs is very large. A day later, after she has shed them all, she will be a shadow of what she was. Another candidate could be Araneus marmoreus, this is commonly found as a yellow spider, but a variety less common in this country is that red-ish mottled green pattern that you can just see on the edge of the abdomen. This is the commonly found colour at Strensall and Skipwith common, so if you are near there, that could be your answer.

I see you are in Middlesex, not that close to York.

htcdude · #4 (**permalink**) 27-08-2011, 07:05 PM

Thank you both!

The reason I said Garden Spider was because I'm sure that's what was there the night before, but I may be wrong. Nothing there now and it only appears after dark so will check later.

Thanks for the info on it's behaviour

Nige

htcdude · #5 (**permalink**) 30-08-2011, 09:15 PM

OK the spider is still there. Only comes out at night, no idea where it's hiding in daylight. Sac still full. Another photo here:

Any more help for a definate ID? I can't get a photo from the top I'm afraid.

Nige

maggot at toad hall · #6 (**permalink**) 06-09-2011, 11:30 AM

Keep observing as this spider looks like she might lay the eggs soon. I would love to see a picture of it's back if you could get one.
After the eggs have been laid the body will look shrunken, so getting an image of the back before it lays the eggs would show it at it's best.

sebastianbawn · #7 (**permalink**) 07-09-2011, 01:54 PM

Seems to have very pale markings to the enlarged abdomen, would definately go with Araneus quadratus

Meta menardi · #8 (**permalink**) 07-09-2011, 04:31 PM

Quote:

Originally Posted by sebastianbawn

Seems to have very pale markings to the enlarged abdomen, would definately go with Araneus quadratus

If she lays all her eggs, she will shrink to about one third of her present size, and the colour of the abdomen will probably go to a deep red, if she follows the pattern I have seen other years.

sebastianbawn · #9 (**permalink**) 08-09-2011, 06:44 AM

I have really enjoyed learning from the books and fellow Wabber's such as Venger, all about spiders and am a little gutted as I have never seen an Araneus quadratus!

Meta menardi · #10 (**permalink**) 08-09-2011, 04:01 PM

Quote:

Originally Posted by sebastianbawn

I have really enjoyed learning from the books and fellow Wabber's such as Venger, all about spiders and am a little gutted as I have never seen an Araneus quadratus!

There is no better time of the year to go looking for this spider. When located, they are very often profuse in a large group. Heath, moorland and rough grazing are good places to look. Good luck hunting for one, they are an impressive spider when found.