Unusual "pairing" behavior in Araneus diadematus

Every year around this time, I can always look forward to observing orb weavers. We get Araneus diadematus around our home in large numbers, so I'm quite familiar with the species and its typical behavior, including courtship. However, I noticed something strange 3 days ago in a female's retreat. Her web had been destroyed, so I looked up into the retreat to check on her and saw more than just 8 legs... So I looked closer and noticed a male resting right next to her - so close that they were touching side by side. They have been there ever since and the female has failed to construct a new web.
Any time I saw mating A. diadematus in the past, the two spiders would always be in the web together to mate, the male leaving immediately afterwards. Perhaps they're postponing the mating because the web has been destroyed? Even so, I am very surprised that the female has put up with the male's presence all this time.
Has anyone noticed or heard of anything similar to this before? I am very curious about this and would appreciate any second thoughts.

Contributed by Jackie W. on 24 August, 2011 - 1:21am

I bet the female wasn't mature yet...

Males mature way before the females and will often hang out with immature females, waiting for them to mature. They kind of "stake their claim" on the female. This happens in quite a few different species. Personally, I've only witnessed it first hand in two species: Araneus diadematus and Steatoda grossa... but I've seen images and read papers about many other species that do it.

There are actually about 6 pairs of A. diadematus on the outside of my house as I speak doing this exact same thing. I ran outside after reading this post to snap a shot of one couple to show you, so the photos are literally from about 5 minutes ago. They were high up on the wall of the house, so the pic isn't that great, plus it's dark, so I was using a flashlight... but you can clearly see that the male is mature and the female is not. This particular pair has been sitting together since at least 3pm yesterday, when I first looked at them (it's 2:45am right now). Here's the shots: http://bugguide.net/node/view/570683/bgimage

I've seen plenty of adult males of this species so far this season but not one single adult female yet.

… Mandy Howe, 1 September, 2011 - 4:52am

Very interesting!

That makes a lot of sense. When I first saw the couple, I found it odd that they were together in the first place because the female did not seem to be mature yet. I should have mentioned that earlier.
Very interesting though! I've never witnessed anything like it before.
Thank you for solving this little mystery, it had me very curious! :)

… Jackie W., 2 September, 2011 - 7:09pm

...

Glad we could figure it out! I'm always amazed by spiders... I always learn something new, probably every day, even. I snapped another picture of the same couple tonight... this time they were much closer together, I think touching legs, too! I uploaded it here with the others in frass http://bugguide.net/node/view/571493

And I spoke too soon about not seeing a mature female yet this season... I saw three yesterday! I think they were from the batch that overwintered. I heard that some immature A. diadematus overwinter, while others hatch in the spring. So I think the tiny ones I'm seeing are from the spring hatching and the larger mature females must have overwintered as juveniles.

… Mandy Howe, 3 September, 2011 - 3:12am

We are fairly close in region

but I think your spiders might be more mature than mine. I keep seeing quite young spiders... though I did see one mature male the other day. Also where I used to see numerous webs I am now seeing very few. I think many have succumbed to the black and yellow mud daubers. This is all in my very small back yard... so I guess it is a microhabitat and not very representative of Puyallup in general.

… Lynette Elliott, 9 September, 2011 - 6:21pm

Spiders are infinitely fascin

Spiders are infinitely fascinating for sure. I've admired them since I was little but I was always somewhat hesitant at first because I was brought up by a bunch of arachnophobes! But that uneasiness has been long gone. Are your porch spiders still coupled? The ones I saw were together for a few days. It amazed me that the female didn't chase off the male!
I've seen a lot of A. diadematus overwinter as well, including fat adults that lay their eggs as late as March! We experience some pretty brutal freezes here too sometimes so it always amazes me when I find them still clinging onto life.

… Jackie W., 9 September, 2011 - 6:09pm

Wow

I didn't even know they could lay eggs that late. Impressive.

… Lynette Elliott, 9 September, 2011 - 6:22pm

Happens with Araneus marmoreus as well. Among the subadult females I saw around my place early last month were several with an adult male, sometimes two, lurking in their web.

… John Sloan, 1 September, 2011 - 10:55pm

Two males

Good to know about A. marmoreus! ...and tonight I checked on the same couple in the images I shared and there's now two males! The "new" male is a little more removed from the original pair but he's near enough to likely be touching the webbing, at least. Interesting! First time I've seen two males after one immature female before (though I'm sure it happens a lot).

… Mandy Howe, 3 September, 2011 - 3:05am

That's weird

I have a ton of them and none of them have paired up that I've seen. I'll have to take a closer look.

… Lynette Elliott, 1 September, 2011 - 8:32am

Unusual "pairing" behavior in Araneus diadematus

I wonder if they got stuck during mating. Does that happen?

… Lynette Elliott, 29 August, 2011 - 12:04am

I thought the same thing at first...

I got a good look at them and they weren't in position for mating. They were side by side facing the same direction. I took an even closer look to check for the male's palps, but all was normal.
After posting this topic, I returned the same night to find the male slowly making his way away from the retreat, but the female was no where to be seen. I've checked the area around the spot each night and haven't seen the female anywhere.

… Jackie W., 30 August, 2011 - 11:25pm

Interesting

Perhaps they were just worn out? Maybe the females leaves to find a secluded place for her egg sac.

… Lynette Elliott, 31 August, 2011 - 9:17am

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