#SpiderSunday: Jenny By-The-Front-Door

I’ve been trying to keep an eye on the spiders living outside my house as fall transitions steadily into winter. It’s mildly tragic — the thriving summer population of Parasteatoda has been declining, and part of it, I suspect, has been competition and predation, and perhaps a bit of starvation. The mosquitos aren’t quite as thickly swarming as they were in the heat of the summer, and the funnel web spiders, with their grand sheets of webbing, have been edging out the cobweb spiders. The one I called Judy With-The-Big-Leaf who had captured a large, curled, dead leaf and was nesting inside it on the north corner of my house is gone now, and in her place are a couple of funnel webs with their silky tunnels extending in the gap between the siding and the rain gutters. I’ve noticed that Agelenopsis begins with web building down near the ground and expands upwards, so the only Parasteatoda left are in more elevated locations. Poor Judy, she built her nest fairly low to the ground and was overtaken by pushy late-comers.

Jenny By-The-Front-Door, on the other hand, has built a fortress on the wall above the front porch, at about chest height on me, and there don’t seem to be any competitors near by. She’s been building. Wind-blown leaves and seed pods are her construction material, and also some grainy clumps of, I think, insulation that were lying on the ground. She’s actually hoisted them up about a meter and a half to incorporate them, and has been stitching everything together with silk. Here’s her nest as it currently stands.

Can you spot her? I’ll reveal her location below the fold.

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Spider pigmentation is engrossing

I’ve been wrestlin’ spiderlings all day, although they’re getting big enough that they’re showing sexual characteristics, like enlarged palps in the males, so maybe they’re more like spider-teens. They’re about three weeks old — I showed you the newly emerged S. triangulosa a while back. I’m currently raising three species (maybe four) of Theridiidae, P. tepidariorum, S. triangulosa, and S. borealis, and I’m seeing that some of the patterns emerge fairly early and in predictable ways.

This is P. tepidariorum, the most common of these spiders, and the one I’m raising for experimental studies in the lab. Some of its obvious characteristics are the mottled abdomen — although it’s still specifically patterned, as you might see from the clear left/right symmetry — and the dark banding around the limb joints. Less obviously from the photo, one other feature is that they build 3-dimensional webs that take full advantage of the space they’re in. When I open up the container, they’re hanging suspended in the middle of the space.
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Make friends with #spiders today!

Yes! This video speaks the truth!

Today is my free day, and I’m looking forward to just hanging out in the lab with the spiders all day long today. I’ve got some tedium to take care of — bottle-washing — but I also have my S. triangulosa babies to examine for changing pigment patterns, and a lot of P. tepidariorum babies I have to upgrade to new containers, and a lot of egg sacs to harvest, and, sadly, a few adults who have died that I’ll clean out and replace with new stock. A busy day of spidering ahead!

Also, one faculty meeting and probably a few students with questions stopping by, so it’s not all spiders.

Nest-building spiders!

I told you we’re seeing one of the Parasteatoda in the lab is building a fairly dense nest. Today we took a walk around the house and we’re seeing that all the Theridiidae are getting into some intense nest construction. Here’s one example by our front door:

I had gently poked that nest with my finger, and the occupant dropped out of it; you can see her in the photo. I’ll include some closeups below the fold. The nest is a tangle of debris strung together, with at least three egg sacs at the top (at least one had already hatched out).

There was another around the corner, made from a captured leaf.

I’ll be checking on these and any others I find as winter closes in. I’ll be interested to see if they survive the prairie winds, and how they cope with snow and freezing cold. Will a crop of spiderlings emerge in the spring?

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Friday Spider

Oh my. Oh my oh my. While I was out at our climate strike event, I had to, naturally enough, prowl around for spiders, and there she was, hanging out behind the door of the men’s restroom at Green River Park, a stunning beauty, a classic Steatoda borealis, her body all dark and gleaming in confident repose. She’s perfect.

She walks in beauty, like the night
Of cloudless climes and starry skies,
And all that’s best of dark and bright
Meets in her aspect and her eyes;
Thus mellow’d to that tender light
Which Heaven to gaudy day denies.
One shade the more, one ray the less,
Had half impair’d the nameless grace
Which waves in every raven tress
Or softly lightens o’er her face,
Where thoughts serenely sweet express
How pure, how dear their dwelling-place.
And on that cheek and o’er that brow
So soft, so calm, yet eloquent,
The smiles that win, the tints that glow,
But tell of days in goodness spent,—
A mind at peace with all below,
A heart whose love is innocent.

Where’s Brienne?

We go from the sublime to the hideous. When we were doing our routine check for egg sacs the other day, we discovered that Brienne had produced a nice one for us, deep in the elaborate network of webbing she had built in her box. It’s the pale oval on the lower left in this photo.

But…no Brienne. She had disappeared. Look below the egg sac above — there’s a tangled mess below it. I zoomed in on it. It’s an ogre’s nest, apparently.

Ick. Dead flies, bits of dead cricket carapace, all strung together with thick, ropey cables of webbing. Spiders make multiple kinds of web, you know, and these spiders will make cables of web silk that are remarkably tough and hard even for humans to break. I tugged at these with forceps, and nope, they aren’t going anywhere, shy of ripping out the whole structure and possibly injuring its occupant.

Yeah, Brienne is hiding deep inside, the dark shadow near the center of the nest.

These animals always surprise me. They’ve got a complex range of behaviors, and I have no idea what triggered this strange construction. The other spiders in the colony aren’t doing it. I’ve seen a few examples of spiders cobbling together debris into shelters, but it’s not universal, and usually they aren’t this thickly armored and enclosed.

Next they’re going to start assembling tools and weapons, and then you’d better look out.

Now I’m making housecalls

I got a call from campus Medical Services today — they’ve been invaded by spiders lately, and were wondering if they should be concerned. So I scurried over, because I’m wondering what exciting kind of spider they’ve found…although also I predicted exactly what it would be, and I was right.

They had a squashed specimen, and it was Agelenopsis, a grass spider, just like the one captured here in the science building the other day. I told them they were perfectly safe, these aren’t going to bite anyone, and they aren’t at all venomous to humans, but I guess they need to keep on smacking them, since they are a medical clinic and it wouldn’t do to have spiders everywhere. The problem is that this time of year the males are horny, and they’re wandering everywhere looking for mates. Also, they had an exterminator come by yesterday and spray all the vegetation outside, so all the nearby females are probably dead and they’re getting desperate.

I also checked out ceilings and corners, and I’m sorry to say our medical services office is stunningly pristine, with no cobwebs anywhere. Darn.

The grass spiders are invading the science building now

At last, I’m useful! I was called to a colleague’s office because a big ol’ spider was squatting on their papers, staring at them, so I was summoned to capture the beast. I wasn’t too useful, though, since it fled under the desk and we couldn’t find it again. But later a brave student, Sophie, encountered it and scooped it up, and here it is. It’s Agelenopsis, a grass spider, perfectly harmless, but good sized for its species.

I will remind everyone that we’re hiring an ecologist, and one of the bonuses of working here is that I’ll be at your beck and call to handle any office spiders. Or if I fail, we have many bold strong students who are not at all intimidated by monstrous creatures.

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