Yesterday, as we were traveling, we made a stop at a rest area to look for spiders, as one does. It was a terrible day for spider-kind, with intermittent rain and constant mist and cold, so it was mostly a fruitless search. I did find one sad, bedraggled looking Parasteatoda clinging to the underside of a handrail, with a fat drop of water beading up on her tattered web, and she fled as soon as my camera lens nudged in her direction. Just to make her day even worse, I then scooped up a couple of egg sacs she had in her nest, stealing her babies to bring back to the lab.

This morning as I grabbed the vial of sacs from the Big Spunk rest area to bring in to work, I noticed that they had hatched out! Baby spiderlings everywhere! They were probably triggered by being brought in to a nice warm house.

If someone is passing by Big Spunk today, could you stop in and tell their mama that her babies have found a good home, and we’ll take care of them? Probably more of these will survive here than they would in a drizzly empty wilderness where even the mosquitos weren’t flying.

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.
[Read more…]

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?

[Read more…]

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.

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.

I was at our student summer research presentations. Look at this clever pair, showing off their poster to a milling mob. They did good work.

But now I get to go home and pass out, maybe get some dinner.