It’s Argiope Day!

Over on the iNaturalist site for Spiders of Minnesota, we’ve been tasked with finding Argiope. I hadn’t seen any in Minnesota before (and I’ve been living here for almost 20 years), but as usual, once you start looking, and once you see a few, suddenly their presence just leaps out at you. We found a bunch of them today!

These are among the biggest spiders in Minnesota, and the first one I found, the pictures weren’t so great. I’m used to itty-bitty little beasties, so I’ve got multiple extension tubes in my camera, and all I got were EXXXTREME closeups. Today I popped out most of those tubes. These guys really are monstrous huge, and vividly colored. Once I tweaked my camera, they were also easy to photograph.

We found them in the unmowed drainage ditches all along the highway through town. Well, honestly, Mary found them — she spotted the first, I moved in with the camera, totally focused on the specimen, and she had to yell at me that I was about to walk into another one. She was keying in on the stabilimenta, the thickened zig-zag bands that form a line in the webs, and once she spotted one, she was seeing them all over the place. It got to the point that she’d say “one here, one here, another one here” and point and I’d just go where she commanded.

I’ve put a little gallery below the fold. Get out into nature and open your eyes!

[Read more…]

Another day in the spider lab

I took care of some tedious maintenance work in the lab today — organizing the vials of spiders (lots of them!), double-checking their classification and sex and relabeling them. I color-coded them by species (white is Parasteatoda, green is Steatoda borealis, yellow is Steatoda triangulosa) and made pink and blue stickers for females and males, which tells you the degree of excitement at the lab bench!

But some fun stuff was going on. Remember Brienne, the hugely swollen female that we were sure was going to make an egg sac any day now, and she didn’t, and she kept getting bigger and bigger? She finally got off the pot and laid a big batch of eggs!

Here’s Brienne before:

Here’s Brienne now:

Finally! She hasn’t moved from that corner of her cage, but it’s got to be a relief to expel that load. The egg sac is bigger than she is!

Also, as I was sorting through the spiders, I saw that another egg sac had popped overnight. Here’s a contented female surrounded by her brood in one of our vials:

She’s a nameless P. tep, which seems callous now — we don’t give them names until we move them into the bigger cages, but they’re still quite capable of pumping out eggs in more cramped quarters. Maybe I’ll have to give her a newer, bigger home…and a name. Got any suggestions?

Today’s spiderwalk: featuring a patch of prairie

Getting away from the decaying, abandoned human homes for a bit, we acted on a tip from a colleague and visited Stahler prairie, a lovely spot of land near the university that was donated to us for research and teaching. I didn’t even know it existed until this morning! Those ecologists…always keeping secrets from us lab geeks. But now we know, and we went strolling through the grasses. That’s Mary, off in the distance.

We were disappointed at first — the place is buzzing with bugs, and we found quite a few large webs, but we didn’t see much of the resident spiders. Big empty webs meant there had to be a webspinner nearby, but these are cunning beasts and very good at hiding. We finally found one big Neoscona cozy deep down in a tube made of a furled leaf.

We’ll be back, Stahler Prairie! We’re figuring you out and we shall tease out your secrets!

Spider hunting in the haunted barn

We went on another field trip today, to barns in Hancock. I had predicted that we’d find many more orbweavers in barns than in garages and sheds, and that’s tentatively true. We first visited a working barn, one with lots of chickens strutting around, and didn’t see a dramatic difference in the spider populations, though — I suspect that chickens are going to eat any large, bold orbweaver that exposes itself. These barns had the densest cobwebs I’ve ever seen, and lots of hidey-holes for our friends the Theridiidae, so we only saw a scattering of S. borealis and P. tepidariorum.

Then we saw the abandoned, crumbling farm down the road. “Hey, let’s go explore that!”

Preston led the way through the weeds and thistles.

This place had definitely seen better days. The ceiling was falling in, the windows and doors were gone, you could just walk in through the gaps in the walls. The floors were littered with old debris from long-gone residents. It was a sad place.

It was clearly an old dairy farm. Maya found the milking room.

Maybe we should have turned back when we found the rotting, decapitated doll. If this were a video game or a horror movie, that would be a sure sign we were on the path to Hell.

But what we found inside were…

[Read more…]

Proud mama

I am just astounded at how many of the local spiders are guarding egg sacs right now. It’s as if they know the typical first frost is at the end of September, and then it won’t thaw until maybe May, so they’d better make babies before the killing freeze descends.

LABORATORY INCIDENT!

One of my students dropped a petri dish full of newly emerged spiderlings at approximately 10:15am on 31 July 2019. Containment was breached. Occupants of the dish saw their opportunity and immediately began ballooning, rappelling down from the desktop, and generally making a concerted escape. The air was full of tiny baby spiders on invisible strands of silk wafting about; the authorities made an effort to retrieve the escapees, which mainly consisted of staring cross-eyed into the air and trying to snare balloon thread with paintbrushes and fingers. Many were recovered, but others remain at large.

After I was done laughing, I faced a dilemma. Do I report this to the biology safety officer? I err on the side of caution, and immediately explain the situation to the official in charge, who happens to be me.

Me: Scores of baby Parasteatoda tepidariorum have launched themselves into the air in a mad bid for freedom!

Safety officer: Are they harmless, cute, and adorable?

Me: Yes, very.

SO: Quick, release a bottle of fruit flies so the little rascals don’t go hungry!

Also, we captured some of the escapees into different petri dishes, which effectively reduces the population density of the newborns. Good way to redistribute the surplus population.

My colleagues are going to be wishing I went back to zebrafish. The occasional flood now looks benign.

The story of Monica

This is Monica.

Monica is Steatoda borealis, and she’s huge. She’s twice the size of our Parasteatoda, and looks simply immense after working with our familiar little guys. She’s big even for S. borealis.

I gave her away to another home earlier this summer. A student was looking for a pet spider, and had a nice terrarium setup, and was going to feed her crickets, so it was safe. She showed up at my door today with Monica, and asked, “Is that an egg sac?”

Sure is. Then she said, “I’m not ready to take care of a family,” a very responsible attitude to have, “would you take her back?” And of course I would. So I brought her back to the lab, and set her up in a nice spacious cage, and fed her lots of flies. I pulled out the egg sac and put it in a Petri dish, and that’s when I notice all the little black dots scurrying around in her old jar. This wasn’t Monica’s first go-round. She’d laid an earlier egg sac, unnoticed, which had hatched out probably last week, and laid a second sac, which we’d finally noticed. Here’s one of the many S. borealis babies.

So now I’ve got hundreds of P. tepidariorum babies, a half dozen S. triangulosa babies, and on top of that I’ve just added what looks like 40 or so S. borealis juveniles, and a clutch of S. borealis eggs to nurse. All of these have appeared at my lab door in the last two weeks. Hey, it’s nice, but did they all have to appear at once?

News from the spider baby factory

In the early morning, we go on long spiderwalks looking for wild spiders. In the late morning I go in the lab to look for new spider egg sacs. In the afternoon I sort and tend to spiders. I’m going to have to think of a good spider-themed activity for my evenings.

Oh, yeah, I read papers about spiders.

Anyway, today I can report that a third egg sac is now leaking baby spiders. They are totally cute.

However, in less happy news, the Ministry of Reproduction finds it necessary to report Brienne for willful slacking of her responsibilities. We have been giving Brienne special privileges — the warmest part of the stack of spider cages, lots of food, and we’ve just been expectantly watching her for the last week. Brienne has gotten huge — just look at that swollen abdomen.

Yet she refuses to produce an egg sac, simply sitting in the same spot all the time, growing larger. Well, the Forced Birth Committee of the Ministry is having none of that. We expect her to do her duty and produce a massive quantity of eggs in short order, or we’ll have to move her into a small vial and give her voluminous cage to a more fertile female.

Or maybe we’ll have to give her a new consort. Is she just holding out for a hunkier male?