If there’s just one thing I miss from my zebrafish days, it’s being surrounded by fish tanks. Lovely burbling fish tanks, filled with little dancing fish, so soothing. So nice. So restful.

Well, they’re gone now, so I wanted something to replace them, so I threw together a couple of terraria with spiders. It was easy. First I thought of repurposing all these fish tanks I’ve got, but they’re too large — my spiders are small, these aren’t tarantulas — and the lids were perforated and wouldn’t be any kind of obstacle. Then I found these acrylic display boxes, which are intended for 1/32 scale model cars, or dolls, or action figures. I can do better than that — spiders! So I made a few.

The one on the left holds a bronze jumping spider and a chunk of stick, while the one on the right is Parasteatoda with a simple frame I slapped together with coffee stirring sticks and hot glue. The jumper has its own charm, but is a little on the small side right now (I’ll fatten him up). The house spider is fascinating and is a real distraction in my office. She immediately started assembling a web on the frame, scurrying about, jumping from stick to stick. I really recommend them for everyone’s office. You should get one or two or four.

I also needed some distraction. Oh no! Another egg sac erupted with babies!

I’m not sure what I’m going to do. My incubators are full to capacity. I might have to try feeding them en masse, until they’re big enough to thrive, and then turn them all loose somewhere. Like my house. Mary won’t mind.

Alternatively, you could all buy some of those acrylic display boxes, stop by the university, and I could stock them up for you. Seriously! They’re fascinating! Like aquarium fish, only dryer!

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In case you have no idea what you’re looking at in that last picture, here’s a key.

Hope that helps!

Today I had to take the car in to get new tires. We’re a rural bit of the country, but that doesn’t mean we’re all green and soil and fresh sprouts — this was a tire store next to the railroad tracks with a line of grain elevators across the street. I wasn’t about to hang around in the waiting room, so I went prowling about the industrial wasteland next door.
What did I find? Cryptic machinery, corrugated sheet metal buildings, and iron rails, of course. With spiders!

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I keep telling everybody — spiders aren’t as scary/dangerous as you think. Now I have a paper that quantifies the risk of deadly spider venom. It’s low.

• The increasing popularity of pet arachnids urges some governments to take protective steps to prevent serious envenomations.

• A literature review was carried out to assess which arachnids can be classified as potentially dangerous.

• About 0.5% of all spider and 23% of all scorpion species were classified as potentially dangerous.

• Even envenomations from the most dangerous arachnids have a low percentage of serious or even fatal consequences.

• We conclude that the public threat from pet arachnid envenomations has been overrated.

Here’s the list of potentially dangerous genera.

Note that the list errs strongly on the side of caution. It lists Eratigena, the hobo spider, but says in the text that “there is not a single verified bite that confirms E.agrestis or other members of this genus as dangerous to humans”. Latrodectus, black widow spiders, do have a real record — 23,000 incidents reported over 8 years — but less than half of those cases involved envenomation, and only about 1% exhibited severe effects, and there were 0 deaths. The Parasteatoda and Steatoda species I work on are only briefly mentioned and dismissed because their effects are much weaker than those of Latrodectus.

I’ve also never encountered any of the spiders they list, and I’ve been looking. I guess if I lived in Malaysia or Brazil I’d experience more of the thrill of danger, but here in Minnesota we’ve got a non-existent concern, and even in those tropical countries it’s a relatively minor worry.

(Of course I learned about this paper from Gwen Pearson. It’ll be useful if anyone at the university expresses concern about the hundreds of spiders currently in my lab.)

I’m in the lab, feeding the babies, when I discover 4 more new egg sacs. That means that in a week and a half I’m going to face another inundation.

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This shy cat-faced spider is roosting in the eves of our house, in an awkward little corner that requires me to climb a ladder and twist and crane my neck to get a good look, and even then it’s tricky to maneuver my camera into a good position. So I had an idea.

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My spider family is going mad, spewing baby spiderlings everywhere. I came into the lab today just to maintain and feed the several hundred hatchlings I’d acquired over the past few days, and what do I find? Another egg sac has opened up, and another hundred or more babies are begging for attention.

Yeah, yeah, I was a responsible parent, and I separated out as many as I could and put them into nice clean vials. I’m reaching capacity, though. This means I have about 300+, maybe as many as 400, itty bitty Parasteatoda offspring in my lab, packed into two incubators. Looking ahead optimistically, I can maybe accommodate 60 adults in the lab, if I pair up males and females. It feels weird to say it, but I’m good if I have 80% mortality in the babes.

I suppose if they thrive I can just turn the majority loose in my basement.

Yesterday, one Parasteatoda egg sac popped and sent out a cloud of baby spiders I was struggling to corral. Today, another hatch!

I’m going to be here in the lab for a while. I have to separate these out into individual vials and feed each of yesterday’s spiders. It’s hard work being the Mother of All Spiders. I hope I’ve got enough flies.

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Sorted, sorta.

I estimate there are about 160 spiders in all those tubes. I couldn’t possibly put single individuals in each, I don’t have enough space — so there are two or three in each, with 8 or so in the larger cube-shaped containers. I found an efficient way to move them. I’d just hold the container with the whole clutch at a slight vertical angle, and the babies would make their way to the edge and leap off, rappelling downwards, and I’d lower them on their threads into a tube and brush the silk against the lip, and then cut them off with a sponge. It worked well enough that I had no accidents that I noticed, which in part accounts for the larger numbers here over the previous day’s catch.

These, by the way, are called the H line because I caught the mother and egg sac at the Horticulture Display Garden. Mom is fine, she’s in one of the containers, too.

Both of these clutches are from wild-caught spiders found outdoors, which troubles me a bit. I’ve definitely got to get at least one batch from indoor spiders — I’ve got some egg sacs like that right now, but I’ve had a very low success rate from their ilk. Maybe country spiders are more fecund than city spiders?

I’ve noticed that there are two kinds of responses people make when they learn I’m studying spiders. 1) They tell me about the terrible spider bites they’ve been getting lately, and 2) they ask if it’s true that people swallow thousands of spiders while sleeping in their lifetime. At least now I can cite this definitive response from Andrea Haberkern in answer to the first. Spiders have no interest in biting anyone!

Bite Post FAQs
1. Can anyone tell me what bit me?
Doctors nor entomologists nor arachnologists can ID bites from a bite alone in the majority of cases. There are likely a handful of exceptions, as in the case of some tick bites that have signs but overall this is not the case. So, if a someone tells you “it’s a spider bite” or “it’s a recluse bite” without seeing the animal itself do the biting, chances are it is something else entirely …but, more on that later…

2. What can we do about this bite?
First and foremost- this is a nature appreciation group, not a medical advice group. Medical advice is not allowed by any members. No members, to my knowledge, are medical doctors. If you or a loved one is suffering negative effects from a bite, please seek medical attention.

3. Do you think a spider bit me?
No. The reason for this is boils down to basic spider biology. I would venture to say that the vast majority of “spider bites” are something else entirely. I think many people believe that spiders go around biting sleeping people, falling from trees just to bite you or are sneaking around looking for their next tasty human to chomp on. I’m assuming the reason this is such a common misconception is likely due to a lack of understanding of what these animals are all about. So… spiders evolved venom to eat insects and other small prey. They use it to immobilize their prey. Just like it takes your body a tremendous amount of energy through food intake to conduct daily activities, it also costs spiders a lot of energy to produce this venom. Why would an animal that needs a substance to eat go around wasting it on mammals when it has nothing to gain for it? It wouldn’t. Now, I’m not saying spiders never bite. Any animal with a mouth can bite. If you grab a spider, I bet it will bite you- just like if you grab a squirrel it will bite you. But I don’t hear anyone saying squirrels are jumping into peoples’ beds while they sleep just to bite them. So why spiders? Spiders will bite in self-defense, but just to add to the unlikelihood of being bit by a spider- most species will do several other defense tactics before resorting to biting. These tactics include: fleeing, playing dead, threat displays, falling to the ground, kicking silk at you and, in some species, throwing poop at you. Biting is an absolute last resort, again because venom is energetically costly and its main purpose is to eat not defense, so you practically have to force a spider to bite you. Just to drive the point home even further- I would place money on the fact that I am likely one of the only people in here who has actually been bitten by a spider. But put that into perspective- I have to manhandle, harass and grab spiders, literally thousands of times, for my work…but even still- I’ve only been bitten a dozen or less times out of thousands of rough handling… I’ve deserved it every time. So, no, I don’t think a spider bit you. Even in cases where a spider was in the general vicinity… false blame is likely to blame.

4. So if a spider didn’t bite me what did?
There are literally hundreds if not thousands of other animals (and plants) that are more likely to have bit you or caused you skin irritations. These include anything that does either directly feed on us or uses bites/irritations as a defense. Examples of organisms that are a way more likely culprit for your skin issues include, but are not limited to: some midges, chiggers, mosquitoes, poison oak/poison ivy, horse flies, sand flies, fleas, stinging nettle, ticks, assassin bug defensive bites, conenose bugs, ant/bee/wasp stings and even some plant/fruit eating bugs that will take the occasional nibble.. etc. etc.

5. But but but I saw 2 puncture holes in my skin, it had to be a spider….
This is a myth. I think it comes from a common misunderstanding of spider mouthparts. Most people assume that all spider chelicerae (fangs) face downward like that of a tarantula and therefore cause 2 bite marks. This is not the case. Only the Mygalomorphs (tarantulas, trapdoor spiders and Aussie funnelwebs) have their mouthparts oriented like this. But seeing that tarantulas and kin are much larger spiders- I think you would physically see if one bit you. So, when someone says “I know this much smaller spider bit me even though I didn’t see the spider because I have 2 bite marks” … there several reasons why this is not the case. First, most spiders’ mouthparts are oriented to meet side to side not parallel facing downward (if the visual is too hard to imagine google image search “Mygalomorph versus Araneomorph mouthparts”) So, if one bit you, a single puncture would be more likely from where the 2 fangs meet. Next, if there were 2 bite marks in the skin caused by a spider- this would have to be a BIG spider for them to even be visible- I highly doubt a spider of that size is capable of sneaking in, biting you without you seeing it, then sneaking away in the night to leave you with only 2 little vampire marks as “proof”. Many many insects will bite multiple times in a localized manner, and considering how much more likely insects are to bite humans than spiders in the first place, that again is more likely your little biting friend.
Spiders rule,
-Andrea

As for the second question…no spider would blithely crawl into a large carnivore’s mouth. Do you also think hippopotamuses lounge about complaining about all the humans who wandered into their gullets while they were sleeping? No. The whole idea is nonsense, and I’d really like to know where that myth started. I’ve been surprised at how many people ask me if it’s true that people swallow 8 (or some other number) spiders a night, when only a moment’s thought would tell you it’s absurd.

P.S. I’ve never been bitten by a spider, but then I only work with little house spiders. They’ve also never leapt into my mouth.