Insects, arachnids and other life I have seen in caves

My other passion in life is caving. Because I live in a cold place and most of the caves I go in are also pretty cold, I don't see too much life in caves. But because I live in a cold place and caves generally stay the average temperature for the whole year, they are warmer than outside in the winter, so insects and arachnids sometimes over winter in them, especially Harvestmen (daddy long legs or Opiliones), which incidentally are arachnids, but not spiders and do not possess any venom at all. Anyway, here are some of my favorite shots of life I have encountered on caving expeditions.

Cave cricket, Vancouver Island

Fungus growing on pack rat poo

Moth, cave entrance near Canmore, AB

Fungus growing on some old wood

Harvestmen huddling together for warmth, near Canmore, AB

And the occasional human visitor

Escapes do happen - Sparassidae spp.

I have had a few escaped spiders and ant queens now. Mostly they happen when you are transferring a spider from one home to another, you expect this to happen and you can deal with them pretty quickly by having a plastic deli cup close by. Some of my escapes happened not when transferring but when the containers proved not be perfectly suited to the creature, such as my wolf spider (Hogna carolinensis) spider Fred, who pried himself between two layers of plexiglass and made a permanent escape, or my false black widow spider (Steatoda gross), Mavis who disappeared through the gap in the lid of a terrarium never to be seen or heard from again, like socks in a dryer. And there are still a few of Margaret's babies wandering around the house, if you recall one of my previous posts.

My spider room also happens to by my guest room, and more than once I have lied to house guests about having never had any escapees. There is no point in frightening people when all of my spiders are basically harmless anyway, right?  Jenn, I hope you aren't reading this right now, but if you are please forgive me, nothing bad happened, right??

But yesterday's escape of my huntsman spider (Sparassidae spp.), Ginger, was particularly unique, and a little problematic. The top of Ginger's container is attached with Velcro.  Usually the noise of prying off the lid is enough to send her running for cover, but yesterday for some reason, as I was flipping the lid off, she flipped herself over and somehow launched herself at the lid, then ran off of it and down the container, across the desk and up into the bucket that I keep my crickets in before I could blink.  Huntsmen are stupid fast. I guess she really was hungry, because she immediately caught and started consuming a cricket.  Problem was she was now in container with very rounded sides, and every time I tried to corner her with a deli container she simply ran out the gaps on the top of it, and headed for the opening, where (panicking only slightly) I scooted her back down with an energy bill.  It took awhile to catch her, and in the meantime, I estimated she caught about 5 crickets and was slowly digesting them into a gooey disgusting ball.

Not my usual feeding protocol, at least it didn't used to be.

This led me to think about how I have been feeding all of my huntsman spiders, and led to today's experiment with Huntsman #2. I have been giving these guys a cricket a day through the top of the container, and often removing the uneaten cricket the next day from the bottom.  After this incident, today I took the bottom off of the other Huntsman's container, took the moist cotton out that I use as a pseudo substrate, and put about 15 crickets in there instead.  Sure enough, Huntsman #2, "Nicey", descended after a few minutes and started gobbling until she also had massive gob of grossness in her mouth.  I think I have been doing this all wrong, but now I know how these guys need to eat!

My huntsman containers, Costco food containers with the top cut out and plexiglass velcroed on.

A ridiculously easy spider to keep, and a pleasure - Meet Steve

Steve is a European House Spider, Tegenaria gigantean, the kind that people often find in their sinks or bathtubs.  Contrary to the rumors, these spiders do not crawl up the drain, they fall into the sink or tub while looking for water, and they can't climb back out because they can't climb slippery surfaces.  Steve was almost microscopic in size when I received him.  He came in a pill bottle with no substrate and a lot of webbing. I have kept him with no substrate because I have since seen his brethren in their "natural" setting, usually a shed or a garage, where they live well off the ground in a whole lot of webbing. It's my anniversary with Steve, I got him a year ago and in the time I have had him he has molted 8 times, initially molting every 2 weeks, then slowly down to monthly plus, molting for probably the last time in September, at about 9 months of age.

Steve in all his beauty

Personality-wise, Steve is very scared. If I so much as look in his direction he retreats. Unlike my Carolina Wolf Spider, Hogna carolinensis, who would put up with being stroked by a paint brush for awhile before turning to attack it, Steve retreats if I touch him and has never turned to strike.

He builds vast sheet webs with a funnel escape in one corner.  His webbing is incredibly strong, when I open the container it pulls away with an audible rip. Every day or so I spritz a little water onto his web for him to drink.  I have never seen him actually drink it.

A distant cousin of Steve's, in a slightly more natural setting.

He is a ferocious hunter, though not always immediately. It seems to take him awhile to sense that there is prey in the vicinity.

He is also a prolific pooper! I have moved him numerous times to get him away from his masses of faecal material on the floor of his various homes.

Happy Anniversary Steve!

Steve's bare bones home

Time between molting for different arachnids

Almost since I began keeping arachnids I have been keeping a log of feeding, molting and rehousing of all of my arachnids. Mostly because I have the memory of a mouse, and if I don't keep track I will have no idea who is due for what, and they would all probably starve.  I have noticed, not surprisingly, that as animals get older, the time between molts grows longer.  I thought I would look a little more closely at this to see if I could figure out how to predict the next molt for an individual. Well I haven't gotten that far yet, but I did find an interesting pattern.

In the following graph the green lines represent my four Amblypygi (Tailess whip scorpions), the black lines represent three different species of tarantula, and the red line represents a single true spider, my Tegenaria gigantean (giant European house spider).  Please note, the Y-axis is a bit arbitrary.  Day 1 was simply the first day I started the log (and I got the animals at different points in the log), and the first molt wasn't necessarily the first molt ever for the animal, they may have molted before I got them. The best fit for these lines would not be a straight line, obviously, but just for interest sake I treated them as straight lines and calculated the slope.  The Amblypygi have a slope of between 103 and 185, the tarantulas between 40 and 68, and the true spider at 29.  This means that the number of days between molts for the Amblypygi goes up much more steeply as they age then either the tarantulas or the true spider. I was a bit surprised by the difference between the Amblypygi and the tarantulas, because I thought the slope might be related to the longevity of the animal, but Amblypygi and tarantulas are similarly long lived, and and least some species of tarantulas live longer.  However, Amblypygi molt their entire lives, albeit very seldom as adults.

What is the application of this?  Nothing much that I can think of . . . for now. It would be useful to be able to predict when an animal is due to molt. Usually their behavior gives it away, not feeding, hiding, etc. But sometimes we miss these subtle cues, and a cricket loose with a molting animal can be disastrous. Knowing a range of when an animal is likely to molt could make me more careful about feeding.  Also it's just kind of interesting. Another question I would really like to answer is will stress cause them to delay molting?