For the sake of brevity, I'm just going to touch on the highlights.  I sincerely hope that this brief guide/caresheet proves useful to someone.

Arizona Bark scorpions are arboreal (that is, they are climbers), and are one of the few scorpions routinely found on more than merely the first floor, so to speak.   They are also, in the words of Gary Polis (or possibly some other giant in the field) considered 'errant', as unlike the majority of scorpions, who do their utmost to preserve every last bit of energy by sitting still for extended periods of time and letting their food come to them, waiting until it is within easy reach before attempting to nail it, Arizona Barks are given to fits of roaming, and can often even be observed chasing prey, a relatively bizarre behaviour, at least compared to the majority of their relatives.

Another interesting (at least to me) facet of these humble Buthids is their communal behaviour:  they are, for the most part, quite social little creatures, and are often found in the wild piled one on top the other, large numbers of them congregating wherever they find digs they deem suitable. In captivity, they do not deviate from that one bit; barring the occasionally anti-socially violent or pugnacious individual, they are, for the most part, downright gregarious, and I personally have repeatedly witnessed some behaviours which I would never have conceived of being present in the world of invertebrates.

As a quick but necessary aside, I should state now that, while I give some possibly finicky-sounding directives in here, please note this is for what I would consider "optimum". Perhaps the word "paradisial" is more fitting, as this is aimed at replicating conditions which are, in some ways, hopefully richer and more conducive to perfect health than nature is.

In point of fact, I'd be willing to wager that AZ Barks are hardy nearly to the point of indestructibility, and could, given even the tiniest amount of leeway, probably flourish in damned near any conditions.  This easily puts them as a top contender for the Easiest Scorp to Keep [tm], as well.

Temperatures, Heating and Humidity

As for temperatures to keep them at, for the adults/general population, I maintain a thermal gradient of at least ten degrees, as well as having plenty of hiding/climbing areas both at the 'hot' and 'less-hot' ends of the gradient, and plenty in-between, allowing them their choice in thermoregulation. As for base temps, I sometimes (though rarely) let it dip below 76 degrees F at night, and sometimes (more often) let the daytime temps hit over 100 degrees F -- but PLEASE note that those are the extremes, which means even on the 'coldest' night there's at least an ~86 degree temp on the hot end, and an ~89 degree cold end on the hottest day.

On average, though, I keep the temperature gradients between 80 degrees F (cold) and 90 degrees F (hot), and they seem to do just fine in that.   Note that I have, and currently do, keep some colonies at elevated temperatures, keeping them between ~89 to ~100 degrees F, although I also increase their humidity while doing so, as (of course) as the ambient temperature rises, the relative humidity drops, and while they are used to life in unbelievably xeric conditions, I've found that augmenting their humidity greatly decreases molting and birthing fatalities.

As an aside, the best theory I've got at present regarding their unbelievably accelerated growth with the colonies I've kept on the East Coast is that the ambient rH is, relative to Arizona, always elevated.   Everything else being equal (digitally monitored temps and equivalent amounts of food and water intake per colony), I documented over a year ago that they mature and grow at nearly TWICE the speed in this state as opposed to their native one, and when I first observed this, dividing them up into multiple colonies which I kept at different but consistent temperatures over a period of time demonstrated that even a heat-increase didn't accelerate the other factors as well as it had in Arizona.   Go figure.

For heating purposes, I've gone exclusively to using heat-tape and lighting, having discontinued the use of the reptile heat-rocks which one can easily find at any local store.   locating heat tape locally is another story, and for those averse to ordering online, a ghetto-esque substitute which can be made to suffice quite nicely is by hacking a Wal-mart special (~$9.99 USD) heating pad, which is essentially just an insulated nichrome wire with a primative control which plugs into the wall.   Please note that I am NOT recommending the use of this method for everyone, as for those not handy with a soldering iron and the like, I can easily see someone making something fire-unsafe via this method...So, stick to heat-tape and lights.   Those two, coupled with a homemade controller (think hacked-up extension cord and a dimmer switch/rheostat) to control the deep-red/infrared spectrum incandescent heat lamp(s) above the tanks, with the dimmer for precision temp control, and (if you like), coupling that with a timer for one light for day/night cycling), and you're well on your way to making a virtually perfect environment for your scorpions.

For the babies (which I generally keep in a separate tank), I keep it significantly warmer, on average about ~6 degrees warmer or more, but raising/caring for newborns, while certainly not that challenging, is still somewhat outside the scope of this brief write-up, so I'll save that for later.

As for temperature, due to possible variance in monitoring and heating equipment, I recommend that one use the standard procedures for determining a comfortable gradient (id est, once they're situated in their environs, increase the heat slowly and gradually until a migration to the middle or other (colder) side of the enclosure is witnessed; once you know how much heat is "too much", you'll have a better idea of what "enough" is).

Humidity in their environment is, unlike for Pandinus and Hetrometrus spp. of scorpion, really not as much of an issue, although as noted above, augmenting their humidity above the average 10% or so of Tucson, Arizona certainly ensures few (or no) molting difficulties/fatalities.   Essentially, just giving the rH in their enclosure an occasional "boost" by misting it every so often is adequate, though due to the *EXTREMELY* low rH in Arizona, and the difficulty of actually maintaining an elevated rH in any enclosure which is open to the air via a mesh screen, it is hard to give an exact estimate of how often one should mist them (e.g., in Maryland, one doesn't have to do it nearly as much).   Considering that indoors the rH is sometimes as much as twice what it is outdoors (it's currently > 30% rH inside, and 30% rH or so is about average), giving two or three sprays with a hand-sprayer cranks the rH -- at least for a few minutes -- to 60%-80%, is certainly more than adequate to keep molt fatalities at less than 2%, according to my observational records.

Environment and Terraria

As for substrate, Barks do not burrow, and couldn't give a rat's poot what their substrate is; I tend to use mixtures of varying amounts of gravel (the smooth, rounded pebble-like stuff which one can purchase by the bag at pet stores, not the harsh, jagged epoxy-coated stuff one dumps into cheap FW aquariums), small coconut/bark chips, and some bedabeast (shredded coconut husk which retains humidity well, again, only necessary for those in dry climes, and actually not even necessary for the keeping of Bark scorpions). Again, depth is not important, as they are entirely uninterested in burrowing.

Essentially, I just use a substrate or mix of substrates which I can jam the heavier ends of driftwood into (which I always try and position so it is wedged against other things, lest it fall and crush anyone beneath it), so the substrate is really nothing more than a covering for the glass bottom of the aquarium, and serves as a naturalistic appearing floor.

More important by far than the floor, however, are the climbing furnishings. While I am quite certain AZ Barks would be just as pleased scampering about on old, rusted license plates and bits of half-rotten plywood, I am aware there are some who feel these things to be slightly lacking in aesthetic value, so as a viable substitute, would suggest driftwood and cork bark, as both afford ample hiding and climbing spaces, the driftwood being a particular hit, as it has no end to nooks ∓ crannies for the Barks to compactly fold themselves up into in little bundles of hidden scorpion joy. Curls of cork bark are equally good (and much lighter, therefore having less risk of being unstable and falling on anyone), and I have several tanks littered (well, piled, actually...) with large numbers of these. A tank which is nearly uniformly one half to three quarters full of climbable wood is a sure guarantee of Bark Happiness, though careful arrangement is necessary if one wishes to have unimpeded observational view of the colony after the furnishings are placed.

I do not recommend they be kept in the small plastic containers which scorps are often kept in (I've kept, and still do keep, a number of other types of scorps in critter keepers etcetera, including young Parabuthus spp., young Androctonus spp., etc.). I do not recommend them for Bark scorps because, being communal, the larger numbers they are kept in, the less-stressed they seem to be -- PROVIDED enough food/crawlspaces/etc. are present. Think of it in the same terms as having a "target" fish in a tank with skittish fish: the skittish species of fish will generally come out more often, and be less skittish, if they can see other fish out in the open, unmolested; I've repeatedly witnessed that keeping (say) three Barks in a 5 gallon tank means they'll generally stick together, in one place, and do a LOT less moving about, as opposed to having 30 or more, at which point you'll catch the most brazen individuals venturing forth by day to sip up a quick drink of water, or to catch the errant cricket, or whatnot. Overall, they simply seem more "comfortable" (well, as comfortable as arachnids ever *get*, I suppose....) in larger numbers.

The other reason I eschew the polycarbonate plastic enclosures for them is because I don't want to think about what that plastic will do when it hits 90+ degrees. In seriousness, it's difficult enough to keep such high temps in a small glass enclosure without cracking it (I haven't done so yet, amazingly); there's no possible way one could safely do it in a plastic one.

Foodage

As for diet, standard scorp fare serves them just fine: crickets are generally always on the menu, and always taken with great relish, it appears. I am sure that roaches and the like would be taken with just as much delight, but as I've had QUITE ENOUGH of those damned crickets escape in the house, I cannot even fathom keeping/breeding any sort of roach that flourishes well enough in this low rH climate to be worth keeping, as a sole escapee...Well, you get the point.

I've also fed them moths (arboreals are not uncommonly found dining on such things in the wild), though crippling their wings beforehand ensures they won't flap around inside the cage for a day or so, irritating the denizens all the while. Again, if doing this sort of thing, just be as sure as you can the insects you feed your pets are not insecticide-laden when you catch them -- no easy task, of course, and crickets remain the biggest staple.

I have yet to witness a Bark scorpion eat a mealworm, regardless of size. I've actually only seen any scorpion (Hetrometrus spinifer) eat mealworms with any consistency. Most seem rather nonplussed when presented with said worms, so I gave up on that long ago.

CAUTIONS AND CAVEATS

Note that the Arizona Bark scorpion is considered 'Medically Significant', which leaves it as the sole species of scorpion native to the North American continent to hold that dubious honour.

Its venom is primarily neurotoxic, and from my own experiences, the sting reports at the ArachnoBoards forums, as well as most of the more recent medical documentation regarding this species are pretty much correct; serious pain at the site of the sting and/or severe local edema and persistent redness are generally a good (and almost entirely conclusive) sign that one was *not* stung by C. exilicauda. Their stings deliver a neurotoxin, and they don't appear to have as many (or, perhaps, any) of the pain-causing components of the stings of many other species of scorpions. In all honesty, the times I've been stung, I've been lucky to feel a tap at the site of the sting, as they can deliver a sting with the grace of an old nurse giving a shot (sharp needle = no pain). In all honesty, the claws on their feet hurt more if they're clinging to the skin of your forearm, I think, than the immediate touch of their sting. I was once subjected to the delight of one stinging me right before my eyes (though I could have destroyed her and not been stung -- it was a large ∓ feisty female that stung me that time -- my goal was to preserve her, which I managed to do), with such deliberation that I almost didn't believe it -- it didn't actually hurt a bit, even seeing her do it. I was still half-heartedly hoping my eyes were playing tricks on me when I felt that tingling spread rapidly throughout my arm, however...

In any event, I'm just trying to ensure that no one decides to keep Barks without knowing about everything involved. True, they haven't killed anyone in decades (not since the 1960's). True, they probably haven't ever posed a serious threat to anyone over the age of 16 or so (I am not aware of anyone > 60 killed by envenomation, though older people are listed as being at a greater risk than your average 30 year old). However, I'm not about to go on a rant about how their danger might have been, well, slightly exaggerated, perhaps, to drum up funding -- I'm not claiming it was, mind you; I mean, how would *I* know?

In any case, just because *I* haven't had any serious reactions (barring the first time I was stung, and while it was hardly a major medical emergency, the first 12-18 hours were distinctly unpleasant, and even the next day had a reasonably high 'suck' factor), does not mean that YOU will NOT.

• First Caveat:       Bark scorps are EXCEEDINGLY adept at hiding themselves on pieces of wood.
• Second Caveat:   Bark scorps are EXCEEDINGLY adept at escaping their confines (as are all scorpions, really).
• Third Caveat:      Bark scorps are EXCEEDINGLY adept at climbing NEARLY everything except for CLEAN glass and enamel.
• Fourth Caveat:    Bark scorps are very, very, very fast, when they want to be. When they 'want' to be is generally at a time when it will pose the most unpleasant situation possible for you, naturally.
• Fifth Caveat:      While anecdotal, there is reason to believe those kept in captivity can pack more of a punch in their sting than those in the wild, due to increased venom conservation and increased water availability.
• Sixth Caveat:     Scorpions can NOT always be seen by their glow under that nice blacklight you have; not in captivity, at least, as you are more likely, with a burgeoning colony of Barks, to have some newly-molted individuals present in your tank, at any given time. While I've found their glow to be fast on the return, it is not immediate, and at least for the first day or so, they have nearly ZERO visibility at all, under nearly any lighting (see the First Caveat, above).

I am sure there are many more I'm forgetting, but those are enough for a topical coverage.

Always wear gloves when reaching in their tank. Always. Do not think you can just "nip in" and pull out that cricket carcass, or shed skin, or whatever. If you do, you will discover the Secret Location [tm] of one of your pets. It will announce its presence, generally with the business end of its telson. You have been warned.

Of course, better yet, don't reach in their tank. Tongs, tweezers and the like have been around longer than you or I. We have opposable thumbs. Opt for tools whenever possible, instead. Don't let this much evolution go to waste.

Make your enclosures positively ESCAPE PROOF. This cannot be stressed enough. Fine mesh is not just a suggestion when dealing with Barks, as the babies are even more Houdini-esque than their parental units. Do not give them a chance to make a showing of their abilities, and you'll sleep more soundly at night.

DO NOT spray their enclosures with ANYTHING but distilled -- not filtered -- water. Even heavily filtered water has *some* minerals dissolved in it, and over time, mineral deposits will form on the glass sides of the tank...Deposits which -- yes, you guessed it -- provide ample footholds for the smaller denizens, which they can and WILL climb up, at which point in time you will get to see just how escape-proof the top of your enclosure really is, as they will do an audit on it for you, free of charge. Cords leading to heat rocks are also easily traversed by kiddies ∓ adults alike, and if you use heat rocks, expect to find Barks merrily walking upside-down on the underside of the mesh as they combine their search for food with their search for liberation.

That should also impart a certain amount of caution when opening their tanks (I prefer the sliding enclosure tops myself) to put food in, etc. Just looking at the kiddie tank right now, there are two 1" long juveniles cooking around the underside of the mesh on top, without a care in the world. If you must transfer Barks, for whatever reason, always use the container-within-a-container technique. If you do not, you will be given the privilege of witnessing just how fast Barks can be, and their ability to do the 'Full Living Room Dash' in under a quarter-second is one they are constantly interested in showing off to you. Needless to say, if you absolutely *must* handle Barks with your bare hands, just don't. I prefer to not handle them, even with my gloved hands. I could, possibly, be convinced, if it were positively necessary, to handle Bark scorps with *your* hands, provided I was not in physical contact with you, nor within touching distance, but that's really where I'd like to keep the limit of my physical involvement in such matters.

Miscellaneous Bark Errata

Barks seem to enjoy hanging upside down. When moving around, they don't seem to mind which way they are facing, up, down, sideways -- it seems quite irrelevant.

After tagging their prey, they quickly clench their mouthparts on it, then dash up the nearest and tallest climbing spot they can, where they then retire, again, hanging upside-down as is their penchant, to consume their meal (with this behaviour, per the literature, presumably evolved so that they could eat with less chance of becoming preyed upon themselves, although I cannot recall offhand whether that is more conjectural or more generally assumed to be proven.

Barks are sometimes referred to as "skittish" or "irritable"; I do not think either very appropriate descriptions.   They are faster than lightning...When they care to be.   As I write this, I'm watching more scorpions than I can count moving, very slowly and deliberately, around their tanks; everyone is exceedingly well-fed, so they are only half-heartedly prowling for food.   If I were to shine a strong light into one of their tanks, I could possibly rouse them into moving with the ferocity and grace which I've often seen them use.

Barks tend to molt hanging upside-down (or as close to it as possible), generally on the underside of an overhanging item (e.g., think pieces of wood or curls of cork bark),   While some of the dumber individuals tend to park themselves up a little *too* high -- something which results in a nice, intact exoskeleton left clinging to the wood, and a soft-bodied invertebrate damaged or fatally injured by their inevitable if precipitous fall, this is less common than one might think, and is, I suppose, just part of the Process Of Weeding Out.   Kind of a pity we don't have more of that going on for Homo sapiens, I suppose.

Owing to their gravitationally negative penchant, they quite often leave behind very complete and intact skins, which are always no end of fun when one gently collects them, undamaged, and leaves them hidden behind appropriate books in the nearest public library or booksellers.

Any contributions to this caresheet are welcomed (just email centruroides -=at symbol=- exilicauda dot com).  While I'd prefer to retain the copyright to this, I am sure I can easily be persuaded to let it be republished without financial recompense.  In any event, please feel free to link to it, and if you do so, please feel free to point out if you've got a Bark Scorpion-related page (or, for that matter, any sort of serious, in-depth scorpion-related site), as I am a constant and avid devourer of information, and I can put up links to other's sites, as well :)

~ J

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This is another reason to strongly consider using heat tape as opposed to anything you have to place inside the tank, and which might have a power cord which would afford them another possible avenue of egress...

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