NOTES ON THE COMMUNAL REARING OF POECILOTHERIA PEDERSENI

Please take note that I do not recommend the communal keeping of Poecilotheria sp. (or any other species) of tarantulas, at least not for the moment. Those interested in pursuing this generally unexplored facet of tarantula husbandry should remember that cannibalism within such communal colonies will always be a possibility. This experiment is being conducted in hopes that any information gleaned from it may be of assistance to others looking to keep such spiders communally.

After some years absent from the hobby, I’ve decided to delve into the world of tarantula keeping once more in truly hardcore fashion. Upon moving to Minnesota my collection was only 4 specimens in number - since early December that number has risen from 4 to 21. My most recent purchases were a mix of Poecilotheria sp. spiderlings - 5 Poecilotheria striata and 5 Poecilotheria pederseni. The former are purported to cannibalize and, as such, have been housed seperately.

The five Poecilotheria pederseni, however, have been chosen for a communal experiment.

Several species of the genus Poecilotheria are known to be communal - P. regalis and P. formosa are probably the best known and most oft reported species kept communally by hobbyists at large. P. ornata and P. striata are both known to be cannibalistic and the other species seem to fall in various places up and down the line between. Little to know information on the keeping of Poecilotheria pederseni can be found online. As such, any observations I make will be reported here on a more or less regular basis.

First some general information on the specimens.

My five specimens are all unsexed spiderlings ranging from just under to just over 1 inch in total leg span. All are from the same clutch and the larger specimens seem to be one molt, at most, ahead of the smaller. All were healthy and active upon arrival.

Accommodations were originally to be a tall 16.2 cup food storage container (rough dimensions are 4(w)x4(d)x8(h)) - upon receiving the spiderlings it become quickly obvious that anywhere from 10 to 20 of this size could live happily in the container. To help prevent territoriality among the specimens the accommodations were changed to a much smaller food storage container (a large take-out soup cup from the local Vietnamese restaurant, thoroughly washed) - the larger container will be utilized once the spiders have reached sizes of 2.5 inches or more. Substrate is Eco Earth compressed coconut fiber. Decorations are minimal and consist solely of a piece of bark leaned against one side of the enclosure. Extra enclosures of a variety of sizes were made as well so that, should disaster strike, the specimens could be separated quickly. Observations from others who have kept various Poecilotheria sp. communally with success indicates that limited space to reduce territoriality is a key factor - these observations were followed by myself in setting up the final housing.

All spiders were first checked for their general condition - all were introduced into their enclosure at the same time.

01/29/2008

Initial observations were a bit distressing. The spiderlings, obviously stressed from being shipped from the warm land of Texas to the ninth level of hell (it got much too cold here the day of their delivery), were not immediately inclined towards being friends. No violent behaviour of any kind was noted, though general skittishness was widespread. The spiderlings would occasionally sit next to each other, but the slightest of unexpected movements would send all the specimens scurrying in a variety of directions. This sort of activity continued for one to two hours after introduction into the enclosure.

Later in the evening it was noted that all specimens had found their own respective spots in the tank and seemed more or less at peace with themselves. Earlier skittishness was replaced with the exploratory instinct common to all tarantulas introduced into a new environment. Food was introduced in the form of five early instar lobster roaches - no feeding was observed before I retired.

01/30/2008

The spiderlings were obviously busy exploring throughout the night. Upon waking I found them to all be in relatively close proximity. Three are huddled together in the classic Poecilotheria pose at the inside base of the piece of bark while the other two, while not side by side with the others, are no further than an inch from them and are likewise touching. No violence has been noted and all specimens appear to be quite comfortable with the others of their own species that are present. Only two of the five lobster roaches introduced are visible - no food boluses were observed to otherwise indicate that feeding had taken place.

At present one of the specimens - offended by my intrusion so early in the morning - is wandering about the enclosure. Apparently satisfied with itself, it has presently settled with the other three huddled at the base of the bark. Close attention will be paid to the specimens over the next day or so and any individual not keeping with the group will be removed to help prevent potential cannibalism.

01/31/2008

Exploration of their new environment was on the schedule for the previous evening, it seems. Two of the specimens are still huddled together at the base of the piece of bark - the remaining three are scattered about the container. Interaction between specimens is still highly friendly - they allow one another to walk over each other, sit with legs touching, etc. with no sign of aggression. Two food boluses were noted this morning, indicating that feeding had taken place at some point between this observation and the last - no feeding was observed but the remnants of a small mat of web on the face of the bark further indicates its occurrence. As such, three more feeder roaches were introduced into the setup. No further feeding was noted at the time of my morning observations.

Initial conclusions are that the setup is sufficient, for the time being, to allow for amicable interaction and cohabitation of multiple young specimens of Poecilotheria pederseni. Indications are that this species is inclined towards co-habitation (the huddling of multiple specimens together), at least as spiderlings, much as Poecilotheria regalis and Poecilotheria formosa are. Only future observations will tell whether this conclusion is warranted or not.

02/01/2008

On the previous night feeding was observed for the first time when a specimen captured one of the larger lobster roach nymphs that was running about the container. Further interaction between spiders has been witnessed and signs of aggression between them is entirely absent. Specimens walking over other specimens with no ill effects is common during the evenings, when all go about exploring their enclosure, and it has become the norm for at least a few of the specimens to be huddled together in the morning. There has been some minor webbing, though no tube web construction as yet.

One problem that may cause issues at a later date is the presence of a small patch of mold at the base of the piece of bark. This was allowed by my own stupidity in not providing enough ventilation for the enclosure - a problem since solved. If the added ventilation does not put the mold at bay within the next couple of days then steps will be taken to remove it from the enclosure. My hope is that further action will prove unnecessary, as I wish to disturb the colony as little as possible (particularly during this time of settling).

02/02/2007

A large overnight increase in the amount of mold growing on the piece of bark in the enclosure has forced me to action - over the course of this morning the offending decoration as well as the substrate that was molded was removed and replaced with fresh substrate and a limb with a bit of bark placed vertically against it. All of the specimens were well behaved throughout the ordeal and they proved surprisingly manageable. During the procedure only four of the spiderlings were on the removed piece of bark - this allowed for a bit of a photo op on my part.

Upon being reintroduced, four of the spiderlings quickly huddled together - something I’d never expect to see from most other genus. Only five to ten minutes from their reintroduction, the specimens are already beginning to explore. They will be allowed to do so in peace for the next several days, with the exception of food introduction either tonight or tomorrow.

02/03 - 02/06/2008

Over the weekend the specimens have finally begun to settle into their home in a noticeable fashion (the branch+bark solution proved unsatisfactory and has been replaced with a setup nearly identical to the previous one). Much exploring was observed over the weekend and at least one or two of the specimens always seem visible at night. Food has been made readily available (roaches of appropriate size are offered up five at a time approximately twice a week) and feeding has been witnessed several times, most recently by one of the smaller specimens. No aggressive behavior has been noted as of yet.

Construction of a communal tube web began during this time period as well, and at present all specimens have taken to residing within it.

02/12/2008

All is still well with the spiderlings - I’ve noticed that all of them are noticeably fatter than when introduced (evidence that all have been feeding well enough over the past odd week or so). I’m expecting the first molts to begin within the next couple of weeks. Feeding has continued quid pro quo with a handful of appropriately sized roaches being introduced into the container once every two to three days.

The tube web has grown considerably over the past few days, so much so that it presently occupies roughly half of the underside of the piece of bark. Two entrances/exits have been noted - the most oft used is present at the top of the web (roughly halfway up the bark) while the other, presently lightly webbed over, is present at the base. In true Poecilotheria style, the webbing has been almost entirely obscured by a layer of suspended substrate.

The spiderlings, at least for the time being, seem practically gregarious. As of this observation one large specimen is currently sitting partially inside the top entrance to the web with another directly beside it - another is sitting on the top side of the bark with on of its legs stretched around to the other side and touching those of the specimen at the entrance of the web. Exploration by the spiderlings has grown more infrequent and is steadily being replaced by the nightly sit-and-wait hunting behavior common to almost all species of tarantula.

Observations by other keepers of communal Poecilotheria sp. have indicated that the act of feeding may be a communal event as well, with multiple specimens feeding on the same prey item at the same time. Given how they’ve lived together over the past two weeks, my curiosity in regards to this facet of communal Poecilotheria rearing is peaked. The question is, does this behavior occur in groups of Poecilotheria pederseni as it seemingly does in groups of Poecilotheria formosa? I’ve observed such behavior with communal scorpions before (Centruroides exilicauda - they are the only truly communal scorpions I’ve experience in keeping - were often observed by myself to devour crickets in pairs [or more] like they were little invertebrate hot dogs), so it happening within Poecilotheria sp. is certainly within the realm of possibility.

In keeping large groups of Latrodectus macatans spiderlings together I observed that multiple specimens would feed on the same prey item - in their case a mutilated lobster roach a hundred times or more the size of the spiderlings, individually, but introduced into a container of several hundred. Smaller spiderlings (my girl friend’s recently purchased Aphonopelma bicoloratum spiderling, 1/8?, for instance) can also often be fed small bits of pre-killed food in a similar but less disproportionate manner. My initial thoughts are that a larger pre-killed prey item (a sub-adult roach, for example) introduced into an opportune place in the enclosure at an opportune time may provide the necessary conditions for communal feeding to occur. Whether or not this will work has yet to be seen - given the hunting behavior observed by the specimens I am, at least initially, inclined towards pessimism. Then again, I’ve been feeding three extraordinarily stubborn Haplopelma lividum adults (all wild caught and undoubtedly stressed out by their new found captivity) pre-killed adult roaches with much success over the past few weeks, so the results could surprise me yet.

The plan at present is to introduce a pre-killed (and probably dismembered) adult or sub-adult lobster roach at as close to the specimens’ retreat as possible without outright disturbing them in the process - to maximize the possibility of success I will introduce early in the evening, just before the spiderlings’ natural hunting instincts kick in. My work schedule for the next few days may prevent me from experimenting with the idea for the next few days, but any results (or lack thereof) will be written up here in as much detail as I can muster.

It's been quite some time since I updated these notes - over 2 months now! Work has consistently gotten the better of my free time since I started this project, but all pertinent developments in regards to the communal experiment, to date, will be detailed below.

A week after my last posted updated (roughtly around the end of February) the community suffered its first (and thus far only) fatality. The runt of the group, measuring at roughly .5-.75 inches in total legspan, died of natural causes. My suspicion is that this individual, much smaller than the rest, was trapped within the tube web when the others went into premolt and was simply unable to find the resources necessary for its survival. The body was removed by one of the larger individuals in the night and found by myself early one morning lying at the base of the piece of bark.

The remaining four individuals all succesfully molted into spiderlings of approximately 1.5-1.75 inches in length a short time later. Only one of the molts was removed from the confines of the tube web, the others have, presumably, been plastered about it in the manner typical to Poecilotheria (and other) species.

The communal feeding test proposed earlier was tried, and failed. The large roach went uneaten and had to be removed. No further tests have been conducted, to date.

In early March the specimens opened several routes out of the tube web and began becoming active again. Feeding, stopped during the premolt cycle all together when it became obvious that none of the prey items were being eaten, was commenced once more and the spiderlings took to gorging themselves in short order.

Roughly one month after the last molting cycle concluded (the beginning of April) the spiderlings seem content enough with their statures to go into premolt again. The tube web, now greatly expanded and covering the entirity of the inner side of the bark, has been completely closed off once more.

04/17/2008

A minor catastrophe (the unfortunate breaking of the lid to the container used to house the communal setup) has provided me with an opportunity to move the setup into a larger container. Given the current size of the specimens and how much I expect them to grow by the end of the current molt cycle, this is something I'd hope to get done in the near future anyway.

The small container was placed inside of a large rubbermaid storage unit to help contain any would-be escapees - this should be standard operating procedure for anyone moving tarantulas of any species or size. The piece of bark, tube web and all, was carefully removed from the former home and placed inside of the new habitat - a pretzel stick container purchased from the local target which is roughly 4 inches in diameter and 7 or 8 inches in height. The increased headroom should be satisfactory for the spiderlings up until they reach 3 to 4 inches in length.

This relocation also gave me opportunity to briefly observe the spiderlings and the interior of their tube web home. The thing is of curious construction and seems to be comprised mostly of two parallel chambers (approximately 1 inch around, each) that open into larger "rooms" at the top and base of the web. The spiderlings, in spite of being jostled a bit in the process of being moved, seemed quite content.

All four specimens are of good size and look quite ready to molt again in the near future. Two were huddled together while the others weren't far off. There were no signs of nervousness among them, as has been the case since the early stages of the experiment, and their prior skitishness seems to have all but disappeared. That these sorts of predatory animals can and will live amicably among one another still amazes me.

Another interesting observation is that these specimens seem to be growing faster than the Poecilotheria striata I purchased at the same time. Both species were of the same size and age when purchased and, thus far, the Poecilotheria pederseni have all graduated to sizes of 1.5 inches and above, while only two of the Poecilotheria striata have seen fit to do so. I haven't a clue as to what the cause of this may be or whether or not the observation is of any real muster given the relatively small size of my experimental group.

My conclusions regarding whether or not communal rearing of this species is both possible and practical remain generally the same as when I first began the experiment - there have been no aggressive behaviors observed throughout the course of things and interaction between the members of the group have been consistently friendly in nature. I have heard that this may change as the specimens grow larger - and that relocation may have a detrimental effect on the group. Only time will tell and any future observations will, of course, be noted in this article.

05/11/2008

In the last week of April and within two to three days of one another, all four Poecilotheria pederseni saw fit to molt into specimens ranging from 1.75-2" in length. They remained sealed within their tube web for approximately a week, after which they began to appear about the entrance and bark (no doubt ready to hunt). Their first post-molt feeding involved several small roaches (approximately .75" in length) and, for the first time, a freshly molted adult lobster roach (1.25-1.5" in length).

As has been the norm throughout my keeping of them, the group proved voracious feeders. The inclusion of the adult roach was a lucky decision on my part as it allowed me to observe, for the first time, a sort of communal feeding behavior. I, sadly, did not witness the capture of the roach, itself, only the aftermath. It seems that several of the specimens (at least three and possibly all four) were involved in the process and two were observed to be feeding on large portions of the prey, which had been divided in a mildly disturbing fashion between them.

Feedings have been steady since then and involve my placing four appropriately sized roaches (typically less than an inch in length, though a couple have molted to that size after introduction) into the tank two to three times, weekly. It typically takes a day or so for the specimens to find and capture all of the introduced prey items and the schedule ensures that no great period of time elapses in which no food items are present. Growth of the specimens has been steady since the last molts and I expect them to begin entering premolt again sometime within the next two weeks.

Interestingly enough, the movement of one specimen in the vicinity of another, even when entering the tube web, seems to arouse no suspicion on the part of the other specimens. Prey items tend to illicit an almost immediate response with only flurries of legs visible as the colony members race to the top of the hide to collect their meals. The level of comfort observed between specimens is still awe inspiring to me, even at their relatively small size - that animals largely viewed as unsophisticated and ravenously opportunistic predators (I'm speaking of tarantulas in general here, which have an undeservedly nasty reputation) can cohabitate so peacably with one another is, regardless of how long I spend watching them, truly impressive.

This communal experiment has been going so favorably that I've invested some resources into a secondary communal project within the Poecilotheria genus - come Tuesday I will have 15 fresh young Poecilotheria regalis whom, I hope, will prove to be as amicably inclined as these four Poecilotheria pederseni have been. Another article detailing the progress or lack thereof of that community will be prepared once the project is underway.

06/11/2008

Over the course of the past two weeks the four Poecilotheria pederseni (having been in premolt for some time) began to molt again. Growth seems a bit more erratic this go around, with some of the specimens only reaching a length of 2.25" and others growing to an impressive 3"+. With this latest increase in size has come a rather exciting opportunity - for the first time these specimens are easily sexible via visual ventral examination (as described HERE).

The specimens have proved a bit difficult to keep track of given their increasingly reclusive nature - as their size has increased they have become less and less active outside of their hide - but I have positively confirmed the sex of one of the smaller specimens (roughly 2.25" in length) as male and the largest specimen (3"+) as female. This is exciting news, to be sure, as I definitely plan to attempt breeding with this group.

With the increase in their inclination towards reclusive and appropriately spidery behavior has come a decrease in the voracity of their appetites. I expect the molt frequency, up until now once ever 1 to 1.5 months, to decrease considerably from this point on and I suspect that it is this decrease in speed of growth that has led to the apparent decrease in appetite. Nevertheless, the specimens are still feeding quite well as a whole, though the latest to molt (witnessed doing so on Saturday evening) has yet to feed, not surprisingly.

Inter-specimen behavior has remained consistent throughout, with the specimens proving to be positively amicable. Just prior to my opening the top of the enclosure and spooking two of the specimens before taking the photo that accompanies this update there were three of the four specimens huddled at the very top lip of the bark hide, with two of them being at least partially beneath the newly molted large female. It was she whom I witnessed molting and there were no attempts made by the other specimens in the group to molest her in any way, shape, or form during that process.

In other exciting news, I purchased a ~15 gallon hexagonal fish tank, used, and have it set up already as these specimens' future permanent home. This new setup is an experiment for me, in and of itself, as it is my first ever attempt at a living terrarium. At present it includes a multitude of decorative cork pieces, forming the otherwise drab substrate bottom into a visually appealing landscape, accented with tufts of feather moss. I am considerably lacking in experience with moss and, at present, have the humidity in the enclosure stoked and plenty of natural and artificial light present to help stimulate new growth. We will see how that goes.

Just as this project inspired me to setup a communal group of Poecilotheria regalis, the success of both of them has inspired me further. My next project will involve a group of 10 newly hatched Poecilotheria rufilata, which I intend to keep in the same fashion. Expect notes on that project to begin on Tuesday of next week.

09/16/2008

It is much to my regret that this post marks the conclusion of my communal Poecilotheria pederseni experiment, though the end has come because of my growing (but generally unfounded) concerns about the future health of the group and not because of any grand disaster therein.

With only four specimens present, I have become increasingly worried that this group might grow more aggressive as the experiment wore on - while this has, thankfully, not come to pass, the great disparity in size between the largest (4") and smallest (2.5") members of the group has led me to believe that it might should I choose to not intervene. Given that my ultimate goal is to mate the members of this group (now positively sexed as two pairs of males and females) I have made the executive decision to separate the four into their own individual enclosures.

The females of the group constitute the largest specimens, one at 4" and the other a molt away at 3.5". One of the males is currently at approximately 3.5" as well and, I expect, only one to two molts away from maturing (hopefully my largest female will have a chance to molt once or twice more before he matures). The other male, as has already been mentioned, is only 2.5" in length and is not expected to mature until sometime early next year.

No intraspecific aggression was noted at any point during the eight and a half months that the experiment was underway and, were the group larger in number (between 10 and 15) I would probably not have made the decision to divide it. As late as Saturday of last week (13th) I noted social feeding behavior, with the smallest male and female sharing an adult Turkistan roach. In spite of my worrying about my small group, I'm confident that this species can be kept communally provided they are kept in sufficient number. I will definitely make another attempt should either of my females produce spiderlings in the future.

I do not expect there to be any complications arising from keeping these specimens separately, but should such arise they will be noted here. Keep posted for breeding notes for this species, which should begin appearing within the next two months.

ADDENDUM - MATURITY REACHED FOR 3 SPECIMENS
10/15/2008

The largest of the two (suspected) males molted into maturity this past Saturday (11th of October), increasing in size to roughly ~ 4.50". The smaller female (3.50") has been coaxed over the past several weeks into premolt through increased feeding and lessening of available moisture - I misted her tank thoroughly on Monday (13th) and, as if on cue, she created her mat of webbing and molted in the wee hours between 11pm on the 14th and 1am on the 15th. She appears to be just shy of breedable size (over 4" - acceptable for this, a smaller species of Poecilotheria) and is finally showing definitive sexual dimorphism, with her dark dorsal stripe fading rather noticeably. I'm honestly not sure what I'm seeing here anymore in regards to this specimen, with its overall physical appearance being much more male to my eyes now that I look at it more closely. Contrasting that is the exuvium, which looks more and more female now that I compare it with the exuvium from my recently matured male - I sure wish I had a magnifying glass handy . . . I'm thinking that my original sexing was accurate and that I've just confused the hell out of myself with no real justification for doing so - the next molt should definitely settle things one way or the other.

NOTE:
I now believe that the specimen in question above is, in fact, a female after comparing her exuvium with the rather mangled (but very useful all the same) one left by the male during his molt to maturity. You will note in the image below the appearence of (tiny - this species seems to not be quite so obvious, at least at this size, as many of the others I've sexed via exuviums) spermathecae along the epigastric furrow of the specimen to the right - no comparable feature exists in the specimen to the left. For the moment I believe the mystery to be solved. If a future molt dictates otherwise then I will eat my proverbial hat.

Taking into account the other breedable size female of the group (~ 4.50"), it has taken less than 9 months (January 29th through October 15th) for the majority of this small group to reach maturity - anywhere from 3 to 8 months earlier than has been reported for individually raised specimens. Should my mating attempts in the near future prove fruitful I plan on setting up two distinct groups of spiderlings, one raised communally and the others individually, and, with the aid of strict parameters for feeding, watering, etc., collect more definitive observations on the difference in growth rate, if any, between communally raised and individually raised members of this species.

As previously stated, I highly suspect the smallest (under 3" but heading quickly into premolt) member of the group to be male - judging by his present size I don't expect him to reach maturity for at least another 2 - 4 months. My hope is that he can be coaxed into reaching maturity just as the two females enter their next molt cycles, allowing me to breed them again and test Ryan Nefcy's observations that females bred after the molt following a succesful mating may be less likely to produce spiderlings.

This concludes, definitively, this set of communal notes - no ill effects have been observed from seperation thus far and all specimens have settled very well into their new homes. Further observations on these four will be found via breeding notes, to be begun within the next two weeks' time.