Notes and Observations on Tiger Spider Communities, Social Rearing of Poecilotheria.
There are currently 15 recognized species of Poecilotheria. ( World Spider Catalog 2015, Jacobi 2015) As the hobby grows methods of keeping them progress. Keeping Poecilotheria communally is often a subject of controversy on social media sites. The word communal alone can be a tricky word to use when keeping these spiders together. Dictionary.com defines the word communal as “1. used or shared in common by everyone in a group.” Some will argue that the word tolerant is a better word to use for Poecilotheria living together. For the purpose of this article I will use the word communal.
Why Keep Poecilotheria Communally?
As breeding Theraphosid spiders becomes more mainstream as a hobby, more additional ways are developed for keeping them. There seems to be 2 common reasons why breeders are raising more and more species in groups.
The ease of feeding multiple spiders at once. Having hundreds to thousands of spiderlings to feed, I can personally say that the time saved by opening one cage with a group of spiders living in it, and releasing a bag full of crickets into it is a life saver. I spend hours every night of the week opening individual jars and putting in one feeder insect at a time for other solitary species.
It’s visually appealing. What’s better looking than one Poecilotheria regalis? Ten Poecilotheria regalis. Admittedly since it’s not a necessity, the desire to keep a tank full of adult Poecilotheria is something we do for our own self gratification. It “looks cool”.
Methods and experiences
To date I’ve raised 5 species of Poecilotheria communally: P. metallica, P. regalis, P.smithi, P. tigrinawesseli, & P. vittata. Additionally I’ve heard of some success with keeping P. rufilata together (Danniella Sherwood pers. comm.). Reports of P. ornata being quite cannibalistic and the lack of spiderlings have kept me from experimenting with them (Gabriel, R. 2007). My first experiment was with P. regalis. This was before internet information was readily available. I had a tall 20 gallon aquarium in which I placed a bunch of tubes and large pieces of cork bark slants inside for the spiders to hide on. I had some second instars that just molted, so I let 10-15 go free in the tank. It was hard to track them all in that large tank, but within a couple of months it was becoming apparent that the numbers were dwindling. I decided to separate them, and it wouldn’t be until years later that I tried again. A bit more informed in the following years, with reports of some success I started raising Poecilotheria spiderlings in groups. It seemed the basic formula that most people were having luck with were smaller cages with slings from the same sac, never separating them. The theory being they won’t set up and establish their own territory if living in close quarters. Perhaps never losing their sense of touch, of their own siblings crawling over one another, keeps them from getting aggressive toward each other. I usually start with about 15 spiderlings in a container measuring 4” x 4” x 8”. They all share the same piece of cork bark to hide behind. Once they have molted a few times and things start looking crammed, I move them into more permanent housing measuring 8” x 8” x 12”. As the spiders grow space issues are offset by periodically removing individual spiders for sales purposes. There has been some speculation that Poecilotheria will grow more rapidly when kept communally ( Bustard, R. & Deaville, M. 1997 ).This has been hard for me to prove as I tend to feed communals more often than solitary spiders. The ease of feeding a group, and fear of cannibalism has caused me to feed my group cages heavily. I have noticed a great deal of size variation within each communal group, but haven't linked it to either of the sexes growing faster. It seems to be random.
Problems and Cannibalism
Multiple spiders living together in tight cages can present its own set of issues. When spiders are forced to live in small cages with limited hiding spaces, it can be difficult for them to find sufficient space to molt. Siblings won't respect the space of a delicate brother or sister in mid molt. I’ve watched them crawl right over each other during molting and have had my share of spiders missing a leg or two after the molt was completed. These problems are usually minor though and correct themselves with the following molts.
Cage transfers are the most stressful time on a communal for the spiders and keeper alike. Moving a group of fast moving arboreal spiders is not an easy task. Most of the spiders rather flee then stand their ground defensively. I use a long handled paint brush to gently guide them into the new larger cage. Some spiders are more cooperative than others while many will run in all different directions. This can make it difficult when you're half way through the cage transfer with two open tanks that both have 5-10 spiders in them.
I have found the most vulnerable time for cannibalism is when it's time to upgrade to a larger cage. With the 5 species I’ve kept like this, on only 2 separate occasions did I actually witness cannibalism. ( P. metallica & P. tigrinawesseli) Both times it was the same night I transferred the group of spiders into new enclosures. Likely taking them out of a cage that they are comfortable and adjusted in, and then introducing them into a new clean cage is like releasing a group of spiders into unfamiliar territory. This puts the spiders out of sorts and it takes time for them to web up and adjust to their new surroundings. Once they were settled in the new housing, aggression was never seen again, even during feeding time.
The only other time I’ve found a dead spider was in the P. metallica group. There was no damage to the body so I don’t suspect it was attacked. It may have starved to death being it was much smaller than some of the other spiders it was living with. As stated earlier in this article I have noticed extreme growth rate differences within the Poecilotheria communities. So much of a difference that I’ve had one inch spiders that were only second or third instar, while living with siblings that have grown to 4 inches in the same cage. The larger spiders were not aggressive toward the smaller ones, but it can make competition for food troublesome for the slower growers. It becomes a cycle when the larger spiders continue to catch more food and grow , while the smaller ones struggle to catch prey. Eventually the size difference will be enough where the feeders that are offered will have to be in a variety of sizes to accommodate the different sized spiders.
Poecilotheria can be raised in groups with some degree of success. With a little caution and understanding the risks, communals can be a great fast way to raise many spiders at once. I’ve only experimented with captive born spiderlings that I produced myself to minimize the risk of financial loss with expensive spiderlings. Although out of the 5 species I’ve kept like this, I only let one go full term where I had full grown adult females living together. I kept 4 adult female P. tigrinawesseli together for about 2 years. One male matured and lived with them for several weeks before he was eventually eaten by one of the females. ( I didn’t include this in my cannibalism deaths as females can kill and eat mature males under any type of mating settings ) The male showed some signs of mating behavior by tapping and rubbing the females legs, but copulation was never witnessed, and the females seemed less interested in mating. After some time I found the females were getting thin and looking stressed so I decided it was time to separate them. They just didn’t look “happy” anymore being large spiders crammed in a small cage. After separating them they began eating well, gained weight, and continued to live healthy solitary lives. So far even with some success I’ve had raising them together so far, I have found it’s best to seperate the adults in the end. It would be interesting to see if reproduction in a Poecilotheria communal is possible. Would the new batch of spiderlings coexist with the previous full grown adults, or will the original old spiders eat the new slings confusing them with prey ? Who knows what the future holds. Captive breeding has come a long way since the birth of the internet. I’ll never forget the awe and chatter in the conference room the day Andrew Smith displayed some of the first images of P. metallica during his lecture at the 2003 ATS conference. We could only dream of owning such a beautiful species back then, never mind experimenting with keeping them communally. Now in 2015 they are one of the most readily available species of Poecilotheria in the hobby today.
My thanks to Dr. Stuart Longhorn and Michael Jacobi for providing me with literature. A special thanks to Danniella Sherwood for the proofread and suggestions.
Bustard, R. & Deaville, M. 1997. Social behaviour and feeding implications in the south Indian ornamental (Poecilotheria regalis). Journal of the British Tarantula Society, 13 (1): 16–17.
Dictionary.com. Dictionary.com, n.d. Web. June 3 2015. http://dictionary.reference.com/.
Gabriel, R. 2004. Poecilotheria regalis feeding young. Journal of the British Tarantula Society, 19 (3): 70–71
Gabriel, R. 2007. Some observations of social tolerance and feeding patterns in Poecilotheria species. Journal of the British Tarantula Society, 22 (2): 42–46.
Gabriel, R. 2011. Poecilotheria formosa, P. metallica, P. miranda and P. tigrinawesseli; Notes and Observations on Their Captive Breeding, Maturity Rate and Sociability. Journal of the British Tarantula Society, 26 (3): 101–110.
Portman, C. 2005. Communal behavior of Poecilotheria regalis. Journal of the British Tarantula Society, 20 (2): 34.
The Tarantula Bibliography. Michael Jacobi, 29 May 2015. Web. 10 June 2015. http://www.exoticfauna.com/tarantulabibliography
World Spider Catalog (2015). World Spider Catalog. Natural History Museum Bern, online at http://wsc.nmbe.ch, version 16, accessed on 6/3/15
Poecilotheria metallica adult communal
Young Poecilotheria smithi living communally
Adult female Poecilotheria tigrinawesselli resting beside each other
Poecilotheria vitatta communal
Rare case of cannibalisms with Poecilotheria metallica