Keeping tarantulas, theraphosids, in terrarium
Introduction
Who haven’t seen a large hairy spider on the movie screen or at a zoo sometime? The reaction has been either repulsion or delight – in my case the latter. Since the mid 1970 tarantulas have been available in pet shops, back then most Brachypelma species. It has happen quite alot since then when it comes to the different species that can get obtained and the general care for the spiders. The access to internet have made it possible to get connection all over the world and also to buy, sell or trade tarantulas. In the 1979-80 a successfull breeding was considered if not impossible atleast very difficult. Today lots of species are being bred, and most of the common species are been bred so spiderlings are often available.
About Theraphosidae
What is a tarantula? Theraphosidae is the scientific name for tarantulas, and they belong to a group of spiders called mygalomorphae. In this group you´ll find for example the trapdoor spiders (Dipluridae), funnel web spiders (Hexathelidae) and purseweb spiders (Atypidae) – Swedens only mygalomorph spider belongs to this group, the purseweb spider Atypis affinis. What separates the mygalomorph from the areanomorph spiders (sometimes refered to as “true spiders”) is among other things how the jaws, chelicera, are located and how they move. On a mygalomorph the chelicera are located parallel to each other and move up and down, in areanomorphs the chelicera are located opposite to each other and move toward each other. There are more differencies but the chelicera are the easiest way to see the difference between the two groups.
The number of species are approximatly 850 and new ones are found and described each year. The size varies alot, from around 2cm to 10cm in bodylength. You can find tarantulas in the wild in the west and southwest of North America, entire Central- and South America. In Europe a few species can be found in Portugal, south of Spain, Italy, Cyprus and Turkey. From there across the arabic peninsular, India, entire south east Asia to Hong Kong, up toward south China, New Guinea and Australia.
To keep tarantulas
A good idea is to start with a somewhat calm species, and not with a fast and aggressive one as the first spider.
Good species to start with:
* Aphonopelma seemanni — “zebra stripe knee” — beautiful, easy to care for, easy to obtain
* Brachypelma smithi — “mexican redleg” — beautiful, easy to care for
* Brachypelma albopilosum — “curly hair” — easy to care for, quite cheap
* Grammostola rosea — “chilean pink” — easy to care for, quite cheap, easy to obtain
Not so good species to start with:
* Haplopelma sp. — species in the asian genus Haplopelma is very fast and aggressive.
* Poecilotheria sp. — same as Haplopelma but these are arboreal and larger. They are supposed to have a stronger venom then most tarantulas.
* Pterinochilus sp. — as for Haplopelma, but these are african.
* Theraphosa sp. — from South America. Big, often aggressive, kicks hair that itch terribly, somewhat sensitive to bad ventilation
In general you can say that species from the old world are less suitable then species from the new world. NOTE: there are exceptions!
The terrarium
The terrarium for mediumsized species (approx 15-18cm legspan) should be 30x30x30cm, for the larger species such as Theraphosa, Lasiodora and Pamphobeteus the cage should be a bit larger – ca 45x45x30cm (L W H)
Make sure the ventilation are good in the terrarium. For the smaller species you can have a top lid, while I prefer sliding glass dorrs for the larger species. For the arboreal living species the hight can be increased even thought its not necessary for the smaller arboreals.
Poecilotheria, Heteroscodra and Stromatopelma sp. should be kept in a somewhat higher cage (30x30x40cm) while smaller arboreals can be kept in a normal sized 30x30x30cm cage.
I use unfertilized peat for all species, and just changes the humidity and moist in the peat. The most terrestrial species likes to burrow so give them a thick layer, atleast 10cm – preferably 15-20cm. Add moist to the peat before you place it in the terrarium. Rub water into it with the hands, its the fastest way. To rainforest living species the moist should be high but not dripping wet. For the more dry living species the peat is slightly moisten.
Spray a few times a week for the rainforest species, less for the more dry living. I usually put a slab of cork bark in the cage for shelter before it burrows. A low plastic bowl is a must, even if the spiders seldom drink from it – the opportunity to drink should be there. Never put a piece of cotton or similar in the water! The spiders can drink straight from the surface of the water, and a piece of cotton gets dirty and full of bacteria. To smallspiderling and juvenils its enough to spray the peat a few times a week. For arborealliving species I put a few pieces of cork bark against the sides and backside for shelter. I also put a few branches for extra climbing and to make the cage look a little more natural. Try not to use rocks in the cage cos the spiders can get damaged if she falls on to it. To have live plants in the cage is a matter of choice, but due to poor light in the cage its hard to keep plants. Some suitable plants are Fittonia and Philodendron scandens.
Heatsources
I have used low watt light bulbs (max 25W) for my spiders and that worked well. The ultimate is to be able to heat up the entire room and place the terrariums higher or lower for more or less heat Most of us dont have a spare room for the spiders so bulbs or heat pads can be used. If you use heat pads for terrestrial spiders – make sure to put it on the sides or backside of the cage. Never under the cage cos if the spiders burrow it can get desicated if it not leaves the burrow. Another solution is to get a cabinet to place your tarantulas inside, then you just heat up the cabinet.
Food
Crickets, cockroaches and grasshoppers works well as food items. Avoid pinkies or atleast not so often. If you dont have crickets in a good size for your smaller spiderlings you can get a larger cricket and kill it. Place it outside the spiders burrow or infront of it and most spiderlings will eat it. For spiderlings small crickets or cockroaches are perfect. Give juveniles food 2-3 times a week, and subadults-adults twice a week.
This is in generally, some species will eat more some less. Theraphosa blondi (regarded as the largest species in the world) eats alot and theres no stop in them while Grammostola rosea eat very little. You get to know your tarantulas habits eventually and get a feeling on how much food they want. If you feed them with crickets – make sure the spider eat them all and dont leave them in the cage. If the spider get into molt and a cricket or crickets are left inside the cage they can start to eat it. Make sure to pick up the small food remains after the food items (looks like a dried up ball) Se till att plocka ut resterna efter syrsorna,
Molting
I remember with horror how my first tarantula, a B. smithi, was laying on its back when I got home from school one day. “Its dying!” was my first thought. Luckily it wasnt the case, it was molting. On species from America the abdomen is a good place to see signs of a upcoming molt, they often kick off hairs from their abdomen and they get a small bald spot there. Before a molt this spot turns black.
Above: Aphonopelma seemanni recently molted
During the molting process the tarantula is very vulnerable and can easily fall prey to predators. Young spiders molt approx once a month (depending on species, food supply and temperature) while adults molt with longer interwalls. When the spider is about to molt it stops feeding, then after around a week they hide inside the burrow and spin lots of webbing at the entrance. Its always good to increase the humidity a little bit. Jus before the acctual molt the tarantul will spin a mat of webbing which she lays on her back and molt.
The molting begins with the carapace breaks up and after that the spider press herself out of the old skin (exuvia) and shows her new fresh shiny skin. After the molt she needs to dry up and the new skin gets hard before shes able to feed again. Small spiderlings dry up fast while a adult Theraphosa blondi starts to feed after two weeks. During the entire molting process its best not to disturb the spider. Its hard work to molt and the spider gets easily stresed during this time. Make sure the tarantula got fresh water after the molt.
Handling or not?
My personal view about freehandling tarantulas is not to do it – or atleast as little as possible. Why you might ask. First and foremost its most safe for the spider to be inside its cage and not run around on the keepers arm or hand. They get easily frightened by sudden moves (air flow etc) and can jump away from your hand and down to the floor. Such a free fall would most likely rupture the tarantulas abdomen and the spider dies. Other reasons why unnecessary handling should be avoided are your own safety. Yes there are no documented case of a human fatality due to a tarantula bite – but you cant be sure how you react to the venom. Then many species from the american continent got urticating hairs located on the abdomen used as a defense against aggressors. They are extremely irritating and all are very unpleasent to get into the nostrils or the eye. it can penetrate the eyes iris and inflammations can rise. Move the spider by make it go into a plastic box and put the lid on.
Mating
The highlight in keeping animals gotta be when you succeed in reproducing them, and the same thing with keeping tarantulas. To mate and get spiderlings demands a bit of planning to have a good result.
Something to keep in mind:
* The female have recently molted
* That she are well fed
* That the male are freshly molted
* That the male have made his spermnet and got his embolus loaded
* That the female have time to get to know the male, e.g. place him close to the females cage
When its time to let the male go into her cage, have a tweezer or similar ready in case she makes a move to kill him. After the male have been introduced to the female make sure he starts to drum with his legs. This is signals to the female that his a male and willing to mate. The female starts to respond to his drumming by tapping her legs if shes receptive. The male will approach her very carefully and slow – to see how shes responding to his signals. If shes receptive she´ll let the male hook up her fangs with the specieal pair of hooks on his 1st pair of legs (not all species got them but they use the legs in the same way) and bends her backwards and try to insert his embolus in her epigastric furrow.
After he released his sperm into her he moves away from her rapidly as soon as he detach himself from her.
Above: Leg and pedipalp with embolus, adult Brachypelma smithi male.
If the mating was successful it takes from 4 weeks to 10 months before she produce an eggsack (time depends on species and time for the mating) that can contain depending on species between 100-3000 eggs. The female fertilize the eggs at the same time as she lays them and the eggs are formed to a large ball.
Some species hold the eggsack between the pedipals and move it around to the desired temperature. Other species such as Pterinochilus spp. attached the eggsack, hammockshaped, inside the burrow. It takes from 4 weeks up to 3 months for the eggs to hatch. After they hatch the spiderlings are all white and still not fully developed. After they molt a few times they look like miniatyre tarantulas.
Notes.
This article have been published in the Swedish Herpetological Society magazine Snoken number 1/2002.
References.
Baxter, N. Ronald — “Keeping and Breeding Tarantulas”
All pictures © Lennart Pettersson
